考虑自动装置控制策略的故障后潮流快速计算方法

大电网交直流故障引发的不平衡功率可能导致局部电网超出稳定极限或中枢母线电压越限,严重情况下会诱发连锁故障或大停电,为了准确模拟故障发生后电网过渡到稳态时的潮流分布情况,确定事故处置策略的有效性,本文提出了一种考虑自动装置控制策略的故障后潮流快速计算方法。根据安控系统、系统保护装置、发电机一次调频、自动发电控制和自动电压控制等自动装置在不同时间尺度上对交直流故障后电网节点有功功率注入量和无功功率注入量的影响,模拟各类自动装置的动作时机和动作策略,形成从故障发生到稳态过程的系统潮流,从而确定过载设备、潮流越限稳定断面和电压越限关键母线,为大电网在线控制决策提供依据。通过对实际电网在线数据的案例分析验证了该方法的有效性和实用性。

Rapid Power Flow Calculation Method After Fault Considering Control Strategy of Automatic Equipment

The unbalanced power caused by AC/DC faults in large power grid may cause local power grid to exceed the stability limit,or the voltage of key buses to exceed the voltage limit.In serious cases,it may lead to cascading faults or large-scale blackout.In order to accurately simulate the power flow distribution when the power grid transits to a steady state after faults and determine the validity of control strategy that controls the unsafe power fault,a rapid power flow calculation method after fault considering the automatic control strategy is proposed in this paper.According to the influence of automatic devices such as safety control system,system protection device,primary frequency modulation of generator,automatic generation control(AGC)and automatic voltage control(AVC)on the active and reactive power injection of grid nodes after AC/DC fault at different time scales,the action timing and strategy of various automatic devices are simulated to form the system power flow from fault occurrence to steady-state process,so as to determine the overload equipment,the stable section of power flow exceeding the limit and the key bus of voltage exceeding the limit,which provides a basis for the online control decision of large power grid.The effectiveness and practicability of the method are verified by the case analysis of the actual online data of power grid.