Abstract: A semi-conductor system for controlling three phase motors by voltage and/or frequency variations. An input circuit provides dc power, such as a three phase full wave input bridge with silicon control rectifiers to provide a voltage controlled dc power output. An output inverter bridge having six silicon rectifiers receives dc power and converts it to three phase ac power for operating an induction motor. A diverter network is connected between the dc power input circuit and the output inverter and is activated periodically for temporarily diverting the dc power from the inverter in order that the inverter rectifiers may be turned off. The diverter may include a tank circuit having a capacitor and an inductor connected across the dc power output through a diode and a silicon control rectifier is connected to the tank circuit for shunting the dc power from the inverter and applying a reverse voltage to the inverter.

Abstract: A vehicle propulsion system combines an electric motor-generator and battery with a flywheel as regenerative power sources. A planetary differential gear train couples together the shafts from the flywheel and the motor-generator. A controller connected between the battery and the motor-generator serves to maintain the current level to or from the battery with a range which develops optimum efficiency of battery energy utilization while causing the flywheel to absorb the relatively large peaks in battery power requirements.In one embodiment, the controller is made up of a transistorized chopper, a free-wheeling diode, a regenerative diode, a current sensor, and a switch to change the controller between the motor and generator modes of operation. The motor-generator is a separately excited, DC machine.

Abstract: A pulse width modulated three-phase inverter has notches in the output waveforms to control the harmonic content thereof.

Abstract: A thyristor commutation circuit simultaneously commutates all of the conducting thyristors for a plurality of loads with a single commutating capacitor. Load control circuits for direct current powered loads and both single-phase and multi-phase alternating current powered loads, all with different current requirements, may be commutated at the same time.

Abstract: A circuit for a thyristor line controller interconnecting an alternating current voltage generating power source to a load that controls the amount of power delivered to the load and reduces the fundamental frequency component to f/n, where f is the frequency of generated voltage, and n is an integral number.