Finite-Time Consensus Pinning Control Method for Multiple Inverters–Paralleled Photovoltaic Microgrid

Abstract

Multiple inverters–paralleled photovoltaic microgrid is a typical cyber-physical system with varying line impedances and unsynchronized nodes that result in unbalanced power sharing and are prone to cause circulating current. Therefore, a complex network based on a finite-time consensus pinning control method for microgrids is proposed in this paper. First, the distributed generators are regarded as agent nodes, and a small-world network model is established based on complex network theory. To overcome the subjectivity of relying on expert experience to select pinning nodes in previous pinning control methods, a selection algorithm that uses only nodes with large out-degree as pinning nodes is proposed to reduce the communication bandwidth requirement of the system. Second, the finite-time consensus algorithm and the pinning control method are integrated to form a finite-time consensus pinning control method. By introducing voltage and frequency correction in the primary control layer, the finite time consensus pinning control method is applied to design distributed secondary controllers. The finite-time stability of the system is analyzed through Lyapunov stability theory. Finally, a hardware-in-the-loop simulation platform is built in StarSim HIL. Compared to the traditional finite-time control method, the proposed method can reduce the peak deviation of nodes by at least 7.7%. The experimental results validate that the proposed method can realize the accurate sharing of active and reactive power in finite time, and the dynamic response speed of the system is significantly improved, with good robustness.