采用可控并联补偿长输电线路的电压控制

对于并补高压远距离输电线路的电压控制,设定边界条件、简化线路等值参数、静止无功补偿器(SVC)斜率、系统静态电压特性等,将导致较大计算误差.本文采用线路分布参数的准确等值模型,建立给定边界条件下长线路电压分布的直接解析算法,量化简化等值参数模型的计算误差.采用并联支路电纳为控制变量,建立包括SVC斜率和系统静态电压特性的SVC电压控制模型,计算不同电压扰动下的SVC电纳增量,以及并补控制后的节点电压和长线路潮流.

Voltage Control to Long Transmission Lines by Controllable Shunt Compensation

Fixed boundary conditions,simplification to the equivalent line parameters,slope of static var compensator (SVC),and static voltage characteristics of the system,will introduce remarkable error to the voltage control of long shunt-compensated transmission lines. In this paper exact equivalent line model with distributed parameters is adopted for direct analytical solution to voltage distribution of long lines with fixed boundary conditions,which prove the calculation error caused by the simplified equivalent parameters. By taking the shunt susceptance in the shunt compensated path as controlled variable,voltage control model including the slope of SVC and the static voltage characteristics of the system is presented to find the necessary susceptance change for SVC for different voltage disturbances,bus voltages,and power flow on the long transmission lines.