Photovoltaic string reverse polarity detection

• US 10,404,060 B2
• Filed: 02/22/2016
• Issued: 09/03/2019
• Est. Priority Date: 02/22/2015
• Status: Active Grant

• Current Assignee: Marici Holdings The Netherlands B.V.
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: White, Paul M.
• Primary Examiner(s): Nguyen, Hoa C
• Assistant Examiner(s): DePew, Keith
• Application Number:
  US15/552,088
• Publication Number:
  US 20180048146A1
• Time in Patent Office: 1,289 Days
• CPC Class Codes: H01H 85/05 Component parts thereof
• CPC Class Codes: H02H 11/002 in case of inverted polarity or connection; with switching for obtaining correct connection
• CPC Class Codes: H02S 50/00 Monitoring or testing of PV systems, e.g. load balancing or fault identification
• CPC Class Codes: H02S 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

One or more techniques and/or systems are provided for detecting reverse polarity of a photovoltaic system. A fuse holder may comprise a fuse holder body configured to receive a fuse used to protect against excessive current from a photovoltaic string of the photovoltaic system, such as current from a short circuit due to the photovoltaic string being installed backwards and having a reverse polarity. Because installation of the fuse while the photovoltaic string has reverse polarity may result in substantial damage and harm, a reverse polarity detection component may be configured to identify the reverse polarity and provide a warning of the reverse polarity before the fuse is installed (e.g., an audible alert, a blinking light, a locking of the fuse holder to prohibit installation of the fuse, etc.).

Claims

1. A system for detecting reverse polarity of a photovoltaic system, comprising:

a fuse holder comprising;

a fuse holder body configured to receive a fuse;

a reverse polarity detection component configured to identify a polarity of a photovoltaic string of a photovoltaic arrangement and, responsive to the polarity being indicative of a reverse polarity, to provide a reverse polarity indication of the reverse polarity; and

a locking mechanism for locking the fuse holder body to prohibit installation of the fuse responsive to the polarity being indicative of the reverse polarity.

2. The system of claim 1, the locking mechanism comprising a solenoid.

3. The system of claim 1, the fuse holder comprising a first indicator light and a second indicator light, and the reverse polarity detection component configured to:

responsive to the polarity being indicative of the reverse polarity, provide the reverse polarity indication through the first indicator light; and

responsive to the polarity being indicative of a normal polarity, provide a normal polarity indication through the second indicator light.

4. The system of claim 1, the reverse polarity detection component configured to provide the reverse polarity indication as an audible alert.

5. The system of claim 1, the fuse holder body configured to withstand double a rated voltage of the fuse.

6. The system of claim 1, the fuse holder body configured to provide galvanic isolation between a fuse holder body input and a fuse holder body output of the fuse holder body when the fuse holder body is in an open position.

7. The system of claim 1, the reverse polarity detection component configured to detect reverse polarity when the fuse is not installed within the fuse holder body.

8. The system of claim 1, the reverse polarity detection component configured to bypass reverse polarity detection when the fuse is installed within the fuse holder body.

9. The system of claim 1, the fuse having a rating corresponding to an open circuit voltage of the photovoltaic arrangement.

10. The system of claim 1, comprising:

a photovoltaic string combiner configured to combine a set of photovoltaic strings of the photovoltaic arrangement, the photovoltaic string combiner comprising;

a fuse holder installation arrangement configured to receive the fuse holder for installation.

11. The system of claim 10, the photovoltaic string combiner comprising a DC power output connection to an inverter, the inverter configured to convert DC power, provided by the photovoltaic arrangement through the photovoltaic string combiner, to AC power.

12. The system of claim 1, the fuse holder configured to function as a blown fuse indicator for the photovoltaic string when the fuse is installed within the fuse holder.

13. A system for detecting reverse polarity of a photovoltaic system, comprising:

a reverse polarity detection component configured to;

identify a polarity of a photovoltaic string of a photovoltaic arrangement, the photovoltaic string configured to connect to a fuse holder comprising a fuse holder body configured to receive a fuse for the photovoltaic string;

responsive to the polarity being indicative of a reverse polarity, provide a reverse polarity indication of the reverse polarity; and

invoke a locking mechanism to lock the fuse holder body to prohibit installation of the fuse responsive to the photovoltaic string being indicative of the reverse polarity.

14. The system of claim 13, the reverse polarity detection component comprising a first indicator light and a second indicator light, the reverse polarity detection component configured to:

responsive to the polarity being indicative of the reverse polarity, provide the reverse polarity indication through the first indicator light; and

responsive to the polarity being indicative of a normal polarity, provide a normal polarity indication through the second indicator light.

15. The system of claim 13, the reverse polarity detection component configured to provide the reverse polarity indication as an audible alert.

16. A system for detecting reverse polarity of a direct current system, comprising:

a fuse holder comprising;

a fuse holder body configured to receive a fuse;

a reverse polarity detection component configured to identify a polarity of a direct current source and, responsive to the polarity being indicative of a reverse polarity, to provide a reverse polarity indication of the reverse polarity; and

a locking mechanism configured to lock the fuse holder body to prohibit installation of the fuse responsive to the polarity being indicative of the reverse polarity.

17. The system of claim 16, the direct current source comprising one or more photovoltaic panels.

18. The system of claim 16, wherein the fuse holder further comprises a light element for providing the reverse polarity indication as visible illumination.

19. The system of claim 16, wherein the fuse holder further comprises a speaker for providing the reverse polarity indication as an audible alert.