Research on power conversion control strategy of ar-ray buoy type wave energy converter

In order to solve the problem of complex inner-loop control structure in the double PI power conversion control method of array buoy type wave energy converter, this article proposed a power conversion control strategy based on the outer-loop PI and inner-loop QPR composite structure that the double closed-loop structure of speed and current was used to realize the control of machine-side rectifier, the three closed-loop structure of the DC bus voltage, the grid current and the capacitor current was used to realize the control of grid-side LCL inverter. Moreover, this article also proposed a graded power generation scheme for single oscillating buoy and double power generation branches, which aimed at solving the problem of small safe working pressure range of accumulator under single buoy and single power generation branch mode. Finally, based on the mathematical model of the main components of the system, the MATLAB/Simulink software was used for modeling and simulation. The results show that the proposed graded power generation scheme and power conversion control strategy can realize the stable operation of the system under three different wave conditions, which verifies the feasibility of the proposed scheme