Georgia Tech Research Corporation

Wisconsin Alumni Research Foundation

Varentec, Inc.

Electric Power Research Institute Incorporated

Soft Switching Technologies Corporation

Innovolt, Inc.

Deepakraj M Divan

Anish Prasai

Rohit Moghe

Donald W Novotny

Rajendra Prasad Kandula

Robert Donald Lorenz

Robert S Schneider

Franklin Lambert

Andrew Dillon

Subhashish Bhattacharya

Keith W Klontz

Nasser H Kutkut

Po-Tai Cheng

Hao Chen

William E Brumsickle

William R Kranz

Amrit Iyer

Chingchi Chen

Robert Edwin Schneider

Thomas Anthony Lipo

Ronald Gordon Harley

Robert H Lasseter

Harjeet Johal

Mickael J Mauger

Shreyas Bhalchandra Kulkarni

Giri Venkataramanan

Aniruddh Marellapudi

Joy Mazumdar

Glen A Luckjiff

Liran Zheng

Karthik Kandasamy

Jyoti Sastry

Nassar H Kutkut

Alexander L Julian

Mukul Chandorkar

Ian Dobson

Rik W DeDoncker

Herman L Wiegman

Herbert L Hess

Glen Luckjiff

Randal W Gascoigne

Jorge Hernendez

John G Wohlbier

Mustansir H Kheraluwala

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.

Synchronous reverse blocking switch for soft-switching current source converters and soft-switching current source converters including the same

An exemplary embodiment provides a current sensor comprising a printed circuit board (PCB), a Rogowski coil, and a controller. The PCB can comprise an aperture configured to receive a conductor carrying an alternating electrical current. The Rogowski coil can be positioned on the PCB along a perimeter of the aperture. The controller can be in electrical communication with the Rogowski coil and configured to generate an output signal indicative of the alternating electric current carried by the conductor. The current sensor can be configured to measure the alternating electric current relative to a full scale at a resolution of 1000:1 and at an accuracy within 1%, wherein the full scale can range over 5000:1.

Current sensors employing Rogowski coils and methods of using same

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.

Transformers, converters, and improvements to the same

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.

Stackable isolated voltage optimization module

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.

Hybrid transformer systems and methods

A plurality of edge of network grid volt ampere reactive (VAR) sources are provided in a power system in order to effectuate control at a customer level, which in turn effectuates control at a feeder level, which in turn effectuates control of an entire power system or wide area electric grid network. By optimally selecting voltage setpoints and applying such voltage setpoints to the plurality of edge of network grid VAR sources, the power system can be configured to self-balance, power factor compensation can be determined without the need for measuring load power factor. Moreover, traditionally volatile voltages at the feeder can be flattened, and VAR control can be realized.

Optimizing voltage and VAR on the electric grid using distributed VAR sources

By virtue of the ability to vary local load via inverter (e.g., solar PV inverter) volt-ampere reactive power (VAR) injection, local demand and energy consumption can be controlled at a system level. Utilities that provide solar PV systems to consumers can leverage this ability to reduce the purchase of high cost energy. Moreover, revenue for such utilities can be maximized. For example, such localized voltage and VAR control allow for precise control to achieve, e.g., plus or minus about two percent of kW and kWHr of power consumed at a node.

Controlling demand and energy through photovoltaic inverters delivering VARs

Systems and methods for an edge of network voltage control of a power grid are described. A system includes a distribution power network, a plurality of loads (at or near an edge of the distribution power network), and a plurality of shunt-connected, switch-controlled volt ampere reactive (VAR) sources also located at the edge or near the edge of the distribution power network where they may each detect a proximate voltage. The VAR source can determine whether to enable a VAR compensation component therein based on the proximate voltage and adjust network VAR by controlling a switch to enable the VAR compensation component. Further still, each of the VAR sources may be integrated within a customer-located asset, such as a smart meter, and a multitude of such VAR sources can be used to effectuate a distributed controllable VAR source (DCVS) cloud network.

Systems and methods for edge of network voltage control of a power grid

Various examples are provided for soft switching solid state transformers and converters, and their operation and application. In one example, a soft switching solid state power transformer includes a high frequency (HF) transformer; first and second auxiliary resonant circuits coupled to the HF transformer; and first and second current-source inverter (CSI) bridges coupled to the corresponding first auxiliary resonant circuits. The first and second CSI bridges include reverse blocking switch assemblies that conduct current in one direction and block voltage in both directions. In another example, a reactive power compensator includes a high frequency (HF) transformer, first, second and third auxiliary resonant circuits coupled to the HF transformer, and first, second and third current-source inverter (CSI) bridges coupled to the corresponding first auxiliary resonant circuits. In another example, a converter includes an auxiliary resonant circuit coupled across an inductor and first and second CSI bridges coupled across the inductor.

Soft switching solid state transformers and converters

The present invention describes systems and methods for determining current flow through a current-carrying utility asset. An exemplary embodiment can include measuring a first magnetic induction value at a first location near a targeted current-carrying utility asset and a second magnetic induction value at a second location near the targeted asset where the first location is a known distance from the second location; determining a correlation between a spatial angle and an electrical phase angle between the targeted asset and a second asset where the second asset contributes a first and second error component to the first and second magnetic induction values respectively; estimating error values for the first and second error components using the correlation between the spatial angle and the electrical phase angle; and estimating a current flowing through the targeted asset using the first and second magnetic induction values, the known distance, and the error values.

Systems and methods for determining current flow through a utility asset

Methods and systems of network voltage regulating transformers are provided. A network voltage regulating transformer (NVRT) may provide voltage transformation, isolation, and regulation. A NVRT may further provide power factor corrections. Multiple NVRTs may operate autonomously and collectively thereby achieving an edge of network voltage control when installed to a power system. A NVRT comprises a transformer, a VAR source, and a control module. The input current (i.e., the current through the primary side of the transformer), the output current (i.e., the current through the secondary side of the transformer), and/or the output voltage (i.e., the voltage across the secondary side of the transformer) may be monitored.

Methods and systems of network voltage regulating transformers

Systems and methods for controlling grid voltage include a distribution power network and one or more smart inverters at or near the edge of the distribution power network, each smart inverter configured to absorb or insert VARs to control the voltage based on a reference Q value, wherein the reference Q value is calculated by a reference Q calculator. A reference Q calculator includes a processor and a non-transitory computer readable memory with software embedded thereon, the software configured to cause the processor to receive a voltage measurement taken at or near the edge of a power distribution grid, a voltage band value, and a voltage set point value, determine a difference, e, between the voltage measurement and the voltage set point, generate a new reference Q value if an absolute value of eis greater than the voltage band value, and cause the smart inverter to either absorb or insert VARs depending on the sign of e.

Zero droop voltage control for smart inverters

Dynamic power flow controllers are provided. A dynamic power flow controller may comprise a transformer and a power converter. The power converter is subject to low voltage stresses and not floated at line voltage. In addition, the power converter is rated at a fraction of the total power controlled. A dynamic power flow controller controls both the real and the reactive power flow between two AC sources having the same frequency. A dynamic power flow controller inserts a voltage with controllable magnitude and phase between two AC sources; thereby effecting control of active and reactive power flows between two AC sources.

Dynamic power flow controllers

Growing community of inventors

San Jose, CA, United States of America

Deepakraj M Divan