利用广义诺顿定理调整输电线路参数不对称性的方法

Method of adjusting parameter asymmetry for transmission line using generalized Norton theorem

为了降低高压输电线路上的不对称电压,维持电网的稳定运行,提出基于三相高压输电线路的诺顿等值电路.将不对称的线路参数看作诺顿等值电路的等效导纳,通过调节末端变电站中静止无功补偿设备的投切量,使其端口电压接近三相对称,从而达到降低线路上不对称电压的目的.理论计算结果及Matlab仿真分析表明,该方法可以使得线路末端电压的不平衡度降到最低,从而改善整条线路的不对称状况.

In order to reduce asymmetric voltage on high voltage transmission line and maintain stable operation of power grid,a Norton equivalent circuit based on the three-phase high voltage transmission line was proposed.The asymmetric line parameters were treated as the equivalent admittance of Norton equivalent circuit.Through adjusting the switched amount of static reactive-power-compensation equipment in the terminal substation,the port voltage was close to the three-phase symmetry so as to achieve the purpose of reducing asymmetric voltage on the line.The results of theoretical calculation and Matlab simulation analysis show that the as-proposed method can make the voltage unbalance degree at line terminal reach the minimum value and effectively improve the asymmetric state of whole line.