Distributed Control of Islanded Series PV-Battery-Hybrid Systems with Low Communication Burden

To better integrate distributed energy sources, the series photovoltaic-battery-hybrid system has been proposed. However, the state-of-the-art control highly relies on the communication, by which real-time control variables should be transmitted among all converters. To overcome this, a novel distributed control method is proposed in this paper. Firstly, a PQ decoupling control is introduced, which enables the control of individual converters with only local measurements. Then, a reactive power distribution method is developed to achieve approximately equal power sharing among the converters. Additionally, two anti-over-modulation loops are developed to address the over-modulation issue. With the proposed method, only the total power of the series system should be transmitted, and the communication burden can be significantly reduced. Simulation and experimental results have validated the effectiveness of the proposed method.