系统保护中跨区直流频率调制与紧急功率支援的协调控制

为了保障中国特高压交直流混联电网的安全稳定运行，国家电网有限公司积极开展电网系统保护的构建，以提升电网的综合安全防控能力。但随着跨区直流作为灵活控制资源在系统保护中的应用，必须考虑直流功率快速变化会同时对送受端电网造成影响。在梳理中国电网系统保护建设的基础上，系统分析了基于频率响应的直流频率调制对大区电网系统保护的影响，进而从保障电网安全稳定运行和提高跨区控制资源利用效率的角度，提出了综合电网就地和远方信息的直流频率调制与紧急功率支援的协调控制方案，实现大区电网系统保护间的协调动作。最后，基于实际电网仿真算例验证了所提控制方案的有效性。

Coordinated Control of Cross-region DC Frequency Control and Emergency Power Support in System Protection

In order to ensure the security and stability operation of ultra-high voltage (UHV) AC/DC power grid in China, State Grid Corporation of China actively constructs the system protection of power grid to improve the comprehensive security prevention and control capability. However, with the application of cross-region DC as a flexible control resource in the system protection, it must be considered that the rapid change of DC power will affect the sending-end and receiving-end power grids simultaneously. On the basis of sorting out the system protection construction of power grid in China, the impact of frequency response based DC frequency control on the system protection of large-scale power grids is systematically analyzed. From the perspectives of ensuring the security and stability operation of the power grid and improving the efficiency of cross-region resource utilization, a coordinated control scheme of DC frequency control and emergency power support for integrating local and remote information of the power grid is proposed to achieve the coordinated operation between the system protections of large-scale power grids. Finally, the effectiveness of the proposed control scheme is verified based on actual power grid simulation examples.