Abstract: An electrical system for connecting a wind turbine to a power grid that includes: a frequency converter that converts electric power produced by a generator of the wind turbine into electric power that is synchronized with the electric power of the power grid; a transformer that steps up the voltage for connection to the power grid, the transformer being disposed between the frequency converter and a connection to the power grid; and a grid-side crowbar circuit; wherein the grid-side crowbar circuit is configured to apply a short circuit to the electrical system upon the detection of a fault.

Abstract: An electrical system for connecting a wind turbine to a power grid that includes: a frequency converter that converts electric power produced by a generator of the wind turbine into electric power that is synchronized with the electric power of the power grid; a transformer that steps up the voltage for connection to the power grid, the transformer being disposed between the frequency converter and a connection to the power grid; and a grid-side crowbar circuit; wherein the grid-side crowbar circuit is configured to apply a short circuit to the electrical system upon the detection of a fault.

Abstract: An integrated fault and personnel protection system and method for a multi-thread converter in a wind turbine power system is provided. The structure and method provide for system optimization, as well as, arc flash protection. Fault sensing with means of removing power applied to the converter minimizes the energy available to produce an arc flash event. Sensing and disconnects devices for the protections are provided close to the source of energy to protect more of the system. Converter controls detect, identify and isolate faults selecting the best combinations of the novel specific fault isolation devices. Components are distributed into separate physical to enhance protection.

Abstract: A system and method are provided to isolate outputs of parallel converter threads of a power system converter of a wind turbine generator by utilizing isolated power windings on the output transformer from the converter. Such isolation eliminates the circulating common mode current between the parallel converters of the wind turbine system and eliminates the need for a common mode inductor. System reliability is enhanced and total system cost is reduced.

Abstract: An apparatus for rapidly tracking fundamental frequency information in the signal of an electric grid is a cross-coupled phase-lock loop filter (CCPLL) that includes the use of a phase-lock-loop (PLL) apparatus having a plurality individual filters, wherein an input for a first filter in the plurality of individual filters comprises the signal of the electric grid and an output signal from at least a second filter in the plurality of individual filters. A method for using the CCPLL includes applying a signal to the CCPLL and monitoring the output of the CCPLL. Use of the CCPLL may be accomplished or modeled via computer instructions stored on machine readable media.

Abstract: A system and method are provided to isolate outputs of parallel converter threads of a power system converter on a generator side of a wind turbine generator by utilizing isolated power windings on the wind turbine generator. Such isolation eliminates the circulating common mode current between the parallel converters of the wind turbine system and eliminates the need for a common mode inductor. System reliability is enhanced and total system cost is reduced.

Abstract: A system and method are provided to isolate outputs of parallel converter threads of a power system converter on a generator side of a wind turbine generator by utilizing isolated power windings on the wind turbine generator. Such isolation eliminates the circulating common mode current between the parallel converters of the wind turbine system and eliminates the need for a common mode inductor. System reliability is enhanced and total system cost is reduced.

Abstract: An integrated fault and personnel protection system and method for a multi-thread converter in a wind turbine power system is provided. The structure and method provide for system optimization, as well as, arc flash protection. Fault sensing with means of removing power applied to the converter minimizes the energy available to produce an arc flash event. Sensing and disconnects devices for the protections are provided close to the source of energy to protect more of the system. Converter controls detect, identify and isolate faults selecting the best combinations of the novel specific fault isolation devices. Components are distributed into separate physical to enhance protection.

Abstract: A system and method are provided to isolate outputs of parallel converter threads of a power system converter of a wind turbine generator by utilizing isolated power windings on the output transformer from the converter. Such isolation eliminates the circulating common mode current between the parallel converters of the wind turbine system and eliminates the need for a common mode inductor. System reliability is enhanced and total system cost is reduced.

Abstract: A power converter for coupling an electrical machine to an electrical grid includes a machine side converter and a grid side converter, each, side having a plurality of corresponding stages for converting a three-phase electrical signal of the electrical machine to a three-phase electrical signal of the electrical grid. The machine side converter includes a plurality of single-phase bridges coupled in series. The grid side converter includes a plurality of three-phase bridges. Each three-phase bridge corresponds to one of the single-phase bridges of the machine side converter. Each three-phase bridge is coupled to the primary windings of a corresponding transformer. The secondary windings of each corresponding transformer is phase-shifted from its primary windings and is coupled to secondary windings of another respective transformer, thus providing for coupling of the three-phase bridges in a series.

Abstract: An apparatus for rapidly tracking fundamental frequency information in the signal of an electric grid is a cross-coupled phase-lock loop filter (CCPLL) that includes the use of a phase-lock-loop (PLL) apparatus having a plurality individual filters, wherein an input for a first filter in the plurality of individual filters comprises the signal of the electric grid and an output signal from at least a second filter in the plurality of individual filters. A method for using the CCPLL includes applying a signal to the CCPLL and monitoring the output of the CCPLL. Use of the CCPLL may be accomplished or modeled via computer instructions stored on machine readable media.

