基于Park变换和Teager能量算子的晶闸管逆变器保护新方法

Anew Protection Method of Thyristor Inverter Basedon Park Transform and Teager Energy Operator

在高压直流输电系统中,晶闸管逆变器直流差动保护误动于区外故障,以晶闸管逆变器作为研究对象,提出了基于Park变换和Teager能量算子的晶闸管逆变器保护新方法。首先,利用Park变换分析逆变器交流侧电流,建立和直流侧电流的平衡关系,提出主判据;其次,采用逆变器交流侧接地故障的零序电流和逆变器交流侧电流的Teager能量算子作为辅助判据;最后,通过PSCAD仿真将该保护和传统直流差动保护进行比较。结果表明:该保护可有效解决传统直流差动保护误动于区外故障的问题,对于直流差动保护不能动作区内的相间短路故障,该保护方法可正确动作。

In the HVDC transmission system,the DC differential protection of thyristor inverter is misactivated in case of out-of-area faults,and a new method for thyristor inverter protection based on Park transform and Teager energy operator is proposed with thyristor inverter as the research object.Firstly,the Park transform is used to analyze the AC side current of the inverter,establish the equilibrium relationship with the DC side current,and put forward the main criterion,and secondly,the zero-sequence current of the inverter AC side ground fault and the Teager energy operator of the inverter AC side current are used as auxiliary criteria.Finally,the protection and traditional DC differential protection are compared by PSCAD simulation,and the results show that the protection can effectively solve the problem of traditional DC differential protection misoperation in out-of-area faults,and the protection method can operate correctly for phase short circuit faults in the DC differential protection that cannot be operated.