DISTRIBUTED MAXIMUM POWER POINT TRACKING SYSTEM, STRUCTURE AND PROCESS

• US 20080238195A1
• Filed: 03/26/2008
• Published: 10/02/2008
• Est. Priority Date: 03/27/2007
• Status: Active Grant

• Current Assignee: Solaredge Technologies Incorporated
• Original Assignee: Newdoll Enterprises LLC
• Inventors: Newdoll, Ronald M., SHAVER, Argil E.
• Granted Patent: US 7,772,716 B2
• Time in Patent Office: Days
• US Class Current: 307/18
• CPC Class Codes: H01L 31/02021 for solar cells electrical connection means, e.g. junction boxes, specially adapted for structural association with photovoltaic modules H02S40/34
• CPC Class Codes: H02H 9/041 using a short-circuiting device
• 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 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: Y02A 30/60 Planning or developing urban green infrastructure
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

Distributed maximum power point tracking systems, structures, and processes are provided for power generation structures, such as for but not limited to a solar panel arrays. In an exemplary solar panel string structure, distributed maximum power point tracking (DMPPT) modules are provided, such as integrated into or retrofitted for each solar panel. The DMPPT modules provide panel level control for startup, operation, monitoring, and shutdown, and further provide flexible design and operation for strings of multiple panels. The strings are typically linked in parallel to a combiner box, and then toward and enhanced inverter module, which is typically connected to a power grid. Enhanced inverters are controllable either locally or remotely, wherein system status is readily determined, and operation of one or more sections of the system are readily controlled. The system provides increased operation time, and increased power production and efficiency, over a wide range of operating conditions.

Claims

1. A system, comprising:

a solar array, comprising

a plurality of solar panels each comprising a plurality of photovoltaic solar cells, and an associated panel DC outlet connection connected to the photovoltaic solar cells, and

a dedicated module comprising input connections that are connected to and locally powered by the associated panel DC outlet connection, and output connections that are connected to system DC bus, wherein each of the dedicated modules provides maximum power point tracking local to the respective solar panels;

an inverter module connected between the system DC bus and an AC bus;

a server; and

a communication link between the server and each of the dedicated modules.

2. The system of claim 1, further comprising:

at least one inverter housing;

wherein at least one of the inverter modules and the server are located within the inverter housing.

3. The system of claim 1, further comprising:

a microprocessor for feeding a signal to the inverter modules.

4. The system of claim 1, wherein the signal fed to the inverter modules comprises a pulse train signal.

5. The system of claim 4, wherein the pulse train signal reduces at least one harmonic in a DC signal processed at the inverters.

6. The system of claim 5, wherein the at least one harmonic comprises at least one third harmonic.

7. The system of claim 1, wherein the communication links between the server and each of the dedicated modules are any of wired communication links and wireless communication links.

8. A distributed maximum power point tracking system, the system comprising:

a plurality of power panels, each comprising a control module and a plurality of DC power cells connected to the control module, the control module comprising input connections, output connections, a signal processing circuit connected to the input connections and output connections, a communications interface, and module controller connected to the signal processing circuit and the communications interface

at least one inverter having input DC terminals, output AC terminals, and an inverter circuit connected to the input DC terminals, output AC terminals;

a server comprising means for communication to each of the module controllers over communications links to the communications interfaces, and means for feeding a signal to the inverter circuits.

9. The system of claim 8, wherein an output signal produced at least one of the signal processing circuits has a voltage that is higher than a voltage of an input signal provided by the respective power panels.

10. The system of claim 8, wherein the power panels comprise solar panels, fuel cells, or batteries.

11. The system of claim 8, further comprising:

at least one inverter housing;

wherein at least one of the inverters and the server are located within the inverter housing.

12. The system of claim 8, wherein the signal fed to the inverter circuits comprises a pulse train signal.

13. The system of claim 12, wherein the pulse train signal reduces at least one harmonic in a DC signal processed at the inverters.

14. The system of claim 13, wherein the at least one harmonic comprises at least one third harmonic.

15. The system of claim 8, wherein the communication links between the server and each of the control modules are any of wired communication links and wireless communication links.

16. An apparatus, comprising:

a direct current (DC) input bus connectable to a DC voltage source;

an output direct current (DC) voltage bus connectable to an inverter;

a signal processing circuit connected to the input DC bus and the output DC bus;

a controller connected to the signal processing circuit and having a communications interface; and

means for sending and receiving signals over the communications interface.

17. The apparatus of claim 16, wherein the DC voltage source is any of a photovoltaic solar panel, a fuel cell, and a battery.

18. The apparatus of claim 16, further comprising:

a crowbar circuit located across the input DC bus;

wherein the controller further comprises means for driving crowbar circuit to short across the input DC bus.

19. The apparatus of claim 16, further comprising:

means for resetting the crowbar circuit.

20. The apparatus of claim 19, wherein the means for resetting the crowbar circuit is controllable though the controller, through any of local logic or a communications signal received through the communications interface.

21. The apparatus of claim 19, wherein the means for resetting the crowbar circuit is provided internally by the module after a period of darkness.

22. The apparatus of claim 16, wherein the controller further comprises a temperature input.

23. A DMPPT process, comprising the steps of:

providing a module local to a DC voltage source having an input DC bus extending therefrom, the module comprising a controller locally powered from the input DC bus, and output connections connectable to an output DC bus, the module further comprising one or more control inputs;

powering up the module when the input voltage from the input DC bus reaches a threshold voltage;

processing the input voltage received from the input DC bus with the powered module to produce an output voltage higher than the input voltage; and

outputting the output voltage to the output DC bus through the output connections.

24. The process of claim 23, wherein the means for tracking the maximum power point of the panel comprises one or more control inputs, comprising any of input voltage, input current, output voltage, and output current.

25. The process of claim 23, wherein the module comprises a mechanism for receiving a signal responsive to a temperature of the DC voltage source.

26. The process of claim 25, wherein the controller is responsive to a received temperature signal from the DC voltage source.