Over-temperature protection method of variable frequency drive for air conditioner and its variable frequency drive

Abstract

An over-temperature protection method for a variable frequency drive for an air conditioner, comprising: acquiring temperature information of a radiator module and a power module of the variable frequency drive; when Temp1≤T1<Temp2, controlling the frequency conversion drive to increase the frequency slowly, and when Temp2≤T1<Temp3 When Temp3≤T1<Temp4, control the frequency conversion drive to reduce the frequency slowly, when T2≥Temp4, control the frequency conversion drive to rapidly reduce the frequency; among them, T1 is the temperature of the radiator module, T2 is The temperature of the power module. Temp1 is the temperature threshold for slow frequency upscaling, Temp2 is the temperature threshold for prohibiting upscaling, Temp3 is the temperature threshold for slow downscaling, and Temp4 is the temperature threshold for fast downscaling. The invention also provides a variable frequency driver. The invention can timely respond to the over-temperature state of the variable frequency drive and make corresponding protection, and has high reliability.

Description

technical field [0001] The invention relates to the frequency conversion air conditioner technology, in particular to the overtemperature protection technology of the frequency conversion driver for the air conditioner. Background technique [0002] With the gradual elimination of fixed-frequency machines, variable-frequency drives are more and more widely used in air conditioners. In order to avoid overheating damage, the existing variable frequency drives for air conditioners usually have an over-temperature frequency reduction protection function. The control module of the variable frequency drive compares the temperature of the radiator module of the variable frequency drive detected by the temperature sensor with the preset temperature threshold. Throttle down when the temperature threshold is exceeded. This solution mainly has the following disadvantages: 1. The temperature change of the radiator module is slow. Compared with the power module of the variable frequency...

AI Technical Summary

Problems solved by technology

This solution mainly has the following disadvantages: 1. The temperature change of the radiator module is slow. Compared with the power module of the variable frequency drive, the temperature change is obviously lagging behind, which leads to the inability to respond to the overtemperature state of the variable frequency drive in time, thereby affecting the overtemperature protection effect; 2. , the reliability needs to be improved

Once the temperature sensor fails, it will not be able to achieve overheating protection

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