Magnetic Continuously Variable Transmission for Reduction of Wind Turbine Drivetrain Size

The objective of this research is to do analysis on magnetic gears for the application of Magnetic Continuously Variable Transmissions (mCVTs) on wind turbines. Wind turbines convert the kinetic energy of wind into electrical energy. A primary component of the wind turbine is the gearbox. Currently, mechanical gears are used in the gearbox; however, there are several issues with the physical contact required to transfer power between the shafts, such as wear-and-tear, heat, and misalignment. Magnetic gears are a potential solution to many of these problems as they function without contact and are not as severely impacted by misalignment. Bidirectional conversion for the control rotor, harnessing wind at all possible wind speeds, and increasing speed while holding torque, are all desirable features of an mCVT for wind turbines; however, they each require a larger and more expensive power electronics converter in the drivetrain. A two-axis testbed and a magnetic gear prototype is designed to test the impact of misalignment on the operation of the magnetic gear. Solutions to reducing the size and cost of the power electronics considered in this research include: only using unidirectional converters on the control rotor, using optimum gear ratios, considering different synchronous generator speeds, and only harnessing wind above certain wind speeds. Matlab data is collected to compare wind speed to the output power, analyze power generation capacity lost by using only a unidirectional, and review power to gear ratio relationships. The costs and benefits of each solution is considered based on the data collected. The experimental data from the prototype is compared to simulated data on the prototype to compare the evaluate the demonstrator. The data from the prototype is used to form torque angle curves of the magnetic gears at varying misalignments and is evidence that the magnetic gear is a viable replacement for mechanical gears