DMC-based cooperative control strategy for distributed photovoltaic power generation systems

Abstract

In recent years, there have been an increasing number of photovoltaic (PV) generators integrated into the modern distribution power network. However, the introduction of a large number of PV units could have a negative impact on the distributed PV grid-connected power generation systems, such as polluting the grid, and causing grid instability, even resulting in the voltage collapse if the relevant stability and control issues are not properly considered. This paper proposes a two-level control strategy, that is, the upper level is cooperative control and the lower level is dynamic matrix control (DMC). The proposed control strategy not only makes all the distributed PV units converge and operate at the same ratio of the available power, but also regulates the total power output of all the PV units to ensure the stability of the distributed power generation systems. Simulation results on the 4-machine 14-bus distributed power generation test system are provided to verify the validness and effectiveness of the proposed control strategy.