多类型电源汇集直流外送系统切机策略优化研究

A Study on the Optimization of Generator Tripping Control of the HVDC Sending System with Multi-Type Power

多类型电源汇集直流闭锁切机后可能衍生出系统稳态电压越限问题,且不同切机组织方式的影响不同,同时各类电源的切机控制代价不同,须进一步深入研究兼顾系统安全性与控制经济性的优化切机策略。分析了直流闭锁切机后系统电压的计算方法及其影响因素,提出了综合事故后关键母线稳态压升与控制总代价的切机策略优化方法及实现步骤。首先在满足系统暂态功角、频率、电压稳定的条件下,确定直流故障后所需总切机量;其次根据切除不同类型电源对事故后系统稳态压升的影响,对各类电源的切机顺序进行排序;最后基于事故后系统稳态压升的约束,以控制总代价最小为优化目标,最终确定优化后的切机策略。实际电网仿真结果验证了所提优化控制策略的合理性与有效性,兼顾了系统的安全性与经济性。

The system steady-state voltage overrun may arise after HVDC blocking with various types of power supply,and impacts of the different cut-off organization mode is different,and the cut-off control cost of various types of power supply is also different.Therefore,it is necessary to study the optimal tripping strategy which can take into account both system safety and control economy.This paper analyzes the calculation method and influence factors of the system voltage after the generators tripping because of the HVDC blocking.The optimization method and implementation steps of the generator tripping control strategy are proposed,which integrate the steady-state voltage rise of the key bus with the total control cost after the accident.First,the total generators tripping quantity after HVDC blocking is determined under the condition that the transient power angle,frequency and voltage of the system is stable.Second,the tripping sequence of all kinds of power sources is sequenced according to the influence of tripping different power sources on the steady-state voltage rise after the accident.Finally,based on the constraint of the system steadystate voltage rise after the accident,the optimized tripping generators strategy is finally determined with the minimum total control cost as the optimization objective.The simulation results of the actual power grid,taking into account the safety and economy of the system,have verified the rationality and effectiveness of the proposed optimal control strategy.