Investment costs and the inconsistency of wind are two major factors that have held back the utilization of wind power generation. With newer, larger models of wind turbines, wind power generation is becoming more cost effective and reliable due to the direct relationship between power capacity and rotor size. For any size wind turbine, however, there are ways to increase the efficiency of power generation. One way efficiency can be increased is with pitch control, which is the ability of wind turbines to adjust the angle of their blades. Another way is to control the load of the generator by using pulse width modulation (PWM) in the AC to DC rectifier, altering the duty ratio.
My capstone design was to construct a horizontal wind turbine that could analyze multi-physics space power flow and select an operating envelope that maximizes power generation. Specifically, the goal was to extract mechanical power from wind, convert it to 3-phase AC power using a synchronous generator, and then rectify the AC power to DC power using a rectifier to obtain a DC voltage and current output. Additionally, power and frequency measurements from the rectifier are utilized within a maximum power point tracking (MPPT) program, written in MatLab, to determine whether pitch angle and duty ratio should be increased or decreased.
From this capstone project, I have (1) successfully designed and manufactured a horizontal axis wind turbine, (2) established a communication link between stationary and rotary subsystems, (3) built and tested individual blade pitch control, and (4) experimentally established a relationship between captured mechanical power and pitch angle.