多直流送端电网低频问题对策研究和工程应用

随着西部电源基地的发展,越来越多的送端电网采用了多直流异步联网的方式。由于负荷相对送出规模较小,送端电网容易出现发电功率损失导致的频率降低稳定问题。分析了多直流送端电网当前面临的低频问题及相关控制系统的技术现状,阐述了利用多直流功率紧急回降措施的频率紧急协调控制系统主要设计思路,从系统总体架构、控制原则及控制策略等方面提出了详细的系统建设方案,最后介绍了该研究成果在西南电网的实际工程应用情况。

Research and Application of Countermeasure for Low Frequency Problem of Multi-DC Transmission Sending Grid

With the development of power supply base in Western China,more and more power grids adopt the method of multi DC asynchronous networking.Due to the small scale of load relative to the DC transmission,frequency instability may occur caused by power loss when the transmission end grid fails.This paper analyzes the current frequency stability problems faced by the multi DC(direct current)transmission sending power grid and the technical status of related control systems,expounds the main design ideas of the frequency emergency coordinated control system which coordinated the use of measures such as multi DC power emergency fallback,and puts forward the detailed construction scheme of the system from the aspects of the overall system architecture,fault criteria and control strategies.Finally,application of the research results in the Southwest Power Grid is introduced.