WO2010066076A1

WO2010066076A1 - Energy saving air-conditioning control system based on predicted mean vote and method thereof

Info

Publication number: WO2010066076A1
Application number: PCT/CN2008/073429
Authority: WO
Inventors: 程朋胜; 裴念强; 李铁牛; 郭宇红; 李信洪
Original assignee: 深圳达实智能股份有限公司
Priority date: 2008-12-10
Filing date: 2008-12-10
Publication date: 2010-06-17
Also published as: CN101828082B; CN101828082A

Abstract

An energy saving air-conditioning control system based on the Predicted Mean Vote (PMV), includes a controller (101), a PMV sensor (107), a CO2 concentration sensor (109), an outdoor enthalpy value sensor (102), an indoor enthalpy value sensor (108), a fresh air valve (103), a coil pipe cool water valve (104), and a fan transducer (106). The controller (101) includes PMV control module (302), an energy saving control module (303). The PMV sensor (107), the CO2 concentration sensor (109), the indoor enthalpy value sensor (108), the outdoor enthalpy value sensor (102) are connected to an analog input electric circuit (304) of the controller (101). The fresh air valve (103), the cool water valve (104) and the fan transducer (106) are connected to the output electric circuit (305) of the controller (101). This application also discloses a control method for the control system.

Description

Air conditioner energy-saving control system and method based on average thermal sensation index

[1] The present invention relates to an air conditioning control system, and more particularly to an air conditioning energy saving control system and method based on an estimated average thermal sensation index.

Background technique

[2] With the improvement of living standards, people pay more and more attention to environmental quality. For people living in the city, most of the daytime is in a closed indoor air-conditioning environment. From the perspective of physical health and work efficiency, it is very important to ensure indoor thermal comfort and air quality. At the same time, energy conservation has become China's basic national policy due to energy shortages and environmental degradation. However, to ensure indoor thermal comfort and air quality, it is often at the expense of energy consumption and operating costs of air conditioning systems.

[3] At present, in the comfort air conditioning system, most of the indoor temperature is the control scheme of the controlled parameters. but

In addition to the indoor air temperature, the comfortable environment required by the human body is also affected by various factors such as indoor air humidity, air flow speed, and indoor air quality. In 1984, the International Organization for Standardization (ISO) proposed a standardized method for indoor thermal environment assessment and measurement (IS07726), which was described and evaluated using the expected average thermal sensation index PMV, which is based on the thermal balance between the human body and the environment, including The warm environment indicators of six factors: temperature, humidity, radiation, airflow, and human metabolism and clothing. The thermal and thermal scale corresponding to the PM V value is as follows:

In indoor air, carbon dioxide is below 700PPM, which is clean air. The human body feels good. When the concentration is 700~1000PPM, it belongs to ordinary air. Individual sensitive people will feel bad smell. It is stipulated in China's "Sanitary Standards for Indoor Air Carbon Dioxide". The air quality standard for carbon dioxide content is 1000 P PM. Therefore, simply controlling the indoor temperature is difficult to create a truly comfortable indoor environment. Even a more comfortable indoor environment can result in increased energy and operating costs for the air conditioning system.

[6] One solution in the prior art is to measure the indoor environmental parameters by sensors, change the refrigerant flow rate, The way the fan speed is adjusted allows the room to meet the PMV thermal comfort range. The other solution is to use two control modes. The first one is based on the PMV control of the air conditioner. When the PMV allowable range is reached, the second control mode is executed, and the air purification mode is performed according to the oxygen and carbon dioxide concentrations. The focus of these two patents is to achieve thermal comfort in the room through automatic control, but they do not consider the issue of air conditioning energy consumption.

[7] Therefore, there is an urgent need for an air conditioning control system that satisfies the needs of human comfort and ensures the lowest energy consumption of the system.

Summary of the invention

[8] The object of the present invention is to solve the problem that the above-mentioned comfort and energy saving cannot be balanced, and to provide a controlled parameter with an expected average thermal sensation index (hereinafter referred to as PMV), indoor carbon dioxide content, and indoor and outdoor enthalpy values. On the basis of satisfying indoor thermal comfort and air quality, the method of energy-saving operation of the air-conditioning system is realized by controlling the fan speed and the valve opening degree.

[9] Because the random, entangled, hysteresis and nonlinear characteristics of the control object of the air conditioning system are obvious, the traditional control methods such as PID control are not easy to achieve online adjustment of the control parameters, and the automatic adjustment ability is poor. The present invention solves the above problems by introducing a modern fuzzy control method for adjusting the range of PMV values.

