具有不平衡负载的功率因数补偿策略的研究

将单相谐波和无功电流检测方法应用于三相系统中。在每相中分别采用与电网电压同频同相的单位正弦和余弦信号与该相负载电流相乘，经过低通滤波和处理后得到各相的瞬时基波有功电流和瞬时基波无功电流，进一步可得到谐波指令电流，和补偿谐波、无功及不平衡电流的指令电流，通过该电力滤波器补偿后，解决了三相不平衡问题，得到高的功率因数。通过仿真研究，证明了该方法的正确一性。

The Research of a Novel Power Factor Compensation Method with Unbalanced Three Phase Loads

The detecting method of harmonics and reactive currents in single-phase is applied in three-phase four-wire system in this paper. Firstly, the single-phase current is multiplied respectively by sinusoidal and cosinoidal signals with the same frequency and same phase of that circuit voltage, and then pass by two low pass filters to get the instantaneous fundamental active and reactive currents. Then harmonics reference currents can be obtained. Reference currents for compensating harmonics, reactive and unbalanced currents can be obtained by subtracting balanced fundamental active currents from original load currents. This paper solves problems with low power factor and unbalanced three phase loads. The simulation results show the validity of this detecting method.