摘要
为抑制后续换相失败以及改善高压直流输电系统故障后的恢复能力,首先构建关于逆变器消耗无功功率的隐函数,发现直流电流是影响逆变器消耗无功功率的主要因素,并以此分析首次换相失败及恢复期间逆变器消耗无功的暂态变化过程,得出若交流系统无法支撑逆变器所需的无功功率,将导致换流母线电压的进一步跌落、关断角下降,极易引发后续换相失败。其次定量分析换相失败后交直流系统间产生的无功不平衡量对直流电流的影响,并推导直流电流指令值优化计算公式,提出考虑无功功率影响的后续换相失败抑制策略。最后以CIGRE标准模型为基础进行仿真测试,验证了该策略在不同故障条件下对后续换相失败抑制的有效性。
In order to suppress subsequent commutation failure and improve the recovery ability of HVDC transmission system after failure,the paper first establishes the implicit function of reactive power consumption from an inverter,pointing out that DC current is the main factor affecting the reactive power consumption from the inverter.After that,the transient change process of the reactive power consumption during the first commutation failure and recovery is analyzed.It is concluded that if AC system cannot support the reactive power required by the inverter,it will lead to the further drop of the converter bus voltage and turn-off angle reduction,easily causing the subsequent commutation failure.Secondly,the influence of reactive power unbalance on DC current generated between AC and DC system after the commutation failure is quantitatively analyzed,the optimal calculation formula of DC current command value is derived,and the suppression strategy for the subsequent commutation failure considering the influence of the reactive power is proposed.Finally,simulation tests are done based on the CIGRE standard mode,and the results verify the effectiveness of this strategy to suppress the subsequent commutation failure under different fault conditions.
作者
樊庆东
尹纯亚
李凤婷
苏常胜
FAN Qingdong;YIN Chunya;LI Fengting;SU Changsheng(College of Electrical Engineering,Xinjiang University,Urumqi 830047,China)
出处
《智慧电力》
北大核心
2023年第11期98-105,共8页
Smart Power
基金
国家重点研发计划资助项目(2021YFB1507000)。
关键词
高压直流输电
无功功率
直流电流
换流母线电压
关断角
后续换相失败
HVDC transmission
reactive power
direct current
converter bus voltage
turn-off angle
subsequent commutation failed
