Sundstrand Corporation

Hamilton Sundstrand Corporation

Donald G Fair

John J Dhyanchand

Chai-Nam Ng

P R Chetty

Pandipati R Chetty

A generator/starter system for starting an engine and for tapping power from the engine in order to generate electricity includes a squirrel cage rotor, a main stator winding, an auxiliary stator winding, and an excitation source. The main stator winding is magnetically coupled to the squirrel cage rotor so as to provide an AC output in response to rotation of the squirrel cage rotor and so as to rotate the squirrel cage rotor in response to an AC input. The auxiliary stator winding is magnetically coupled to the squirrel cage rotor so as to provide excitation current when the main stator winding is providing the AC output. The source of excitation current is coupled to the auxiliary stator winding.

Induction motor/generator system

An electrical apparatus, comprises a bridge circuit having a plurality of rectifier legs electrically coupled in parallel. Each of the rectifier legs comprises a first and a second rectifier coupled in series and having an input node therebetween. The electrical apparatus further comprises a switch, having a control input, a power input, and a power output, coupled in parallel with the bridge circuit, and a controller having a control output coupled to the control input of the switch for regulating the opening and closing of the switch. When the bridge/switch element is coupled to the disassociated neutral terminals of a wye wound electrical device, the controller modulates the opening and closing of the switch to provide an current controlled soft start of the device, as well as continued motor drive capability, including acceleration and breaking of the device. When the element is coupled to the disassociated neutral of a multi-phase generator or transformer, the controller modulates the opening and closing of the switch to provide output power regulation. This regulation allows controlled battery utilization and charging in one embodiment.

One switch multi-phase modulator

A soft-start control for use with a push-pull converter-regulator having a flux balancing circuit. The push-pull converter is responsive to a pulse width modulated waveform to provide a DC output, the converter having an error amplifier for comparing the DC output to a reference signal to vary the duty cycle of the pulse width modulated waveform. The soft-start circuit provides a varying reference signal to the error amplifier, the reference signal gradually increasing from zero to a predetermined level during the start-up of the converter.

Soft-start control for a push-pull converter-regulator with a flux

A direct current to alternating current inverter with an output transformer is regulated by a pulse width modulator which alternately closes one of two switches connected with the center tapped primary winding of the output transformer. A synchronizing circuit for the pulse width modulator has means for gating synchronizing pulses to the clock of the modulator, blocking synchronizing signals which would cause an unbalance in the duty cycles of the switches and saturation of the output transformer.

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Belvidere, IL, United States of America

Donald G Fair