[10] In the air conditioning energy saving control system according to the present invention, the system includes a controller, a PMV sensor,

C02 concentration sensor, fresh air valve, cold water valve, fan frequency converter; in an embodiment according to the invention, the system further comprises an outdoor 焓 value (HI) sensor, an indoor enthalpy (H2) sensor;

[11] The C02 concentration sensor, the indoor devaluation sensor, and the outdoor annihilation sensor are connected to the input end of the controller;

[12] The fresh air valve, the cold water valve and the fan frequency converter are connected at an output end of the controller;

[13] the controller includes adjusting an opening of the fresh air valve according to the input of the C02 concentration sensor, the indoor devaluation sensor, the outdoor devaluation sensor, and based on a set C02 concentration threshold to reduce the Energy-saving control module for energy-saving system load realization.

[14] An air conditioning energy saving control system according to the present invention, the system further comprising an estimated average thermal sensation index PMV sensor coupled to an input of the controller. Wherein, the controller further includes according to the P

The input of the MV sensor and the PMV control module that adjusts the fan frequency and the cold water valve opening based on the set PMV threshold range.

[15] In order to be able to meet comfort and energy saving requirements and indoor air quality, the present invention also provides an empty Adjusting the energy control method, the method comprising:

[16] Determine if the PMV value is within the PMV threshold, if so, do the following:

[17] In the case of cooling, set indoor and outdoor 焓 Η Η outdoor 焓 HI - indoor 焓 value H2;

[18] When ΔΗ<0吋, increase the fresh air valve opening control amount to reduce the load;

[19] When the ΔΗ>0吋, monitoring the CO 2 concentration, if the CO 2 concentration is lower than the threshold, the fresh air valve opening control amount may be appropriately reduced to reduce the load, if the CO 2 concentration Exceeding the threshold

Then, the fresh air valve opening degree control amount is appropriately increased.

[20] According to an aspect of the method of the present invention, the method further comprises performing the following operations in the case of heating

[21] when the ΔΗ>0吋, increasing the fresh air valve opening control amount to reduce the load;

[22] When the ΔΗ<0吋, monitoring the CO 2 concentration, if the CO 2 concentration is lower than the threshold, the fresh air valve opening control amount may be appropriately reduced to reduce the load, if When the C02 concentration exceeds the threshold value, the fresh air valve opening degree control amount is appropriately increased.

[23] According to another aspect of the method of the present invention, the C02 concentration threshold may be selected between 700 and 1000 ppm, and in the present invention, the C02 concentration threshold is selected to be 950 ppm.

According to the present invention, if it is determined that the PMV value is not within the PMV threshold, the method further includes the following steps:

[25] S201, PMV value set and model initialization, wherein, according to the PMV value of the PMV sensor set and the set PMV threshold range, the PMV deviation value and the PMV deviation change rate are calculated;

[26] S202, PMV deviation value fuzzification processing, wherein the PMV deviation value is calculated according to the prepared fuzzy program to calculate the fuzzy amount of the PMV deviation value;

[27] S203, PMV deviation change rate fuzzification, wherein the PMV deviation change rate is calculated according to the prepared fuzzy program to calculate the blur amount of the PMV deviation change rate;

[28] S204, fuzzy inference, wherein the fuzzy quantity of the PMV deviation value and the fuzzy quantity of the PMV deviation change rate are used as input parameters, and the fuzzy control is obtained by looking up the table in a preset fuzzy rule base.

[29] S205, blur quantity clearing processing, decomposing the fuzzy control quantity into a frequency control quantity and a cold water valve opening degree control quantity; [30] S206. Output processing, respectively outputting the obtained frequency control amount and the cold water valve opening degree control amount.

According to still another aspect of the present invention, the PMV threshold range is set between -0.5 and 0.5.

[32] The present invention uses PMV value, C02 concentration, and indoor and outdoor enthalpy difference ΔΗ as controlled parameters to ensure indoor thermal comfort and air cleanliness, and effectively improve the indoor environment. In addition, the PMV control module on the controller and the energy-saving control module optimize the control of the air conditioning unit to achieve energy savings.

