With the development of society and the improvement of people’s living conditions, air conditioning has become a necessity in people’s lives. But you know what? The placement of air conditioners is also said to be feng shui. The improper placement of air conditioners will actually block the wealth of the family. So how to place the air conditioner? What are the precautions for air conditioning placement? Let’s take a look.On the other hand, commercial ac unit It also brings tangible benefits to everyone and feels useful. It is a model of the industry. https://puremind.com/product-category/puremind-air-conditioner/commercial-air-conditioner/

　　Air conditioning is a typical product of modern houses, and there is no introduction about air conditioning in any ancient geomantic books. However, air conditioning has obvious influence on the geomantic omen of Yangzhai because of its function of air supply and temperature regulation. So, are there some feng shui precautions for air conditioning, a household appliance that only appeared in modern houses? Let’s sum up some questions about air conditioning feng shui.

　　1. The air outlet of the air conditioner should not face the door.

　　It has been mentioned many times that “storing wind and gathering gas” is the basic principle of Feng Shui. One of the major characteristics of air conditioners is that they can spray air to adjust the indoor temperature. These spouted air currents themselves cause direct disturbance to the gas field of the house. The gas field is too strong, and the air flow and the air flow entering the gate will have an impact, which will directly destroy the stability of the gas field of the house. Not to mention gathering wealth, the popularity will be washed away by the gas field of the house.

　　2. Don’t hang the air conditioner on the sofa or bedside.

　　The wall-mounted air conditioner itself is particularly similar to the beam in shape. As we all know, there can’t be a cross beam above the sofa or bedside, otherwise there will be a problem of the cross beam topping. In fact, air conditioners should also avoid the situation of topping. Moreover, the air conditioner itself has cold air injection, which goes straight to the head or body, and the impact is more direct. Therefore, remind everyone that when choosing the hanging position of air conditioner, try to avoid pressing against people’s body parts.

　　Don’t blow the air conditioner directly on people.

　　In the first article, we emphasize that air conditioning can’t blow on people’s heads, which is mainly from the perspective of air conditioning topping. In fact, even other parts of the body, try not to be blown directly by the air conditioner. Although the air conditioner is cool, it is very easy to catch a cold, stroke or backache, which directly affects people’s health. You can manually change the air outlet direction of the air conditioner to avoid being directly blown.

　　4. Air conditioner should not blow the dining table directly.

　　Experienced friends know that long-term use of air conditioners will absorb a lot of dust and germs. Therefore, for air conditioners that are often used, if the filter screen cannot be cleaned on time, it will also cause the accumulation of foul air in the house. If the air conditioner blows air directly on the dining table, these foul gases and germs can easily be directly adsorbed on our food, which will have an unnecessary impact on our health.

　　5. Don’t blow the air conditioner directly.

　　Some friends will install air conditioning in the kitchen because of the large space in the kitchen. But when installing air conditioning in the kitchen, don’t put the air conditioner directly on the stove mouth, especially on the flame. The reason is very simple. This kind of direct gas field disturbance will not only make the flame unstable and cause safety hazards, but also symbolize the hostess in the image. The direct air conditioning will also have unnecessary effects on the hostess’s own body. So remind everyone, if you have to install air conditioning in the kitchen, don’t let the air conditioning mouth directly face the stove mouth.

　　Location of air conditioner

　　Fans must not be placed in the financial position.

　　If the air conditioner happens to be in the financial position, it will blow away your fortune. The financial position pays attention to hiding the wind and gathering gas, and should be quiet and not moving. They are also fast-running appliances, so they will transfer the airflow from the outside to the home, and plants, fish and the like should be used to stimulate the financial position. Fans can only blow away wealth, which is very unfavorable to home wealth and will soon appear. Therefore, we must pay attention to the fact that the fan must not be placed in the financial position.

　　The fan must not be placed in a fierce position.

　　But the fan is a dynamic substance, which is basically a product of making brake gas. Especially when it is placed in a fierce position, it will provoke fierceness, which is really bad.

　　The cold air that doesn’t start is not enough for feng shui effect.

　　Air-conditioning emits cold and frozen gas, so it belongs to gold in the five elements, which is the same as refrigerator. If the summer is long and the opening time is more than half a year or more, air conditioning will have a great influence on home feng shui, but it should be noted that the air conditioning that is not started is basically not enough to achieve feng shui effect.

　　They belong to gold, and the way to find out where to put them is very simple. Whoever wants gold from a family member, putting air conditioning in the position where the member belongs is the most favorable feng shui decoration. If the father wants gold, put it in the northwest, if the mother wants gold, put it in the southwest. The wind released by the air conditioner will create a geomantic magnetic field. Adjusting the tuyere to the upper side is more beneficial to home feng shui, because in the wind direction, it represents the airflow swirling down from the ceiling and the airflow blowing, which is the best form.

　　Its decoration should be based on the needs of the five elements of family members, and can also be used in conjunction with the lucky time of the year. Find out the bad side and the financial side. If the air conditioner is located in the bad side, the air conditioner on this side should be turned on as little as possible, and feng shui objects should be placed to release two black and five yellow.

　　kitchen

　　The kitchen stove is where the whole family can fill their stomachs. If the air conditioner is directly on the stove fire, it will make the stove fire weak, which will damage the energy of the food in cooking, thus affecting the health of the housing people. In addition, the stove fire is also representative, so it has a great impact on the life of couples.

　　Correction method

　　Don’t install air conditioner if you can, but if you must, blow the wind towards the ceiling or sideways as much as possible.

　　dining room

　　When air conditioners are used for a period of time, dust will inevitably accumulate. Therefore, if the air conditioners in the dining room blow directly on the dining table, it is very likely that the dust will fall into the hot food with the wind, and of course, it is easier to cool the delicious meals on the table. Therefore, it is best not to place the air conditioners in the dining room above or near the dining table.

　　bedroom

　　When people sleep, the sweat pores are wide open and the respiratory system is relatively unguarded. Therefore, if the air conditioner blows directly, it will not only make people feel unwell and catch a cold, but also attract evil spirits more easily.

　　Correction method

　　Raise the air outlet upward, or slightly open the window in the room to evenly blow the cold air.

　　study

　　Air conditioning makes people cool, so it has the function of condensing thinking and improving reading concentration. If we can move the air conditioner in the study to the north and use the energy of air conditioning operation, it will drive Wenchang to good luck, which will certainly benefit candidates or people who study knowledge. Of course, remember not to blow the air outlet toward your face or head, lest your head be unbearable before you finish reading the book.

　　sitting room

　　Air-conditioning is a fast-running electrical appliance, so it will turn the outside air flow into the home, and the southwest of the Year of the Monkey will treat diseases. Therefore, if the air-conditioning at home is placed in this position, it will definitely make the family suffer from illness and illness this year.

