一种基于DSP的单相谐波检测方法的研究

A Detecting Method for Harmonics in Single-phase Circuits Based on DSP

针对单相电路的瞬时谐波及无功电流检测的特点,以及常规检测方法中存在的不足,这里以瞬时无功功率理论为基础,对单相电网电流进行分解及数学分析,提出一种更适合于单相谐波及无功电流的检测方法。综合考虑实际检测中的精度和实时性问题,对所需要的主要元件低通滤波器(LPF)和锁相环(PLL)进行了详细理论分析,力求达到最好的检测结果,并利用TMS320F2812型DSP搭建实验平台,实验结果表明,该方法具有电路结构简单、计算量小、实时性好、稳定性好、可靠性高等优点。

Against the features of the detection of instantaneous harmonic and reactive current,in order to solve the shortcomings of conventional detection methods, the current in single-phase circuit is decomposed and analyzed in the way of mathematics based on instantaneous reactive power theory, then a detecting method which is more suitable for harmonics in single-phase and reactive currents based on DSP is proposed.Considering the accuracy and real-time generally in actual detection,the low-pass fiher（LPF） and phase lock loop（PLL） which is the main compo- nents in the detection is analyzed theoretically, so that the best detecting results can be obtained.A TMS320F2812 DSP-based test platform is built and the simulation results are validated.Experiments are carried out to show that this detecting method has the advantages of simple circuit, little calculation, good realtime performance, good stability and high reliability.