直流换相安全性与混联系统同步稳定性的量化分析与协调控制

Quantitative Analysis and Coordination Control for DC Commutation Security and Synchronism Stability of AC/DC Hybrid Power System

定量地分析电力系统工况与故障场景对直流换相安全性及系统同步稳定性的影响,提出设备保护与系统保护之间协调优化的思路。基于反映直流换相安全性的量化指标及反映电力系统同步稳定性的扩展等面积准则(EEAC)裕度指标,揭示了两者之间复杂的相关性。根据各控制措施对于提升换相安全性及同步稳定性的性能代价比,协调优化控制策略,以最小的控制代价同时保证直流换相安全与系统同步稳定。通过对交直流互联的同步系统以及直流互联的异步系统的仿真,验证该换相安全裕度的合理性,以及协调优化策略的有效性。

The influence of operating conditions and fault scenarios on DC commutation security and synchronism stability is analyzed quantitatively.The idea of coordination and optimization between the equipment protection and the system protection is put forward.The quantitative index reflects the commutation security of DC systems,and the extended equal-area criterion(EEAC)margin index reflects synchronism stability of power systems.Based on these two quantitative indices,the complex correlation between the two stability is revealed.According to the performance cost ratios of the control measures for improving commutation security and synchronism stability,the control strategy is coordinated and optimized to ensure the DC commutation security and system synchronism stability with the minimum control cost.Based on the simulations of the AC/DC interconnected synchronous system and DC interconnected asynchronous system,the rationality of the commutation security margin index and the effectiveness of the coordinated optimization strategy are verified.