基于有源滤波器的同相供电系统补偿电流的实时检测

基于有源滤波器的同相供电系统的关键技术是对补偿电流的实时检测,检测的精度高低和动态响应性能好坏会影响三相平衡效果和谐波与无功的补偿效果。本文针对以往检测方法存在动态响应速度慢的缺点,提出了2种补偿电流检测方法:有功电流分离检测法和无延时虚拟三相检测法。分析与仿真证实,无论被检测电压与电流有无畸变,2种检测方法都可根据同相供电平衡补偿的不同要求(仅平衡三相、平衡三相滤除谐波和平衡三相滤除谐波并补偿无功)完成补偿电流检测,且检测精度高、动态响应速度快。

Real-time Detecting of Compensating Currents of the Cophase Supply System with Active Filters

The key technique of the cophase supply system with active filters is real-time detecting of compensating currents.The degree of the detecting precision and the quality of dynamic responses affect the effects of three-phase balance and harmonics and reactive current compensation.Aiming at overcoming the disadvantages of low speeds of dynamic responses of existing detecting methods,this paper proposes two methods for detecting compensating currents,namely the method of separating active currents and the method of virtual three-phase without time delay.Verified from analysis and simulations in this paper,no matter whether the detected voltage or current has any distortion or not,these two detecting methods can both accomplish detecting of compensating currents with high precision and quick dynamic responses according to different requirements(balancing three-phase,balancing three-phase and filtering harmonics,balancing three-phase and filtering harmonics and compensating reactive currents) for balance compensations of cophase supply.