风电接入比例对电力系统暂态功角稳定性影响的分析方法

随着风电在电力系统中的占比越来越大,分析系统对风电的接纳能力日益重要。针对风电接入比例对电力系统暂态功角稳定性影响的研究尚不充分,在分析双馈风电机组对系统暂态稳定性影响途径的基础上,提出一种有利于系统暂态稳定性的最佳风电接入比例分析方法。通过风电场的等效导纳模型和节点导纳矩阵的收缩处理,依据扩展等面积定则构建了含有风电接入比例参数的系统等效转子运动方程,分析了风电接入比例对系统转子运动方程中各个参数的影响,推导得到系统功角加速度与风电接入比例的函数关系,使风电接入比例对系统暂态稳定性的影响分析得以量化。在此基础上可以确定有利于系统暂态稳定性的最佳风电接入比例,为系统中风电接入情况的合理配置提供理论指导。在MATLAB/Simulink中搭建仿真模型,对风电场不同接入比例以及不同低电压穿越方案下的系统暂态稳定性进行仿真对比分析,验证所提理论分析方法的正确性。

Analysis method of influence of wind power access proportion on transient power angle stability of power system

With the increasing proportion of wind power in power system, analyzing the wind power accep-tance capacity of power system is increasingly important. The influence of wind power access proportion on transient power angle stability of power system is not fully studied. Therefore, based on the influence approach analysis of DFIG(Doubly-Fed Induction Generator wind turbine) on system transient stability, an analysis method of optimal wind power access proportion is proposed, which is beneficial to the system transient stability. Based on the equivalent admittance model of wind farm and the shrink treatment of node admittance matrix, the equivalent rotor motion equation of the system with the parameter of wind power access proportion is constructed according to extended equal area criterion. The influences of wind power access proportion on the parameters of system rotor motion equation are analyzed, and the function relation between the system power angel acceleration and the wind power access proportion is deduced, so that the influence of wind power access proportion on system transient stability can be quantified. On this basis, the optimal wind power access proportion that is conducive to the system transient stability can be determined, providing theoretical guidance for the reasonable configuration of the system wind power access. The simulation model is built in MATLAB/Simulink, and the system transient stability under different wind power access proportions and different LVRT(Low-Voltage Ride-Through) schemes is analyzed and compared to verify the validity of the proposed theoretical analysis method.