烟台220 kV沈福线与嵛新线开断改接规划设计

Opening-Reconnecting Plan and Design Between Yu-Xin and Shen-Fu Transmission Line of 220 kV

烟台电网220 kV岗嵛站最高负荷为180 MW,220 kV新港站最高负荷为170 MW,由220 kV嵛福线和汤新线串供。若220 kV汤新线、嵛福线任一线路故障跳闸,则余下另一回线路带220 kV岗嵛站和新港站共350 MW负荷运行,220 kV嵛福线、汤新线允许电流均为845 A,线路超流12%。若在220 kV沈福线、嵛新线交叉跨越处进行开断、改接后,将形成220 kV沈余站到岗嵛站、220 kV新港站到福山站两回线路。经计算,潮流、稳定、N-1方式下潮流均无问题。但在施工期间,需220 kV沈福线、嵛新线、霞沙线3条线路同时停电,对电网安全运行影响较大。为此,设计人员提出3个设计方案,并进行技术经济比较,最终确定同塔双回异侧T接的最优设计方案,并付诸实施,迎接夏季用电高峰。

The maximum load of 220 kV Gang-yu substation and 220 kV Xin-gang substation are up to 180 MW and 170 MW respectively. Both substations are serially connected to 220 kV Yu-fu line and Tang-xin line. In case that one of the 220 kV Tang-xin line and Yu-fu lines has been tripped after fault, the rest will run both 220 kV Gang-yu substation and 220 kV Xin-gang substation, and the maximum load may be over 350 MW. The permissible currents of 220 kV Yu-fu line, Tang-xin line are 845 A. As a result, it will cause the current surpassing the permission of the line over 12%. Consequently, the proposal which reconnects the lines after the crisscross lines are unfolded and makes two new lines, one of which is from 220 kV Shen-yu substation to Gang-yu substation and the another is from 220 kV Xin-gang substation to Fu-shan substation is developed. According to this proposal＇s computation, there are no negative effects on the power flow, stability under the N-I operation condition of grid. However, there are numbers of negative influences on grid during the project construction because the 220 kV Shen-fu line, Yu-xin line and Xia-sha line must be cut off simultaneously. For this reason, three new proposals are developed. By technical and economic comparison of the proposals, the proposal of T-link on another side of the one-tower double-ciwuits is chosen as the optimal one to be applied to supply the peak load in summer.