Systems and methods for detecting and correcting a suboptimal operation of one or more inverters in a multi-inverter system

• US 8,922,061 B2
• Filed: 07/20/2010
• Issued: 12/30/2014
• Est. Priority Date: 03/22/2010
• Status: Active Grant

• Current Assignee: Tigo Energy, Inc
• Original Assignee: Tigo Energy, Inc
• Inventors: Arditi, Sam
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): PEREZ BORROTO, ALFONSO
• Application Number:
  US12/840,228
• Publication Number:
  US 20110227411A1
• Time in Patent Office: 1,624 Days
• Field of Search: 307/18, 307/82, 307/43, 361/18, 136/290, 136/293, 136/244
• US Class Current: 307/82
• CPC Class Codes: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence
• CPC Class Codes: Y10S 136/29 Testing, calibrating, treating, e.g. aging
• CPC Class Codes: Y10S 136/293 Circuits

Abstract

Provided is a system and method for detecting and correcting a suboptimal operation of one or more maximum power point tracking (MPPT) devices in a solar photovoltaic power generation (SPVPG) system. MPPT devices may become stuck in a local maximum in a power curve and fail to reach an optimal maximum power point. Described herein are methods and systems for detecting sub-optimal performance of an MPPT device and managing components within the SPVPG system to cause the MPPT device to track a different maximum power point.

Claims

1. A method comprising:

receiving first power output information from a maximum power point tracking (MPPT) device configured to track a maximum power point of a solar power production system;

wherein the solar power production system contains a plurality of direct current (DC) to DC converting devices each connected with at least one of a plurality of solar panel units within the solar power production system;

making a determination, from the first power output information, that maximum power point tracking performed by the MPPT device on the solar power production system has been trapped at a first state of operating the solar power production system for a predetermined period of time, the first state being sub-optimal for the solar power production system; and

based on the determination, transmitting a first instruction to a first device, selected from the group consisting of the MPPT device and the plurality of DC to DC converting devices, to change a control operation of the first device.

2. The method of claim 1, wherein the first device is the MPPT device.

3. The method of claim 1, wherein the first device is one of the DC to DC converting devices.

4. The method of claim 3, wherein the first device includes a management unit configured to connect a solar panel unit of the solar power production system to the MPPT device.

5. The method of claim 4, wherein the management unit performs maximum power point (MPP) tracking for the solar panel unit.

6. The method of claim 4, further comprising:

receiving measurement data from the management unit; and

wherein the determination is further based on the measurement data.

7. The method of claim 1, further comprising:

receiving second power output information from a second MPPT device configured to track a maximum power point of a separate solar power production system; and

wherein the determination is based on comparing the first power output information and the second power output information.

8. The method of claim 1, wherein the first instruction is to restart the first device.

9. The method of claim 1, wherein the MPPT device is integrated in an inverter;

wherein the inverter is adapted to convert electricity generated by the plurality of solar panel units of the solar power production system from DC to alternating current (AC).

10. The method of claim 1, wherein the first instruction is to operate temporarily at least one solar panel unit in a third state that is less optimal than the first state.

11. The method of claim 1, wherein the first instruction is to shut down the MPPT device.

12. The method of claim 1, wherein each respective solar panel unit of the plurality of solar panel units has a local management unit comprising:

a circuit to measure operating parameters of the respective solar panel unit;

a communicator to transmit the operating parameters and to receive instructions; and

a converter coupled to the respective solar panel to output electricity generated by the respective solar panel, the converter being one of the plurality of DC to DC converting devices;

wherein the method further comprises;

receiving operating parameters transmitted from the communicator of the local management unit of the each respective solar panel unit of the plurality of solar panel units;

computing control parameters for the converter of the local management unit of the each respective solar panel unit of the plurality of solar panel units based on the operating parameters received from the communicator of the local management unit of the each respective solar panel unit of the plurality of solar panel units; and

transmitting the control parameters to the communicator of the local management unit of the each respective solar panel unit of the plurality of solar panel units to control the converter of the local management unit of the each respective solar panel unit of the plurality of solar panel units.

13. A solar photovoltaic power generation system, comprising:

a plurality of photovoltaic panels;

a plurality of direct current (DC) to DC converting devices each configured to adjust an output of a corresponding panel of the plurality of photovoltaic panels;

a maximum power point tracking (MPPT) device adapted to control the plurality of photovoltaic panels;

a master management unit (MMU) adapted to;

receive information about a power output of the plurality of photovoltaic panels,

make a determination, based on the information, that maximum power point tracking performed by the MPPT device on the plurality of photovoltaic panels has been trapped in a sub-optimal state of operating the plurality of photovoltaic panels for a period of time, and

instruct a first device, selected from the group consisting of the MPPT device and the DC to DC converting devices to change a control operation of the first device, based on the determination about the MPPT device.

14. The solar photovoltaic power generation system of claim 13, wherein the MMU is further adapted to instruct the first device to restart, based on the determination about the MPPT device.

15. The solar photovoltaic power generation system of claim 13, wherein the first device is one of the DC to DC converting devices.

16. The solar photovoltaic power generation system of claim 15, wherein the DC to DC converting devices connect the plurality of photovoltaic panels into one or more strings.

17. The solar photovoltaic power generation system of claim 13, further comprising:

a plurality of local management units each containing a corresponding one of the direct current (DC) to DC converting devices and adapted to communicate information about a power output of the corresponding panel to the MMU.

18. An apparatus adapted to control a solar power production system, the apparatus comprising:

a memory to store a first executable program;

a microprocessor to execute the first executable program; and

a communications device coupled to the microprocessor to receive first power output information from a maximum power point tracking (MPPT) device configured to track a maximum power point of the solar power production system;

wherein the solar power production system contains a plurality of direct current (DC) to DC converting devices each connected with at least one of a plurality of solar panel units within the solar power production system;

wherein the microprocessor is adapted to make a determination in accordance with the first executable program, from the first power output information, that maximum power point tracking performed by the MPPT device on the solar power production system has been trapped at a first state of operating the solar power production system for a predetermined period of time, the first state being sub-optimal for the solar power production system; and

wherein the communications device is adapted to transmit, in response to the determination, a first instruction to a first device, selected from the plurality of DC to DC converting devices, to change a control operation of the first device.

19. The apparatus of claim 18, wherein the first instruction is to operate temporarily at least one solar panel unit in a third state that is less optimal than the first state.

20. The apparatus of claim 18, wherein the communications device is further adapted to receive second power output information from a second MPPT device configured to track a maximum power point of a separate solar power production system;

and

wherein the determination is based on comparing the first power output information and the second power output information.