Agent-based Distributed Finite-time Secondary Control of Energy Storage Systems in Microgrids — Controller Hardware-in-the-Loop Validation

In this paper, we proposed a novel agent-based distributed secondary control strategy for energy storage systems (ESSs) in islanded ac microgrids. Agents are designed to deploy the finite-time consensus algorithm with non-linear law by receiving limited information from local and neighbor agents. The ESSs with the proposed control scheme can achieve the balance of state-of-charge in a good performance with small power overshoot and fast converge speed. A Controller Hardware-in-the-Loop microgrid platform is provided with physical systems in OPAL-RT and the agent system in a Raspberry Pis cluster. This platform enables the investigation of interactions among microgrid entities, control systems, and communication networks. An islanded ac microgrid with the proposed control scheme has been implemented on the platform. The experiment results demonstrate the performance and advantages of the proposed method.

I. Introduction

In the hierarchical control of a microgrid (MG), the secondary and tertiary control level can be implemented in either centralized or distributed fashions. In this paper, we focus on the secondary control level, where a distributed control scheme for multiple ESSs in islanded MGs is studied. The MG central controller collects all the information of the distributed generators and then sends back the control signals to each DG. As an alternative way, the distributed secondary control of MGs has been widely investigated due to its various advantages as enhancing reliability, scalability and privacy [1], [2].