DRAWINGS

1 is a diagram of an air conditioning energy saving control system in accordance with an embodiment of the present invention;

[34] Figure 2 is a graphical representation of the relationship between the projected average thermal sensation index and the percentage of expected population dissatisfaction based on the standardized method for indoor thermal environment assessment and measurement (IS07726);

3 is a block diagram showing the structure of a controller in accordance with an embodiment of the present invention;

[36] FIG. 4 is a flow chart for adjusting the opening of the fresh air valve based on the indoor and outdoor enthalpy values and the C02 concentration threshold value in accordance with the present invention that satisfies the PMV threshold range and the system is in the cooling state;

Figure 5 is a flow chart for adjusting the PMV index in a PMV control module in accordance with the present invention.

detailed description

1 shows an air conditioning energy-saving control system according to the present invention, which mainly includes a controller 101, a PMV sensor 107, a C02 concentration sensor 109, an indoor depreciation sensor 108, an outdoor depreciation sensor 102, a fresh air valve 103, and a cold water valve. 104. Fan inverter 106.

[39] 焓 is the total energy of a working fluid (here, air) in a certain state, which is the sum of internal energy U and flow energy PV, which is a composite state parameter, which is defined as H = U + PV .焓 denoted by the symbol H, and its unit is J or kJ. Because 焓 is a comprehensive quantity consisting of state parameters U, P, and V, U, P, and V have certain values for a certain state of working fluid, so the value of U + PV is completely determined. Therefore, 焓 is a state parameter that depends on the state of the working fluid, and it has all the characteristics of the state parameter. The thermodynamic energy U is the energy of the working medium itself, and the driving power is the energy transferred with the working fluid flow. Therefore, in the process of state change, the 焓 variable of the working fluid is the inflow (or outflow) of the working fluid. (or pass out) the total energy of the system. Therefore, by measuring the difference between the indoor and outdoor air enthalpy values, it can be known that when the outdoor fresh air is introduced, the energy increase or decrease in the building is increased, that is, the air conditioning load is increased or the air conditioning load is reduced. By measuring the difference between indoor and outdoor air enthalpy and controlling the amount of fresh air introduced into the room, air conditioning can be achieved. The purpose of system energy consumption.

[40] During the summer and transition seasons, air conditioning systems require cooling to maintain a comfortable indoor environment. When the outdoor air enthalpy is less than the indoor air enthalpy (ie ΔΗ<0), increasing the fresh air volume can reduce the air conditioning cooling load, which will reduce the air conditioning. The load rate of the system saves the energy consumption of the entire air conditioning system; when the outdoor air enthalpy is greater than the indoor air enthalpy (ie ΔΗ>0), the outdoor air energy is higher than the indoor air energy, and the amount of fresh air introduction needs to be minimized. On the contrary, in the case of heating in the air conditioning system in winter, when the outdoor air enthalpy is less than the indoor air enthalpy, in order to reduce the heat load of the air conditioning system, the amount of fresh air introduction is minimized to reduce the energy consumption of the air conditioning system; The value is greater than the indoor air enthalpy 吋, increasing the fresh air volume, can reduce the air conditioning load rate, thereby saving air conditioning heating energy consumption.

[41] As shown in Figure 2, it shows a standardized method based on indoor thermal environment assessment and measurement (IS07726)

In the present invention, the comprehensive energy consumption index selects the PMV threshold range of -0.5_0.5, which according to Figure 2 can satisfy the thermal comfort requirement of 90% of the population. .

[42] As shown in FIG. 3, the controller further includes a PMV control module 302, an energy saving control module 303, an analog input circuit 304, and an analog output circuit 305. A detecting unit such as the PMV sensor 107, the C02 concentration sensor 109, the indoor devaluation sensor 108, and the outdoor sniffer sensor 102 is connected to the analog input circuit 30 4 of the controller 101, and the fresh air valve 103, the cold water valve 104, and the fan inverter 106 are The control object is connected to the analog output circuit 305 of the controller 101.

[43] In the present invention, a monitoring point is selected for each air conditioning unit control area, and a PMV sensor is installed.

The C02 concentration sensor 109 and the indoor and outdoor depreciation sensors (108 and 102) are responsible for collecting the PMV value, the C02 concentration value and the threshold value in the corresponding area, and transmitting the data to 101.

[44] The frequency converter is responsible for receiving the frequency control signal Ff from the analog output circuit 305, and adjusting the output frequency of the frequency converter to control the air speed of the air conditioning unit.

