Maximum Power Point Tracking Strategy for a New Wind Power System and Its Design Details

Abstract

This study presents two methods to improve the maximum power point tracking(MPPT) strategy for a new wind power system that consists of a planetary gear, two permanent magnet synchronous machines, and loads. The generator, the electric motor, and the wind turbine are connected to the sun gear, ring gear, and carrier of planetary gear, respectively. With the aid of an electric motor, the system can track the maximum power without the full-power converter for generator because of its special operating principle. Conventional optimum torque (COT) control method with a torque error feed forward branch is proposed to obtain faster response compared with COT control method. Moreover, considering that the actual power cannot reach the theoretical optimum point due to the loss torque of the system, the COT control with torque loss compensation is described. A method is also proposed to estimate loss torque.

Existing System

Optimum Control Technique.

Proposed System

This study has developed a MPPT torque control method for a new wind power system and has mainly focused on improving this method to enhance ability in capturing wind energy. By adjusting the feed-forward coefficient to obtain rapid response, the system can track well the variation of wind velocity. However, it actually produces power fluctuations. Moreover, the research results indicate that the behavior of loss torque compensation really helps to make the operating point close to the optimum value. Thus, the energy production can be increased with the help of this study.

Architecture

MPPT control scheme with torque error feed forward branch