Abstract: A composite power conversion method using a WYE asymmetrical autotransformer that converts electrical power from AC to DC uses two or more conversion methods in parallel and provides a passive technique that “splits” the input 3-phase voltages into additional phases, so that the number of DC rectification pulses is increased to improve AC line current THD The WYE asymmetric autotransformer topology provides a potential improvement in size/weight and efficiency compared to former asymmetric autotransformers.

Abstract: A composite-like AC-to-DC converter has boosting capabilities. The term “composite AC-to-DC converter” has been coined to distinguish a converter using two or more conversion methods in parallel. All the autotransformer designs for the boost topology composite-like system begin with vector diagrams constructed using the tips of the line-to-line voltage vectors. A constructor arc is swung between these tips equal to the length of the line-to-line voltage vector span. The number of autotransformer three-phase outputs is then determined by the number of equally spaced rays drawn from the opposite vector tip to the arc. The intersection of points of these rays with the arc are used to design the composite-like autotransformer's winding's voltage ratios and interconnections.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Various methods and apparatuses that utilize a wireless time reference system are provided herein. One example method involves calibrating independent, spatially-located clocks of a geoposition system in order to geolocate an object having an associated object tag. The example method may include transmitting an RF pulse pair, receiving the pulse pair at multiple locations, utilizing respective frequencies of first and second spatially-located clocks to produce count values to effect measurement of an interarrival interval at each of multiple locations, determining a ratio of count values relative to said first and second spatially-located clocks, and utilizing said ratio to calibrate time indications of said clocks. Other related methods and apparatus are also provided.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Instead of normalizing time reference of independent spatially-located clocks using a reference tag transmission from known location, the present invention uses an interarrival time interval between a pulse pair of UWB pulses as a timing metric. Thus, a method of synchronizing spatially-located clocks or normalizing time indications thereof comprises transmitting a UWB pulse pair, determining at first and second monitoring stations a respective count value indicative of a locally measured time interval between received pulse pairs, determining a ratio between clock counts of first and second monitoring stations, and utilizing the ratio to determine clock skew, e.g., a timing correction to be applied to respective local clocks of the monitoring stations.

Abstract: Systems and methods are provided for an on-demand boost converter for use in a vehicle. An automotive drive system comprises a boost converter having an input node, a first output node associated with a first boost leg, and a second output node associated with a second boost leg. A fuel cell is coupled to the input node of the boost converter and a battery is coupled to the first output node. An inverter module is coupled to the second output node, and a vehicle traction drive unit is coupled the inverter module. A first switch is coupled between the second output node and the first output node, wherein the battery provides energy to the second output node when the first switch is closed.

Abstract: Systems and/or apparatus are provided for automotive electrical systems having power converters that are coupled by using a transformer. An electrical system comprises a boost converter, wherein a first winding of a transformer is coupled between the input node of the boost converter and a first reference node. The boost converter further includes a switch coupled between the first reference node and a second reference node and a diode coupled between the first reference node and the output node of the boost converter. An energy source is coupled between the input node and the second reference node and a first electrical load is coupled between the output node and the second reference node. The electrical system further comprises a voltage converter having an input coupled to a second winding of the transformer, and a second electrical load coupled to the output of the voltage converter.

Abstract: Systems and methods are provided for discharging a high-voltage bus using semiconductor devices. A discharge system for a first voltage rail and a second voltage rail comprises a first semiconductor device coupled to a first voltage rail and a second semiconductor device coupled between the first semiconductor device and a second voltage rail. A control circuit is coupled to the first semiconductor device and the second semiconductor device. In response to a discharge condition, the control circuit is configured to activate the first semiconductor device and gradually activate the second semiconductor device, such that the energy potential between the first voltage rail and the second voltage rail is gradually dissipated through the semiconductor devices.

Abstract: A vehicular power converter includes switches and first and second inductive components. The first and second inductive components have substantially adjacent portions and are coupled to the plurality of switches such that when current flows from the plurality of switches and through the first and second inductive components, flux generated by the current flowing through the adjacent portions of the first and second inductive components and located between the adjacent portions is oriented in substantially opposite directions.

Abstract: An autotransformer for use in low frequency, high power applications that uses a stack of printed wire boards constructed of a top, inner, and bottom layer including electrical trace windings circumventing the transformer core and formed in the inner layer for direct thermal contact with a heat sink interface providing a uniform and consistent heat path down to the heat sink plate. The autotransformer further includes a board to board connection employing solder cups to electrically connect between predetermined printed wire board traces. The printed wire board autotransformer also may use a non-planar interface for thermal interface with a non-planar heat sink plate surface.

