初值优化的电力系统戴维南等值跟踪算法研究

在电力系统分析计算时,需要对电网进行等值处理。戴维南等值是常用的等值手段,它能够反应系统运行状况并且具有模型清晰、简单快速的特点。针对现有方法求取戴维南等值参数时,存在参数漂移和参数跟踪问题,提出基于初值优化的偏差校正跟踪算法,利用相邻运行点的戴维南等值电压幅值不变、相角变化,进而获取等值跟踪初值,采用偏差校正方式进行跟踪电网运行点的变化。初值优化算法与偏差校正方法相结合能够快速跟踪等值参数,又能够避免参数数值计算不稳定。通过跟踪性能测试和四机两区域系统仿真算例,证明了所提算法的可靠性、准确性与有效性,能够快速跟踪实际电网运行方式。

An Initial Value Optimization Algorithm to Track Thevenin Equivalent Parameter

As interconnected power systems expand, the Thevenin equivalent is widely used in power system, which can reflect the operating conditions of system because of its clear, simple and rapid characteristics. Based on the parameter drift and tracking problems in obtaining the Thevenin equivalent parameter with existing method, an improved deviation correction algorithm is proposed in this paper to track the Thevenin equivalent parameter. The algorithm computes the initial value of parameter in case of constant Thevenin equivalent voltage amplitude and varied phase angle of the adjacent operating point. The deviation correcting mode is used to track the changing operation point of power gird. The combination of initial value optimization algorithm and deviation correction method can not only rapidly track equivalent parameters, but also avoid the numerical instability. At last, the tracking performance testing and four-machine two-area system simulation have proved the accuracy and applicability of the proposed algorithm for actual grid operation mode.