基于瞬时无功功率理论的电压波动检测和闪变计算

摘要

将电压波动看成以工频电压为载波,其电压的方均根或峰值受到以电压波动分量作为调幅波的调制.在三相电路瞬时无功功率理论的基础上,由单相电压波动信号构造对称三相电压,并推导了由电压波动信号求得调幅波的过程.主要运用瞬时无功功率检测法进行电压波动检测的仿真和短时闪变值的计算,并与IEC推荐的平方检测法进行比较.仿真结果表明基于瞬时无功功率理论的电压波动检测法计算得到的短时闪变值更接近真实值,相对误差更小,从而验证了该方法的有效性.%In this paper, voltage flicker is regarded as a signal generated by power-frequency voltage and the root-mean-square or the peak value of the voltage is modulated by amplitude-modulated wave which is the voltage fluctuation component. We construct a symmetrical three-phase voltage through voltage fluctuation signal of single phase based on instantaneous reactive power theory in three-phase circuits and derive the computation process of modulated wave. Instantaneous reactive power theory detection method is used for simulation of voltage fluctuations and calculation of short-time flicker value and compared with square detection recommended by IEC. The result of simulation shows that the flicker values obtained by instantaneous reactive power theory detection are close to the real value and relative error is smaller, and thus verifies the effectiveness of this method.