Frequency restoration in microgrids by means of distributed control with minimum communication requirements

This paper presents a solution for improving the functionality and reliability of the frequency restoration process in autonomous microgrids (MG), which is known as secondary control. The main advantage of the proposed method consists in not requiring extensive communication between the involved regulating units. Due to the integrative action of the secondary control level, the distribution of multiple controllers throughout the system is unpractical, without a synchronization mechanism, and therefore the most adopted solution is a centralized control with communication links with the associated regulating units inside the MG. However, the reliability of the control process strongly depends of the communication infrastructure. For this reason, this paper tackles the distributed control method and improves it to make it practical and minimizing the communication requirements. The proposed concept is assessed on a laboratory experimental microgrid.