考虑可靠性的中压配电系统供电能力评估

针对现有供电能力评估方法采用N-1安全准则作为刚性约束而产生过量裕度的问题,提出了考虑供电可靠性的中压配电系统供电能力评估方法。首先,构建以最大供电能力为目标、供电可靠性为主要约束的非线性数学模型;其次,结合馈线分区理念并考虑负荷的时序特性,发展了含主变的配电系统可靠性评估序贯蒙特卡洛模拟法;在此基础上,基于典型用户类型及其负荷之间的解析关系,通过增供负荷及其用户数量将供电能力与可靠性进行关联;最后,基于遗传算法提出了满足某一确定供电可靠性指标要求的配电系统供电能力优化求解方法。算例结果表明,该方法能够有效释放配电系统供电能力,挖掘供电潜力。

Power Supply Capability Evaluation of Medium Voltage Distribution System Considering Reliability

The existing power supply capability evaluation method based on N-1 safety criterion as rigid constraint can bring about excess margin. To remedy the situation, a power supply capability evaluation method of medium voltage distribution system considering power supply reliability is proposed. Firstly, a nonlinear mathematical model is developed with total supply capability as the objective and power supply reliability as the main constraint. Secondly, by referring to the notion of feeder partition, the sequential Monte Carlo simulation method is used to evaluate the reliability of distribution system including the main transformer. And based on the analytic relationship between the typical type of the users and its load, a relationship between the power supply capability and reliability is built by increasing the load and the number of users. Finally, based on the genetic algorithm, a power supply capability optimal solution method is designed to meet the demand of a certain reliability index. Results of the numerical example indicate that the method can effectively release the power supply capability of distribution system and tap the potentialities of power supply. This work is supported by National Natural Science Foundation of China(No.51477116)and State Grid Corporation of China.