Source: http://www.google.com/patents/US7598748?ie=ISO-8859-1&dq=5,912,661
Timestamp: 2015-02-27 23:42:25
Document Index: 594370542

Matched Legal Cases: ['art 30', 'art 30', 'art 30', 'art 30', 'art 30', 'art 20', 'Application No. 03150194']

Patent US7598748 - Inverter system - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsAn 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...http://www.google.com/patents/US7598748?utm_source=gb-gplus-sharePatent US7598748 - Inverter systemAdvanced Patent SearchPublication numberUS7598748 B2Publication typeGrantApplication numberUS 10/620,597Publication dateOct 6, 2009Filing dateJul 17, 2003Priority dateJul 22, 2002Fee statusLapsedAlso published asCN1245634C, CN1475809A, DE60334053D1, EP1385360A1, EP1385360B1, US7486082, US7492162, US20040012381, US20070103094, US20070103163Publication number10620597, 620597, US 7598748 B2, US 7598748B2, US-B2-7598748, US7598748 B2, US7598748B2InventorsSeiji Hachisuka, Masaru Tanaka, Minoru Senba, Shuuichi YadooriOriginal AssigneeFujitsu LimitedExport CitationBiBTeX, EndNote, RefManPatent Citations (34), Non-Patent Citations (12), Referenced by (3), Classifications (29), Legal Events (4) External Links: USPTO, USPTO Assignment, EspacenetInverter system
US 7598748 B2Abstract
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.
1. A current detection method of an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
allowing magnetic flux change occurring to a circuit wiring to act on a detecting conductor arranged in the vicinity of the circuit wiring, the magnetic flux change occurring because of a change in a circuit current due to discharge, both the detecting conductor and the circuit wiring being printed on a same side of a circuit board, the detecting conductor having a straight-line segment disposed parallel to a straight-line segment of the circuit wiring such that the magnetic flux change that occurs to the circuit wiring is allowed to act on the straight-line segment of the detecting conductor; and
detecting the change in the circuit current through the medium of the magnetic flux change by the detecting conductor.
2. The current detection method of claim 1, further comprising:
rectifying and smoothing a current detected by the detecting conductor by acting of the magnetic flux change occurring to the circuit wiring; and
taking out a detection signal at a level representative of the change in the circuit current.
3. An anomaly detection method of an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
detecting the change in the circuit current through the medium of the magnetic flux change by the detecting conductor so as to detect based on a result of the detecting of the change in the circuit current whether or not anomaly exists in a current route including the load.
4. The anomaly detection method of claim 3, further comprising:
5. A test method using an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
detecting the change in the circuit current through the medium of the magnetic flux change by the detecting conductor so as to decide based on a result of the detecting of the change in the circuit current whether or not anomaly exists in a current route including the load.
6. The test method of claim 5, further comprising:
7. A current detection method, comprising:
allowing a magnetic flux change produced by a circuit current flowing through a circuit wiring to act on a detecting conductor located in a vicinity of the circuit wiring, both the detecting conductor and the circuit wiring being printed on a same side of a circuit board, the detecting conductor having a straight-line segment disposed parallel to a straight-line segment of the circuit wiring such that the magnetic flux change that occurs to the circuit wiring is allowed to act on the straight-line segment of the detecting conductor; and
detecting the change in the circuit current through the medium of the magnetic flux change on the detecting conductor.
8. The current detection method of claim 7, further comprising:
The present invention relates to an inverter for converting DC input into AC output so as to feed the AC output to a load such as an FL tube and so forth, and it is an object of the invention to detect change in a circuit current caused by discharge with ease, without contacting with a current route.
If disconnection discharge occurring in a current route including a load of the inverter or proximity discharge namely ground-fault discharge between high voltage and low voltage parts of a circuit wiring arise, current change occurs in a circuit current of the inverter, and that change makes magnetic flux change occur at a circuit wiring and at a space of a core gap of a transformer. Therefore, if the change-in the circuit current is detected through the medium of the magnetic flux change, the change in the circuit current can be detected without contacting with the circuit wiring and the transformer. By this, it is possible to know anomaly such as discharge occurring in the current route from that change.
(1) Display of behavioral anomaly such as disconnection discharge and ground-fault discharge, (2) Display of stop of the inverter operation, (3) Display of either (1) or (2) or both (1) and (2). It is possible to easily detect behavioral anomaly and the stop of the inverter operation from these displays so that necessary measures can be taken as soon as practicable.
In order to attain the above objects, an electronics device such as an information processing device according to the present invention is a construction that provides the current detection circuit of the inverter, the anomaly detection circuit of the inverter, or the display device. According to an information processing device like this, a lighting device for driving an illumination load such as a discharge tube and so forth and a power supply system such as a power supply circuit and so forth can be constructed using the inverter of the present invention. Further, if the information processing device is constructed using the current detection circuit and/or the anomaly detection circuit of such an inverter, behavioral anomaly such as disconnection discharge and ground-fault discharge can be discovered, or continuation of behavioral anomaly can be avoided, the display of behavioral anomaly or the display of the stop of inverter operation can be displayed, and also confirmation of an operating condition can be performed with ease, thereby facilitating the protection of the display device of the information processing side. Still further, a reliability of a power supply device of various circuits can be enhanced, and the information processing device can be protected from continuation of behavioral anomaly of a power supply system, thereby contributing to a reliability of the operation.
An embodiment of a current detection method of an inverter, a current detection circuit thereof, an anomaly detection method thereof and an anomaly detection circuit thereof according to the present invention is explained by referring to FIG. 1. FIG. 1 shows an FL tube lighting device according to an embodiment of the present invention. The FL tube lighting device constitutes an FL tube lighting device used as a backlight of a liquid crystal display (LCD).
