Variable frequency air conditioning system and control method thereof

Abstract

The invention relates to a variable frequency air conditioning system and a control method thereof. The variable frequency air conditioning system comprises a fixed frequency compressor, a variable frequency compressor, an evaporator, a first condenser and a second condenser, wherein the evaporator comprises a fixed frequency evaporation unit, a variable frequency evaporation unit and a hierarchical control and regulation valve connected with the variable frequency evaporation unit. The fixed frequency compressor, the first condenser and the fixed frequency evaporation unit are connected sequentially to form an fixed frequency air conditioning circuit; the variable frequency compressor, the second condenser, the variable frequency evaporation unit and the hierarchical control and regulation valve are connected sequentially to form an variable frequency air conditioning circuit; and the evaporator is provided with a fan, and the hierarchical control and regulation valve is electrically connected with the fan and the variable frequency compressor to coordinate and hierarchically control the output of the fan and the variable frequency compressor. Stepless energy regulation is achieved by switching the fixed frequency and variable frequency dual system, the hierarchical control over the fan and the variable frequency evaporation unit is achieved through the hierarchical control and regulation valve, the suction pressure regulation range of the variable frequency compressor is improved, the suction pressure is made reasonable, and the operation reliability of the variable frequency compressor is ensured.

Description

technical field [0001] The present invention relates to the technical field of frequency conversion air conditioning system, and more specifically, relates to a frequency conversion air conditioning system and a control method thereof. Background technique [0002] At present, many frequency conversion air conditioners for computer room air conditioners are concentrated in small cooling capacity and single frequency conversion compressor systems. The compressor and fan are adjusted according to the energy mode of frequency conversion matching output. The adjustment is relatively simple, and the system operation is relatively reliable. [0003] However, for frequency conversion systems with large cooling capacity, there are relatively few applications, and the control is relatively complicated. The main problems are as follows: [0004] 1. There are oil and gas equalization problems in the parallel connection of dual compressors for large cooling capacity, especially in the p...

AI Technical Summary

Problems solved by technology

[0003] However, for frequency conversion systems with large cooling capacity, there are relatively few applications, and the control is more complicated. The main problems are as follows:

[0004] 1. There are oil and gas equalization problems in the parallel connection of dual compressors for large cooling capacity, especially in the parallel connection system of low-voltage inverter air conditioners, it is difficult to guarantee the reliability of the compressor operation, and the failure rate of the compressor is relatively high;

[0005] 2. For the frequency conversion system composed of single fan and double compressor (fixed frequency compressor + variable frequency compressor), it is difficult to solve the problem of reliable operation control consistency of the fan and compressor

Images