Power Character Improvement Using Nonlinear Inductance in SWPGS with AMPTC

This paper describes about improvement the power character using nonlinear inductance in SWPGS with AMPTC. Wind power generation system is a one that converts the kinetic energy of the wind into electrical energy. In particular, it is very important to increase the operation efficiency because small wind power systems can be used as an efficient independent power source in areas with large power demand and no other energy sources. The SWPGS with AMPTC consists of a wind turbine, a PM generator, two rectifiers, a battery and a load. The wind turbine is a horizontal axis with three blades and the PM generator has a structure with the reactance bridges and two Y-connected winding sets. This system can automatically track the maximum power from the wind by changing the nonlinear inductance without the need for converters and control circuits. At this time, the variation of the nonlinear inductance follows the saturation characteristic of the reactance bridges in the internal magnetic circuit of the generator. In this paper, using this principle, the problem of fully approaching the maximum power curve of a wind turbine with the power characteristics of a wind power system following the rotational speed change is mathematically modeled. In other words, the output characteristics of SWPGS with AMPTC were close to the concave characteristics as well as the maximum output characteristics of wind turbines. Finally, without control circuit, the load power characteristic curve was allowed to operate at the maximum power point of the wind turbine. We also verified the accuracy of the theory by changing the nonlinear inductance in a stand-alone small-scale wind power system through simulation analysis using MATLAB.