摘要
随着特高压直流输电系统送端电网新能源渗透率的日益提高,系统惯量水平大幅降低,频率稳定问题日趋突出。该文综合考虑特高压直流系统与传统同步电源的频率响应特性,提出了一种主动支撑送端系统频率的多时间尺度协调控制策略,在提升系统频率稳定性的同时实现调频资源的合理利用。结合送端系统最大调频备用容量和扰动后的不平衡功率,分析了不同场景下的系统调频需求,提出了特高压直流系统的多时间尺度调频控制策略,使其同时具备惯量支撑与一次调频的能力;结合同步机一次调频最大备用容量,设计了特高压直流系统调频控制策略的死区值,实现了不同场景下特高压直流系统惯量支撑与一次调频作用的自适应切换,在保证送端交流系统频率稳定的同时实现同步机调频能力的充分利用;在此基础上,分析了不同场景下频率支撑协调控制策略的动态响应特性,进一步凸显了其相比于现有控制策略的优越性。最后,基于RTLAB实时数字仿真平台搭建了新能源基地经特高压直流送出系统的仿真模型,验证了所提频率主动支撑协调控制策略的有效性。
With the increasing penetration of renewable sources in the power grid at the sending terminal of an ultra-high voltage direct current transmission system(UHVDC),the system inertia level is significantly reduced,and the frequency stability problem is becoming more and more prominent.By integrating the frequency response characteristics of the UHVDC system and the traditional synchronous power sources,this paper proposes a multi-timescale coordinated control strategy to actively support the frequency of the sending terminal system,achieving the reasonable utilization of the frequency modulation resources and improving the frequency stability of the system.Combining the maximum frequency modulation reserve capacity of the sending terminal system and the unbalanced power after a disturbance,the system frequency demand under different scenarios is analyzed,and a multi-timescale frequency modulation control strategy for the UHVDC system is proposed so that it has the capability of both inertial support and primary frequency regulation.With the maximum spare capacity of the primary frequency regulation of the synchronous machine,the dead zone value of the frequency regulation control strategy of the UHVDC system is designed,realizing the adaptive switching of the inertia support and the primary frequency regulation of the UHVDC system under different scenarios,which achieves the full utilization of the frequency regulation capacity of the synchronous machine while ensuring the frequency stability of the AC system at the sending terminal.On this basis,the dynamic response characteristics of the coordination control strategy under different scenarios are analyzed,further highlighting its superiority over the existing control strategies.Finally,a simulation model of the renewable sources via the UHVDC transmission system is built on the RTLAB real-time digital simulation platform,verifying the effectiveness of the proposed frequency-supported coordination control strategy.
作者
辛业春
张嘉新
江守其
王威儒
王拓
王延旭
XIN Yechun;ZHANG Jiaxin;JIANG Shouqi;WANG Weiru;WANG Tuo;WANG Yanxu(Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology,Ministry of Education(Northeast Electric Power University),Jilin 132012,Jilin Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2023年第12期5089-5097,共9页
Power System Technology
基金
国家电网公司总部科技项目(5108-202299258A-1-0-ZB)。
关键词
特高压直流系统
惯量支撑
一次调频
协调控制
频率稳定性
UHVDC
inertia support
primary frequency regulation
coordinated control
frequency stability
