一种改进的瞬时功率算法研究

针对目前电网谐波背景下不同次谐波功率会正负抵消的不合理现象,提出一种改进的瞬时功率理论计算方法。该方法首先将单相电压、电流信号延时构造出三相电压、电流信号,然后通过改变瞬时无功功率理论中p-q坐标系的旋转速度,滤波后得到电压电流中不同频次谐波的信号,最后通过功率转换求得系统的有功功率和无功功率。该方法不仅可以分别对功率进行正反向分别计量,避免电能计量时正反向功率抵消的不合理现象,而且在单相系统和三相系统中均可使用。通过Matlab进行仿真,验证了本文方法的有效性和准确性。

Research on an Improved Instantaneous Power Harmonic Detection Algorithm

Aiming at the unreasonable phenomenon that the different harmonic power will be cancelled out in the current harmonic background,an improved instantaneous power method is proposed to improve in this paper.First,the three-phase voltage and current signals are constructed by the delay of single-phase voltage and current signals.Then by changing the rotational speed of the pq coordinate system in the instantaneous reactive power theory,the signals of different frequency harmonics in the voltage and current are obtained after filtering.Finally,the active power and reactive power of the system are obtained by the power conversion.This method can not only measure the power in positive and backward separately,but also avoid the unreasonable phenomenon of the positive and reverse power offset when the electric energy is measured,and can be used in the single phase system and the three-phase system.The simulation results of Matlab verify the effectiveness and accuracy of the proposed method.