两种电铁谐波及无功电流检测方法的研究与仿真

Analysis and Simulation of Detecting Approaches of Instantaneous Harmonic and Reactive Current in Electrical Railway

针对电气化铁道供电系统对谐波及无功电流检测的要求,介绍了两种检测方法,并分别给出了检测原理图。前者是基于鉴相原理的瞬时谐波电流检测法,后者是基于瞬时无功功率理论的谐波分离法,对该方法基于不同截止频率时的LPF进行了分析比较。理论分析和仿真结果证明两种方法都能实时地检测出电铁供电系统中的瞬时谐波及无功电流,前者算法和实现更为简单。稳态运行的仿真波形证实了文中所提方法的有效性。

This paper presents two detecting methods of harmonic and reactive current in order to meet the demand of electrical railway feeding system, and gives principle diagram of detecting circuit respectively. The former is an instantaneous harmonic current detecting method based on the phase distinguishing technology, the latter is harmonic current separate method based on instantaneous reactive power theory, which is analyzed and compared in different cut- off frequency of LPF. Theory analysis and simulation results verify that instantaneous harmonic and reactive currents in electrical railway feeding system can be detected in real time with two methods mentioned before, and the former is simpler in algorithm and implement. Simulation waveforms for steady state show the effectiveness of the proposed methods.