Air conditioning system and its expansion valve control method and control device

Abstract

The invention discloses an air conditioner system and a control method and device for an expansion valve of the air conditioner system. The method includes the steps that the exhaust temperature and the exhaust pressure of the air conditioner system are obtained; the exhaust superheat degree is obtained according to the saturated temperature corresponding to the exhaust temperature and the exhaust pressure; whether the exhaust superheat degree is smaller than the preset superheat threshold value or not is judged; if the exhaust superheat degree is smaller than the preset superheat threshold value, whether the exhaust pressure is larger than the preset pressure threshold value or not is further judged; and if the exhaust pressure is larger than the preset pressure threshold value, the first adjusting coefficient is obtained according to the exhaust superheat degree, the second adjusting coefficient is obtained according to the exhaust pressure, the opening degree of the expansion valve is adjusted according to the first adjusting coefficient and the second adjusting coefficient, and therefore the opening degree of the expansion valve is adjusted through the exhaust superheat degree and the exhaust pressure together, the exhaust superheat degree can be stabilized in a normal range, it is ensured that a compressor of the air conditioner system runs reliably, meanwhile, excessively high exhaust pressure caused by excessive adjustment of the expansion valve can be avoided, and reliability of the air conditioner system is improved.

Description

technical field The invention relates to the technical field of air conditioners, in particular to an expansion valve control method for an air conditioning system, an expansion valve control device for an air conditioning system, and an air conditioning system. Background technique In related technologies, the air conditioning system usually controls the exhaust superheat by controlling the opening of the expansion valve of the external unit. For example, when the exhaust superheat is low, the expansion valve opening is reduced to increase the exhaust superheat. However, the disadvantage of the related technology is that when the exhaust temperature is high and the exhaust pressure is high, the exhaust superheat may be low due to the increase of the saturation temperature corresponding to the exhaust pressure. At this time, if the exhaust superheat Reducing the opening of the expansion valve will further increase the exhaust temperature and pressure, which will deteriorate ...

AI Technical Summary

Problems solved by technology

However, the disadvantage of the related technology is that when the exhaust temperature is high and the exhaust pressure is high, the exhaust superheat may be low due to the increase of the saturation temperature corresponding to the exhaust pressure. At this time, if according to the exhaust superheat Reducing the opening of the expansion valve will further increase the exhaust temperature and exhaust pressure, which will deteriorate the operating conditions of the air conditioning system and affect the reliability of the air conditioning system

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