Abstract: An apparatus for rapidly tracking fundamental frequency information in the signal of an electric grid is a cross-coupled phase-lock loop filter (CCPLL) that includes the use of a phase-lock-loop (PLL) apparatus having a plurality individual filters, wherein an input for a first filter in the plurality of individual filters comprises the signal of the electric grid and an output signal from at least a second filter in the plurality of individual filters. A method for using the CCPLL includes applying a signal to the CCPLL and monitoring the output of the CCPLL. Use of the CCPLL may be accomplished or modeled via computer instructions stored on machine readable media.

Abstract: Method and apparatus that provide a response to the negative sequence current demands during a disturbance of the grid system connected to power-generating equipment, such as a wind turbine system, provide for tracking components in the grid signal, orienting at least a portion of the signal, and injecting the oriented portion. Controlled injection of negative sequence current provides for extending small-signal control response, and also provides for modifications of the apparent impedance to the grid interconnect of the power conversion equipment.

Abstract: A power converter for coupling an electrical machine to an electrical grid, the power converter including a machine side converter and a grid side converter, each side having a plurality of corresponding stages for converting a three-phase electrical signal of the electrical machine to a three-phase electrical signal of the electrical grid; wherein the machine side converter includes a plurality of single-phase bridges coupled in a series and has at least one coupling for coupling with the electrical machine; wherein the grid side converter includes a plurality of three-phase bridges, each three-phase bridge corresponding to one of the single-phase bridges of the machine side converter; wherein each three-phase bridge is coupled to the primary windings of a respective transformer while the secondary windings of the respective transformer are phase-shifted from the primary windings thereof and are coupled to secondary windings of another respective transformer, thus providing for coupling of the plurality of t

Abstract: The invention provides a heat sink assembly, and a method of making and using a heat sink assembly, for cooling a device using circulating fluid. The heat sink assembly comprises a housing including at least one housing inlet passage and at least one housing outlet passage. A first cavity is disposed in the housing and a plurality of first cavity column members are disposed in the first cavity. The first cavity column members are arranged in a plurality of rows such that first cavity column members in a row are staggered with respect to first cavity column members in an adjacent row. The heat sink assembly further includes a second cavity disposed in the housing and a plurality of second cavity column members disposed in the second cavity. The second cavity column members are arranged in a plurality of rows, which are also staggered.

Abstract: A method is provided for determining a shorted thyristor cell in a bridge that supplies a load from a source, the bridge including a plurality of the thyristor cells. The method includes the step of sequentially gating each of the cells to a conducting state, so that only one cell is gated at one time; providing at least one current transformer in the bridge; generating a current flow that passes through the bridge including the one cell that is gated; observing current in the at least one current transformer to determine a short in one of the cells the that is not gated; and determining a shorted cell based on the step of observing current in the at least one current transformer.

Abstract: The invention provides a heat sink assembly, and a method of making and using a heat sink assembly, for cooling a device using circulating fluid. The heat sink assembly comprises a housing including at least one housing inlet passage and at least one housing outlet passage. A first cavity is disposed in the housing and a plurality of first cavity column members are disposed in the first cavity. The first cavity column members are arranged in a plurality of rows such that first cavity column members in a row are staggered with respect to first cavity column members in an adjacent row. The heat sink assembly further includes a second cavity disposed in the housing and a plurality of second cavity column members disposed in the second cavity. The second cavity column members are arranged in a plurality of rows, which are also staggered.

Abstract: A method is provided for determining a shorted thyristor cell in a bridge that supplies a load from a source, the bridge including a plurality of the thyristor cells. The method includes the step of sequentially gating each of the cells to a conducting state, so that only one cell is gated at one time; providing at least one current transformer in the bridge; generating a current flow that passes through the bridge including the one cell that is gated; observing current in the at least one current transformer to determine a short in one of the cells the that is not gated; and determining a shorted cell based on the step of observing current in the at least one current transformer.

Abstract: An active power line compensation circuit for providing a power distribution network with a series compensation system that utilizes a transformer-coupled three-phase voltage-source inverter. A solid-state thyristor shorting ("crowbar") switch is provided on a third winding of a coupling series transformer. The transformer couples the ac output of a three-phase voltage-source inverter (VSI) to the power distribution network. The crowbar switch circuitry utilizes three diode-thyristor pairs, where each pair is connected to one phase leg of the VSI. The thyristors of the crowbar switch are each controlled by an fault output signal from an overcurrent or overvoltage sensor, that is coupled to a tertiary winding of the transformer. The fault signal closes the thyristors and thereby shunts overcurrent that would otherwise flow through the VSI. When the fault signal ceases, the thyristors automatically switch open when a null current is present in the normal three-phase line current.

Abstract: An active power line conditioner circuit having a series compensation system arrangement utilizes a transformer-coupled three-phase voltage-source inverter. A conventional metal oxide varistor (MOV) and bypass breaker combination are provided on the line side of the coupling transformer. A solid-state thyristor shorting ("crowbar") switch is provided on the secondary side of the coupling transformer across the outputs of the three-phase voltage-source inverter (VSI). The crowbar switch circuitry utilizes a diode bridge with a thyristor on the dc side of the bridge resulting in the simplification that only one active device need be gated. Crowbar switching logic activates the crowbar switch based on the exceeding of a threshold voltage measured at the dc power source link to the voltage-source inverter. A direct measure of dc source link voltage is employed to determine when to trigger the conduction of the crowbar thyristor switch.