电网谐波和无功有源补偿技术的研究与应用

The study and application of active compensation techniques for harmonics and reactive power in power systems

针对目前电力系统谐波抑制和无功补偿的特点和现状,提出了将晶闸管投切无源滤波器TSF和有源电力滤波器APF串联混合使用,且LC滤波器中电容量完全按无功补偿需要选取,而不另装普通的无功并联电容器的综合补偿方案,使谐波抑制和无功补偿融为一体,保证了电容器的安全运行.并采用检测负载电流和电网谐波电流的复合控制方法,既可有效抑制电网谐波电流,又可防止无源器件与电网间发生的谐振,达到理想的综合控制效果.文章着重介绍了混合系统的工作原理和控制方法,进行了实验系统设计和实验研究.理论分析和实验均表明,所选方案和控制方法是正确的、可行的,对电网谐波污染和无功损耗均有很好的抑制和补偿作用.

In view of the characteristic and the current situation of the technology on harmonic restraining and VAR offsetting, the paper puts forward the use of series connection between thyristor switched filter and active powered filter, as well as the comprehensive schemes to determine the capacity of condenser in LC filter according to the needs of VAR offsetting, without any other common reactive parallel connected condenser. Thus, the harmonic restraining can be mixed together with the VAR offsetting, which ensures the safe working of the condenser. A good result to control can be reached by using mixed controlling way of testing load current and harmonic current, not only can it restrain effectively the harmonic current, but it also can avoid resonance between the passive parts and the power net. The paper focuses on the working principle and the controlling way of the mixed system, and it also gives designing and research on experiments. Both analyses and experiments in this paper can prove that the schemes and ways above are correct and feasible, that they are useful to restrain the harmonic pollution and to offset the VAR consumption.