一种计算3/2接线方式下开关设备回路电阻的新方法

A New Method for Calculation of Switchgear Circuit Resistance in 3/2 Wiring Connection Mode

针对3/2接线方式变电站开关设备回路电阻的在线计算问题,提出一种基于电流和有功功率测量的在线评估方法。利用基尔霍夫定律和焦耳定律建立开关设备回路电阻的数学模型,将计算开关设备回路电阻的问题转化为线性最优规划问题。在求解最优规划问题的过程中,采用遗传算法可大大减少求解规划问题的难度,避免最终结果陷入局部最优解。以采用3/2接线方式的某500 k V变电站的实测电流和有功功率数据进行仿真计算,验证该方法的有效性。

Aiming at the problem of online calculation of circuit resistance for substation switchgear which uses the 3/2 connection mode, the online evaluation method based on the measurement of the current and active power is proposed. Kirchhoff＇s and Joule＇s laws are used to establish the mathematical model of switching equipment＇s circuit resistance, therefore, the problem of calculating the circuit resistance of the switching equipment is transformed into an optimal linear programming problem. During the process of solving the optimal programming problem, difficulties encountered are greatly reduced by using the genetic algorithm. Therefore, the final result avoids falling into local optimal solution. Simulation studies on the current and active power data obtained from the 500 k V substation which uses the 3/2 connection mode verify the effectiveness of the proposed method.