基于改进Chord法的电力系统连续潮流计算新方法

连续潮流计算是电力系统研究静态电压稳定和传输能力应用的重要工具,但临界点处的奇异性制约了连续潮流计算的应用和发展。因此,解决好临界点病态问题是更好应用连续潮流的关键。应用改进Chord法处理连续潮流问题中临界点处的计算,能够快速计算该点处的解,收敛速度快,达到二阶收敛。不用扩展原雅可比矩阵,因此不需要担心原系统中的非奇异点变为系统扩展雅可比矩阵的奇异点问题,使计算过程更为简单。应用线性化方法预测连续潮流计算方向,整个计算过程简洁方便。在计算及分析中与扩展潮流计算方法进行比较,体现了所提Chord法简洁、高效的优点。不同工况下,IEEE39和IEEE57节点系统仿真算例结果表明,所提模型和方法能够快速有效地计算连续潮流和临界点处的奇异解,有着很好的精确性和鲁棒性。

A new method of power system continuous flow calculation based on an improved Chord method

Continuous power flow(CPF)calculation is an important tool for power system analysis in studying static voltage stability and system transmission capacity.However,a critical point singularity seriously restricts the application and development of CPF.Therefore,the key to better application of CPF is to solve the problem of the critical point singularity.An improved Chord method is proposed to deal with the calculation of the critical point in the CPF problem.It can quickly calculate the solution at the critical point,and has fast convergence speed,reaching second-order convergence.It does not need to expand the original Jacobian matrix,so it does not need to worry about the problem that the nonsingular points in the original system become the singular points of the extended Jacobian matrix of the system.This makes the calculation process simpler.Applying the linearization method to predict the calculation direction of CPF,the whole calculation process is simple and convenient.Compared with the extended power flow method,the Chord method presented in this paper is simple and efficient.The simulation results of the IEEE 39-bus and IEEE 57-bus systems under different working conditions show that the proposed model and method can quickly and effectively calculate the singular solutions of CPF,and it has a good accuracy and robustness.