Abstract: A method of conditioning tantalum capacitors on printed wire assemblies is disclosed. According to the method, each of the capacitors on an assembly is subjected to the same conditioning level during testing. To condition the tantalum capacitors, surge currents are induced in the capacitors in a controlled manner as a way of aging the capacitors so that they can be used without de-rating rating with low failure rates. The level of voltage, timing and current levels are set by circuitry used to perform the testing. The same circuits that are used with the capacitors in a system application are also used for the tantalum capacitor test circuit during the conditioning process.

Abstract: A power converting apparatus and method providing for the addition of a fourth power connection wire to the neutral point of the normal three phase load circuit. This allows delivery of combined current from the center of the DC link voltage to load. The added control enables a third harmonic injection to flow and allows for increased power rating per peak amp handled by the conversion system. Limiting of faults to the positive half versus the negative half of the DC system allows for more robust behavior when encountering these fault conditions.

Abstract: A power conversion system includes two three-level converters, and a phase shifted transformer coupled to the converters.

Abstract: A galvanic isolated DC-DC and DC-AC power conversion system is coupled to a plurality of DC sources which are derived from a combination of a plurality of single-phase and three-phase AC-DC converters. The DC-DC and DC-AC power conversion system in one embodiment is configured to provide mixed type outputs (mixed frequency, e.g. DC with 50 or 60 Hz, with 400 Hz; mixed voltage levels).

Abstract: A power conversion system has a three-phase AC input, where each AC input phase is linked to a string of cascaded single-phase AC-DC converters placed in series with a three-phase AC-DC converter. Each single-phase AC-DC converter in one embodiment includes a silicon carbide (SiC) pulse width modulated MOSFET H-bridge that placed in series with the three-phase AC-DC converter that includes a silicon (Si) SCR bridge. The single-phase AC-DC converters and the three-phase AC-DC converter together in one embodiment include a mixed silicon-carbide (SiC) and silicon (Si) device topology.

Abstract: A power system for providing an output power to a load is provided. The system comprises a generator configured to generate an alternating current input power and an power converter system coupled to the generator and configured to generate an output power and provide the output power to the load through at least one transformer. The system further comprises a converter control system coupled to the converter system and configured to drive the converter system in an interleaved pattern to reduce harmonic components in the output power and the alternating current input power.

Abstract: A method of conditioning tantalum capacitors on printed wire assemblies is disclosed. According to the method, each of the capacitors on an assembly is subjected to the same conditioning level during testing. To condition the tantalum capacitors, surge currents are induced in the capacitors in a controlled manner as a means of aging the capacitors so that they can be used without de-rating rating with low failure rates. The level of voltage, timing and current levels are set by circuitry used to perform the testing. The same circuits that are used with the capacitors in a system application are also used for the tantalum capacitor test circuit during the conditioning process.

Abstract: A power converting apparatus and method providing for the addition of a fourth power connection wire to the neutral point of the normal three phase load circuit. This allows delivery of combined current from the center of the DC link voltage to load. The added control enables a third harmonic injection to flow and allows for increased power rating per peak amp handled by the conversion system. Limiting of faults to the positive half versus the negative half of the DC system allows for more robust behavior when encountering these fault conditions.

Abstract: A method to balance transformer flux among a plurality of transformers is disclosed. The plurality of transformers is connected to a plurality of converters, each transformer having an associated converter. The method comprises determining a reference flux value, measuring an actual flux value for each transformer, and developing a plurality of voltage command signals in relation to a plurality of variance values between the reference flux value and each actual flux value. In response to the voltage command signals being received at a modulator in signal communication with the plurality of converters, the method proceeds by generating a plurality of switching signals to reduce each of the variance values by making available the plurality of switching signals to each of the associated plurality of converters.

Abstract: A method to balance transformer flux among a plurality of transformers is disclosed. The plurality of transformers is connected to a plurality of converters, each transformer having an associated converter. The method comprises determining a reference flux value, measuring an actual flux value for each transformer, and developing a plurality of voltage command signals in relation to a plurality of variance values between the reference flux value and each actual flux value. In response to the voltage command signals being received at a modulator in signal communication with the plurality of converters, the method proceeds by generating a plurality of switching signals to reduce each of the variance values by making available the plurality of switching signals to each of the associated plurality of converters.

Abstract: A system and method for power control in wind turbines are provided. The method includes switching a plurality of switching devices in a power conversion component of the wind turbine system in a normal switching mode to provide power flow through the power conversion component. The method further includes switching the plurality of switches devices in the power conversion component of the wind turbine system in a short circuit switching mode to prevent power flow through the power conversion component.

Abstract: An apparatus for cooling electrical protective devices comprises an electrical protective device mounted to at least one electrical terminal, wherein the electrical terminals are cooled to indirectly cool the electrical protective devices. A pressurized coolant source passes a coolant fluid through coolant passages attached to the electrical terminals, thereby cooling the electrical terminals. The cooled electrical terminals maintain the temperature of the electrical protection device within an appropriate operating temperature range. This cooling method may be used to increase the fuse power rating of a fuse array while maintaining electrical coordination between the fuses in the fuse array and electrical devices protected by the fuse array.

Abstract: An apparatus for cooling electrical protective devices comprises an electrical protective device mounted to at least one electrical terminal, wherein the electrical terminals are cooled to indirectly cool the electrical protective devices. A pressurized coolant source passes a coolant fluid through coolant passages attached to the electrical terminals, thereby cooling the electrical terminals. The cooled electrical terminals maintain the temperature of the electrical protection device within an appropriate operating temperature range. This cooling method may be used to increase the fuse power rating of a fuse array while maintaining electrical coordination between the fuses in the fuse array and electrical devices protected by the fuse array.

Abstract: The present invention enables removal of unwanted shaft currents from motors and/or generators by effectively placing a seal or a bushing in contact with the motor housing and the motor shaft. Many existing motor units can be effectively retrofitted to include these efficient current discharge mechanisms.