摘要
直流换流站无功补偿配置及控制策略优化对于提高直流输电工程运行可靠性及经济性具有重要意义。论文针对送端换流站无功补偿设备投切频繁造成断路器使用寿命急剧下降的问题,结合现有无功控制方案,根据相关公式理论推导直流输送功率、换流母线电压与系统无功交换量之间的关系,深入探究直流输送功率变化与交流电压波动对无功单元投切次数的影响。根据V-Q灵敏度计算原理,基于对西北地区典型送端换流站配套电源无功补偿能力的研究,探究提高无功控制参考值与无功控制死区值的可行性及实现方式,针对直流系统高功率运行时并联电容器投切频繁问题突出而低功率运行时交流滤波器最小投入组数受到限制的特点,采用直流系统高功率运行时增大无功控制参考值与死区值而低功率运行时保持原方案的控制模式,并运用PSASP仿真验证该策略可有效减少无功单元的投切次数,为直流送端换流站无功控制优化策略的实践应用提供理论依据。
Reactive power compensation configuration and control strategy optimization of DC converter stations are of great significance to improve the operation economy and reliability for DC transmission projects.In view of such problem as dramatic reduction of operation life of circuit breaker due to the frequent switching of reactive power compensation device converter station at the sending end,in this paper,the influence of DC transmission power variation and AC voltage fluctuation on the switching number of reactive power unit is studied deeply in accordance with existing reactive power control scheme and the relations among DC transmission power,commutating bus voltage and reactive power exchange capacity of system which is derived by the related formula theory.The feasibility and achievement mode on improving reactive power control reference value and dead zone value is studied in accordance with the calculation principle of V-Q sensitivity and on the base of the study of reactive power compensation ability of fitted power of converter station at the typical sending end in the northwest area of China.As for such features as the limit of minimum switching number of AC filter when the power operation is reduced due to frequent switching of shunt capacitor during high power operation of DC system,the reference value and dead-time value of reactive power control are increased at high power operation of DC system,while the control mode of the original scheme is maintained at low power operation.It is shown by the simulation results in PS ASP that the strategy can reduce the switching number of reactive power unit effectively and provide the theoretical evidence for the practice and application of reactive power optimization strategy of converter station at the sending end.
作者
邹洪森
惠子珈
刘志远
于晓军
郝治国
ZOU Hongsen;HUI Zijia;LIU Zhiyuan;YU Xiaojun;HAO Zhiguo(Maintenance Branch of State Grid Ningxia Power Company,Yinchuan 750001,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《电力电容器与无功补偿》
北大核心
2019年第5期66-73,共8页
Power Capacitor & Reactive Power Compensation
基金
国家自然科学基金项目（51577148）
关键词
高压直流输电
送端换流站
无功补偿
频繁投切
控制参数
控制策略
HVDC power transmission
rectifier station
reactive power compensation
frequent switching
control parameters
control strategy
