Trends bearingless motor
No bearing motors, the origin and development
Ferrari and Tesla's polyphase alternating current system of the invention, after the mid - 1880 - s, more Voronezh WoErSiJi invented the three-phase asynchronous motors, induction motors without brush and commutator, but long-term high-speed operation, the bearing is difficult to maintain .
After World War II, Buy SKF 6202 Bearing Online the development of the DC magnetic bearing to contact the motor and drive systems can run, but the cost is very high http://www.bearing-sa.com/product/SKF-6202-Bearing-152748.html, because the transmission system is not ferromagnetic objects in a constant magnetic field in a stable suspension. Active magnetic bearings invention to solve the problems, but active magnetic bearing support over five degrees of freedom is applied magnetic bearing bulky, complex structure, high cost of controlling rigid rotor.
20 th century, in order to meet the development and utilization of nuclear energy, the need to use high-speed production of enriched uranium centrifuge, magnetic bearings can support high-speed motor to meet the requirements, then start research programs in Europe in magnetic bearings. 1975, Herman bearingless motor patent applications, patent proposes a logarithmic relationship between the coil and the magnetic bearing of Canada or minus a number of windings. The solution proposed by Herman, at the time it is impossible to make no bearing motor.
Further progress in magnetic materials with magnetic properties, laying a permanent magnet synchronous motor with a strong competitive position. At the same time, with the application of bipolar transistors, and Berlin, and made a condition of the switching circuit, to meet the requirements of bearingless motor can produce a new generation of high-performance power amplifier. Around 1985, with rapid and load capacity of the power switching devices, and has more than 20 years with AC motor vector control technology for digital signal processors appear in practical applications, so difficult without bearing motor digital control to solve. Technology on the basis of the Swiss Federal Institute of Technology Zurich Kerby scientific and technological progress on in the last century in the 1980s is no bearing motor first produced.