针对大功率非线性负载的有源滤波器
来源期刊：中南大学学报(自然科学版)2002年第2期
论文作者：赵巍 涂春鸣 罗安 杨建
文章页码：201 - 204
关键词：非线性负载;有源滤波器;单次谐波;检测
Key words：nonlinear load; active filter; single harmonic; detection
摘 要：采用现有有源滤波器对大功率非线性负载进行谐波滤除时,要求逆变器同时具有很大的容量和较高的开关频率,这必然增加逆变器的技术难度和成本,限制了有源滤波器在大功率场合的应用.作者针对这一问题提出一种新型并联混合型有源滤波器,根据非线性负载产生的主要谐波分量设计逆变器以减小逆变器电流容量,同时逆变器输出电压频率较低,逆变器开关频率可相应降低.逆变器与无源滤波器电感并联,当逆变器发生故障时,无源滤波器仍能正常工作.由于并联滤波电感的分流作用,逆变器电流减小.此外,还提出一种以ip-iq法为基础的单次谐波电流检测方法.Matlab仿真结果表明,并联混合型有源滤波器滤波效果与现有并联混合型有源滤波器的滤波效果接近,但其中逆变器电流减少50%.
Abstract: For high-power nonlinear loads, the existing active filter topologies are not effective due to their large rating and high-switching-frequency requirement of inverter. In order to solve the problem, the authors propose a novel hybrid parallel active filter (HPAF) for high-power nonlinear loads. Individual small-rated inverters are designed for dominant harmonics. The bandwidth requirement of the inverter is reduced so the inverter can work at lower switching-frequency. Inverters are connected in parallel with the passive filter inductors. The passive filter can operate by itself if the inverter is in the high-impedance mode. Because the significant portion of fundamental and harmonic components flows through the passive filter inductor, the current loading to the inverter is reduced greatly. A single-harmonic detection method based on ip-iq theory is also proposed. Judging from the computer simulation by Matlab, the proposed HPAF has the same filter characteristics as the existing HPAF, butthe inverter current of the proposed HPAF is about 50% of the inverter current of the existing HPAF.
