Search

EP-4736288-A2 - MEDIUM VOLTAGE DIRECT CURRENT SOLAR PLANT ARCHITECTURE

EP4736288A2EP 4736288 A2EP4736288 A2EP 4736288A2EP-4736288-A2

Abstract

A solar power generation system is provided. The solar power generation system includes a plurality of photovoltaic (PV) arrays configured to generate low voltage direct current (LVDC) power, a plurality of DC to DC converters, each of the plurality of DC to DC converters configured to convert the LVDC power to medium voltage DC (MVDC) power, a plurality of branch MVDC busses, a main MVDC bus configured to receive MVDC power from each of the plurality of branch MVDC busses, at least one inverter configured to receive MVDC power from the main MVDC bus and convert the MVDC power to medium voltage alternating current (MVAC) power, and a distribution transformer configured to receive MVAC power from the at least one inverter and convert the MVAC power to high voltage AC power.

Inventors

  • HAWES, NATHANIEL BENEDICT
  • SCHELENZ, OWEN
  • PANT, SIDDHARTH

Assignees

  • GE Grid Solutions LLC

Dates

Publication Date
20260506
Application Date
20240626

Claims (20)

  1. 1. A solar power generation system comprising: a plurality of photovoltaic (PV) arrays configured to generate low voltage direct current (LVDC) power; a plurality of DC to DC converters, each of said plurality of DC to DC converters configured to receive LVDC power from at least one of said plurality of PV arrays and convert the LVDC power to medium voltage DC (MVDC) power; a plurality of branch MVDC busses, each of said plurality of branch MVDC busses configured to convey MVDC power from at least one of the plurality of DC to DC converters; a main MVDC bus configured to receive MVDC power from each of said plurality of branch MVDC busses; at least one inverter configured to receive MVDC power from said main MVDC bus and convert the MVDC power to medium voltage alternating current (MV AC) power; and a distribution transformer configured to receive MV AC power from said at least one inverter and convert the MV AC power to high voltage AC power.
  2. 2. The solar power generation system of Claim 1, further comprising a plurality of diodes, each of said plurality of diodes electrically coupled between one of said plurality of branch MVDC busses and said main MVDC bus.
  3. 3. The solar power generation system of Claim 1, further comprising an energy storage system configured to store energy generated by at least some of said plurality of PV arrays.
  4. 4. The solar power generation system of Claim 3, wherein said energy storage system is electrically coupled to said main MVDC bus.
  5. 5. The solar power generation system of Claim 1 , further comprising a plurality 7 of filters, each of said plurality of filters electrically coupled between one of said plurality of branch MVDC busses and said main MVDC bus.
  6. 6. The solar power generation system of Claim 1 , wherein the LVDC power has a bipolar voltage of about ±1.5 kilovolts.
  7. 7. The solar power generation system of Claim 1, wherein the MVDC power has a bipolar voltage in a range of about ±10 kilovolts to about ±40 kilovolts.
  8. 8. A method for operating a solar power generation system, said method comprising: generating, by a plurality of photovoltaic (PV) arrays, low voltage direct current (LVDC) power; converting, by a plurality of DC to DC converters configured to receive LVDC power from at least one of the plurality of PV arrays, the LVDC power to medium voltage DC (MVDC) power; conveying, by a plurality' of branch MVDC busses, MVDC power from at least one of the plurality of DC to DC converters to a main MVDC bus; converting, by at least one inverter configured to receive MVDC power from the main MVDC bus, the MVDC power to medium voltage alternating current (MV AC) power; and converting, by a distribution transformer configured to receive MV AC power from the at least one inverter, the MV AC power to high voltage AC power.
  9. 9. The method of Claim 8, wherein each of a plurality of diodes is electrically coupled between one of the plurality of branch MVDC busses and the main MVDC bus.
  10. 10. The method of Claim 8, further comprising storing energy generated by at least some of the plurality of PV arrays in an energy storage system.
  11. 1 1. The method of Claim 10, wherein the energy storage system is electrically coupled to the main MVDC bus.
  12. 12. The method of Claim 8, wherein a plurality of filters are electrically coupled between one of the plurality of branch MVDC busses and the main MVDC bus.
  13. 13. The method of Claim 8, wherein the LVDC power has a bipolar voltage of about ±1.5 kilovolts.
  14. 14. The method of Claim 8, wherein the MVDC power has a bipolar voltage in a range of about ±10 kilovolts to about ±40 kilovolts.
  15. 1 . A solar power distribution system comprising: a plurality of direct current (DC) to DC converters, each of said plurality of DC to DC converters configured to receive low voltage DC (LVDC) power from at least one of a plurality of photovoltaic (PV) arrays and convert the LVDC power to medium voltage DC (MVDC) power; a plurality of branch MVDC busses, each of said plurality of branch MVDC busses configured to convey MVDC power from at least one of the plurality of DC to DC converters; a main MVDC bus configured to receive MVDC power from each of said plurality of branch MVDC busses; at least one inverter configured to receive MVDC power from said main MVDC bus and convert the MVDC power to medium voltage alternating current (MV AC) power; and a distribution transformer configured to receive MV AC power from said at least one inverter and convert the MV AC power to high voltage AC power.
  16. 16. The solar power distribution system of Claim 15, further comprising a plurality of diodes, each of said plurality of diodes electrically coupled between one of said plurality of branch MVDC busses and said main MVDC bus.
  17. 17. The solar power distribution system of Claim 15, further comprising an energy storage system configured to store energy generated by at least some of said plurality of PV arrays.
  18. 18. The solar power distribution system of Claim 17, wherein said energy storage system is electrically coupled to said main MVDC bus.
  19. 19. The solar power distribution system of Claim 15, further comprising a plurality of filters, each of said plurality of filters electrically coupled between one of said plurality of branch MVDC busses and said main MVDC bus.
  20. 20. The solar power distribution system of Claim 15, wherein the LVDC power has a bipolar voltage of about ±1.5 kilovolts.

