DC-Bus Voltage Control Technique for Parallel-Integrated Permanent Magnet Wind Generation Systems

This paper presents a dc-bus voltage control technique for a new power conversion topology feasible for parallel-integrated permanent magnet (PM) wind generation systems. This technique is based on a master-slave hysteresis control scheme in order to solve discrepancy problems that could happen between the controllers. A three-phase semicontrolled rectifier topology is proposed here as an effective interface circuit between each wind generator and the dc-bus. The proposed system provides interconnection extension ability of multiwind converter units sharing the same dc-bus and more economic utilization of the wind generator; by ensuring unity power factor operation. More advantages include voltage disturbance compensation capability, robustness: since a short circuit through a leg is not possible and high efficiency: due to the reduced number of switching elements. The rectifier topology concept, the principle of operation, the control scheme, and test results are presented. The developed technique is also implemented on a 12 kW parallel-connected PM laboratory setup in order to confirm the effectiveness of the proposed system.