配电项目最大供电能力及增供电量效益的评估

The Evaluation for Maximum Power Supply Capability and Benefit of Increasing Power Supply of Distribution System

提出一种配电网供电能力评估方法及配电网项目增供电量效益的预评估方法。基于主变负载率均衡的原则,以变电站负载率为自变量,以系统最大供电能力为目标函数,以主变N-1故障情况下负荷转移不超过变电站之间联络线传输容量以及变压器自身容量裕度为约束条件,构建配电系统最大供电能力评估模型,并提出基于线性规划的求解方法以简化运算。以项目投运前后系统最大供电能力与负荷预测值确定增供电量效益评估模型。既考虑了联络线及变压器容量的充分利用,同时兼顾了变电站负载均衡,保证了系统的安全供电和供电质量;既评估了配电系统最大供电能力,也实现了对配电系统项目增供电量效益的评估。通过实例分析,验证了该模型的有效性。

A new method to evaluate the power supply capability of distribution system and a preevaluation method for efficiency of increased power supply of the power distribution network projectare proposed.Based on the principle of main transformer’s load ratio balance,the load rate oftransformer substation is used as the independent variable,the maximum power supply capacity of thesystem is used as the objective function,the constraint condition is that the load transfer is not morethan the transmission capacity of the tie line between the substation and the capacity margin of thetransformer in the case of transformer N?1,and a solution method based on linear programming isproposed to simplify the computation.Efficiency evaluation model of increased power supply isdetermined on the maximum power supply capacity of the system before and after the project put intooperation and Load forecast value.The evaluation method not only considers the full use of the tie lineand transformer capacity,but also takes into account the load balance of the substation,which ensuresthe security of the system and the quality of the power supply.The evaluation of the benefit ofincreasing power supply in the power distribution system is also realized.The effectiveness andcorrectness of the model has been verified through the practical examples.