Research On The Potting Material And Technology Of The Electromagnetic Coil Of The High Temperature Magnetic Levitation Bearing Stator

The high temperature magnetic bearing stator coil packaging technology was studied, and the packaging materials and packaging technology was researched initiatively. The reason of short life about the high temperature magnetic bearings stator coil and coil short-circuit failure mechanism have been researched, According to the analysis about material properties, the glass, glass-ceramics, alumina cement, and so on as the packaging material was tried, and the analysis of the performance test was analysed , discussing the material properties of the packaging material, and that provides a theoretical basis for the coil package technology; and the package structure of the magnetic coil and packaging technology program was designed. The results show that, the glass without alkali and the glass-ceramics can be achieved the low–temperature common combine(LTCC), and it has excellent insulation performance at high temperature. But there are some disadvantages, for instance , severe cracking of the surface for sintering contraction; alumina cement has excellent performance at high temperature and thermal shock, but it has the shortcoming of low density; based on analysis and experiments of the packaging materials, an inorganic aluminum phosphate gel which can meet the requirements of packaging materials was prepared. The bonding mechanism of inorganic colloid was researched, and ceramics and glass fiber modification of inorganic colloidal properties was studied.The results show that inorganic colloid can wet the metal matrix, and form a layer at the bonding interface with a transition layer several microns thick; Al₂O₃ceramic mixing can improve the colloidal inorganic after curing at high temperature insulation, mixing glass fibers can improve thermal shock resistance of materials, resistance to cracking and the appearance of the package quality of the coil. The thermal stress of high-temperature magnetic bearing stator coil package was analyzed by using ANSYS finite element software, and the heat stress and strain contours of the coil package was analyzed under different package thickness of the package and different temperature loading to the package body by using APDL language. The methods and measures to reduce thermal stress of the high temperature magnetic bearings coil package on the operating temperature.