Abstract: An improved power semiconductor heat dissipation apparatus for regulating the temperature of multiple power semiconductors featuring increased structural integrity for high pressure applications, a more robust heat exchange fin design to accommodate particulates or other solid contaminants that may be present in less refined coolant fluids, and a modified construction for increased durability and ease of automated assembly.

Abstract: An improved, liquid cooled, power semiconductor heat dissipation apparatus configured to accommodate surface-mount power semiconductor devices mounted on direct bond copper plates which are in thermal communication with a heat transfer surface and electrical communication with a printed circuit board or other surface on which the apparatus is mounted.

Abstract: An electric drive motor with an improved liquid cooling system featuring a hollow rotor shaft configured to allow liquid coolant to flow in and out of the rotor shaft through an aperture in one distal end following a path influenced by a coolant tube such that the liquid coolant is directed to flow past a plurality of internally located heat dissipation fins which are in thermal communication with the rotor shaft thereby increasing the heat dissipation, performance, and power density.

Abstract: A packaging and cooling apparatus for power semiconductor devices comprising a printed circuit board and a semiconductor module. The semiconductor module having a manifold element and a semiconductor element consisting of power semiconductor devices, thermally conductive plates, and serpentine fin elements. The power semiconductor devices and serpentine fin elements are bonded to the thermally conductive plates on opposing sides to form plate assemblies. The plate assemblies are installed in the windows of the manifold element forming the semiconductor module, which allows for heat removal from each of the power semiconductor devices. The terminals of the semiconductor module are received in the holes of the circuit board, and soldered to traces. The packaging and cooling apparatus may be potted with a resin to prevent leakage of coolant or sealing may be achieved by use of clamped o-rings.

Abstract: A liquid-cooled, radial air gap electric motor includes a stator, a rotor, a rotor shaft, two end bells, a housing, a coolant manifold system, and a coolant sump. The rotor includes a plurality of axially directed slots located near its periphery. The coolant manifold system directs a first portion of liquid coolant to flow past some portion of the stator and a second portion of liquid coolant to flow through the rotor slots. Some or all of the liquid coolant is received by the coolant sump from which the coolant may be recirculated.

Abstract: A liquid-cooled, radial air gap electric motor includes a stator, a rotor, a rotor shaft, two end bells, a housing, a coolant manifold system, and a coolant sump. The rotor includes a plurality of axially directed slots located near its periphery. The coolant manifold system directs a first portion of liquid coolant to flow past some portion of the stator and a second portion of liquid coolant to flow through the rotor slots. Some or all of the liquid coolant is received by the coolant sump from which the coolant may be recirculated.

Abstract: A liquid-cooled, radial air gap electric motor includes a stator, a rotor, a rotor shaft, two end bells, a housing, a coolant manifold system, and a coolant sump. The rotor includes a plurality of axially directed slots located near its periphery. The coolant manifold system directs a first portion of liquid coolant to flow past some portion of the stator and a second portion of liquid coolant to flow through the rotor slots. Some or all of the liquid coolant is received by the coolant sump from which the coolant may be recirculated.

Abstract: A method of fabricating rotors for induction motors. In a first aspect, arcuately spaced apart rotor bars pass through channels the magnetic core of the motor. The rotors are formed of an elongate portion having a constant cross section parallel to the magnetic core laminations and include two portions protruding beyond the end laminations at opposite ends of the magnetic core. The protruding portions are, at one end, a head much like the head of a "T", and at the other end, a straight continuation of the elongate portion. The rotor bars are formed to fit closely with one another in an interleaving arrangement. The protruding portions form an end ring assembly which is subjected to a consolidation process. In this way, for a rotor having N rotor bars, there will only be N braze joints in each end ring.

Abstract: The present invention pertains to an improved rotor bar design and method of fabrication of asynchronous motors using such rotor bars. The rotor bar design employs "T"-shaped rotor bars that are interleaved around a magnetic core forming a rotor having a minimum amount of bonding interfaces between the rotor bars and end ring portions. The "T"-shaped rotor bars may either be formed from a single piece or from multiple pieces of copper. The single piece rotor bar method provides N bonding interfaces per end ring, where N is the number of rotor bars used. Where the "T"-shaped rotor bars are formed from three pieces for a rotor having N rotor bars, there will be 2N bonding interfaces for each end ring. Also, the "T" shape of the rotor bars may be added after straight rotor bars have been installed in the rotor bar channels in the magnetic core with their end portions extending beyond the rotor bar channels.

Abstract: A DC-to-AC power converter for use with a three phase motor that allows the motor to continue to operate at reduced power in the event of a switch failure in the converter. This is accomplished by using parallel power semiconductor switch poles for each phase. The motor may be wound with parallel windings for each phase to aid current sharing of the parallel poles. This feature is not absolutely required, but the impedance of the windings help balance the currents in the parallel poles. The arrangement of parallel switch poles allows for continued operation of the motor at half of its rated power level in the event of a failure of one of the power switches. Switching frequency and duty cycle of the parallel poles are controlled by a single pulse width modulation signal which is connected to the two drive circuits that control the switches. Fuses, or other circuit disconnect devices are added between the power switch pole outputs and their respective windings of the motor to isolate a failed power switch.

Abstract: A DC-to-AC power converter that is used to drive a three-phase motor while providing for fail soft and emergency operation. The power converter employs a conventional three half-bridge arrangement of power poles and adds a fourth pole to provide for an emergency operation in the event of failure of one of the three normal poles. The fourth (emergency operation) pole is coupled between a pulse width modulated controller and the neutral wire of the motor and is powered by first and second DC power busses. The controller is configured to disable a failed one of the three normal poles, and to control the fourth pole subsequent to disabling of the failed pole. Fuses or other disconnect devices are also added between the three normal poles and the respective windings of the motor. The present power converter allows continued motor operation at a reduced power level in the event of a failure of one of the power poles.

Abstract: A separable inductive coupler for transferring electrical power across a dielectric medium using magnetic induction. Its coil geometry allows for easy disassembly of primary and secondary circuits. When primary and secondary coils are mated, an extremely low leakage inductance transformer is formed. This provides for good high frequency operation at high power density. The coupler allows electrical power transfer without metal-to-metal contact. The design allows easy removal of the primary or secondary coil from the transformer. The coil geometry has very low leakage inductance and very low high-frequency resistance which allows high frequency operation. The power transfer density is much higher than previously achieved with separable inductive couplers. Approximately 6000 watts has been transferred through a version of the present separable inductive coupler having a volume of 25.8 cubic inches, yielding a power density of 230 Watts/cubic inch.