一种DSTATCOM补偿指令电流的实时检测方法

A Detection Method for DSTATCOM Compensation Instruction Currents

提出一种改进型瞬时对称分量法。该方法根据二维时域正交坐标系中旋转相量与其瞬时值的对应关系,采用两点采样法,只需连续两次采集三相相量共计6个瞬时值即可确定各序分量的瞬时值。仿真结果表明,该方法能够实时、精确地检测出三相不对称相量中各序分量的瞬时值。基于该方法,提出一种配电网同步补偿装置(DSTATCOM)补偿指令电流的检测方法。该方法避免了复杂的移相电路、锁相环电路以及正余弦函数表的发生器及其查表过程等,消除了由此带来的误差和故障。试验结果显示,该电流检测方法能够快速、准确地检测出与系统电压基波正序分量同步的基波正序有功电流分量,从而检测出DSTATCOM装置补偿所需包含的谐波、负序以及无功分量的指令电流。

A method of improved instantaneous symmetrical components is introduced.According to the corresponding relationship of the rotating phasor and its instantaneous value in the two-dimension time domain orthogonal coordinate system,two-point sampling method is adopted,each sequence component of three-phase phasor can be confirmed by simple transforms with six instantaneous values obtained by two continuing detections.The simulative results show that,the method can detect each instantaneous sequence component from the three-phase unbalanced phasors timely and accurately.Based on this method,a detection method for DSTATCOM compensation instruction currents is presented.The method avoids the complicated phase-shift circuit,the PLL circuit and the process of looking up sine and cosine functions tables,and more importantly,the errors and faults brought by them can be eliminated.The experimental results show that the method can detect the fundamental wave positive sequence real component from the three-phase imbalanced distorted currents exactly and quickly,and correspondingly detect the harmonic,negative and reactive currents components.