　　Correction method

　　Use a small fan to change the wind direction opposite the air conditioner. In addition, in the Year of the Dog, peach blossoms dominate the northeast, Wenchang dominates the west, and the northwest dominates the financial position. If you want to strengthen the above fortune, you can also move the air conditioner to this position, which has a strong effect on luck and transshipment.

　　Popularization of feng shui knowledge of air conditioning

　　Nowadays, people’s living conditions are improving day by day, and the popularization of air conditioning has extended to every household. Air conditioning is warm in winter and cool in summer, which not only improves people’s quality of life, but also brings more warmth and comfort to people. Then, from the perspective of geomantic omen, how to make the layout of air conditioners more in line with the principles of geomantic omen, so as to prosper in people’s career, wealth, marriage and health, and improve people’s quality of life?

　　First, the current three types of home air conditioning

　　At present, home air conditioners can be generally divided into wall-mounted air conditioners, cabinet air conditioners and central air conditioners. According to the principles of geomantic omen that “there is evil spirit when visible” and “there is an image that should respond”, it is considered that there are obvious differences between the “existing form” and “supply cooling and heating mode” of these three types of air conditioners in home, so their functions and functions in home geomantic omen will be different. That is to say, different types of home air conditioning layout in the same location may have different feng shui consequences.

　　Second, the interpretation of three key locations of home air conditioning layout

　　1. Is air conditioning suitable for financial position?

　　It is believed that, first of all, cabinet air conditioners are not suitable for financial position. As we know, financial position is the place where the breath in the home gathers, and cabinet air conditioners will occupy the financial position because of its tall body, and then “squeeze” the wealth; Secondly, central air-conditioning is not suitable for the financial position. Generally speaking, the wind of central air-conditioning blows vertically downward, while the financial position in geomantic omen is generally quiet and motionless. If central air-conditioning is installed above the financial position, its airflow will blow straight down, and the financial position will be exhausted, which is actually an image of money not gathering; Finally, it is considered that the wall-mounted air conditioner is very suitable for the financial position, because it just overcomes the shortcomings of the cabinet air conditioner, which is too large and the air flow in the central space is straight down. Moreover, the wall-mounted air conditioner also has the advantages of high and basic lateral air exhaust. Although it is in the financial position, its air flow is discharged straight ahead, so that while strengthening the air flow in the house, it also maintains the relatively stable and gentle replacement of the air in the financial position, and then uses the air in the financial position to keep fresh.

　　2. Is the air conditioner suitable for Wenchang?

　　It is believed that, generally speaking, all three types of home air conditioners are suitable for layout in Wenchang. Because Wenchang represents school, career, official transport, fame, reputation and influence in geomantic numerology, the layout of home air conditioners in Wenchang will definitely enhance the corresponding energy, and then play the role of prosperity. Then, why can the layout of home air conditioning improve the corresponding energy in Wenchang? Because Wenchang’s general five elements attribute is fire, which is often said to be the main fire. The bright wood fire is the most prosperous image in geomantic numerology, while the five elements of air conditioning discharged from air conditioning are aquatic wood, and the five elements of heating discharged are wood fire, while heating is generally used in winter, and water is also used in winter. Therefore, this forms the image of aquatic wood and wood fire, and its breath gathers in fire, which means Wen and Wenchang; Even more, because of the existence of water, the situation of fire flourishing and wood burning will never be formed, which is also the principle of the five elements of “one (water) four (wood) and the palace master Wang Wen” in Xuankong Feng Shui.

　　3. Is the air conditioner suitable for layout at Taiji point?

　　Taiji point is the center of gravity and center point in the home. It is considered that among the three types of home air conditioners, the central air conditioner is the most suitable layout in Taiji. The central air conditioning is arranged at Taiji point. In the cold winter, warm air comes from the sky, which makes the whole home full of warmth. In the hot summer, the cold wind falls from the “sky”, making the whole home full of sweetness and coolness. As we know, geomantic omen pays attention to the word “image”, and this image is the image of enjoying the grace of heaven and meeting your career. However, wall-mounted air conditioners and cabinet air conditioners are difficult to “hide” and are limited by installation conditions, drainage conditions and other factors, so it is really difficult to achieve the feng shui effect of central air conditioners.

　　Third, the basic feng shui knowledge of home air conditioning layout

　　Warm reminder

　　In the layout of home air-conditioning, the direction of its air outlet is particularly important. Generally speaking, the air outlet of home air-conditioning should not face the places where people are active frequently, mainly the “three places” such as seats, beds and stoves. This is the problem of different effects produced by “actively receiving feng shui energy” and “passively receiving feng shui energy” in the geomantic omen of the Ark. That is to say, when the air outlet of the air conditioner is facing the “three places”, people can only passively receive the feng shui energy, and when the feng shui energy exceeds a “degree” that people can bear, it will naturally do harm to people; However, when the air-conditioning geomantic omen is not directly opposite to the “three positions”, people can fully play their active role by actively receiving the geomantic omen energy, and generally there will be no harm caused by receiving the geomantic omen energy too much.

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According to a report by the Wall Street Journal on July 15, people familiar with the matter revealed that business tycoon Elon Musk said he plans to donate about $45 million a month to a new super political action committee that supports former President Trump.

Reported that other supporters of the newly established U.S. Political Action Committee include Palantil technology co-founder Joe Lonsdale, the Winkleworth brothers, former U.S. ambassador to Canada Kelly Craft and her husband Joe Craft.

According to a person familiar with the matter, the political action committee, established in June, is mainly responsible for registering voters, persuading voters to vote as soon as possible, and requiring ballots to be mailed in swing states.

Musk is currently the richest man in the world, with an estimated wealth of more than US$250 billion. But the amount of donations he said was also staggering.

According to reports, the largest known campaign donation in 2024 to date is $50 million, donated by the great-grandson of banker Thomas Mellon to support one of Trump’s super political action committees.

According to documents submitted on the 15th, as of June 30, the U.S. Political Action Committee received a total of US$8.75 million in donations. A person familiar with the matter said Musk said he plans to start donating in July.

