Control circuit for induction motor torque and rotation - has windings supplied directly by operational amplifiers which can be operated in inverting or non-inverting mode

摘要

The induction motor is esp. an eddy current motor with n windings, where n is at least two. Motor windings (33, 34) are directly supplied from power operational amplifiers (21, 24). The amplifier (24) of at least one winding (34) can be switched over from inverting to non-inverting operation. A phase shifter (22) preceeds the inputs of (n-1) amplifiers (24). Amplitude of operational amplifiers' control voltage is adjustable, and the amplifiers can be over driven for braking, so that direct current is applied to motor windings. The control voltage adjustment is carried out by a voltage divider (11, 12, 13) composed of one variable and two fixed resistors.