Regelung von Tangential- und Radialkräften in bürstenlosen permanentmagneterregten Motoren

Electrical drives for pumps or blowers, which are exposed to abrasive media or which must operate absolutely free of wear and tear are hardly feasible with conventional bearings. As a possible alternative to conventional sliding or roller bearings a bearingless motor may be used. In this paper a control scheme for bearingless motors with permanent magnet excitation is presented. This scheme can help reduce the complexity of the power amplifier substantially. Especially, when the motor is operated in conjunction with a voltage source inverter it is possible to observe the state variables by means of a mathematical model, thus measurement of the phase currents is no longer necessary. Control of the radial rotor position, however, requires a nonlinear controller design.