基于基相量循环移位的基波相位和频率高精度快速检测方法

基于基相量循环移位性质,指出采样序列由DFT新算法得到的基波幅角就是信号基波初相角,从而较简捷地获得了所要检测的含谐波电参量的基波分量的初相角,提高了基波相位的跟踪能力.基于等角度间隔采样原理,提出以前述所获得的基波初相角为反馈,构成相位跟踪闭环控制,以自适应调整采样间隔,实现了对被测信号频率的自动跟踪,并达到了减少频谱泄漏,提高基波检测精度的目的.DFT新算法具有递推特性,减少了计算量,实时性较好.上述结果用于有源电力滤波器中,可以精确检测出谐波及无功电流.仿真结果表明,所提出方法的正确性和有效性.

A high accuracy and quick detection algorithm for phase and frequency of power fundamental wave based on the cyclic shift character of the base phasor

A new DFT algorithm is proposed in this paper.The fundamental wave's complex angle of the sampling data calculated by the new DFT is just the phase of signal fundamental wave.It makes the phase of fundamental wave to follow the signal rapidly.The control loop using the phase of fundamental wave as feedback is constructed to realize the adaptive sampling interval technique and make the frequency of fundamental wave to follow the signal rapidly based on the equal-angle interval technique.It greatly reduces the spectrum leakage and improves the accuracy of the fundamental wave analysis.The Step-by-Step algorithm character of the new DFT not only greatly reduces the computation burden but also ensures real time analysis.A high accuracy and quick detection method of harmonics and reactive currents in APF is proposed in this paper using the same algorithm.The simulation results show its validity and feasibility.