Abstract: A high voltage direct current (HVDC) converter system includes a line commutated converter (LCC) configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in only one direction. The HVDC converter system also includes a buck converter configured to convert a plurality of AC voltages and currents to a regulated DC voltage of one of positive and negative polarity and a DC current transmitted in one of two directions. The LCC and the buck converter are coupled in parallel to an AC conduit and are coupled in series to a DC conduit. The HVDC converter system further includes a filtering device coupled in parallel to the buck converter through the AC conduit. The filtering device is configured to inject AC current having at least one harmonic frequency into the AC conduit.

Abstract: A method and system for a commutation control circuit are provided. The system includes an integrating voltage counter electrically coupled to an electrical power bus, wherein the integrating voltage counter is configured to integrate over time a voltage signal received from the power bus and to generate a trigger signal when the integrated voltage signal equals a predetermined count. The system also includes a plurality of transistor pairs configured to receive a trigger signal generated by the integrating voltage counter and electrically coupled to respective windings of a motor.

Abstract: A sub-sea power delivery system includes a plurality of modular power converter building blocks on each of the power source side and the sub-sea load side that are stacked and interconnected to meet site expansion requirements and electrical load topologies. The power delivery system comprises a system DC transmission link/bus, wherein the system DC link is configured to carry HVDC or MVDC power from an onshore utility or topside power source to multiple sub-sea load modules. The stacked modular power converter topology on the sub-sea side of the sub-sea power delivery system is symmetrical with the stacked modular power converter topology on the on-shore/top-side of the sub-sea power delivery system.

Abstract: A power converter is presented. The power converter includes at least one leg, the at least one leg includes a first string, where the first string includes a plurality of controllable semiconductor switches, a first connecting node, and a second connecting node, and where the first string is operatively coupled across a first bus and a second bus. Furthermore, the at least one leg includes a second string operatively coupled to the first string via the first connecting node and the second connecting node, where the second string includes a plurality of switching units. A method for power conversion is also presented.

Abstract: An electronics power system includes a plurality of substantially identical power electronic modules. Each power electronic module includes a single-phase DC/AC inverter having an output side. Each power electronic module further includes a medium/high-frequency-isolated DC/DC current-to-voltage converter having an input side. The medium/high-frequency-isolated DC/DC current-to-voltage converter drives the single-phase DC/AC inverter. Each DC/DC converter and its corresponding DC/AC inverter are connected back-to-back sharing a common DC-link. The plurality of power electronics modules is stacked together in series at the input side and in parallel or series/parallel at the output side.

Abstract: A high voltage, high power multi-level drive structure includes a plurality of neutral-point-piloted (NPP) converter cells stacked together. At least one clamping diode is connected to one or many NPP converter cell to provide a neutral-point-pilot-clamped (NPPC) converter structure. Flying capacitors connected to the NPPC converter structure yield a neutral-point-clamped-flying-capacitor converter cell structure.

Abstract: A load bypass switch enables continuous power to remote loads in the event of 1) failure of one or more remote loads, or 2) faults within the remote loads, within a dc power system. The bypass switch utilizes the passive components of the dc loads or inverters and therefore reduces overall component count. A black start method for the remote dc system uses the same passives present inside the loads/inverters and simultaneously uses some of the features of the bypass switch. A bypass-module-yard uses multiple bypass switches enabling continuous power to the remote loads in the event of failure of one or more power distribution cables (in-feed to the remote loads) located remotely in the dc system.

Abstract: A power conversion system includes a power transformer for receiving AC power at a first voltage from an input side and for delivering AC power at a second voltage to an output side. A power converter is also included in the power conversion system wherein the power converter includes an input side converter on the input side and an output side converter on the output side coupled through a plurality of DC links. A converter controller in the power converter provides control signals to the input side converter and the output side converter for regulating an active power and a reactive power flow through the power converter. Each of the input side converters and the output side converters includes at least two power converter transformers coupled between respective power converter bridges coupled to the plurality of DC links and the input side or to the plurality of DC links and the output side.

