考虑换流器功率传输裕度的直流配电网优化重构研究

Research on Optimal Reconfiguration of DC Distribution Network Considering Converter Power Transmission Margin

直流配电网中可变负荷功率波动大,当换流器功率传输裕度(可通过自适应下垂系数表征)较小时,换流器传输功率易达限值,失去对潮流变化的响应能力。为解决上述问题,将换流器自适应下垂系数、网络损耗、节点电压偏移作为直流配电网网架结构优化的寻优目标,经隶属函数模糊化处理得到目标函数,并采用牛顿迭代法对计及换流器准确损耗模型的直流配电网进行潮流计算,最终由二进制粒子群算法迭代求得上述指标综合最优的直流配电网网架结构。在修改后的IEEE33节点直流配电网中验证了其正确性和有效性。

The power of variable loads in the DC distribution network fluctuates greatly.When the converter power transmission margin(which can be characterized by self-adaption droop coefficient)is small,the converter transmission power is easy to reach the limit,and the ability of responding to the change in power flow will be lost.To cope with above mentioned problem,the converter adaptive droop coefficient,network loss,and nodal voltage offset were taken as the optimizing goals of the DC distribution network structure optimization.The objective function was obtained through the membership function fuzzy processing,and by use of Newton-Raphson method the power flow calculation of the DC distribution network,in which the accurate loss model of the converter was taken account,was carried out.Finally,by means of the iteration of binary particle swarm algorithm the DC distribution network frame structure with synthetical optimum of above mentioned indicators was obtained.The correctness and effectiveness of the proposed DC distribution network frame structure are verified by the modified IEEE33 bus DC distribution network.