多馈入交直流混联系统解耦安全域的刻画及应用

Characterization and Application of Decoupling Security Region in Multi-infeed AC/DC Hybrid System

多馈入交直流混联系统具有强非线性、强耦合特征,而直流调整的快速性对控制策略的确定时间提出了较高要求。对于弱受端系统,直流子系统的输电能力较弱,功率的调整范围较小,进行快速功率调制时容易使系统越限,因此需要精细化的控制策略。为了从宏观角度考虑安全特性并实现快速功率精细调制,提出了解耦安全域的概念。对于含有静止同步补偿器(STATCOM)的弱受端多馈入交直流混联系统,基于解耦安全域调整直流功率,并将功率调制问题转化为线性规划问题,可快速得到安全控制策略,并实现直流系统快速功率调制的目的。最后,通过案例研究验证了所提方法的可行性。

A multi-infeed AC/DC hybrid system has the characteristics of strong nonlinearity and strong coupling,and the rapidity of DC adjustment has higher requirements on the determination time of the control strategy.For a weak receiving-end system,the transmission capabi1 ity of the DC subsystem is weak,and the power adjustment range is small,when the fast power regulation is implemented,the system is prone to out of bounds.Therefore,more refined control strategies are needed.In order to control the security characteristic from a macroscopic perspective and realize the fast power fine regulation,the concept of decoupling security region is proposed.As for the weak receiving-end system and multi-infeed AC/DC hybrid system with static var compensator(STATCOM),based on the decoupling security region,the power regulation problem is transformed into a linear programming problem,and the safety control strategy is quickly obtained,so that the purpose of the fast power regulation of the DC system is realized.Finally,the feasibility of the proposed method is verified by case studies.