Abstract: A DC Link for use with a multi-phase DC to AC converter provides soft-switch opportunities to the main inverter devices only when such opportunities are required. A quasi-resonant rail swings from source to ground potential either with or without the assistance of an auxiliary switch. The quasi-resonant rail swings from ground to source potential with the assistance of an auxiliary switch. Low switch stresses are characteristic in both the main inverter switch devices and the DC link switch devices. Main power is carried predominantly through a DC link switch thereby minimizing power handling requirements of DC link reactive components.

Abstract: A DC Link for use with a multi-phase DC to AC converter provides soft-switch opportunities to the main inverter devices only when such opportunities are required. A quasi-resonant rail swings from source to ground potential either with or without the assistance of an auxiliary switch. The quasi-resonant rail swings from ground to source potential with the assistance of an auxiliary switch. Low switch stresses are characteristic in both the main inverter switch devices and the DC link switch devices. Main power is carried predominantly through a DC link switch thereby minimizing power handling requirements of DC link reactive components.

Abstract: An electric motive power unit including a multiple phase AC electric machine and heat dissipative electronic components therefor, the improvement wherein the machine is disposed in a thermally conductive housing having cooling fluid passages formed therein, and the heat dissipative electronic components are individually mounted on an exterior periphery of said housing and distributed in a fashion wherein circulation of the fluid through said fluid passages for the cooling of said machine also serves to cool said heat dissipative electronic components.

Abstract: An AC to DC power converter comprises an imput filter for filtering the alternating current input and an output filter for filtering and smoothing the direct current power output to a load. The output alternating current of the input filter is rectified and electronically switched by buck and boost switching circuits at a frequency much higher than the frequency of the alternating line current input. The rectified line current is sensed and provided to a control circuit which controls the operation of the buck and boost switching such that the power line current will follow a predetermined reference voltage waveform.

Abstract: An AC to DC power converter comprises an input filter for filtering the alternating current input and an output filter for filtering and smoothing the direct current power output to a load. The output alternating current of the input filter is rectified and electronically switched by buck and boost switching circuits at a frequency much higher than the frequency of the alternating line current input. The rectified line current is sensed and provided to a control circuit which controls the operation of the buck and boost switching such that the power line current will follow a predetermined reference voltage waveform.