向拉西瓦水电站供电方案线路过电压计算研究

随着拉西瓦水电站的机组容量不断增大,完全依靠施工工地的电源已无法满足发电机组启动调试和稳定启动所需的电能。因此必须利用现有的输电线路向拉西瓦水电站供电,保证发电机组的顺利投产发电。笔者分析研究了3种通过750kV输电线路向拉西瓦水电站供电方案。建立了相关750kV输变电系统仿真计算模型,计算相关750kV输电线路在不同方案下的潜供电流、恢复电压、工频过电压和操作过电压。通过计算结果的比较和理论分析,从过电压防护角度选择合理的拉西瓦供电方案。

Calculation of Over-voltage on Power Line for Selecting Power Supply Scheme of Laxiwa Hydropower Station

With the expanding of unit capacity of the Laxiwa hydropower station,the existing power supply at the construction field can no longer meet the requirement for starting debugging and stable starting of the generating units. Therefore,increasing power supply from the transmission line to the station is necessary to ensure the normal operation of the hydraulic generators. This paper analyzes three schemes of power supply to Laxiwa hydropower station by 750 kV transmission line,establishes a simulation model of 750 kV transmission/transformation system,and calculates the latent current,recovery voltage,power frequency over-voltage and operation over-voltage of the 750 kV transmission line for the different schemes. A reasonable power supply scheme for Laxiwa hydropower station considering over-voltage protection is hence selected by comparing the calculated results.