Harmonic Current Detection And Control Of Active Power Filter Based On Signal Processing

With the advance of social science and technology, the wide use of power equipment and devices has brought a lot of harmonic interference to the power system. These harmonic interference has seriously affected the stability and normal operation of the power system. In order to solve the problem of harmonic pollution in power system, from the point of view of signal processing, active power filter is introduced to detect and process current harmonics. An improved ip-iq detection method based on adaptive LMS-LMF is proposed to achieve high-precision and high-efficiency harmonic current detection. And the command current tracking control is realized by combining space voltage vector and hysteresis contrast control method. The simulation results show that the response time of the improved ip-iq method is 0.05 s, the load current distortion rate is 4.31%, and the harmonic current can be detected quickly and accurately. The power factor of the system is basically kept within the range of 0.95-1, which can quickly adapt to the sudden change of load. It remains stable within 0.01 s of sudden change of load, and has good dynamic response ability. Improved ip-iq detection method based on adaptive LMS-LMF and space voltage vector. Under the comprehensive effect of hysteresis contrast control method, active power filter can effectively track the command current, suppress the harmonic current, and improve the power factor of the system. It has important practical value for improving the power quality of the power grid system.