现有自动电压控制(automatic voltage control,AVC)策略难以保证220 kV变电站充分利用无功电压调控设备兼顾上下层电网无功电压调控的需求,特别在小方式下,省地电网无功电压调控失配问题突出。提出了一种实现上下层电网协调控制的AVC去失配策略。结合省地电网的管理权限、调控目标和AVC策略的分析了省地AVC在220 kV变电站形成无功电压调控失配的机制,通过等值模型反映的无功电压特性揭示了关口电压是解决失配问题的关键指标,将反映上下层电网电压调控状态的关口电压加入到AVC就地电压校正策略中构成了三维去失配判据,以实现常规方式220 kV变电站优先协助下层电网进行区域电压调控,小方式220 kV变电站优先协助上层电网进行区域无功调控的去失配策略。实例仿真证明了去失配策略的有效性。
It is difficult for existing automatic voltage control (AVC) strategy to ensure fully utilization of votlage/var regulation devices in 220kV substation to meet both demands of votlage/var control from upper- and lower-level power networks, especially under light load flow operation mode the mismatching of votlage/var control between provinical and district power networks happens. Based on administration authority of provinical and district power networks, the objective of votlage/var and AVC strategy, the mechanism of mismatching of AVC-based voltage and reactive power control occurred in 220 kV substation is analyzed, and an anti-mismatching strategy that can implement coordinated control of votlage/var between provincial and district power networks is proposed. Through the characteristics of vokage and reactive power reflected by equivalent assessment model, it is revealed that the boundary voltage is the key to solve the mismatching, and the boundary voltages reflecting the voltage control states of upper- and lower-level power networks are added into local votlage correction strategy of AVC to compose a three-dimensional anti-mismatch criterion, thus under routine operation mode the votlage/var regulation devices in 220kV substation can preferentially help the lower-level power network to carry out district voltage control and under the light load flow mode the votlage/var regulation devices in 220kV substation can preferentially help the upper-level power network to execute anti-mismatch strategy for regional votlage/var control. Simulation results of actual case show that the proposed anti-mismatch strategy is effective.