Implementation of distributed energy resources (DERs) has led to a decrement in the cost of supplying demand in distribution networks. Integration of DERs in the forms of micro-grids (MGs) is a solution to enhance the operation of these resources in the low voltage networks. To meet the demand by MG operator, both technical and economic characteristics as well as the prices offered by retailers are considered to schedule DERs optimally. In these networks, the profit of retailers is maximized by power trading with MGs and optimally purchasing the energy from wholesale markets. Due to the existence of several retailers and MGs in active distribution networks (ADNs), hierarchical decision-making frameworks are needed to model their operation problem. For this purpose, a bi-level optimization technique is proposed in this paper to model the operation problem of retailers and MGs as decision-making variables in distribution networks in the upper and lower levels, respectively. To solve the proposed model, multi-objective particle swarm optimization (MOPSO) algorithm is used. The proposed model and its solution method are applied to a hypothetical distribution network with several retailers and MGs to validate the theories and discussions. Numerical results show that the maximum capacity of DG and the amount of demand have an important effect on this decision and the prices of purchased power from wholesale markets determine the amount of retailers’ offers to MGs.

分布式能源（DERs）的实施导致配电网络中满足需求的成本下降。以微电网（MG）形式集成DER是解决方案，可增强低压网络中这些资源的运行。为了满足MG运营商的需求，技术和经济特性以及零售商提供的价格都被认为可以最佳地调度DER。在这些网络中，通过与MG进行电力交易并从批发市场最佳地购买能源，可以使零售商的利润最大化。由于主动分销网络（ADN）中存在多个零售商和MG，因此需要分层的决策框架来对其运营问题进行建模。以此目的，本文提出了一种双层优化技术，将零售商和大型企业的运营问题分别建模为上层和下层分销网络中的决策变量。为了解决该模型，使用了多目标粒子群优化算法。所提出的模型及其求解方法被应用于具有多个零售商和MG的假设分销网络，以验证理论和讨论。数值结果表明，DG的最大容量和需求量对该决策有重要影响，批发市场的购买力价格决定了零售商对MG的报价量。为了解决该模型，使用了多目标粒子群优化算法。所提出的模型及其求解方法被应用于具有多个零售商和MG的假设分销网络，以验证理论和讨论。数值结果表明，DG的最大容量和需求量对该决策有重要影响，批发市场购买电力的价格决定了零售商对MG的报价量。为了解决该模型，使用了多目标粒子群优化算法。所提出的模型及其求解方法被应用于具有多个零售商和MG的假设分销网络，以验证理论和讨论。数值结果表明，DG的最大容量和需求量对该决策有重要影响，批发市场的购买力价格决定了零售商对MG的报价量。