含风电-SMES的电力系统暂态稳定概率评估

摘要

大规模风电并网给电力系统的稳定运行带来了新的挑战，储能是应对这一挑战的技术之一。以超导磁储能(SMES)为例，提出了含风电-SMES 储能的电力系统暂态稳定概率评估方法。首先搭建了一个含有风电和储能的仿真测试平台，其中：风电场采用双馈型风力发电机等值模拟，储能的模型采用 SMES 的三阶模型。在此基础上，研究了含风电和 SMES 的电力系统暂态稳定概率评估的方法，重点考虑了故障扰动和风速波动等随机因素，故障扰动包括故障位置、故障类型、故障持续时间以及重合闸成功与否等。基于二分法和蒙特卡罗仿真，量化了系统失稳的风险，建立了风电场的渗透率、储能容量和系统稳定性之间的定量关系。最后，结合 SMES 的技术经济性分析，给出了最优储能容量计算方法。%Large scale renewable power generation brings great challenges to the power system operation and stabilization. Energy storage is one of the most important technologies to face the challenges. This paper proposes a method for transient stability probability evaluation of power system with wind farm and SMES. Firstly, a modified 11-bus test system with both wind farm and SMES has been implemented. The wind farm is represented as a doubly fed induction generator (DFIG). Then a stochastic-based approach to evaluate the probabilistic transient stability index of the power system is presented. Uncertain factors include both sequence of disturbance in power grid and stochastic generation of the wind farm. The spectrums of disturbance in the grid as the fault type, the fault location, the fault clearing time and the automatic reclosing process with their probabilities of occurrence are used to calculate the probability indices. With the proposed method based on Monte-Carlo simulation and bisection method, system stability is "measured". Quantitative relationship of penetration level, SMES coil size and system stability is established. Considering the stability versus coil size to be the production curve, together with the cost function, the coil size is optimized economically. This work is supported by National High-tech R & D Program of China (No. 2011AA05A112).