特高压直流阀厅金具选型与结构优化

Fittings Selection and Optimization in UHVDC Valve Hall

随着直流输电电压等级越来越高,换流阀厅内设备越来越密集,尤其是±1 100 kV电压等级阀厅,对阀厅内金具的绝缘要求更加严苛。通过有限元数值计算,可以得到阀厅内金具表面电场,判断金具是否满足绝缘设计。阀厅内部交直流混杂,针对阀厅金具,分别采用静电场与瞬态电场进行计算,计算结果表明,阀厅金具可以通过直流电压下的电场计算对瞬态结果进行预估。根据电场计算结果进行金具选型,并对金具结构参数进行优化,分析得出影响场强的主要参数,将仿真计算紧密嵌入金具设计中,缩短设计周期,降低生产成本。

In past few years,the voltage level of HVDC transmission system has been increased dramatically andequipment in the valve hall has become denser. Therefore,insulation requirements should be more stringent,espe-cially for the ±1 100 kV UHVDC valve hall. To testify if the fittings can fulfill the insulation constraints,we get theelectric field distribution of the fittings by using finite element numerical calculation. However,the mixture of theDC and AC voltage in valve hall makes the problem very complex. We take both of the electrostatic and transient elec-tric field method,and the results have shown the transient electric field can be predicted by calculating the field in-tensity in the condition of direct voltage. For researchers,electric field computational results will give a guideline onhow to choose a proper fitting and how to optimize structural parameters of the fitting. Furthermore,in the process ofcomputation,main structural parameters that have a strong effect on field intensity can be concluded. By embeddingthe simulation calculation in the fitting design,the design period will be shorten and substantial cost reductions canbe attained at the same time.