Abstract: The present disclosure relates to current source inverters (CSIs), and in particular to soft-switching current source inverters (SSCSIs). An exemplary CSI comprises a first CSI bridge, a second CSI bridge, a DC-link inductor, and a resonant tank. The first CSI bridge can be operatively connected to a first power bank. The second CSI bridge can be operatively connected to a second power bank. The DC-link inductor can be connected in series between the first and second CSI bridges. The resonant tank can be connected in parallel with the DC-link inductor.

Abstract: An exemplary embodiment of the present disclosure provides a soft-switching solid-state power transformer comprising a transformer, first and second auxiliary resonant circuits, first and second current-source inverter (CSI) bridges, and a first transformer capacitor. The first auxiliary resonant circuit can be coupled to a first winding connection of the transformer. The first auxiliary resonant circuit can comprise a resonant capacitor coupled across the first winding connection, and a resonant inductor coupled across the first winding connection in parallel with the resonant capacitor. The first CSI bridge can be coupled to the first auxiliary resonant circuit. The second auxiliary resonant circuit can be coupled to the second winding connection of the transformer. The second CSI bridge can be coupled to the second auxiliary resonant circuit. The first transformer capacitor can be coupled to a high voltage side of the first winding connection and a ground.

Abstract: An exemplary embodiment provides a power conversion system comprising a first battery module, a second battery module, first and second transformers, and first, second, and third current source converter bridges. The transformers can have low voltage sides and high voltage sides. The first bridge can be configured to connect the battery modules and the low voltage sides of the transformers. A mid-point of the serial connection of the battery modules can be connected to a mid-point of the series connection of the transformers. The second bridge can connect to the high voltage side of the first transformer and one or more ports configured to transmit electrical power to and/or receive electrical power from an electrical load and/or source. The third bridge can be configured to connect to the high voltage side of the second transformer and the one and one or more ports.

Abstract: An exemplary embodiment of the present disclosure provides a power converter system comprising a power converter. The power converter system can comprise a power converter electrically connected to a local power supply and an electrical utility grid. The power converter can comprise an output configured to exchange electrical power with the electrical utility grid. The power converter can be further configured to monitor one or more electrical parameters of the electrical utility grid over a period of time and alter one or more electrical parameters of the output of the power converter based on the monitored one or more electrical parameters of the electrical utility grid in real time using a deep learning neural network.

Abstract: A universal control (UniCon) scheme for grid-connected converters is presented herein that allows operation automatically in grid-following, grid-firming, and grid-forming modes. The converter does not need information on the grid or connected sources and loads. The converter can set its own operating point based on local measurements. The converter can operate over a wide range of typically encountered steady-state, transient, and fault conditions. UniCon realizes a universal control strategy for converters on the grid, allowing operation in distinct modes, including dispatch in grid connected mode, and automatic load sharing in islanded or microgrid mode. Under transient conditions, the converters provide inertial support and improve damping to stabilize and reduce disturbances. Multiple converters on the system do not require detailed system knowledge or low-latency communications for fast coordination, using communications when available for slow coordination and system level optimization.

Abstract: An exemplary embodiment of the present disclosure provides a resonant module and sensing circuits for use with a soft-switching current source converter. The resonant module comprises a resonant switch, a resonant inductor, and a resonant capacitor. The resonant inductor is connected in electrical series with the resonant switch. The resonant capacitor is connected in parallel with the serially connected resonant switch and resonant capacitor. The resonant module further comprises first and second sensing circuits. The first sensing circuit is configured to generate a first sensing signal indicative of when the time derivative of a voltage across the resonant capacitor is negative. The second sensing circuit is configured to generate a second sensing signal indicative of when a voltage across the resonant capacitor is less than or equal to a predetermined threshold value.

Abstract: The present disclosure relates to current source inverters (CSIs), and in particular to soft-switching current source inverters (SSCSIs). An exemplary CSI comprises a first CSI bridge, a second CSI bridge, a DC-link inductor, and a resonant tank. The first CSI bridge can be operatively connected to a first power bank. The second CSI bridge can be operatively connected to a second power bank. The DC-link inductor can be connected in series between the first and second CSI bridges. The resonant tank can be connected in parallel with the DC-link inductor.

