大规模交直流电力系统电磁暂态仿真高效建模方法

A High Efficiency Modeling Method for Electromagnetic Transient Simulation of Large Scale AC/DC Power System

为克服机电暂态仿真无法描述交直流混合电力系统非基波或不对称特性的局限性,急需高效的大规模电力系统电磁暂态建模方法。针对实际高压直流输电换流站主接线方式,文章首先简化了阀组模型并说明了对应简化模型的输电线路模型,大大减少了模拟换流站而利用的计算资源;其后介绍了适用于基于文本转换的电磁暂态快速建模技术的模型定义方法,该模型充分利用了矩阵计算,易于初始化且提高了计算速度。以一个两区四机系统验证了采用所提简化直流模型的精确性与自定义模型的有效性,以南方电网主网等值系统为例说明了大电网电磁暂态建模的步骤,并提出了提高机电暂态仿真精度的建议。

In order to overcome limitation of electromechanical transient simulation which is unable to describe non-fundamental frequency or asymmetry characteristic of hybrid electric power system, modeling method with high efficiency is urgent for large scale power system electromagnetic transient simulation. Firstly, according to an actual HVDC converter station, this paper simplifies valve group model and illustrates corresponding transmission line model to reduce computing resource demand for converter stations. Secondly, a modeling method suitable for text conversion based fast modeling technology is presented. The model makes full use of matrix calculation, helping to initialize and improve calculation speed. Finally, simulations of a modified system of 2-area 4-machine grid show effectiveness and accuracy of the DC model and user-defined models. Electromagnetic transient modeling procedure is demonstrated with Southern China Power Grid equivalent system. Suggestions are put forward to improve accuracy of electromechanical transient simulation.