MOA谐波阻性电流补偿算法的研究

Study on the Harmonic Resistive Current Compensation Algorithm of MOA

金属氧化物避雷器(MOA)泄漏电流阻性分量中基波分量iR1及3次谐波分量iR3能够准确反应MOA运行状态,考虑谐波干扰时,由于谐波电压幅值及相位的不确定性,直接测量总阻性电流存在较大误判可能,针对电容法存在的不足,提出了改进补偿算法,利用谐波阻性电流幅值相位关系进行电流补偿,得到较为准确的基波电压作用下阻性电流。MATLAB仿真实验表明,通过改进算法计算iR3误差大大降低,验证了文中算法的有效性,提高了MOA运行判别的准确性。

The fundanaental component iR1 and the third harmonic component ipa of metal oxide arrester （MOA） leakage current resistive component can reflect the operation state of MOA. Due to the uncertainty of harmonic voltage amplitude and phase,there may be a big misjudgment in measuring total resistive current directly when considering the influence of frequency fluctuation. In the light of inadequacy of the capacitance method,an improved compensation algorithm is proposed in this paper,which can compensate current by use of the relationship between harmonic resistive current amplitude and phase, so that more accurate resistive current under the action of fundamental voltage can be obtained. The results simulated by MATLAB show that the error of iR3 computed by the improved algorithm can be greatly reduced, and also verify the effectiveness of this algorithm, so the accuracy of judging MOA operation can be further improved.