Coordinated Optimal Voltage Control Strategy in Distribution Networks with Multi-Microgrids

Nowadays, microgrids have gained lots of popularity as an effective technology to manage distributed generation (DG). However, with the increasing penetration of DGs and microgrids, the voltage profile in distribution networks might be influenced. To solve the voltage problems in distribution networks while considering the economy of multi-microgrids, a bi-level optimization model is formulated. In the proposed bilevel model, the objective of the upper level is to minimize the power losses of distribution networks, and the objective of the lower level is to maximize the profit of microgrids. The voltage and power exchange at the point of common coupling (PCC) are selected as interrelating variables and a master-slave-splitting method is used to solve the problem. A case study is used to illustrate the coordinated control strategy and the results show that the voltage profile in distribution networks can be improved as well as the economy of microgrids can be ensured.