CONTROL OF A BRUSHLESS PERMANENT MAGNET MACHINE USING AN INTEGRATED TORQUE SENSOR IN PLACE OF A ROTOR POSITION SENSOR

摘要: The work presented in this thesis proposes the use of measured torque feedback from an integrated, low cost surface acoustic wave (SAW) transducer place a position sensor to control brushless permanent magnet (BLPM) machines. BLPM machine closed loop requires knowledge rotor stator current and maximum per ampere. electrical phase or sensorless technique.Position sensors such as absolute encoder resolver are needed for information, encoder, accurately patterned disk rotates between light source detector giving unique digital output signal every shaft position. However, each bit world represents independent track on disk, resulting complex costly sensors. Brushless resolvers operation is based inductive coupling winding. with its converter also gives precise but again often prohibitive. So disadvantages added size machine. techniques obtaining terminal voltages currents estimating back electro-magnetic force (EMF), flux-linkage inductance which can be estimated. back-EMF (1) that they behave poorly at zero speed (2) load disturbances since estimated parameters change. speed, however mounted there no saliency so any variation winding inductances arises magnetic saturation; dominates rate-of-change current; (3) incremental undergoes two cycles single cycle pm causing ambiguity sensed position; (4) distortion due nonlinearities inverter; (5) offsets noise caused by injection.This develops start-up routine algorithms enhance performance machines all speeds, including loads using low-cost, SAW sensor.