Abstract: An embodiment of the disclosure provides a flexible multiport energy routing system comprising a first port configured to connect to an AC grid, a plurality of second ports configured to connect to a plurality of devices, a step-down transformer, a power converter stack, and a third port. The step-down transformer can a high voltage side electrically coupled to the first port and a low voltage side. The power converter stack can comprise a plurality of power converter modules each having a first converter bridge connected to the low voltage side of the step-down transformer and a second converter bridge connected to one or more of the plurality of second ports. Each of the power converter modules can have a converter transformer connected between the first and second converter bridges. The first and second converter bridges can bidirectionally manage AC and DC power flows between the first, second, and third ports.

Abstract: A synchronous reverse blocking switch for a soft-switching current source converter (SSCSC), the switch comprising: a first controlled switch; a second controlled switch connected in series to the first controlled switch; and a delay generation circuit configured to control: the second controlled switch to turn on after a delay (t_dON) from the first controlled switch turning on, and the second controlled switch to turn off after a delay (t_dOFF) from the first controlled switch turning off.

Abstract: An exemplary embodiment of the present disclosure provides a method for charging electric vehicles using service transformers on an electric utility grid. The method can comprise monitoring one or more electrical and/or thermal properties of a plurality of service transformers on an electric utility grid, and based on the monitored one or more electrical and/or thermal properties, determining that one or more of the plurality of service transformers have capacity to charge an electric vehicle.

Abstract: A soft-switching solid-state power transformer, including: a high-frequency (HF) transformer comprising first and second winding connections; a first auxiliary resonant circuit coupled to the first winding connection, the first auxiliary resonant circuit comprising: a resonant capacitor coupled across the first winding connection, a resonant inductor coupled across the first winding connection in parallel with the resonant capacitor, and a damping feature coupled across the first winding connection in series with the resonant capacitor and the resonant inductor; a first current-source inverter (CSI) bridge coupled to the first auxiliary resonant circuit, the first CSI bridge comprising reverse blocking switches configured to conduct current in one direction and block voltage in both directions; a second auxiliary resonant circuit coupled to the second winding connection; and a second CSI bridge coupled to the second auxiliary resonant circuit, the second CSI bridge comprising reverse blocking switches.

Abstract: Various examples are provided for isolated voltage optimization and control. In one example, a stackable isolated voltage optimization module (SIVOM) includes a transformer having a turns ratio between a primary winding and a secondary winding; a switching circuit configured to energize the secondary winding with a voltage provided from the three-phase power system or short the secondary winding; and a connection block configured to couple the switching circuitry to the first phase and a neutral, or to second and third phases of the three-phase power system. In another example, a system includes a SIVOM coupled to each phase of a three-phase power system, where each SIVOM comprises: a transformer and a switching circuit configured to boost or buck a voltage or change a phase angle of the phase coupled to that SIVOM by energizing a secondary winding of the transformer with a voltage provided from the three-phase power system.

Abstract: A soft-switching solid-state power transformer, including: a high-frequency (HF) transformer comprising first and second winding connections; a first auxiliary resonant circuit coupled to the first winding connection, the first auxiliary resonant circuit comprising: a resonant capacitor coupled across the first winding connection, a resonant inductor coupled across the first winding connection in parallel with the resonant capacitor, and a damping feature coupled across the first winding connection in series with the resonant capacitor and the resonant inductor; a first current-source inverter (CSI) bridge coupled to the first auxiliary resonant circuit, the first CSI bridge comprising reverse blocking switches configured to conduct current in one direction and block voltage in both directions; a second auxiliary resonant circuit coupled to the second winding connection; and a second CSI bridge coupled to the second auxiliary resonant circuit, the second CSI bridge comprising reverse blocking switches.

Abstract: Embodiments of the present disclosure can include a hybrid transformer system comprising an electrical voltage transformer comprising: a high-voltage winding, the high-voltage winding comprising a first end and a second end, the first end having a lower voltage than the second end; a plurality of taps disposed proximate the first end of the high-voltage winding; a multi-level converter coupleable to the plurality of taps of the electrical voltage transformer, the multi-level converter configured to simultaneously control voltage injection and VAR injection to the high-voltage winding of the electrical voltage transformer; and a controller electrically coupleable to the multi-level converter, such that when the multi-level converter is coupled to the plurality of taps of the electrical voltage transformer, the controller is configured to selectively inject at least one of VARs or voltage to the high-voltage winding of the electrical voltage transformer.

