Enhancement of Wind Energy Conversion Using Axial Flux Generator

Abstract

This paper investigates the application of the axial flux machine (AFM) to the wind energy conversion systems (WECS) to obtain high power and torque at reduced cost. By developing mathematical equations using the phase and active transformations, the three-phase model is transformed to two-phase equations by making both the stator and rotor as reference frames, finally converting to arbitrary reference frame, which is useful for the modelling of the axial flux machine. The torque, current, and voltage equations are expressed to improve the simulation reliability. Based on the developed equations, the mathematical model for the axial flux machine is developed using the MATLAB/Simulink. Starting with the axial flux motor model, when the load on the motor increases, how the parameters like torque, current, and speed of the motor vary are explored in this paper. Then for the axial flux generator model, when the wind speed exceeds the rated speed how the torque, line voltages, currents, power and speed of the generator behave are investigated and presented in this paper. The developed model in this paper could be extended to a twin-rotor axial flux synchronous machine, which will lead to the development of more efficient WECS.Conversion System (WECS) plays a prominent role. WECS is the only renewable energy resource which can be placed and developed around the globe due to its main advantage of using the wind energy for the generation of power [1] which is abundant in many parts of the world. From the starting stages of WECS to the present developed technology, many types of generators are used for the power production and every generator is replaced by the other due to the disadvantages that are shown by the generators after using them for a quite long time and problems that are showcased by the generators cannot be solved and for the solution, the researchers are opting for the other model which is not having the problems that are witnessed with the older one. The present and latest generator model for the conversion process is Axial flux synchronous generator which possess more advantages and less disadvantages when compared to the other generator models that are previously used for the generation of the power from wind energy. For many years, the onshore wind farms are having more grip over the power generation from the wind energy, but these days, the offshore wind farms growth has increased rapidly due to the main advantage of having more wind speed in the middle of the water filled areas and with this more speed, the amount of power generated from the turbine is more because from the turbine and wind speed relation we know that, the mechanical power which is produced from the wind energy is directly proportional to the cube of the wind speed; when there is slight increase in wind speed it results in producing more energy from the turbine. The more the wind energy, the amount of power generated will also be more unless until there is no sudden change in the speed of the wind. In general, the wind speed will be l...