Search

US-20260128684-A1 - BI-DIRECTIONAL FIELD EFFECT TRANSISTOR (BiDFET)-BASED AC-DC POWER CONVERTER

US20260128684A1US 20260128684 A1US20260128684 A1US 20260128684A1US-20260128684-A1

Abstract

Various examples are provided related to AC-DC power conversion. In one example, a power converter includes a first bridge circuit including a plurality of bidirectional field effect transistor (BiDFET) devices; a second bridge circuit; a link coupling the first and second bridge circuits; and control circuitry to control operation of the plurality of BiDFET devices of the first bridge circuit and switching devices of the second bridge circuit. The control circuitry includes a gate-driver to provide isolated driving signals to each BiDFET device that cause continuous conductance of a first switch of the BiDFET device though a corresponding switching period and modulates a second switch of the BiDFET device through the corresponding switching period.

Inventors

  • Suyash Sushilkumar Shah
  • Subhashish Bhattacharya

Assignees

  • NORTH CAROLINA STATE UNIVERSITY

Dates

Publication Date
20260507
Application Date
20231009

Claims (19)

  1. 1 . A power converter, comprising: a first bridge circuit comprising a plurality of bidirectional field effect transistor (BiDFET) devices configured for four quadrant operation; a second bridge circuit comprising a plurality of switching devices; a link coupling the first and second bridge circuits; and control circuitry configured to control operation of the plurality of BiDFET devices of the first bridge circuit and the plurality of switching devices of the second bridge circuit, where the control circuitry comprises a gate-driver configured to provide two isolated driving signals to each BiDFET device, the isolated driving signals causing continuous conductance of a first switch of the BiDFET device though a corresponding switching period and modulates a second switch of the BiDFET device through the corresponding switching period.
  2. 2 . The power converter of claim 1 , wherein the plurality of BiDFET devices comprise monolithic SiC BiDFETs.
  3. 3 . The power converter of claim 1 , wherein the plurality of BiDFET devices comprise back-to-back transistors coupled with a common source or a common drain.
  4. 4 . The power converter of claim 1 , wherein the first bridge circuit is a three-phase bridge circuit.
  5. 5 . The power converter of claim 1 , wherein the first bridge circuit is a single-phase bridge circuit.
  6. 6 . The power converter of claim 1 , wherein the control circuitry comprises interlocking circuitry configured to coordinate switching of the plurality of BiDFET devices preventing capacitor voltage shorting or inductor current breaking.
  7. 7 . The power converter of claim 6 , wherein the interlocking circuitry is configured to coordinate withdrawal or supply of gate-pulses during a trip in response to a fault condition.
  8. 8 . The power converter of claim 7 , wherein the interlocking circuitry coordinates withdrawal of the gate-pulses from the plurality of BiDFET devices to trip the power converter.
  9. 9 . The power converter of claim 7 , wherein the trip is implemented without shorting the capacitor terminals or opening non-zero inductor current.
  10. 10 . The power converter of claim 1 , wherein the control circuitry comprises short-circuit fault protection configured to detect a short-circuit condition and adjust operation of the plurality of BiDFET devices to remove the short-circuit condition.
  11. 11 . The power converter of claim 1 , wherein the power converter is configured for bidirectional power flow via the first and second bridge circuits.
  12. 12 . The power converter of claim 11 , wherein the power converter is utilized to control power flow of an energy storage system.
  13. 13 . The power converter of claim 1 , wherein the power converter is utilized to control power flow of a photovoltaic (PV) solar cell in a solar PV energy application.
  14. 14 . The power converter of claim 1 , wherein modulation of the second switch is based upon polarity of a blocking voltage when it is turned-off.
  15. 15 . The power converter of claim 1 , wherein the gate-driver is configured to independently control the two isolated driving signals.
  16. 16 . The power converter of claim 1 , wherein the gate-driver comprises digital isolators for the isolated driving signals.
  17. 17 . The power converter of claim 1 , comprising a second-order capacitor-inductor (CL) filter at an output of the first bridge circuit, the second-order CL filter configured to attenuate switching frequency harmonics generated by the power converter.
  18. 18 . The power converter of claim 17 , wherein the second-order CL filter comprise a parallel resistor-capacitor (RC) damping branch.