The report also said that Musk officially expressed support for Trump shortly after the shooting. He posted on social platform X: The last time a presidential candidate encountered such a severe test was Theodore Roosevelt. (Compiled by Pan Xiaoyan)

　　Winter is coming, and many friends in the south are estimated to be inseparable from the company of air conditioning. Recently, some netizens who are familiar with the home appliance industry have summed up 10 cold knowledge about air-conditioning electric auxiliary heating. If you are afraid of cold, you may be able to learn it.Actually, it’s not just this reason, rv air conditioner Its own advantages are also obvious, and it is normal for the market to perform well. https://puremind.com/product-category/puremind-air-conditioner/rv-air-conditioner/

　　1. 38≧: According to the standard, the air outlet temperature should reach above 38≧ when air conditioning is heating, which is higher than human body temperature, otherwise it will feel like cold air when blowing on people.

　　2, wind speed: air conditioning heating, high wind speed when the outlet temperature is low, low wind speed when the outlet temperature is high.

　　3. Temperature: After the air conditioner is turned on for heating, the air outlet temperature of 40≧ is faster than that of 60≧. Because the hot air floats up, the high temperature of the outlet air will float up to the roof faster, and the lower temperature will help the middle and lower air to heat up.

　　Comprehensive 2 and 3, if the air conditioner wants to heat well, it needs to turn on the large air volume, and after turning it on, the air will be discharged at 40≧ first, and then the air will be heated to about 50≧ after the room temperature rises.

　　4. The purpose of electric auxiliary heat: it is to heat the air outlet temperature. When the outdoor temperature decreases, the heating performance of the air conditioner will be attenuated. Turning on electric auxiliary heat can increase the air outlet temperature and avoid people feeling cold wind blowing.

　　5. When do you need to turn on the auxiliary heating? According to the national standard, when the outdoor temperature is above 0≧, the auxiliary heating of air conditioner is turned off by default, and users can turn it on manually. When the temperature is lower than 0≧, it is turned on by default, and the user can turn it off manually.

　　6. Principle of electric auxiliary heating: The electric auxiliary heating is at the lower end of the internal heat exchanger, in front of the air outlet of the air conditioner, with PTC ceramic heating rods inside and aluminum fins outside. After electric auxiliary heating, the temperature will reach 200~300≧, so electric auxiliary heating can’t be dry-burned, and the air conditioner must be blown after it is turned on.

　　7. Will electric auxiliary heating blow white powder? The consultant learned that in 2024, the air-conditioning models were sold, and the sleeve pieces had been passivated, or Teflon coating was sprayed on the surface to prevent white powder blowing. At present, the models on sale will not have the problem of blowing white powder.

　　8. When defrosting the air conditioner, can you turn on the electric auxiliary heat to avoid excessive cooling of the room?

　　No way. When the air conditioner is defrosting, the internal fan stops running, and the air conditioner does not give out air. If the electric auxiliary heat is turned on, it will dry up and may burn out the internal machine parts. When the air conditioner is defrosting, it is not good for the internal machine to keep blowing air.

　　9. Air conditioners that do not stop defrosting. When some models defrost, the internal heat exchanger will heat up. Is the electric auxiliary heating turned on?

　　No, electric auxiliary heating can only heat the outlet air temperature, but not the heat exchanger.

　　10. Japanese air conditioners are good at heating without electricity, but domestic air conditioners are not good at heating with electricity.

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According to a report by TASS on July 16, a senior Republican official attending the Republican National Convention told TASS reporters that Trump was prepared to hold a dialogue with Russian President Vladimir Putin on resolving the Russia-Ukraine conflict without any middleman.

The report said that when answering a question about whether Republican presidential candidate Trump was prepared to start a dialogue with Putin on the Ukraine issue, the senior Republican Party official stressed: There is no doubt that he will start a dialogue with Putin, and there will be no middleman.

He said: Right now, the Democratic Party is not engaged in any negotiations with Russia. Of course, one person should start negotiations so that you (Russia and Ukraine) can reach some kind of agreement. When asked if the person was Trump, he gave an affirmative answer.

The senior Republican official believes that NATO should not appear in Ukraine and that the conflict should be resolved through negotiations. He said: NATO should not be present in Ukraine. There is a need for dialogue, and if dialogue opens, we can reach an agreement on how to resolve the (Ukraine) conflict.

According to reports, Russian Presidential Press Secretary Peskov emphasized that Russia remains open to any dialogue on Ukraine issues, including dialogue involving intermediaries, provided that Russia’s own goals must be achieved. On June 14, Russian President Vladimir Putin proposed conditions for mediating the situation in Ukraine, including the withdrawal of Ukrainian troops from places such as Donbas and Zaporozhye, and Kiev’s abandonment of joining NATO. In addition, Russia believes that the West should lift all sanctions against Russia and establish Ukraine’s non-aligned and non-nuclear status. (Compiled by Zhu Lifeng)

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　　Not only will it increase electricity consumption,

　　It may even affect your health.

　　Today, follow the Shanghai Health Promotion Center.

　　Let’s learn the “cold knowledge” of air conditioning use ~

　　Don’t “open and close for a while”

　　I wonder if you have had such an experience?

　　Caught in the strange circle of air conditioning turning on cold and turning off hot, repeated operation is always “cutting suitable”; Or go out and get a courier, thinking that it is more energy-saving to turn off the air conditioner first.

　　In fact, often this behavior of frequently starting the air conditioner increases the power consumption and is not conducive to the maintenance of the air conditioner.

　　Studies have proved that air conditioning “turns on and off for a while” does not actually save electricity. Therefore, if you only go out for a short time, you don’t have to turn off the air conditioner and turn it on again.

　　Pay attention to “humidity” and “temperature”

　　The muggy air has a high humidity, so it is uncomfortable to adjust the temperature. At this time, try to turn on the “dehumidification mode” after air conditioning refrigeration, and the air will become more refreshing and comfortable.

　　If you need to stay in an air-conditioned room for a long time, remember to drink water properly to avoid the loss of water.

　　Practice has proved that it is most appropriate to control the indoor and outdoor temperature difference at 6-8≧, mainly to reduce the burden on the thermoregulation center and avoid the symptoms of dizziness, headache and dry skin and mucosa. Therefore, the air conditioning temperature is set at 26 to 28≧.

　　Don’t sweat and rush into the air-conditioned room.

　　In hot summer, it is easy to sweat when you move a little and bask in the sun. Do you just want to rush into the air-conditioned room? At this time, you should be careful that the disease will come to you.

　　For the general population, sudden cold and heat are easy to catch a cold, have a fever and have diarrhea; It is even more dangerous for patients with hypertension and coronary heart disease.

　　The cardiovascular system in the original thermal environment is in a state of relaxation, and the sudden cooling air after entering the air-conditioned room makes the blood vessels contract urgently, which is prone to dangerous situations such as myocardial infarction.

