一种适用于风电外送的直流输电控制策略及无功投切方法  

HVDC Control Strategy and Reactive Power Switching Method for Wind Power Delivery

作　　者：李春华 蒋碧松 周勤勇[2] 郭春义 赵成勇 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]中国电力科学研究院,北京市海淀区100192

出　　处：《电网技术》2015年第11期3280-3285,共6页Power System Technology

摘　　要：针对大规模风电经直流外送存在的风电功率频繁波动导致送端系统频率和电压稳定问题,以某地风火打捆经特高压直流外送输电系统为研究对象,提出了一种适用风电功率波动的直流输电控制策略及相应的无功投切方法。首先,利用直流输电系统有功功率、无功功率、直流电流及直流电压的数学关系,推导出有功、无功表示的电压电流整定公式;其次,根据直流系统功率因数变化限制,提出一种功率因数限制无功功率分阶段控制方法,并配合无功补偿装置投切;最后,理论分析了所提策略对直流系统参数的影响。PSCAD/EMTDC仿真表明:直流系统可以快速跟随风电功率波动,功率因数限制无功功率分阶段控制能有效维持交流电压稳定。In view of problems of system frequency fluctuation and voltage stability when large-scale wind power is deliveredwith HVDC, takingwind-thermal-bundledsystem as object, the paper proposesa HVDC control strategy and corresponding reactive switching method suitable for wind power fluctuations. The mathematical relationshipsamong active power, reactive power, DC current and DC voltageareanalyzed theoretically andboth voltage and current of control system settings are deduced. Based on power factor limits, sectionalized reactive power setting curve is developed with reactive power compensation device switching. PSCAD/EMTDC simulation results show DC systempower fluctuatesfollowing wind power quickly and sectionalized reactive power setting curve ensures voltage stability. The control strategies reduce sending end system spinning reserve capacity, frequency regulation unit capacity and switching frequency of reactive power compensation devices, which has certain significance for actual delivery of large-scale wind power project.

关 键 词：风火打捆 直流输电 控制策略 参数分析 

分 类 号：TM721[电气工程—电力系统及自动化]