Abstract: A power conversion system includes a power transformer for receiving AC power at a first voltage from an input side and for delivering AC power at a second voltage to an output side. A power converter is also included in the power conversion system wherein the power converter includes an input side converter on the input side and an output side converter on the output side coupled through a plurality of DC links. A converter controller in the power converter provides control signals to the input side converter and the output side converter for regulating an active power and a reactive power flow through the power converter. Each of the input side converters and the output side converters includes at least two power converter transformers coupled between respective power converter bridges coupled to the plurality of DC links and the input side or to the plurality of DC links and the output side.

Abstract: A device to attenuate EMI between a source and a load is provided. The device includes a first cable to electrically couple the source and the load and a second cable positioned adjacent to the first cable and configured to attenuate a common-mode current.

Abstract: A method and system for a commutation control circuit are provided. The system includes an integrating voltage counter electrically coupled to an electrical power bus, wherein the integrating voltage counter is configured to integrate over time a voltage signal received from the power bus and to generate a trigger signal when the integrated voltage signal equals a predetermined count. The system also includes a plurality of transistor pairs configured to receive a trigger signal generated by the integrating voltage counter and electrically coupled to respective windings of a motor.

Abstract: A method for determining rotor position comprising sending a signal to a stator, receiving a first signal indicative of a first estimated stator inductance, and receiving a second signal indicative of a second estimated stator inductance. The method further includes, calculating a first rotor position angle using a function including the first estimated stator inductance and the second estimated stator inductance.

Abstract: A system for the transmission of a direct current (DC) at a medium voltage level includes a system DC link configured to carry power from a source to a load module. The load module includes a DC-to-DC voltage step-down converter, a DC-to-AC inverter coupled downstream to the DC-to-DC voltage step-down converter, and a system AC link for carrying power from the load module to a motor system on a load side of the system AC link. The system is effective for delivering power over distances that are greater than 30 kilometers, and for delivery of power from an on-shore to offshore and sub-sea load.

Abstract: A direct current (DC) transmission and distribution system includes a system DC link configured for carrying power from a source to a plurality of loads {16} and DC to alternating current (AC) power converter modules coupled in series to the system DC link on a load side of the system DC link

Abstract: A device to attenuate EMI between a source and a load is provided. The device includes a first cable to electrically couple the source and the load and a second cable positioned adjacent to the first cable and configured to attenuate a common-mode current.

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 sub-sea power delivery system includes a plurality of modular power converter building blocks on each of the power source side and the sub-sea load side that are stacked and interconnected to meet site expansion requirements and electrical load topologies. The power delivery system comprises a system DC transmission link/bus, wherein the system DC link is configured to carry HVDC or MVDC power from an onshore utility or topside power source to multiple sub-sea load modules. The stacked modular power converter topology on the sub-sea side of the sub-sea power delivery system is symmetrical with the stacked modular power converter topology on the on-shore/top-side of the sub-sea power delivery system.

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 method for determining rotor position comprising sending a signal to a stator, receiving a first signal indicative of a first estimated stator inductance, and receiving a second signal indicative of a second estimated stator inductance. The method further includes, calculating a first rotor position angle using a function including the first estimated stator inductance and the second estimated stator inductance.

Abstract: A power generation system for supplying a resultant output voltage is provided. The system comprises a power converter system. The power converter system comprises at least two power converter bridges, each configured for switching at a low frequency and generating a corresponding converter output voltage including a fundamental voltage component and harmonic components, and at least two power converter transformers. Each power converter bridge is coupled to a primary winding of a corresponding power converter transformer and a secondary winding of one power converter transformer is coupled to a secondary winding of a second power converter transformer. The resultant output voltage comprises a sum of the fundamental voltage components of each converter output voltage.