Anomaly detection in inverter system

• US 7,486,082 B2
• Filed: 12/27/2006
• Issued: 02/03/2009
• Est. Priority Date: 07/22/2002
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Tanaka, Masaru, Hachisuka, Seiji, Senba, Minoru, Yadoori, Shuuichi
• Primary Examiner(s): Gutierrez; Diego
• Assistant Examiner(s): NATALINI, JEFF WILLIAM
• Application Number:
  US11/616,631
• Publication Number:
  US 20070103094A1
• Time in Patent Office: 769 Days
• Field of Search: 324/403, 324/536, 324/522
• US Class Current: 324/536
• CPC Class Codes: G01R 15/18 using inductive devices, e.g. transformers
• CPC Class Codes: G01R 31/42 AC power supplies
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: G01R 31/54 Testing for continuity
• CPC Class Codes: G09G 2330/04 Display protection
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H01F 38/30 Constructions
• CPC Class Codes: H02H 1/0007 concerning the detecting means in general G01R or other subclasses of G01; reed switches H01H71/2445
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 7/122 for inverters, i.e. dc/ac converters
• CPC Class Codes: H05B 41/2851 for protecting the circuit against abnormal operating conditions
• CPC Class Codes: H05B 41/2855 against abnormal lamp operating conditions

Abstract

An inverter system which converts DC input into AC output and supplies the AC output to a load such as an FL tube detects change in a circuit current due to anomaly such as discharge without contacting with a current route. Relating to an inverter which converts DC input into AC output and supplies the AC output to a load, change in a circuit current of the inverter is detected through the medium of magnetic flux change due to the change in the circuit current caused by discharge. For example, if change in a current occurs in the circuit current of the inverter by disconnection discharge or ground-fault discharge occurring in a current route including a load of the inverter, magnetic flux change occurs in circuit wiring and a space of a core gap of a transformer of the inverter. The change in the circuit current is detected through the medium of the magnetic flux change without contacting with the circuit wiring or the transformer.

Claims

1. An electronic device including an inverter, comprising:

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge in circuit wiring of said inverter or proximity discharge between high and low voltage parts of said circuit wiring; and

a control part that stops an operation of said inverter when said anomaly detection circuit detects the anomaly,

wherein said anomaly detection circuit includes a current detection part provided at a DC input side of said inverter, and

wherein said current detection part detects magnetic flux change occurring in the circuit wiring itself at the DC input side of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change.

2. An electronic device including an inverter, comprising:

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge of circuit wiring of said inverter or proximity discharge between high and low voltage parts of said circuit wiring;

a control part that stops an operation of said inverter when said anomaly detection circuit detects the anomaly;

a display driving part that generates a display driving output representative of the anomaly when said anomaly detection circuit detects the anomaly; and

an indicator that displays behavioral anomaly by the display driving output generated in said display driving part,

wherein said anomaly detection circuit includes a current detection part provided at a DC input side of said inverter, and

wherein said current detection part detects magnetic flux change, occurring in circuit wiring itself at the DC input side of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change.

3. A display device including an inverter, comprising:

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge of circuit wiring of said inverter or proximity discharge between high and low voltage parts of said circuit wiring; and

a control part that stops an operation of the inverter when said anomaly detection circuit detects the anomaly,

wherein said anomaly detection circuit includes a current detection part provided at a DC input side of said inverter, and

wherein said current detection part detects magnetic flux change, which occurring in circuit wiring itself at the DC input side of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change.

4. An information processing device including a display device, said display device comprising:

a fluorescent light tube lighting device including an inverter;

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge of circuit wiring of said inverter or proximity discharge between high and low voltage parts of said circuit wiring; and

a control part that stops an operation of the inverter when said anomaly detection circuit detects the anomaly,

wherein said anomaly detection circuit includes a current detection part provided at a DC input side of said inverter, and

wherein said current detection part detects magnetic flux change, occurring in circuit wiring itself at the DC input side of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change.

5. A lighting device including an inverter, comprising:

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge of circuit wiring of said inverter or ground-fault discharge; and

a control part that stops an operation of said inverter when said anomaly detection circuit detects the anomaly,

wherein said anomaly detection circuit includes a current detection part provided at a DC input side of said inverter, and

wherein said current detection part detects magnetic flux change, occurring in circuit wiring itself at the DC input side of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change.

6. An electronic device including an inverter, comprising:

an anomaly detection circuit that detects anomaly in which a current route is maintained by disconnection discharge in circuit wiring of said inverter or proximity discharge between high and low voltage parts of said circuit wiring; and

a control part that stops an operation of said inverter when said anomaly detection circuit detects the anomaly,

wherein said anomaly detection circuit includes a current detection part provided at a primary side and/or a secondary side of a transformer of said inverter,

wherein said current detection part detects magnetic flux change, which occurs in circuit wiring of said inverter, at the primary side and/or the secondary side of said transformer of said inverter by maintaining the current route caused by the disconnection discharge or the proximity discharge, and detects change in a circuit current of said inverter due to said discharge through the medium of the detected magnetic flux change, and

wherein said current detection part includes a detecting conductor that is arranged in the vicinity of said circuit wiring and is print-formed on a circuit board with said circuit wiring, and detects the magnetic flux change by said detecting conductor.