The dynamic voltage restorer (DVR) is efficient in solving the voltage quality problems. In the DVR control system
the inner loop is usually designed to regulate the control object and enhance the damping of the system. However
the inner current loop needs extra sensors. Moreover
it will make the processes of design and debugging more complex. This paper proposes a control strategy without the inner current loop. In the proposed system
a notch filter is employed to improve the damping and the feedforward controller is used to increase the response speed. In addition
a repetitive controller is introduced to improve the steady state performance and the harmonics suppression capacity. The proposed control method is simple to design
easy to achieve and economically feasible for implementations. Simulation and experiment results with a 2.2 kW DVR verify the effectiveness and practicability of the proposed control method.