Method for detecting frosting state of heat exchanger through temperature and humidity sensors

Abstract

The invention discloses a method for detecting the frosting state of a heat exchanger through a temperature sensor and a humidity sensor, the temperature sensor and the humidity sensor are placed beside a coil pipe and in the middle of a heat exchanger fin, the temperature T and the relative humidity H of the heat exchanger fin are detected through the temperature sensor and the humidity sensor, and unit heating continuous operation time HCT is combined.The parameters are compared and analyzed with corresponding preset threshold parameters, wherein the preset thresholds include a temperature threshold T1, a temperature threshold T2, a temperature threshold T3, a humidity threshold H1, a humidity threshold H2, a heating continuous operation time threshold HCT1 and a heating continuous operation time threshold HCT2.The temperature and the relative humidity of the heat exchanger fin are obtained in real time through the temperature sensor and the humidity sensor, and state analysis and prediction are conducted on the frosting condition of the heat exchanger.According to the method, the frosting condition of the heat exchanger of a heat pump unit is accurately detected and predicted, areliable basis is provided for defrosting and frosting prevention of the heat pump unit, and the unit is prevented from entering invalid defrosting or incomplete defrosting.

Description

technical field [0001] The invention relates to an air source heat pump unit, in particular to a method for detecting the frosting state of a heat exchanger by a temperature and humidity sensor. Background technique [0002] For air source heat pumps, the weakest link in the current technology is the defrosting problem during winter operation. The frosting of the evaporator will lead to the deterioration of the performance of the air source heat pump and the decrease of the heat exchange capacity. The defrosting process increases the instability of the operation of the air source heat pump unit, resulting in a decrease in indoor comfort. The frosting of traditional heat exchangers uses the method of detecting the temperature difference between the ambient temperature and the coil temperature. However, in different environments, whether frosting depends not only on temperature, but also on humidity is an important factor for frosting. In the case of complex changes, there a...

AI Technical Summary

Problems solved by technology

Frosting of the evaporator leads to deterioration of the performance of the air source heat pump and a decrease in heat exchange capacity

The defrosting process increases the instability of the operation of the air source heat pump unit, resulting in a decrease in indoor comfort.

The frosting of traditional heat exchangers uses the method of detecting the temperature difference between the ambient temperature and the coil temperature. However, in different environments, whether frosting depends not only on temperature, but also on humidity is an important factor for frosting. In the case of complex changes, there are problems such as false detection of frosting, poor prediction effect, and complicated detection process, which lead to inaccurate results, invalid defrosting or incomplete defrosting, resulting in deterioration of unit operation performance, heating capacity, air volume, Phenomena such as COP and other performance degradation greatly affect the reliability and stability of the air source heat pump unit

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