[45] The cold water valve is responsible for receiving the valve opening control signal So from the analog output circuit 305, and accordingly adjusting the opening of the cold water valve 104 to control the flow of cold water entering the coil to adjust the temperature.

[46] The fresh air valve is responsible for receiving the valve opening control signal Fo from the analog output circuit 305, and accordingly adjusting the opening of the fresh air valve to control the air volume of the air conditioning unit, thereby improving the air quality.

[47] As shown in FIG. 4, according to an embodiment of the present invention, the human body comfort is satisfied when the PMV index range is satisfied. After the degree of control demand, it is more important to achieve the energy-saving purpose of the air-conditioning fan control system. Here, the fresh air valve opening degree is controlled based on the indoor and outdoor enthalpy difference ΔΗ (ie, ΔΗ outdoor 焓 value HI-indoor enthalpy H2) and the CO 2 concentration, and the method in the air conditioning system cooling state is as follows:

[48] The method starts in step 401, and then performs step 402, performs PMV measurement, determines whether the PMV is within the threshold range according to the sample value, and if yes, proceeds to step 404, and if not, executes step 405. ;

[49] In step 405, PMV control is performed until the PMV is within the threshold range.

[50] In step 404, it is judged whether or not the 焓 difference ΔΗ is less than 0. If yes, the introduction of fresh air reduces the load of the chiller, so step 408 is executed to increase the fresh air valve opening control amount Fo to increase the amount of fresh air entering the room. The step then returns to the start step 401; if not, the process proceeds to step 406.

[51] In step 406, if a new wind is introduced, the unit load will be increased. Therefore, the indoor CO 2 concentration should be monitored. If the CO 2 concentration is higher than 950 ppm, the energy consumption should be sacrificed to ensure the indoor air quality. 408, increase the fresh air valve opening control amount Fo

, after which the steps return to the beginning and the next processing is performed.

[52] If the C02 concentration is lower than 950ppm, then step 407 can be continued to reduce the valve opening control amount Fo, thereby reducing the chiller load, and then the step returns to the beginning to perform the next processing.

[53] When the air conditioning system is in the heating state, the control method is reversed, so it is not shown in the figure. The steps are as follows:

[54] When ΔΗ>0吋, the introduction of fresh air will reduce the load on the chiller, thus increasing the valve opening control. Fo

Increase the amount of fresh air entering the room; when ΔΗ<0吋, the introduction of fresh air will increase the unit load. This will monitor the indoor CO2 concentration. If the C02 concentration is lower than 950ppm吋, the valve opening control amount will be reduced. 02 concentration higher than 950ppm 吋, can not reduce the fresh air, but to sacrifice energy to ensure indoor air quality, so increase the valve opening control amount Fo, and thus repeatedly adjust the valve to achieve energy and comfort balance

[55] As shown in FIG. 5, in an embodiment of the present invention, the PMV control module is configured to control the fan frequency and the cold water valve when the PMV value exceeds the threshold range, thereby changing the indoor temperature and humidity and the wind speed, thereby adjusting the indoor The PMV value is within the threshold. The following is the PMV fuzzy control step:

[56] S201, PMV value set and model initialization, in this step, the controller according to the present invention passes P

The MV sensor collects the PMV indicator and calculates the PMV deviation value and PM according to the set PMV threshold range. V deviation change rate;

[57] S202, PMV deviation fuzzy quantization processing, in this step, the PMV deviation value is calculated according to the compiled fuzzification program, and the fuzzy quantity of the PMV deviation value is calculated;

[58] S203, PMV deviation change rate is blurred, wherein the PMV deviation change rate is calculated according to the prepared fuzzy program, and the fuzzy amount of the PMV deviation change rate is calculated;

[59] S204, fuzzy inference, in this step, the fuzzy quantity of the PMV deviation and the fuzzy quantity of the PMV deviation change rate are used as input parameters, and the fuzzy control quantity is obtained by looking up the table in a preset fuzzy rule base. The fuzzy rule base is preset and stored in the controller according to the experience obtained by the iterative adjustment system, and the fuzzy control quantity relates to multiple control objects;

[60] S205, the fuzzy quantity clearing process, because the fuzzy control quantity obtained in the fuzzy inference process is related to a plurality of control objects, and the plurality of control objects are deeply coupled, according to the present invention, the fuzzy control quantity is decomposed according to the program for the sake of brevity The two separate control quantities, the frequency control amount Ff and the cold water valve opening control amount Soo can be decomposed into more individual control quantities in different applications;

[61] S206. Output processing, respectively outputting the obtained individual control quantities to different control objects, such as an inverter, a water valve, and the like.

