冷库工程变频压缩机组的谐波治理

Harmonic Control of Variable Frequency Compressor Units in Cold Storage Engineering

针对冷库工程大功率变频压缩机应用越来越普遍、低压配电系统的谐波危害越来越严重的问题,在无功功率补偿柜电容器前端串接电抗+有源滤波器可以很好地治理谐波。通过对变频器工作原理的分析,结合实际工程案例计算各次谐波含量,可以准确选择串联的电抗率和需要配置的有源滤波器容量,提出:从保护电容器、保证无功补偿装置安全运行的角度考虑,串联电抗率7%更适合冷库工程的使用。

With the increasing application of high-power variable frequency compressors incold storage engineering,the problem of harmonics in low-voltage distribution systems becomes increasingly severe,the use of active filters in conjunction with reactorsc connected in series at the front end of capacitor banks for reactive power compensation cabinets can effectively control harmonics.By analyzing the working principle of the frequency converter and considering practical engineering case,the harmonic content of each order can be calculated.This allows for the accurate selection of the series reactance ratio and the required capacity of the active filter.It is proposed that,from the perspective of protecting capacitors and ensuring the safe operation of reactive power compensation devices,a series reactance ratio of 7%is more suitable for cold storage engineering.