The optimal operation model of AC/DC distribution network with energy router (ER) is essentially a nonconvex nonlinear programming (NLP) problem. In order to improve the feasibility of solving the model, a convex approximation algorithm is proposed in this work. The steady-state model of ER is developed with considering the loss characteristics and multiport coordinated control strategy. It is embedded in the optimization formulations of AC/DC network as basic operating equations. Then, using second-order cone relaxation technology, the power flow equations of AC and DC distribution networks are convexly relaxed. On this basis, the highly nonlinear operating model of ER is linearized by introducing a successive approximation approach. Therefore, the original NLP problem is transformed into the convex programming problem and the solution efficiency is improved. Meanwhile, an iterative solution algorithm is developed to ensure the accuracy of the convex approximation approach. Simulation results verify the feasibility and efficiency of the proposed algorithm.

中文翻译：

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带能量路由器的交直流配电网凸逼近算法

带有能量路由器（ER）的交直流配电网络的优化运行模型本质上是一个非凸非线性规划（NLP）问题。为了提高求解模型的可行性，本文提出了一种凸逼近算法。考虑损耗特性和多端口协调控制策略，建立了ER稳态模型。它作为基本操作方程嵌入到 AC/DC 网络的优化公式中。然后，利用二阶锥弛豫技术，对交直流配电网的潮流方程进行凸弛豫。在此基础上，通过引入逐次逼近方法，将ER的高度非线性运行模型线性化。所以，将原来的NLP问题转化为凸规划问题，提高了求解效率。同时，开发了一种迭代求解算法来保证凸逼近方法的准确性。仿真结果验证了所提算法的可行性和有效性。