[62] Wherein in the embodiment of the present invention, since the fuzzy rule base is composed of empirical data obtained by a technician in actual control operations according to air conditioning and environmental characteristics, in other cases, the fuzzy rule base may be different. .

[63] The present invention realizes the adjustment of the environmental PMV by fuzzy control and achieves the improvement of the air quality by monitoring the concentration of C02, and the optimal combination of the thermal comfort requirements and the energy saving requirements of the system can be realized according to the embodiment of the present invention.

Claims

Claim

[1] An air conditioning energy-saving control system based on an estimated average thermal sensation index,

The controller includes a controller, a C02 concentration sensor, a fresh air valve, a cold water valve, and a fan frequency converter. The system further includes an outdoor depreciation sensor and an indoor depreciation sensor; the C02 concentration sensor and the indoor depreciation sensor. The outdoor devaluation sensor is connected to an input end of the controller;

The fresh air valve, the cold water valve and the fan frequency converter are connected at an output end of the controller;

The controller includes adjusting an opening of the fresh air valve to reduce the air conditioner according to the input of the CO 2 concentration sensor, the indoor depreciation sensor, the outdoor depreciation sensor, and based on a set C02 concentration threshold System load to achieve energy-saving energy-saving control module.

[2] The air conditioning energy-saving control system according to claim 1, wherein the system further comprises a PM

A V sensor is connected to the input of the controller.

[3] The air conditioning energy-saving control system according to claim 1, wherein the controller further comprises: adjusting the fan frequency converter according to an input of the PMV sensor and based on a set PMV threshold range Frequency and PMV control module for the cold water valve opening.

[4] An air conditioning energy saving control method based on an estimated average thermal sensation index, characterized in that: the method comprises:

Determine whether the PMV value is within the PMV threshold. If yes, do the following: In the case of cooling, set the indoor and outdoor enthalpy difference ΔΗ outdoor HH 1 - indoor H value H2; when ΔΗ<0吋, increase Daxinfeng valve opening control amount to reduce load;

When the ΔΗ>0吋, monitoring the CO 2 concentration, if the CO 2 concentration is lower than the threshold, the fresh air valve opening control amount may be appropriately reduced to reduce the load, if the CO 2 concentration exceeds the The threshold value is appropriately increased by the fresh air valve opening degree control amount.

[5] The air conditioning energy saving control method according to claim 4, wherein the method further comprises: performing the following operations in the case of heating:

When the ΔΗ>0吋, the fresh air valve opening control amount is increased to reduce the load; when the ΔΗ<0吋, the C02 concentration is monitored, if the CO 2 concentration is lower than the threshold , The fresh air valve opening degree control amount may be appropriately reduced in order to reduce the load, and if the CO 2 concentration exceeds the threshold value, the fresh air valve opening degree control amount is appropriately increased.

[6] The air conditioning energy saving control method according to claim 4, wherein the C02 concentration threshold is selectable between 700 and 1000 ppm.

[7] The air conditioning energy saving control method according to claim 6, wherein the C02 concentration threshold value is 950 ppm.

[8] The air conditioning energy-saving control method according to claim 4, wherein if it is determined that the PMV value is not within the PMV threshold, the method further comprises the following steps:

5201, PMV value set and model initialization, wherein, according to the PMV value of the PMV sensor set and the set PMV threshold range, the PMV deviation value and the PMV deviation change rate are calculated;

5202, PMV deviation value fuzzification processing, wherein the PMV deviation value is calculated according to a compiled ambiguization program;

5203, the PMV deviation change rate is blurred, wherein the PMV deviation change rate is calculated according to the prepared fuzzy program to calculate the blur amount of the PMV deviation change rate;

5204, fuzzy inference, wherein the fuzzy quantity of the PMV deviation value and the fuzzy quantity of the PMV deviation change rate are used as input parameters, and a fuzzy control rule is set in a preset fuzzy rule base to obtain a fuzzy control quantity;

5205, blur quantity clearing processing, and decomposing the fuzzy control quantity into a frequency control quantity and a cold water valve opening degree control quantity;

5206. Output processing, respectively outputting the obtained frequency control amount and the cold water valve opening degree control amount.

[9] The air conditioning energy saving control method according to claim 4, wherein the PMV threshold value is set to be between -0.5 and 0.5.