【摘要】 针对目前混合多馈入直流输电系统(hybrid multiinfeed high voltage direct current,HMIDC)换相失败研究中采用仿真手段而导致计算量大的情况,提出了一种其换相失败免疫水平的快速评估方法。首先针对单馈入电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)系统,提出了计及直流系统一、二次参数影响的基于电压稳定因子(voltage stability indicator,VSI)的换相失败免疫水平快速评估方法,基于CIGRE Benchmark标准直流系统搭建了LCC-HVDC测试算例,仿真分析了所提方法的准确性和快速性;建立了HMIDC系统在LCC-HVDC换流母线处的双母线戴维南等值单馈入分析模型,然后定义了在对应LCC-HVDC换流母线处的等值单馈入电压稳定因子(equivalent voltage stability indicator,EVSI)。在分析换流器功率–电压特性和相角–电压特性的基础上,研究了EVSI的求取方法;最后提出了基于EVSI的HMIDC换相失败免疫水平快速评估方法,基于混合双馈入直流输电系统模型的仿真结果验证了所提方法的有效性。更多还原

【Abstract】 Considering that commutation failure analysis of hybrid multi-infeed HVDC transmission system(HMIDC) is mainly performed with simulation tools, a rapid assessment method of commutation failure immunity level for HMIDC is proposed. Firstly, on the basis of voltage stability indicator(VSI), a rapid determination method of commutation failure immunity level for single-infeed line commutated converter based high voltage direct current(LCC-HVDC) was put forward, and its accuracy was verified by the CIGRE Benchmark Model. Then, an equivalent dual-bus analytical model of HMIDC systems was established, through which an equivalent voltage stability indicator(EVSI) was defined. Meanwhile, the calculation method of EVSI was studied by analyzing converter power-voltage characteristics and phase angle-voltage characteristics. Furthermore, a rapid determination method of commutation failure immunity level for HMIDC systems based on EVSI was set up, and the proposed method was validated by a hybrid dual-infeed HVDC transmission system.更多还原