运用特征值法确定交直流系统电压失稳区

直流输电可以对其功率快速地进行调节,从而提高与直流系统相连接的交流系统的稳定性,所以交直流系统在国内外应用得越来越多,而研究如何定量地分析交直流系统的电压稳定性成为了当前比较迫切需要解决的问题。该文结合交直流系统的特点,采用改进的牛顿法求解交直流系统的潮流,在得到收敛潮流的最小特征值及其左右特征向量后,计算出各节点的参与因子,并以参与因子为依据,采用特征值法对在一定直流控制方式下的交直流系统进行电压稳定性分析,找出交直流系统的电压易失稳区,从而为采取相关措施提高整个交直流系统的电压稳定性提供有价值的参考依据。最后通过对一个9节点的交直流系统采用本文方法进行仿真计算,证明了本文所述方法的有效性和可行性。

Voltage weak stability zone calculation of AC/DC system using eigenvalue method

HVDC system can adjust its direct power flow quickly to enhance the voltage stability of the AC system which is connected with the DC system.It is very urgent to find a method to analyze the voltage stability of the AC/DC systems.Based on the characteristic of the AC/DC system,a modified Newton-Raphson load flow method is proposed to calculate the AC/DC system power flow.After the calculation,the smallest eigenvalue and its eigenvectors can be obtained.Then every bus's participation factors can be calculated by using them.Based on the participation factors,the voltage stability of the AC/DC systems which operates under a certain DC control mode can be analyzed using the eigenvalue method and the voltage weak stability zone of the AC/DC systems can be obtained.The feasibility and effectiveness of this method is verified by the simulation of a AC/DC system using Powerworld and Matlab.