Deadbeat Decoupling Control of Three-phase Photovoltaic Grid-connected Inverters

The paper proposes a novel deadbeat decoupling control strategy according to the characteristics of three-phase photovoltaic grid-connected inverters. The new deadbeat controller can significantly reduce the ripple and distortion of output currents at the same sampling frequency compared with traditional deadbeat controller without compensation, which will improve the performance of the three-phase photovoltaic grid-connected inverter. It is realized the decoupling control of d-axis current and q-axis current under using grid voltage orientation vector control and deadbeat control for three-phase photovoltaic grid-connected inverters, which makes the active power and the reactive power be independently controlled by d-axis current and q-axis current. The deadbeat controller with compensation has a fast dynamic response ability, which really realizes getting the given value in one step. The simulated and experimental results show that the proposed deadbeat decoupling control strategy provides a high performance solution for three-phase photovoltaic grid-connected inverters, which verifies the feasibility and correctness of the control strategy at same time.