　　Therefore, don’t rush into the air-conditioned room after sweating, let the sweat collect first, or wipe your body with a dry towel first. When the air conditioner is just turned on, it should not be adjusted to a too low temperature, and at the same time, it should avoid cold air blowing directly on the head, neck and waist and abdomen.

　　Do a good job cleaning

　　The cleaning problem of air conditioning is often easily overlooked, and the bacteria hidden in it will take advantage of the opportunity to cause “air conditioning disease.”

　　Legionella, which lurks in the daily artificial water environment, is such a pathogen. Water contaminated by bacteria can be inhaled by human body in the form of aerosol. After people are infected with Legionella, there will be symptoms similar to pneumonia, such as high fever, chills, fatigue, muscle pain, etc., which may even be life-threatening.

　　The air conditioning system is the main “hiding point” of Legionella, so it is necessary to clean and disinfect the air conditioning; If it is a central air conditioner, the deposited cooling tower water should be replaced and the attached “dirty things” should be removed in time. Don’t forget to clean the casing and filter screen after the “air conditioning season”.

　　In addition, it is recommended to open the window for ventilation every 2-3 hours to ensure the cleanliness of indoor air.

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According to a report by the Russian satellite news agency on March 14, the Russian National Guard announced on its Telegraph channel that the Russian National Guards, soldiers and FSB border guards fought a battle with members of the Ukrainian sabotage and reconnaissance team that were trying to sneak into Kursk.

Reported that the Russian National Guard released the news that: the Russian National Guard forces involved in repelling the enemy sabotage and reconnaissance team in the Kursk Prefecture near the town of Chotkino attack.

The governor of Kursk state, Roman Starrovoit, reported at around 11:45 Moscow time that the saboteurs were attempting to infiltrate.

Related news recommendations:

One Russian was killed when he was attacked for three days before the election.

According to Agence France-Presse, March 14, officials said that one person was killed and six injured in a drone attack on the evening of the 13th in a region bordering Russia and Ukraine. This is the third night of drone attacks on Russian territory.

Reported that the Russian Defense Ministry said that 14 Ukrainian drones were destroyed at night, which is the latest round of attacks on Russian territory before the Russian presidential election on March 15-17. Russian President Vladimir Putin is expected to win the election again.

Viaceslav Gladkov, governor of Belgorod, wrote in the Telegraph software: a civilian was killed. The man was driving when a shell hit his engine. He died on the spot of his injuries.

Gladkov said the airstrikes also destroyed two houses and one medical facility.

On the night of the 13th, 11 drones were shot down in the Belgorod region and three in the Kursk region, the Russian Defense Ministry said in a statement. (compiled by Lu Di)

German media: Ukraine systematically attacks Russian oil facilities with drones

Ukraine is systematically attacking Russian oil facilities with drones and achieving results again, German news television channel reported on March 13.

It is reported that three drones caused a fire at an oil refinery in Liangzan prefecture southeast of Moscow. The new Shahjinsk oil refinery in Rostov-upon-Don was also attacked. The latter is reported to be the largest oil refiner in southern Russia.

A source from Ukraine’s State Security Service told the Ukrainian newspaper Truth: we are systematically implementing a well-planned strategy to weaken the economic potential of the Russian Federation. Our task is to deprive the enemy of resources. He said the military’s fuel supply and Russia’s oil revenue for the war would be affected.

Reported that Ukraine hopes that the continued crackdown on Russian oil facilities can significantly reduce Russia’s fuel production. “Spring sowing in Russia will become very difficult, which means food prices will rise sharply,” former Deputy Minister of Internal Affairs Andr é Graschenko wrote on social platform X. Fuel shortages may also push up the prices of other commodities, he said.

A total of 58 Ukrainian drones were shot down by Russian air defense systems from midnight to early morning on March 13, the Russian Defense Ministry said. So far, however, the Russian military does not seem to have found a way to deal with Ukraine’s constantly developing and upgrading drones.

Itar-Tass quoted Kremlin spokesman Peskov as saying on the 12th: our soldiers are taking all necessary measures. He said that the air defense system is operating effectively, and whether the protection of industrial targets should be strengthened is a question to be answered by the Ministry of National Defense.

Putin said in an interview that the attacks are aimed at interfering with the upcoming presidential election. (compiler Wang Ting

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According to a report by the Russian News Agency on March 20, Russian law enforcement sources revealed that a man was sentenced and expelled from Russian citizenship by the Krasnodar District Court for spreading military-related rumors.

Reports said that in July 2023, Russian Alexander Somryakov was sentenced to six years in prison for deliberately spreading false information about the Russian army. The man posted a post on social networks about Russian troops suspected of committing crimes in Mariupol and other places.

Somryakov pleaded guilty to some facts at a trial in July last year, saying he knew that the information released was false. But he wanted the information to be tried by the public and to attract traffic.

The report pointed out that before this, there had been no cases of convictions and revocation of citizenship in Russia under the Criminal Code.

In October 2023, the “The Russian Federation Citizenship Law” came into effect, which includes a system of cancellation of nationality. Offences against public and personal security are one of the grounds for being convicted of revocation of nationality. At the same time, the decision to revoke nationality is not affected by the time of the crime, the date of sentence and the date of naturalization. (Compiled by Li Ran)

　　Central air conditioning is an indispensable energy consumption operation system in modern buildings. Central air conditioning system not only provides people with comfortable living and working environment, but also consumes a lot of energy. According to statistics, the energy consumption of buildings in China accounts for about 30% of the total energy consumption. In buildings with central air conditioning, the energy consumption of central air conditioning accounts for about 70% of the total energy consumption, and it is increasing year by year. Therefore, how to efficiently use the energy and energy saving of central air conditioning system has become an urgent problem to be solved.consequently Puremind Split Air Conditioners I also got a lot of attention and wanted to join the ranks. https://puremind.com/puremind-hot-sale/

　　The normal operation of the central air conditioning system, its energy consumption mainly has two aspects [1″ target=_blank>: on the one hand, it is the energy consumption of cold and heat sources to supply air handling equipment with cold and heat; On the other hand, in order to transport air and water, fans and pumps need energy to overcome the flow resistance. The energy consumption of central air conditioning system is affected by many factors, and many operation links have energy-saving measures. Therefore, energy-saving of central air conditioning is a comprehensive project. The following introduces several commonly used energy-saving measures in terms of energy consumption of cold and heat sources and power consumption.

　　1. Energy-saving measures for cold and heat sources

　　1.1 Temperature and humidity control

　　From the air treatment process of central air conditioning system, it can be seen that the lower the indoor temperature and relative humidity in summer, the greater the energy consumption of system equipment; The higher the indoor temperature and relative humidity in winter, the greater the energy consumption of the system equipment, and the corresponding initial investment and operating costs also increase.

