LCL型高压直流输电系统中换流变压器损耗的仿真研究

Simulation Study of Converter Transformer Loss in LCL-HVDC System

摘要: 针对基于电网换相换流器的高压直流输电(LCC-HVDC)系统中存在的换流变压器噪声大、逆变侧换相失败等问题,提出了采用LCL型换流器的高压直流输电系统。在PSCAD中建立荆门—上海±500 kV直流输电的LCC-HVDC和LCL-HVDC系统的仿真模型,在该模型中测量了换流变压器阀侧绕组的谐波电流,研究了换流变压器的负载损耗。通过研究发现相较于LCC-HVDC系统,LCL-HVDC系统中的换流变压器的负载损耗降低了约38.1%。

Abstract: In order to solve the problems existing in traditional HVDC transmission based on grid commutation converter（LCL-HVDC）system, such as high noise of converter transformer and commutation failure of inverter side, a HVDC transmission with LCL converter system is proposed. In this paper, the simulation models of LCC-HVDC and LCL-HVDC system of Jingmen-Shanghai ± 500 kV DC transmission are established in PSCAD. In this model, the harmonic current of valve side winding of converter transformer is measured, and the load loss of converter transformer is studied. Through the research, the load loss of converter transformer in LCL-HVDC system is reduced by 38.1% compared with LCC-HVDC system.