摘要
输电线路电压等级越高,地线上的电能损耗就越大,如何降低地线损耗意义重大。分析了电能在地线中产生损耗的原因,通过EMTP仿真计算了在各种情况下电能损耗,比较了采用地线分段后的效果,得出:对750 kV输电线路采用分段绝缘的绝缘方式,有效地减小地线上的感应电流,使地线的损耗降抵为地线两端直接接地时的99%以上;三相负载平衡程度越小,地线产生损耗会越大,应尽量保证系统三相负载平衡;适当调整接地电阻的大小可以优化地线电能损耗;输电线路长度增加,地线损耗和地线上的感应电压也增大,应选取合适的分段距离,使地线损耗降低到最小。
With the increasing of voltage grade of power system, the power loss at ground wire becomes more and more remarkable. Therefore, research on its reduction has great significance for economy and energy saving. The cause of the electric energy loss has been analyzed. The power loss reduction mall occasions and the validity to ground line sectionalization was calculated using EMTP program. It is determined that application of subsectional insulation on 750 kV transmission line can considerably reduce the inductive current on ground wire, reducing the power losses by 99% than that of direct grounding at two ends. Effort shall be made to keep balance of loads between three phases as the unbalanced load leads to more power losses. Proper adjusting section distance can reduce the power losses at ground wire to minimum.
出处
《电瓷避雷器》
CAS
2008年第1期18-21,共4页
Insulators and Surge Arresters