　　Because everyone’s requirements for comfort are very different, there can be a wider comfort zone for civil central air conditioning. In this comfort zone, when cooling in summer, take a higher temperature and humidity value; When heating in winter, a certain energy-saving effect can be obtained by taking a lower temperature and humidity value. The change of temperature and humidity in the building is closely related to building energy saving. According to empirical statistics, if the set temperature is lowered by 1≧ in summer, the energy consumption will increase by 9%. If the set temperature is raised by 1≧ in winter, the energy consumption will increase by 12%. Therefore, it is an effective measure to control the temperature and humidity in the building within the precision range of the set value.

　　In order to reduce energy consumption, the indoor temperature and humidity base of air-conditioned rooms should be raised as much as possible in summer and lowered as much as possible in winter under the condition of meeting production needs and human health. At present, some owners blindly pursue the realm of “cold enough” and greatly improve the design standard of indoor temperature and humidity, which not only wastes a lot of energy unnecessarily, but also produces the negative effect of comfort.

　　The higher the temperature and humidity control precision of air conditioning system, the better the comfort and the more obvious the energy-saving effect. The accuracy of the signal measured by the front end of the air conditioning system directly affects the precise control degree of the central air conditioning system. Therefore, the measured signals, especially analog signals such as temperature and humidity, must be as accurate as possible.

　　Also, BAS with high control accuracy must be selected to control the central air conditioner. Because BAS uses DDC (Direct Digital Controller) to directly control the opening of electric water valve without intermediate regulator; In addition, DDC contains a wealth of calculation and control software, such as PID algorithm, fuzzy control algorithm, genetic algorithm and so on, to ensure the control accuracy.

　　1.2 cold source efficiency control

　　The performance index to evaluate the refrigeration efficiency of cold source is COP (Coefficient Of Performance). Refrigeration coefficient refers to the amount of cold energy that can be obtained per unit power consumption. The refrigeration coefficient has nothing to do with the nature of refrigerant, but only depends on the temperature T0 of the cooled object and the coolant temperature Tk. The higher T0, the lower Tk and the higher the refrigeration coefficient. So don’t make the chilled water temperature too low and the cooling water temperature too high during the actual operation of the air conditioning system, otherwise the refrigeration coefficient will be low, which will consume a lot of work and high power consumption to produce unit cooling capacity, and increase the energy consumption of the building. The following measures can be taken to improve the efficiency of cold source:

　　1) reduce the cooling water temperature

　　The lower the cooling water temperature, the higher the refrigeration coefficient of the cooler. For every 1≧ increase in the supply temperature of cooling water, the COP of the chiller decreases by nearly 4%. To reduce the temperature of cooling water, it is necessary to strengthen the operation management of cooling tower. First of all, for the cooling tower that stops running, the valves in and out of the water pipes should be closed. Otherwise, because the water temperature from the stopped cooling tower is high, the temperature of the mixed cooling water will increase and the refrigeration coefficient of the cooler will decrease. Secondly, after the cooling tower is used for a period of time, it should be overhauled in time, otherwise the efficiency of the cooling tower will decrease and the cooling water cannot be fully cooled.

　　2) increase the temperature of chilled water.

　　The higher the temperature of chilled water, the higher the refrigeration efficiency of the chiller. When the temperature of chilled water supply is increased by 1≧, the refrigeration coefficient of the chiller can be increased by 3%, so don’t blindly reduce the temperature of chilled water in daily operation. First of all, don’t set the set temperature of chilled water of the cold machine too low. Secondly, the water valve of the stopped chiller must be closed to prevent some chilled water from taking the bypass pipeline, otherwise, the amount of water passing through the running chiller will be reduced, resulting in the temperature of chilled water being lowered to a too low level by the chiller.

　　2. Energy-saving measures for power consumption

　　2.1 Transportation energy consumption control

　　Power consumption mainly refers to the electric energy consumed by fans and pumps in system operation. Calculation formula of input power from fan and water pump:

　　(1) (W): input power; : volume flow; : indenter; Eta: efficiency

　　From Formula (1), it can be seen that reducing power consumption can be considered from the following three aspects: reducing flow, reducing system resistance and improving the efficiency of fans and pumps. The following measures can be adopted in engineering practice:

　　1) adopt large temperature difference.

　　If the temperature difference between the supply and return water (or the return air) used to transport cold and hot water (or air) in the system is large, then when the ratio between it and the original temperature difference is m, it is known from the flow calculation formula that the flow rate is reduced to 1/m3 when the large temperature difference is used. At this time, the power required by the water pump or fan will be reduced to 1/m3. It can be seen that the energy-saving effect of increasing the temperature difference is obvious.

　　On the premise of meeting the requirements of central air conditioning accuracy, personnel comfort and technology, the temperature difference of air supply should be increased as much as possible. It should be noted that the temperature difference between supply and return water should not be greater than 8≧.

　　2) choose low flow rate.

　　Because the power consumption required by pumps and fans is roughly proportional to the flow velocity in the pipeline system, in order to achieve energy-saving operation effect, high flow velocity should not be adopted in design and operation. In addition, the low flow rate in the main pipe is also beneficial to the stability of the hydraulic condition of the system. For example, changing the rotational speed of the fan can change the performance parameters of the fan. The power of the fan has a cubic relationship with the rotational speed, while the flow rate has a linear relationship with the rotational speed. Lowering the rotational speed can greatly reduce the energy consumption while reducing the flow rate. When the flow rate is reduced by 1/3, the energy consumption can be reduced by about 70.4%, and when the flow rate is reduced by 1/2, the energy consumption can be reduced by about 87.5%, and the efficiency of the fan is basically unchanged, and it can still work stably and efficiently.

　　3) adopt energy-carrying medium with high conveying efficiency.

　　Under normal circumstances, the energy consumption of transporting cold and heat energy with water is less than that with air, and the diameter of water pipes used to transport the same cold and heat energy is much smaller than that of air pipes, which occupies a much smaller building space. This is also one of the main reasons for the rapid development of central air conditioning in recent years.

　　Therefore, for the centralized refrigeration mode, in principle, the chilled water prepared by the equipment in the computer room should be transported as far as possible to the vicinity or use point of each central air-conditioning partition, and the air should be treated by the terminal non-independent central air-conditioning units (such as cabinet air-conditioning units and fan coils) for local use or for use in nearby rooms.