Abstract: Various examples are provided for isolated voltage optimization and control. In one example, a stackable isolated voltage optimization module (SIVOM) includes a transformer having a turns ratio between a primary winding and a secondary winding; a switching circuit configured to energize the secondary winding with a voltage provided from the three-phase power system or short the secondary winding; and a connection block configured to couple the switching circuitry to the first phase and a neutral, or to second and third phases of the three-phase power system. In another example, a system includes a SIVOM coupled to each phase of a three-phase power system, where each SIVOM comprises: a transformer and a switching circuit configured to boost or buck a voltage or change a phase angle of the phase coupled to that SIVOM by energizing a secondary winding of the transformer with a voltage provided from the three-phase power system.

Abstract: Embodiments of the present disclosure can include a hybrid transformer system comprising an electrical voltage transformer comprising: a high-voltage winding, the high-voltage winding comprising a first end and a second end, the first end having a lower voltage than the second end; a plurality of taps disposed proximate the first end of the high-voltage winding; a multi-level converter coupleable to the plurality of taps of the electrical voltage transformer, the multi-level converter configured to simultaneously control voltage injection and VAR injection to the high-voltage winding of the electrical voltage transformer; and a controller electrically coupleable to the multi-level converter, such that when the multi-level converter is coupled to the plurality of taps of the electrical voltage transformer, the controller is configured to selectively inject at least one of VARs or voltage to the high-voltage winding of the electrical voltage transformer.

Abstract: Power flow controllers based on Imputed DC Link (IDCL) cells are provided. The IDCL cell is a self-contained power electronic building block (PEBB). The IDCL cell may be stacked in series and parallel to achieve power flow control at higher voltage and current levels. Each IDCL cell may comprise a gate drive, a voltage sharing module, and a thermal management component in order to facilitate easy integration of the cell into a variety of applications. By providing direct AC conversion, the IDCL cell based AC/AC converters reduce device count, eliminate the use of electrolytic capacitors that have life and reliability issues, and improve system efficiency compared with similarly rated back-to-back inverter system.

Abstract: A power flow controller with a fractionally rated back-to-back (BTB) converter is provided. The power flow controller provide dynamic control of both active and reactive power of a power system. The power flow controller inserts a voltage with controllable magnitude and phase between two AC sources at the same frequency; thereby effecting control of active and reactive power flows between the two AC sources. A transformer may be augmented with a fractionally rated bi-directional Back to Back (B TB) converter. The fractionally rated BTB converter comprises a transformer side converter (TSC), a direct-current (DC) link, and a line side converter (LSC). By controlling the switches of the BTB converter, the effective phase angle between the two AC source voltages may be regulated, and the amplitude of the voltage inserted by the power flow controller may be adjusted with respect to the AC source voltages.

Abstract: A power flow controller with a fractionally rated back-to-back (BTB) converter is provided. The power flow controller provide dynamic control of both active and reactive power of a power system. The power flow controller inserts a voltage with controllable magnitude and phase between two AC sources at the same frequency; thereby effecting control of active and reactive power flows between the two AC sources. A transformer may be augmented with a fractionally rated bi-directional Back to Back (BTB) converter. The fractionally rated BTB converter comprises a transformer side converter (TSC), a direct-current (DC) link, and a line side converter (LSC). By controlling the switches of the BTB converter, the effective phase angle between the two AC source voltages may be regulated, and the amplitude of the voltage inserted by the power flow controller may be adjusted with respect to the AC source voltages.

Abstract: A power flow controller with a fractionally rated back-to-back (BTB) converter is provided. The power flow controller provide dynamic control of both active and reactive power of a power system. The power flow controller inserts a voltage with controllable magnitude and phase between two AC sources at the same frequency; thereby effecting control of active and reactive power flows between the two AC sources. A transformer may be augmented with a fractionally rated bi-directional Back to Back (BTB) converter. The fractionally rated BTB converter comprises a transformer side converter (TSC), a direct-current (DC) link, and a line side converter (LSC). By controlling the switches of the BTB converter, the effective phase angle between the two AC source voltages may be regulated, and the amplitude of the voltage inserted by the power flow controller may be adjusted with respect to the AC source voltages.