Description

MEDIUM VOLTAGE DIRECT CURRENT SOLAR PLANT ARCHITECTURE CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority of U.S. Provisional Application No. 63/510,520, filed June 27, 2023, and entitled “MEDIUM VOLTAGE DIRECT CURRENT SOLAR PLANT ARCHITECTURE,” the contents and disclosures of which are hereby incorporated by reference in their entirety. BACKGROUND [0002] The field of the disclosure relates generally to power generation facilities, and more particularly, to an architecture for a solar power generation facility. [0003] The power density of a solar plant is ultimately dictated by the irradiance of solar radiation at the earth’s surface. Due to the low value of irradiance, solar plant design becomes a cost optimization problem in how to efficiently collect a low density power from a geographically large area, and concentrate it to a single point, referred to as point of interconnection (POI), where it can enter the electric grid. At least some current utility-scale solar plants collect power emitted from solar panels up to a 1500 volts direct current (DC) level, transmit that power to a local inverter hub where it is stepped up to medium voltage alternating current (AC) power, and then transmit the AC power to the POI for step-up to transmission voltage. As with nearly all electrical systems, the collection and transmission of power is most efficiently performed at high voltage and low current. However, higher safety and insulation costs are typically associated with high voltage levels of high voltage transmission. A solar plant architecture having an increased cost efficiency and an increased energy production efficiency is therefore desirable. BRIEF DESCRIPTION [0004] In one aspect, a solar power generation system is provided. The solar power generation system includes a plurality of photovoltaic (PV) arrays configured to generate low voltage direct current (LVDC) power. The solar power generation system further includes a plurality of DC to DC converters, each of the plurality of DC to DC converters configured to receive LVDC power from at least one of the plurality of PV arrays and convert the LVDC power to medium voltage DC (MVDC) power. The solar power generation system further includes a plurality of branch MVDC busses, each of the plurality of branch MVDC busses configured to convey MVDC power from at least one of the plurality of DC to DC converters. The solar power generation system further includes a main MVDC bus configured to receive MVDC power from each of the plurality of branch MVDC busses. The solar power generation system further includes at least one inverter configured to receive MVDC power from the main MVDC bus and convert the MVDC power to medium voltage alternating cunent (MV AC) power. The solar power generation system further includes a distribution transformer configured to receive MV AC power from the at least one inverter and convert the MV AC power to high voltage AC power. [0005] In another aspect, a method for operating a solar power generation system is provided. The method includes generating, by a plurality of PV arrays, LVDC power. The method further includes converting, by a plurality of DC to DC converters configured to receive LVDC power from at least one of the plurality of PV arrays, the LVDC power to MVDC power. The method further includes conveying, by a plurality of branch MVDC busses, MVDC power from at least one of the plurality of DC to DC converters to a main MVDC bus. The method further includes converting, by at least one inverter configured to receive MVDC power from the main MVDC bus, the MVDC power to MV AC power. The method further includes converting, by a distribution transformer configured to receive MV AC power from the at least one inverter, the MV AC power to high voltage AC power. [0006] In another aspect, a solar power distribution system is provided. The solar power distribution system includes a plurality of DC to DC converters, each of the plurality of DC to DC converters configured to receive LVDC power from at least one of a plurality of PV arrays and convert the LVDC power to MVDC power. The solar power distribution system further includes a plurality of branch MVDC busses, each of the plurality of branch MVDC busses configured to convey MVDC power from at least one of the plurality of DC to DC converters. The solar power distribution system further includes a main MVDC bus configured to receive MVDC power from each of the plurality of branch MVDC busses. The solar power distribution system further includes at least one inverter configured to receive MVDC power from the main MVDC bus and convert the MVDC power to MV AC power. The solar power distribution system further includes a distribution transformer configured to receive MV AC power from the at least one inverter and convert the MV AC power to high voltage AC power. BRIEF DESCRIPTION OF DRAWINGS [0007] These and other features, aspects, and