　　2.2 VAV system control

　　VAV system is an energy-saving countermeasure against the shortcomings of power consumption in air supply system. VAV system can be divided into two types: one is AHU！VAV system of air conditioner; One is the indoor fan variable air volume system (FCU-VAV system) in FCU system. AHU-VAV system is to fix the air supply temperature in the whole air duct system and adjust the air supply volume of the blower to cope with the change of indoor air conditioning load. In FCU-VAV system, the cold water supply is fixed, and the indoor FCU is equipped with a stepless power controller to change the air supply, that is, to change the heat exchange rate of FCU to adjust the indoor load change. These two methods can reduce the power consumption of the blower by adjusting the air volume, and at the same time, they can also increase the operating efficiency of the heat source machine and save the power consumption of the heat source, so they can achieve energy-saving effects in both air supply and heat source.

　　The cooling capacity sent into the room can be determined by the following formula:

　　2

　　Where: c is the specific heat capacity of air, kj/(kg≧); ρ is the air density, Kg/m3; L is the air supply volume, m3/S; Tn is the indoor temperature,≧; Ts is the supply air temperature,≧; Q is the heat absorbed (or put) into the room, KW.

　　If the air supply temperature is set as a constant and the air supply volume L is changed, different Q values can be obtained to keep the room temperature unchanged. Variable air volume control can adopt an air supply device that automatically adjusts the air supply volume according to the change of indoor load. When the indoor load decreases, it can keep the air supply parameters unchanged (no need to reheat) and keep the indoor temperature stable by automatically reducing the air volume. In this way, it can not only save the reheat required by the constant air volume system to increase the air supply temperature, but also reduce the power consumption of the fan and the cooling capacity of the refrigerator due to the reduction of the treated air volume. According to various data, VAV can save energy by 30% ~ 50% compared with constant air volume.

　　2.3 Frequency conversion control

　　In most buildings, the central air conditioning is at the maximum load only for a few days in a year. The cooling load of central air conditioning is always changing dynamically, such as the changes of various factors such as morning and evening, climate, passenger flow and activity content, which affect the cooling load of central air conditioning in real time. Generally, the cooling load fluctuates in the range of 5 ~ 60%, and most buildings are at least 70% in this situation every year. However, most central air conditioners are driven by maximum cooling load and maximum power due to system design. In this way, the contradiction between the actual cooling load and the maximum power output is caused, resulting in a huge waste of energy. This contradiction can be solved by adopting frequency conversion control.

　　1) Fan and water pump frequency conversion control

　　In the past, the AC motor itself didn’t adjust the speed, so the central air conditioning system had to rely on baffles and valves to adjust the air and water flow, and a lot of electric energy was wasted on baffles and valves. If the fan water pump is regulated by frequency conversion, the energy wasted on baffles and valves will be saved, and the average energy saving effect of each pump will be considerable.

　　For the fan water pump, according to the principle of fluid mechanics, the parameters under similar working conditions have the following relationship [2″ target=_blank>:

　　3

　　Where Q1, H1, n1 and N1 are the flow, lift, power and rotation speed before the rotation speed change, respectively;

　　Q2, H2, n2, N2: the flow, lift, power, and rotation speed after the rotation speed is changed respectively.

　　According to Formula (3), the flow rate is proportional to the rotational speed, the pressure is proportional to the square of the rotational speed, and the power consumed is proportional to the cubic power of the rotational speed. For variable frequency speed regulation, the speed n is basically proportional to the power frequency f, when the power frequency f decreases, the motor speed also decreases, and the required power decreases rapidly with the cubic power of the speed, which shows that the energy-saving effect is very remarkable. Take the fan as an example, if the required air volume is 80% of the rated air volume, the speed will also drop to 80% of the rated speed, and the shaft power will drop by 51.2%; When the required air volume is 50% of the rated air volume, the shaft power drops by 12.5%. This power saving effect is also very impressive. It has been proved that the frequency conversion control of fans and pumps can save energy by 40% ~ 50%.

　　2) Frequency conversion control of water chillers

　　Because the compressor does not rule out the possibility of long-term operation under full load, the capacity of the motor can only be determined according to the maximum demand, so the design margin is generally large. In actual operation, the proportion of light load operation time is very high. Frequency conversion control is adopted to adjust the speed of compressor, so as to control the refrigeration capacity and keep the refrigeration unit in the best (most reasonable) operation state. Frequency conversion control improves the efficiency of air conditioner and the operation effect of refrigeration unit, thus realizing energy saving.

　　The principle of variable frequency compressor is to adjust the displacement of compressor per unit time by adjusting the speed of compressor, so as to achieve the purpose of adjusting the refrigeration capacity. The mathematical relationship between refrigeration capacity and compressor frequency is as follows:

　　4

　　Where n is the rotational speed, f is the frequency of the motor, p is the polar logarithm of the motor, s is the slip of the motor, λ is the leakage coefficient, Ps is the suction pressure, vh is the suction volume, ni is the polytropic index, εi is the pressure ratio (exhaust/suction), δ0 is the relative pressure loss coefficient, and Zs and Zd are the actual gas compressibility coefficients, which are the average energy efficiency ratio.

　　According to Formula (4), the refrigeration capacity is directly proportional to the frequency, so the refrigeration capacity can be controlled by frequency conversion regulation, thus achieving the energy-saving effect.

　　Some adjustment methods (such as adjusting the valve opening and changing the blade angle) can not reduce the operating efficiency of the motor even if the demand is small. After adopting frequency conversion speed regulation, when the demand is small, the speed of motor can be reduced and the running power of motor can be reduced, thus further realizing energy saving. It has been proved that the frequency conversion control of water chillers can save energy by 20% ~ 30%.

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[A man in Kenya is suspected of murdering 42 women and dismembering and dumping their bodies in slums, including his wife” target=_blank>

On July 15, Kenyan police said they had arrested a man suspected of murdering 42 women and dumping their bodies in a slum. The man is suspected of killing 42 women, including his wife, starting in 2022.

Police said they had received a report from the family of one of the missing women and found the remains of nine people in the slum on the 13th.

On the 15th, police arrested the man near a bar in Nairobi, saying that the man lived only 100 meters away from where the remains were found. Police also found knives, nylon bags, rope, industrial gloves, women’s handbags and women’s underwear at the man’s residence.

Police are currently conducting further investigations into the man.

