波动量法中临界电流数据筛选策略的可行性研究

在利用波动量法估计谐波发射水平中,发现波动量法建立在大量数据采集基础之上,因此,采用该方法进行系统谐波阻抗估计时,易受到不良数据的影响而导致估计精度低下。临界电流数据筛选策略通过电压、电流波动量之间的关系曲线,求得临界电流值,再以临界电流作为筛选数据的标准。通过PSCAD仿真软件,构造了仿真模型,进行蒙特卡罗仿真,再利用MATLAB软件进行曲线拟合,研究临界电流数据筛选策略是否可以有效地提高谐波阻抗估计值的精度,从而准确地估计出用户侧谐波发射水平。

Feasibility research on the selection strategy of critical current data in the fluctuation method

When using fluctuation method to estimate the amount of harmonic emission levels,the large number of measured data is the basis.So this method is vulnerable to bad data which may decrease the estimation accuracy when the system-side harmonic impedance is estimated.The critical current data selection strategy calculates the critical current by the curve of the voltage fluctuations versus the current fluctuations.The critical current can be used as a data selection standard.A simulation model is proposed,and PSCAD based Monte Carlo simulation and Curve fitting through MATLAB are performed.The simulation studies whether the critical current data selection strategy can effectively improve the accuracy of harmonic impedance estimation,then precisely estimate the load-side harmonic emission level.