计及直流控制方式转换和换流变变比调整的交直流潮流算法研究

在分析统一迭代法及交替迭代法优缺点的基础上，提出了改进的交替迭代法以计算交直流系统潮流。该算法计及了直流变量的边界约束，对交流及直流系统潮流方程均采用牛顿拉夫逊法求解，确保了直流子系统雅可比矩阵可逆。分析了交流系统修正雅可比矩阵在计算过程中可能出现虚部的原因，给出了换流变分接头调整的策略。以修改后的IEEE39系统为例，验证了所提算法的正确性。重点讨论了当节点负荷缓慢增加时，潮流计算中换流变调整分接头，无功补偿设备的投切和直流控制方式发生改变的详细过程及以上因素对电压稳定极限的影响。

Study on AC/DC power flow algorithm considering the switching of DC control mode and converter transformer ratio

Based on analyzing the merits and drawbacks of the uniform and alternating iteration method,an advanced AC/DC power flow algorithm is presented,which considers the boundary constraint of the DC variables.The power flow equations of the AC and DC system are all solved by Newton-Laphson method.It makes the Jacobi matrix of DC system reversible.This paper analyzes the reason why the element of correctional Jacobi matrix of AC system emerges imaginary part during the course of calculation,and gives the way to a...