Control method of electronic expansion valve of air conditioner

Abstract

The invention discloses a control method of an electronic expansion valve of an air conditioner. The control method includes the steps that after a compressor is started to run, the actual running frequency of the compressor is acquired and compared with set running frequency; if the actual running frequency is smaller than the set running frequency, the opening degree of the electronic expansion valve is controlled be to an initial opening degree; if the actual running frequency is not smaller than the set running frequency, the control process of a regulating valve is executed in the initial running stage; after the running time during which the compressor is started to run is equal to set initial running time, the control process of the PID regulating valve is executed; and with the difference value between the actual exhaust temperature and the target exhaust temperature of the compressor as deviation, the PID control process is performed on the opening degree of the electronic expansion valve based on the deviation. By means of the control method, the opening degree of the electronic expansion valve can be dynamically, fast and accurately regulated, and the energy efficiency ratio of an air conditioner refrigerant circulating system is increased.

Description

technical field [0001] The invention belongs to the technical field of air conditioning, and in particular relates to a control method for an air conditioner, and more specifically relates to a control method for an electronic expansion valve of an air conditioner. Background technique [0002] As a new type of control element, the electronic expansion valve is widely used in the air-conditioning refrigerant circulation system. By adjusting the opening of the electronic expansion valve, the refrigerant circulation volume in the system can be adjusted to meet the operating performance requirements of the air conditioner. Therefore, how to effectively control the electronic expansion valve is the key to measure the energy efficiency ratio of the air conditioning system. [0003] In the prior art, the opening degree of the electronic expansion valve of the air conditioner is usually adjusted by means of checking the superheat degree table and adjusting the valve method by looki...

AI Technical Summary

Problems solved by technology

One of its disadvantages is that there is not much difference between the suction temperature and the coil temperature, the difference is small, the accuracy of the superheat is not enough, and the problem of overshoot is prone to occur

In addition, because the air conditioner adopts capillary flow distribution, there are many distribution channels, generally 5-6 distribution channels, and it is difficult to ensure good distribution consistency in production and assembly, so the coil temperature during operation is also It is difficult to ensure good consistency, and the temperature deviation of the coil is large, resulting in low accuracy of the superheat table and valve adjustment

Although the exhaust temperature look-up meter control valve has more advantages than the superheat control valve, its control accuracy is low, which belongs to coarse control, and it is also very prone to over-regulation problems at low frequencies

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