基于场路结合法的500 kV线路绝缘子串分布电压的计算

Calculation of the Voltage Distribution of Insulator Strings in 500 kV Lines Based on the Combination of Electrical Field and Road

高压线路绝缘子串的电压分布极不均匀并且测量难度较大。为此,提出了一种新的计算绝缘子串分布电压的方法,该方法通过Maxwell电容矩阵计算出绝缘子杂散电容,再将其代入到绝缘子串等效电路中进行计算,比传统有限元方法考虑更全面,且更加简便。通过该方法对某500 kV线路绝缘子串电压分布进行了仿真计算,通过试验验证其结果与实测一致,且比传统电路法更精确。利用此算法初步计算了500 kV线路不同位置绝缘子发生劣化对绝缘子串电压的影响,指出了目前劣化绝缘子的判定方法可能会造成漏判。

The voltage distribution of high-voltage line insulator strings is extremely uneven and difficult to measure.This paper presents a new method for calculating the voltage distribution of insulator strings. This method calculates the insulator stray capacitance by Maxwell capacitance matrix and then substitutes it into the equivalent circuit of the insulator string for calculation. It is more comprehensive and more accurate than traditional methods. Through this method,the voltage distribution of insulator strings in a 500 kV line is simulated and the result is in good agreement with the actual measurement through experiment and it is more accurate than traditional circuit method. It is proved that the algorithm is feasible. Use this algorithm to calculate the influence of insulator deterioration at different positions of 500 kV line on the voltage of insulator strings. It is pointed out that the current method of deteriorating insulators may cause missed judgments.