  19. 19 . The power converter of claim 17 , wherein the second-order CL filter maintains a total harmonic distortion of 5% or less.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority to, and the benefit of, co-pending U.S. provisional application entitled “Bi-Directional Field Effect Transistor (BiDFET)-Based AC-DC Power Converter” having Ser. No. 63/414,510, filed Oct. 9, 2022, which is hereby incorporated by reference in its entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support under grant number DE-EE0008345 awarded by the U.S. Department of Energy—Office of Energy Efficiency and Renewable Energy. The government has certain rights in the invention. SUMMARY Aspects of the present disclosure are related to AC-DC power conversion. In one aspect, among others, a power converter comprises a first bridge circuit comprising a plurality of bidirectional field effect transistor (BiDFET) devices configured for four quadrant operation; a second bridge circuit comprising a plurality of switching devices; a link coupling the first and second bridge circuits; and control circuitry configured to control operation of the plurality of BiDFET devices of the first bridge circuit and the plurality of switching devices of the second bridge circuit, where the control circuitry comprises a gate-driver configured to provide two isolated driving signals to each BiDFET device, the isolated driving signals causing continuous conductance of a first switch of the BiDFET device though a corresponding switching period and modulates a second switch of the BiDFET device through the corresponding switching period. In one or more aspects, the plurality of BiDFET devices can comprise monolithic SiC BiDFETs. In one or more aspects, the plurality of BiDFET devices can comprise back-to-back transistors coupled with a common source or a common drain. The first bridge circuit can be a three-phase bridge circuit or a single-phase bridge circuit. The control circuitry can comprise interlocking circuitry configured to coordinate switching of the plurality of BiDFET devices preventing capacitor voltage shorting or inductor current breaking. The interlocking circuitry can be configured to coordinate withdrawal or supply of gate-pulses during a trip in response to a fault condition. The interlocking circuitry can coordinate withdrawal of the gate-pulses from the plurality of BiDFET devices to trip the power converter. The trip can be implemented without shorting the capacitor terminals or opening non-zero inductor current. In various aspects, the control circuitry can comprise short-circuit fault protection configured to detect a short-circuit condition and adjust operation of the plurality of BiDFET devices to remove the short-circuit condition. The power converter can be configured for bidirectional power flow via the first and second bridge circuits. The power converter can be utilized to control power flow of an energy storage system. The power converter can be utilized to control power flow of a photovoltaic (PV) solar cell in a solar PV energy application. Modulation of the second switch can be based upon polarity of a blocking voltage when it is turned-off. The gate-driver can be configured to independently control the two isolated driving signals. The gate-driver can comprise digital isolators for the isolated driving signals. The power converter can comprise a second-order capacitor-inductor (CL) filter at an output of the first bridge circuit, the second-order CL filter configured to attenuate switching frequency harmonics generated by the power converter. The second-order CL filter can comprise a parallel resistor-capacitor (RC) damping branch. The second-order CL filter can maintain a total harmonic distortion of 5% or less. Other systems, methods, features, and advantages of the present disclosure will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure, and be protected by the accompanying claims. In addition, all optional and preferred features and modifications of the described embodiments are usable in all aspects of the disclosure taught herein. Furthermore, the individual features of the dependent claims, as well as all optional and preferred features and modifications of the described embodiments are combinable and interchangeable with one another. BACKGROUND The declining capital and operational costs of solar power has resulted in its rapid adoption in the commercial and industrial energy generation. The 2020 Annual Technology Baseline data from National Renewable Energy Laboratory (NREL) suggests that with ‘moderate’ technology outlook, the levelized cost of energy per MWh for commercial, distributed solar in cities like Los Angeles will reduce from the baseline of US$ 70 to US$32 in 2030. A key component in distributed solar installed for