摘要
电力系统中发生短路故障时,使敏感负荷所在母线电压骤降到预先设定的故障范围的故障点所在区域,即为暂降域。但是在大型复杂电网中,暂降域难以准确识别。提出了一种基于临界点法的暂降域混合识别分析算法,首先给出平衡和不平衡故障下,敏感负荷点的故障残余压计算公式;在此基础上引入二次插值、黄金分割法等多种数值分析方法,将母线上的临界点求取问题简化为插值函数根的求解问题;最后采用IEEE30节点标准测试系统作为算例,验证了该方法的正确性和实用性。结果表明本方法在保证计算精度的前提下,简化了暂降域的求解过程,收敛性好,易于计算机编程实现,具有一定实用价值。
The sag domain refers to the area of the fault points at which the bus voltage of sensitive load suddenly drops to the pre-set range when a short-circuit fault occurs in the power system. However, in large complex power grids, the sag domain is difficult to accurately identify. Therefore, this paper proposes a hybrid identification analysis algorithm based on the critical-point method. Firstly, the formula for calculating the residual voltage of sensitive load points under balanced and unbalanced faults is presented. Based on this formula, several numerical analysis methods, such as the quadratic interpolation and the golden section method are introduced, simplify the problem of finding the critical point on the bus to the solution of the root of interpolation function. Finally, the IEEE standard 30-node system is used as an example to verify the correctness and practicability of the proposed method. The results show that the proposed method simplifies the solution process of the sag domain under the premise of ensuring the accuracy of the calculation. It has good convergence and is easy to be implemented by computer programming. It has certain practical value.
引文
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