Evaluation of magnetic gear parameters for autonomous wind installation with changing wind speed

Abstract

Purpose. To evaluate the parameters and characteristics of the magnetic gearbox at constant and variable wind speed as part of an autonomous wind power plant. Methodology. Analysis of existing methods of mathematical modeling of magnetic gearboxes. Numerical methods of mathematical modeling based on finite elements. Numerical methods of processing the obtained results. Findings. A two-dimensional field mathematical model has been developed to estimate the parameters and characteristics of the magnetic gearbox at variable and constant wind speed. With the help of the developed model, the electromagnetic field, parameters and characteristics of the magnetic gearbox were analyzed both at a constant and at a variable speed of rotation. In particular, it was found that the magnetic system of the reducer does not reach saturation, while the average values of magnetic induction in the structural elements of the reducer remain within the permissible values for the used materials and grades of steel. The obtained data on the average values of the electromagnetic moments of the outer (high-speed) rotor and the inner rotor make it possible to understand the relationship between them and their influence on the operation of the system. A conclusion was made about the uneven distribution of induction along the middle line in the air gap, which is caused by the presence of a modulator in the design of the reducer. In addition, according to the obtained results, the change in wind speed affects the speed of rotation of the magnetic gearbox and the magnitude of the electromagnetic moments of the high-speed and low-speed rotors. Such information helps to understand the dynamics of system operation under different environmental conditions. The results obtained in the study are important for further improvement of the magnetic reducer design and ensuring more efficient operation of the low-power wind turbine. They can be used to optimize the structure and increase its productivity, which will contribute to the development of wind energy and the green energy industry in general. The average value of the electromagnetic moment of the outer (high-speed) rotor is about 7.4 N∙m, while for the inner rotor the value of the electromagnetic moment is about 66 N∙m. The ratio of the moments of the outer and inner rotors is 8.92, which correlates with the reduction factor of the gear under study. Originality.  A two-dimensional field mathematical model has been developed, which takes into account the change in the parameters and characteristics of the magnetic gearbox when the wind speed changes and the random rotation speed of the wind generator rotor. Practical value.  The results of the research of the magnetic reducer for a low-power wind turbine have an important contribution to the development of wind energy, contribute to increasing the efficiency and reliability of energy production, and contribute to the creation of a more sustainable and environmentally friendly energy complex.