基于二阶锥优化的交直流系统多目标最优潮流研究

为解决广域大范围内新能源的并网和消纳问题,柔性直流电网技术得到了快速的发展,已经发展成为了直流环网的形式.直流环网具有多条冗余线路,能更好更灵活地调度各发电单元和线路之间传输的功率.针对柔性直流电网的特点,提出一种基于二阶锥优化和超效率数据包络分析法的交直流互联系统最优潮流计算方法.基于含VSC-HVDC的交直流系统稳态模型,建立了综合考虑环境因素和系统网络损耗的多目标最优潮流模型;采用二阶锥和IPOPT(内点法)相结合的交替求解方法将其转化为二阶锥凸优化问题;再通过SE-DEA从Pareto最优解集中选取出有效近似度最高的有效折中解.基于修改的IEEE 14、IEEE 30节点算例结果验证了所提方法的有效性、准确性,能够很好地解决含VSC-HVDC交直流系统最优潮流问题.

Research on multi-objective optimal power flow of AC/DC system based on second-order cone optimization

In order to solve the problem of grid connection and consumption of new energy in a wide area, the flexible DC grid technology has developed rapidly and has developed into a form of DC ring network. The DC ring network has multiple redundant lines, which can better and more flexibly schedule the power transmitted between each power generating unit and the line. Aiming at the characteristics of flexible DC grid, an optimal power flow calculation method based on second-order cone optimization and super-efficiency data envelopment analysis is proposed. Firstly, based on the steady-state model of AC/DC system with VSC-HVDC, a multi-objective optimal power flow mathematical model with AC/DC system net loss and pollutant emission as the objective function is established. Then, the second-order cone and IPOPT (internal point method) are combined to solve the second-order cone-convex optimization problem. Finally, the effective compromise solution, which is with the highest effective approximation degree, can be selected from the Pareto optimal solution which are set by the SE-DEA. Based on the modified IEEE14 and IEEE30 node examples, the effectiveness and accuracy of the proposed method are verified, which can solve the optimal power flow problem of VSC-HVDC AC/DC system.