Abstract: A method of operating an isolated bi-directional dc/dc converter to provide voltage regulation at a no-load condition over a wide voltage range and also provide overshoot protection for the boost mode main switching transistors uses new boost mode drive waveforms. The new waveforms drive switches S2 and S4 to be turned off during boost mode and only S1 and S3 are switched to provide reverse energy flow at no-load. In boost mode, C1 and C2 provide overshoot protection caused by leakage inductance of the isolation transformer when boost mode drive transistors turn off during forward energy flow and provide stored energy for reverse energy flow during reverse energy flow periods used for voltage regulation in the boost mode. In buck mode, C1 and C2 provide soft switching for buck mode main switching transistors S2 and S4.

Abstract: A method and apparatus for precharging a DC to DC power converter system is provided. The system includes a boost circuit for generating a boosted output voltage from an input voltage. The input voltage is monitored. A predetermined current limit is compared to a current in the boost circuit, and the current limited is increased when the input voltage is greater than a predetermined value.

Abstract: An ultra wideband (UWB) or short-pulse RF system is disclosed that can be used to precisely locate or track objects (such as personnel, equipment, assets, etc.) in real-time in an arbitrarily large, physically connected or disconnected, multipath and/or noisy environment. A system implementation includes multiple zones or groups of receivers that receives RF signals transmitted by one or more timing reference tags and one or more objects having associated object tags. Each zone or group may share a common receiver. By combining a multiple reference tag system with a virtual group of receivers, i.e., a zoning technique or system, a cost-effective system can be provided that offers scalability and flexibility to monitor a significantly expanded coverage area.

Abstract: Systems and methods are provided for an on-demand boost converter for use in a vehicle. An automotive drive system comprises a boost converter having an input node, a first output node associated with a first boost leg, and a second output node associated with a second boost leg. A fuel cell is coupled to the input node of the boost converter and a battery is coupled to the first output node. An inverter module is coupled to the second output node, and a vehicle traction drive unit is coupled the inverter module. A first switch is coupled between the second output node and the first output node, wherein the battery provides energy to the second output node when the first switch is closed.

Abstract: Systems and methods are provided for discharging a high-voltage bus using semiconductor devices. A discharge system for a first voltage rail and a second voltage rail comprises a first semiconductor device coupled to a first voltage rail and a second semiconductor device coupled between the first semiconductor device and a second voltage rail. A control circuit is coupled to the first semiconductor device and the second semiconductor device. In response to a discharge condition, the control circuit is configured to activate the first semiconductor device and gradually activate the second semiconductor device, such that the energy potential between the first voltage rail and the second voltage rail is gradually dissipated through the semiconductor devices.

Abstract: A current mode control circuit uses a current comparing module to control a switching signal according to one of a plurality of current feedback signals. The current mode circuit comprises a voltage control module that generates an output voltage according to an input voltage and the switching control signal, and that generates the plurality of current feedback signals. The current comparing module outputs a control current signal that is indicative of a greater one of the plurality of current feedback signals. A current mode control module receives the control current signal and generates the switching control signal according to the control current signal.

Abstract: Systems and/or apparatus are provided for automotive electrical systems having power converters that are coupled by using a transformer. An electrical system comprises a boost converter, wherein a first winding of a transformer is coupled between the input node of the boost converter and a first reference node. The boost converter further includes a switch coupled between the first reference node and a second reference node and a diode coupled between the first reference node and the output node of the boost converter. An energy source is coupled between the input node and the second reference node and a first electrical load is coupled between the output node and the second reference node. The electrical system further comprises a voltage converter having an input coupled to a second winding of the transformer, and a second electrical load coupled to the output of the voltage converter.

Abstract: An autotransformer for use in low frequency, high power applications that uses a stack of printed wire boards constructed of a top, inner, and bottom layer including electrical trace windings circumventing the transformer core and formed in the inner layer for direct thermal contact with a heat sink interface providing a uniform and consistent heat path down to the heat sink plate. The autotransformer further includes a board to board connection employing solder cups to electrically connect between predetermined printed wire board traces. The printed wire board autotransformer also may use a non-planar interface for thermal interface with a non-planar heat sink plate surface.

Abstract: A current sensing circuit that determines an output current of a bi-directional converter circuit comprises a current transformer that receives a first current signal and that outputs a second current signal. The first current signal is indicative of the output current and flows in one of a first direction and/or a second direction. The second current signal is indicative of the first current signal. A current sensing module receives the second current signal and has a first state and a second state. A converter control module simultaneously transitions the first current signal from the first direction to the second direction and transitions the current sensing module from the first state to the second state. The converter control module transitions the current sensing module to the first state after a resetting period.