提高暂态电压安全水平的动态无功备用优化方法

Abstract

电力系统动态无功储备对提高系统暂态电压安全水平具有重要作用,因此提出一种在系统暂态过程中考虑暂态电压安全的无功备用概念,并给出其对暂态电压安全贡献的评价方法及相应的修正系数。通过轨迹灵敏度方法实现对修正后的无功源动态无功备用的计算,建立提高系统暂态电压安全水平的无功备用优化模型,利用原对偶内点法进行求解。IEEE 39节点算例结果表明,所提3种权重系数合理、有效,通过该评价方式可以充分考虑到无功备用点对点的支撑能力以及故障严重性对无功备用的要求程度,通过系统动态无功备用的优化可提高系统的整体暂态电压安全水平,因此所提方法能够有效地预防系统故障时暂态电压安全问题的发生。

Dynamic reactive power reserve of power system is vital to improve transient voltage security. An novel definition of reactive power reserve considering transient voltage security in transient procession was proposed. Correction coefficient to evaluate reactive power reserve's contribution to transient voltage security was given. Corrected reactive power reserve was computed through trace sensitivity method. Then an optimization model to enhance transient voltage security was built. It was solved by primal dual interior point method. Testing on IEEE 39-node system, it is indicated that three weight coefficients proposed are reasonable and effective. The evaluation method can give consideration both supporting capacity of one bus to the other and demand of reactive power reserve according to severity of faults. The system's transient voltage security is enhanced by the way of optimization of system's dynamic reactive power reserve. Hence, the method proposed can be used to prevent the happening of transient voltage collapse during system's fault.