Abstract: Angular position and rotation rate of a function generator having stator windings and rotor windings are determined by first amplitude modulating a carrier oscillation to form a sine signal and a cosine signal and then feeding the sine signal and cosine signals to opposite stator windings and thereby inducing in the rotor winding an analog function-generator signal. In turn this analog function-generator signal is converted into a digital function-generator signal from which is derived by means of an algorithm a digital rotation-rate signal which is numerically integrated to obtain an angular-position signal. This angular-position signal is itself used to modulate the carrier oscillation.

Abstract: A circuit for protecting a switching transistor connected between a direct-current voltage source and an inductive load has a voltage-limiting element connected between the source and the transistor for switching the transistor when the voltage of the source exceeds a predetermined limit, elements for deriving from the voltage-limiting element a control signal when the source voltage exceeds the predetermined limit, and a variable pulse-width modulator connected to a control input of the transistor and receiving the signal from the means. The modulator decreases pulse width when the source voltage exceeds the limit.

Abstract: A method and circuit for regulating an alternate or three-phase current motor, a pulse inverter with a capacitive direct current intermediate circuit is used through which the motor is supplied with a substantially constant voltage by means of electronic switches and corresponding antiparallel recovery diodes. For this purpose, the reactive motor current is measured for utilization in the feedback control system. To this end, the feedback current from the motor inductance to the capacitor of the intermediate circuit is measured and the value obtained is used to form a control signal for regulating the reactive current.