Method for distributed power harvesting using DC power sources

• US 10,097,007 B2
• Filed: 05/12/2017
• Issued: 10/09/2018
• Est. Priority Date: 12/06/2006
• Status: Active Grant

• Current Assignee: Solaredge Technologies Incorporated
• Original Assignee: Solaredge Technologies Incorporated
• Inventors: Adest, Meir, Handelsman, Lior, Galin, Yoav, Fishelov, Amir, Sella, Guy
• Primary Examiner(s): AMAYA, CARLOS DAVID
• Application Number:
  US15/593,942
• Publication Number:
  US 20170250541A1
• Time in Patent Office: 515 Days
• Field of Search: 307 77, 307 82
• CPC Class Codes: H02J 2300/26 involving maximum power point tracking control for photovoltaic sources maximum power point systems in particular G05F1/67
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 3/18 Arrangements for adjusting, eliminating or compensating reactive power in networks for adjustment of voltage H02J3/16
• CPC Class Codes: H02J 3/38 Arrangements for parallely feeding a single network by two or more generators, converters or transformers
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/0077 Plural converter units whose outputs are connected in series
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 7/44 by static converters
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving

Abstract

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Claims

1. A method comprising:

coupling each of a plurality of DC power sources to a different DC power converter of a plurality of DC power converters;

coupling each DC power converter of the plurality of DC power converters in series to form a serial string;

limiting power output by each of the plurality of DC power converters until a predetermined event occurs;

responsive to the predetermined event, regulating a first parameter of the serial string according to a set value, thereby forcing a second parameter of the serial string to vary according to the power output by each of the plurality of DC power converters.

2. The method of claim 1, wherein the predetermined event is a least one of:

a load drawing current from the serial string, and

an enable signal being received by the plurality of DC power converters.

3. The method of claim 1, further comprising individually operating each of the plurality of DC power converters to monitor and report power related data.

4. The method of claim 3, wherein, for each of the plurality of DC power converters, the power related data includes at least one of input current to the DC power converter, input voltage to the DC power converter, temperature of the DC power source, input power to the DC power converter, and available illumination.

5. The method of claim 1, wherein the first parameter of the serial string is voltage and the second parameter of the serial string is current.

6. The method of claim 1, wherein the first parameter of the serial string is current and the second parameter of the serial string is voltage.