　　Central air conditioning is an indispensable energy consumption operation system in modern buildings. Central air conditioning system not only provides people with comfortable living and working environment, but also consumes a lot of energy. According to statistics, the energy consumption of buildings in China accounts for about 30% of the total energy consumption. In buildings with central air conditioning, the energy consumption of central air conditioning accounts for about 70% of the total energy consumption, and it is increasing year by year. Therefore, how to efficiently use the energy and energy saving of central air conditioning system has become an urgent problem to be solved.Now, everyone is right commercial air conditioner units? Are more concerned, hoping to get more benefits from it. https://puremind.com/product-category/puremind-air-conditioner/commercial-air-conditioner/

　　The normal operation of the central air conditioning system, its energy consumption mainly has two aspects [1″ target=_blank>: on the one hand, it is the energy consumption of cold and heat sources to supply air handling equipment with cold and heat; On the other hand, in order to transport air and water, fans and pumps need energy to overcome the flow resistance. The energy consumption of central air conditioning system is affected by many factors, and many operation links have energy-saving measures. Therefore, energy-saving of central air conditioning is a comprehensive project. The following introduces several commonly used energy-saving measures in terms of energy consumption of cold and heat sources and power consumption.

　　1. Energy-saving measures for cold and heat sources

　　1.1 Temperature and humidity control

　　From the air treatment process of central air conditioning system, it can be seen that the lower the indoor temperature and relative humidity in summer, the greater the energy consumption of system equipment; The higher the indoor temperature and relative humidity in winter, the greater the energy consumption of the system equipment, and the corresponding initial investment and operating costs also increase.

　　Because everyone’s requirements for comfort are very different, there can be a wider comfort zone for civil central air conditioning. In this comfort zone, when cooling in summer, take a higher temperature and humidity value; When heating in winter, a certain energy-saving effect can be obtained by taking a lower temperature and humidity value. The change of temperature and humidity in the building is closely related to building energy saving. According to empirical statistics, if the set temperature is lowered by 1≧ in summer, the energy consumption will increase by 9%. If the set temperature is raised by 1≧ in winter, the energy consumption will increase by 12%. Therefore, it is an effective measure to control the temperature and humidity in the building within the precision range of the set value.

　　In order to reduce energy consumption, the indoor temperature and humidity base of air-conditioned rooms should be raised as much as possible in summer and lowered as much as possible in winter under the condition of meeting production needs and human health. At present, some owners blindly pursue the realm of “cold enough” and greatly improve the design standard of indoor temperature and humidity, which not only wastes a lot of energy unnecessarily, but also produces the negative effect of comfort.

　　The higher the temperature and humidity control precision of air conditioning system, the better the comfort and the more obvious the energy-saving effect. The accuracy of the signal measured by the front end of the air conditioning system directly affects the precise control degree of the central air conditioning system. Therefore, the measured signals, especially analog signals such as temperature and humidity, must be as accurate as possible.

　　Also, BAS with high control accuracy must be selected to control the central air conditioner. Because BAS uses DDC (Direct Digital Controller) to directly control the opening of electric water valve without intermediate regulator; In addition, DDC contains a wealth of calculation and control software, such as PID algorithm, fuzzy control algorithm, genetic algorithm and so on, to ensure the control accuracy.

　　1.2 cold source efficiency control

　　The performance index to evaluate the refrigeration efficiency of cold source is COP (Coefficient Of Performance). Refrigeration coefficient refers to the amount of cold energy that can be obtained per unit power consumption. The refrigeration coefficient has nothing to do with the nature of refrigerant, but only depends on the temperature T0 of the cooled object and the coolant temperature Tk. The higher T0, the lower Tk and the higher the refrigeration coefficient. So don’t make the chilled water temperature too low and the cooling water temperature too high during the actual operation of the air conditioning system, otherwise the refrigeration coefficient will be low, which will consume a lot of work and high power consumption to produce unit cooling capacity, and increase the energy consumption of the building. The following measures can be taken to improve the efficiency of cold source:

　　1) reduce the cooling water temperature

　　The lower the cooling water temperature, the higher the refrigeration coefficient of the cooler. For every 1≧ increase in the supply temperature of cooling water, the COP of the chiller decreases by nearly 4%. To reduce the temperature of cooling water, it is necessary to strengthen the operation management of cooling tower. First of all, for the cooling tower that stops running, the valves in and out of the water pipes should be closed. Otherwise, because the water temperature from the stopped cooling tower is high, the temperature of the mixed cooling water will increase and the refrigeration coefficient of the cooler will decrease. Secondly, after the cooling tower is used for a period of time, it should be overhauled in time, otherwise the efficiency of the cooling tower will decrease and the cooling water cannot be fully cooled.

　　2) increase the temperature of chilled water.

　　The higher the temperature of chilled water, the higher the refrigeration efficiency of the chiller. When the temperature of chilled water supply is increased by 1≧, the refrigeration coefficient of the chiller can be increased by 3%, so don’t blindly reduce the temperature of chilled water in daily operation. First of all, don’t set the set temperature of chilled water of the cold machine too low. Secondly, the water valve of the stopped chiller must be closed to prevent some chilled water from taking the bypass pipeline, otherwise, the amount of water passing through the running chiller will be reduced, resulting in the temperature of chilled water being lowered to a too low level by the chiller.

　　2. Energy-saving measures for power consumption

　　2.1 Transportation energy consumption control

　　Power consumption mainly refers to the electric energy consumed by fans and pumps in system operation. Calculation formula of input power from fan and water pump:

　　(1) (W): input power; : volume flow; : indenter; Eta: efficiency

　　From Formula (1), it can be seen that reducing power consumption can be considered from the following three aspects: reducing flow, reducing system resistance and improving the efficiency of fans and pumps. The following measures can be adopted in engineering practice:

　　1) adopt large temperature difference.

　　If the temperature difference between the supply and return water (or the return air) used to transport cold and hot water (or air) in the system is large, then when the ratio between it and the original temperature difference is m, it is known from the flow calculation formula that the flow rate is reduced to 1/m3 when the large temperature difference is used. At this time, the power required by the water pump or fan will be reduced to 1/m3. It can be seen that the energy-saving effect of increasing the temperature difference is obvious.

　　On the premise of meeting the requirements of central air conditioning accuracy, personnel comfort and technology, the temperature difference of air supply should be increased as much as possible. It should be noted that the temperature difference between supply and return water should not be greater than 8≧.

　　2) choose low flow rate.

　　Because the power consumption required by pumps and fans is roughly proportional to the flow velocity in the pipeline system, in order to achieve energy-saving operation effect, high flow velocity should not be adopted in design and operation. In addition, the low flow rate in the main pipe is also beneficial to the stability of the hydraulic condition of the system. For example, changing the rotational speed of the fan can change the performance parameters of the fan. The power of the fan has a cubic relationship with the rotational speed, while the flow rate has a linear relationship with the rotational speed. Lowering the rotational speed can greatly reduce the energy consumption while reducing the flow rate. When the flow rate is reduced by 1/3, the energy consumption can be reduced by about 70.4%, and when the flow rate is reduced by 1/2, the energy consumption can be reduced by about 87.5%, and the efficiency of the fan is basically unchanged, and it can still work stably and efficiently.

