摘要
为适应并联型多端直流输电系统更灵活、更精准的电压、电流控制要求,对其控制保护策略进行了研究,提出了一种适用于并联型多端直流输电系统的控制策略和一种直流线路短路故障下不依赖直流断路器的故障清除策略,并研究了交流系统短路故障时多端直流系统与2端直流输电系统的不同特征。对一个并联型4端双极直流输电系统进行仿真分析,结果显示所提出的控制策略可行、有效,控制模式切换不会引起系统明显扰动,且在直流线路短路故障时可摆脱对直流断路器的依赖。相比2端系统,多端系统逆变站交流侧短路故障对系统的冲击更严重。
To fulfill the growing requirements of flexibility and precision in voltage and current control of Multi--terminal DC （MTDC） power transmission systems, we studied the control and protection strategies of MTDC transmission systems and presented a new control strategy for parallel-MTDC systems. We also proposed a strategy for clearing DC line fault in MTDC systems not relying on high voltage DC circuit breaker. Moreover, the fault characteristics of MTDC systems under AC system faults were studied and compared with those of the traditional two-terminal DC systems. We established a numerical model of a parallel bipolar MTDC systems with 4 terminals. The simulation proves that the proposed strategies are effective and feasible, and disturbance can not remarkably be caused by switching control modes, showing that the systems under DC faults needs no DC breaker. It is also shown that, compared with the traditional two-terminal DC systems, the shock caused by AC systems fault on the inverter side is more severe for MTDC systems.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2013年第11期2721-2729,共9页
High Voltage Engineering
