1
Ronald B Bailey, Thomas D Stitt, Dennis F Williamson: Control logic for a phase controlled rectifier system. General Electric Company, J H Beusse, May 1, 1979: US04152758 (32 worldwide citation)

Apparatus for providing firing signals to a phase controlled rectifier circuit at a time at which valves in the rectifier circuit are forward biased without the need for providing continuous firing signals. The apparatus monitors the voltage applied across the rectifier valves and provides a signal ...


2
Charles E Cooper, Thomas D Stitt: Electric power system for starting a large rotatable synchronous machine. General Electric Company, Albert S Richardson Jr, October 7, 1986: US04616166 (30 worldwide citation)

For starting a rotatable 3-phase a-c electrical machine of the synchronous type, the stator windings of the machine are connected to an electric storage battery via a controllable electric power converter, and the d-c field winding is connected in series with the stator windings by inserting it in t ...


3
Ronald B Bailey, Thomas D Stitt: Chopper type propulsion system with low speed electrical braking capability for traction vehicles. General Electric Company, Albert S Richardson Jr, August 18, 1981: US04284936 (29 worldwide citation)

A propulsion system for an electrically driven traction vehicle includes a chopper, a d-c traction motor, and means effective when the system is operating in a motoring mode for connecting the chopper in series with the armature and the field windings of the motor to a d-c electric power source that ...


4
Herbert J Brown, Thomas D Stitt: Speed reducing control system for a polyphase electric motor. General Electric Company, Albert S Richardson Jr, December 13, 1988: US04791341 (23 worldwide citation)

A variable speed 3-phase a-c motor is connected to a 3-phase source of alternating voltage via a plurality of controllable solid state electric valves which are so arranged and controlled that motor speed can be reduced by skipping selected cycles of the source voltage. For half speed operation 12 v ...


5
Herbert J Brown, Thomas D Stitt: Speed reducing control system with voltage regulation for a polyphase electric motor. General Electric Company, Albert S Richardson Jr, June 18, 1985: US04524316 (19 worldwide citation)

A variable speed 3-phase a-c motor is connected via a plurality of controllable bidirectional switches to a 3-phase source of alternating voltage having a variable fundamental frequency (f) and an rms magnitude (v) that varies with f, and the switches are suitably arranged and controlled so that mot ...


6
Thomas D Stitt, Ajith K Kumar: Regenerative braking protection for an electrically-propelled traction vehicle. General Electric Company, R Thomas Payne, February 1, 1994: US05283507 (17 worldwide citation)

An electric propulsion system for a traction vehicle includes a controllable power converter operable in either a propulsion or an electric braking mode in which power is withdrawn from a wayside source or returned to the source, respectively. The wayside source utilizes certain preselected frequenc ...


7
Charles E Cooper, Thomas D Stitt: Third harmonic auxiliary impulse commutation inverter with means for precharging commutation capacitor. General Electric Company, Albert S Richardson Jr, April 29, 1986: US04585982 (17 worldwide citation)

In a 3-phase third harmonic auxiliary impulse commutated electric power inverter the d-c terminals of which are connected, via a circuit having appreciable electrical inductance, to a voltage source comprising a battery, the commutation capacitor is precharged by cyclically manipulting the conductin ...


8
Ajith K Kumar, Thomas D Stitt: Auto self test of AC motor system. General Electric Company, Ann M Kratz, Marvin Snyder, November 8, 1994: US05363039 (15 worldwide citation)

Apparatus and method for auto-self testing of a power converter and motor system wherein the power converter has three parallel legs, each including two series connected gate-turn-off thyristors (GTO) connected between a pair of DC power source buses. A microprocessor controls the test sequence in w ...


9
Ajith K Kumar, Thomas D Stitt: Auto self test of AC motor system. General Electric Company, R Thomas Payne, November 30, 1993: US05266891 (14 worldwide citation)

Apparatus and method for auto-self testing of a power converter and motor system wherein the power converter has three parallel legs, each including two series connected gate-turn-off thyristors (GTO) connected between a pair of DC power source buses. A microprocessor controls the test sequence in w ...


10
Charles E Cooper, Thomas D Stitt: Electric power inverter with adaptive third harmonic auxiliary impulse commutation. General Electric Company, Albert S Richardson Jr, April 29, 1986: US04585983 (14 worldwide citation)

In a 3-phase third harmonic auxiliary impulse commutated electric power inverter, during a commutation interval the firing signal for the oncoming main valve of the inverter is delayed for a programmed interval of fixed duration after the commutation capacitor voltage changes polarity, whereby the p ...