　　3) adopt energy-carrying medium with high conveying efficiency.

　　Under normal circumstances, the energy consumption of transporting cold and heat energy with water is less than that with air, and the diameter of water pipes used to transport the same cold and heat energy is much smaller than that of air pipes, which occupies a much smaller building space. This is also one of the main reasons for the rapid development of central air conditioning in recent years.

　　Therefore, for the centralized refrigeration mode, in principle, the chilled water prepared by the equipment in the computer room should be transported as far as possible to the vicinity or use point of each central air-conditioning partition, and the air should be treated by the terminal non-independent central air-conditioning units (such as cabinet air-conditioning units and fan coils) for local use or for use in nearby rooms.

　　2.2 VAV system control

　　VAV system is an energy-saving countermeasure against the shortcomings of power consumption in air supply system. VAV system can be divided into two types: one is AHU！VAV system of air conditioner; One is the indoor fan variable air volume system (FCU-VAV system) in FCU system. AHU-VAV system is to fix the air supply temperature in the whole air duct system and adjust the air supply volume of the blower to cope with the change of indoor air conditioning load. In FCU-VAV system, the cold water supply is fixed, and the indoor FCU is equipped with a stepless power controller to change the air supply, that is, to change the heat exchange rate of FCU to adjust the indoor load change. These two methods can reduce the power consumption of the blower by adjusting the air volume, and at the same time, they can also increase the operating efficiency of the heat source machine and save the power consumption of the heat source, so they can achieve energy-saving effects in both air supply and heat source.

　　The cooling capacity sent into the room can be determined by the following formula:

　　2

　　Where: c is the specific heat capacity of air, kj/(kg≧); ρ is the air density, Kg/m3; L is the air supply volume, m3/S; Tn is the indoor temperature,≧; Ts is the supply air temperature,≧; Q is the heat absorbed (or put) into the room, KW.

　　If the air supply temperature is set as a constant and the air supply volume L is changed, different Q values can be obtained to keep the room temperature unchanged. Variable air volume control can adopt an air supply device that automatically adjusts the air supply volume according to the change of indoor load. When the indoor load decreases, it can keep the air supply parameters unchanged (no need to reheat) and keep the indoor temperature stable by automatically reducing the air volume. In this way, it can not only save the reheat required by the constant air volume system to increase the air supply temperature, but also reduce the power consumption of the fan and the cooling capacity of the refrigerator due to the reduction of the treated air volume. According to various data, VAV can save energy by 30% ~ 50% compared with constant air volume.

　　2.3 Frequency conversion control

　　In most buildings, the central air conditioning is at the maximum load only for a few days in a year. The cooling load of central air conditioning is always changing dynamically, such as the changes of various factors such as morning and evening, climate, passenger flow and activity content, which affect the cooling load of central air conditioning in real time. Generally, the cooling load fluctuates in the range of 5 ~ 60%, and most buildings are at least 70% in this situation every year. However, most central air conditioners are driven by maximum cooling load and maximum power due to system design. In this way, the contradiction between the actual cooling load and the maximum power output is caused, resulting in a huge waste of energy. This contradiction can be solved by adopting frequency conversion control.

　　1) Fan and water pump frequency conversion control

　　In the past, the AC motor itself didn’t adjust the speed, so the central air conditioning system had to rely on baffles and valves to adjust the air and water flow, and a lot of electric energy was wasted on baffles and valves. If the fan water pump is regulated by frequency conversion, the energy wasted on baffles and valves will be saved, and the average energy saving effect of each pump will be considerable.

　　For the fan water pump, according to the principle of fluid mechanics, the parameters under similar working conditions have the following relationship [2″ target=_blank>:

　　3

　　Where Q1, H1, n1 and N1 are the flow, lift, power and rotation speed before the rotation speed change, respectively;

　　Q2, H2, n2, N2: the flow, lift, power, and rotation speed after the rotation speed is changed respectively.

　　According to Formula (3), the flow rate is proportional to the rotational speed, the pressure is proportional to the square of the rotational speed, and the power consumed is proportional to the cubic power of the rotational speed. For variable frequency speed regulation, the speed n is basically proportional to the power frequency f, when the power frequency f decreases, the motor speed also decreases, and the required power decreases rapidly with the cubic power of the speed, which shows that the energy-saving effect is very remarkable. Take the fan as an example, if the required air volume is 80% of the rated air volume, the speed will also drop to 80% of the rated speed, and the shaft power will drop by 51.2%; When the required air volume is 50% of the rated air volume, the shaft power drops by 12.5%. This power saving effect is also very impressive. It has been proved that the frequency conversion control of fans and pumps can save energy by 40% ~ 50%.

　　2) Frequency conversion control of water chillers

　　Because the compressor does not rule out the possibility of long-term operation under full load, the capacity of the motor can only be determined according to the maximum demand, so the design margin is generally large. In actual operation, the proportion of light load operation time is very high. Frequency conversion control is adopted to adjust the speed of compressor, so as to control the refrigeration capacity and keep the refrigeration unit in the best (most reasonable) operation state. Frequency conversion control improves the efficiency of air conditioner and the operation effect of refrigeration unit, thus realizing energy saving.

　　The principle of variable frequency compressor is to adjust the displacement of compressor per unit time by adjusting the speed of compressor, so as to achieve the purpose of adjusting the refrigeration capacity. The mathematical relationship between refrigeration capacity and compressor frequency is as follows:

　　4

　　Where n is the rotational speed, f is the frequency of the motor, p is the polar logarithm of the motor, s is the slip of the motor, λ is the leakage coefficient, Ps is the suction pressure, vh is the suction volume, ni is the polytropic index, εi is the pressure ratio (exhaust/suction), δ0 is the relative pressure loss coefficient, and Zs and Zd are the actual gas compressibility coefficients, which are the average energy efficiency ratio.

　　According to Formula (4), the refrigeration capacity is directly proportional to the frequency, so the refrigeration capacity can be controlled by frequency conversion regulation, thus achieving the energy-saving effect.

　　Some adjustment methods (such as adjusting the valve opening and changing the blade angle) can not reduce the operating efficiency of the motor even if the demand is small. After adopting frequency conversion speed regulation, when the demand is small, the speed of motor can be reduced and the running power of motor can be reduced, thus further realizing energy saving. It has been proved that the frequency conversion control of water chillers can save energy by 20% ~ 30%.