Measuring linear or rotary motion of electric motor - ascertaining rotor or secondary part speed, position, torque or force and deriving transfer model parameters

摘要

The reluctance principle is used to measure the rotor speed or the speed of a linearly moving secondary part, the position of the rotor or part and the torque acting on the electrical drive or the force on the secondary part. The voltage applied to the motor connections and the resulting current are measured against time. A computer, e.g. a microprocessor, continuously computes the effective resistance and inductance for a transfer model contg. only these two elements in series. The values are digitised as measurement signals and stored for later access. Using geometric boundary conditions related to the motor design, the inductance measurement signals are transformed into inductances dependent on pole wheel angle and stored. Using a defined transition time the pole wheel angle is derived and stored. USE/ADVANTAGE - Eliminates some disadvantages of known methods, e.g. no manipulations are required on the supply rectifier. Derived values can be used for regulation, e.g. of rotor r.p.m. or angular position.