The current detection part 30 is a circuit part which detects a change in the circuit current through the medium of a magnetic flux change cased by the change in the circuit current from the circuit wiring 16 of the inverter 2, and so on. In this embodiment, the circuit wiring 16 side of the inverter 2, which is a lower potential side thereof, is set as a current detection point. In the current detection part 30, a current detection line 36 is provided as a detecting conductor which detects the change in the circuit current through the medium of a magnetic flux change Δφ that occurs to the circuit wiring 16. In this case, DC input current id is a detection target in connection with the change in circuit current, to be detected. The current detection line 36 is arranged in the vicinity of the circuit wiring 16, and at such a spacing therefrom as allowing the magnetic flux change Δφ occurring thereto to be detected.
Next, the current detection part 30 is explained by referring to FIG. 2. FIG. 2 shows an example of the current detection part 30. The current detection part 30 is constituted by the current detection line 36 having the same wiring pattern as the circuit wiring 16 provided on a printed circuit board 38, and, in this embodiment, the wiring patterns of the circuit wiring 16 and the current detection line 36 constitutes parallel patterns. That is, the current detection line 36 having a straight-line segment parallel with the circuit wiring 16 in a straight-line form is disposed, and the magnetic flux change Δφ occurring to the circuit wiring 16 due to a change in the DC input current id is caused to act on the current detection line 36. In this case, a reference letter �a� is width of the current detection line 36, a reference letter �b� is length of the current detection line 36, and a predetermined insulating spacing D is set between the current detection-line 36 and the circuit wiring 16. Sensitivity in detection of the magnetic flux change Δφ is enhanced by rendering the insulating spacing D narrower.
Further, if the current detection line 36 is arranged in the vicinity of the circuit wiring 54, the change in an output current i2 can be detected through the medium of the magnetic flux change Δφ caused by the change in the output current i2 which is the secondary current of the inverter transformer 22 flowing through the circuit wiring 54, and the inverter operation can be stopped at the time of behavioral anomaly, and hence an inverter 2, an FL tube 4 and so forth can be protected from continuation of behavioral anomaly such as discharge and so forth. In this case, the change in a wave form is larger at the output side of the inverter transformer 22 compared with that at the input side thereof, and also the change value of the discharge waveform is remarkably increased. Because of this, a circuit current change and a magnetic flux change are larger, and the accuracy of detection is enhanced.
Referring to the flow diagram shown in FIG. 13, if the test is started, whether or not the FL tube 4 is connected to the test device 96 is decided (a step S11), and the supply of a power source to the FL tube 4 from the inverter 2 is started if the FL tube 4 is connected (a step S12). As a result of the supply of the power source, whether or not change in a circuit current is more than a predetermined level is decided (a step S13). If disconnection discharge or ground-fault discharge does not occur in a current route of the side of the FL tube 4 which is a load, the change in the circuit current due to its discharge current does not occur, and the change in the circuit current becomes under the predetermined level. The detection of this change in the circuit current is as described before. In this case, a detected output of the anomaly detection circuit 6 is given to the processor 78 from a comparator 34, the processor 78 decides that the unit 92 is a normal condition, and a result of that decision representative of the normal condition is displayed as a test result on the display 98 (a step S14). On the other hand, if the disconnection discharge or the ground-fault discharge occurs in the current route of the side of the FL tube 4 which is a load, great change in the circuit current occurs by its discharge current, and that change becomes above the predetermined level. The detection of this change in the circuit current is as described before. In this case, the detected output of the anomaly detection circuit 6 is given to the inverter control part 20, and an inverter output is stopped. At the same time, the detected output is given to the processor 78 from the comparator 34, the processor 78 decides that the unit 92 is an anomalous condition, and a result of that decision representative of the anomalous condition is displayed as a test result on the display 98 (a step S15). Then, after stopping the supply of the power source (a step S16), the liquid crystal display unit 92 which has finished the test is taken off from the test device 96, a next liquid crystal display unit 92 is connected to the test device 96, and the same test is performed.
The entire disclosure of Japanese Patent Applications No. 2002-212666 and No. 2003-183034 including specifications, claims, drawings and summaries are incorporated herein by reference in their entirety.
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No. 11/616,631.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS7834562 *Oct 23, 2006Nov 16, 2010Minebea Co., Ltd.Discharge lamp lighting deviceUS8000912 *Dec 12, 2008Aug 16, 2011Ls Industrial Systems Co., Ltd.Instrument transformer and apparatus for detecting an amount of power using the sameUS8837094Mar 16, 2011Sep 16, 2014Nlt Technologies, Ltd.DC/AC inverter substrate having voltage abnormality detector circuit* Cited by examinerClassifications U.S. Classification324/522, 324/750.02, 324/529International ClassificationH05B41/285, H02H1/00, H01F38/30, H02M7/48, H05B41/24, G01R29/08, G01R19/165, H02H7/122, G01R19/20Cooperative ClassificationH01F38/30, G09G3/3406, G01R15/18, G01R31/42, G01R31/026, H05B41/2851, G09G2330/04, H02H7/122, H05B41/2855, G09G3/006, H02H1/0015, H02H1/0007European ClassificationG01R15/18, G01R31/42, H02H1/00C, H05B41/285C4, H05B41/285CLegal EventsDateCodeEventDescriptionNov 26, 2013FPExpired due to failure to pay maintenance feeEffective date: 20131006Oct 6, 2013LAPSLapse for failure to pay maintenance feesMay 17, 2013REMIMaintenance fee reminder mailedJul 17, 2003ASAssignmentOwner name: FUJITSU LIMITED, JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HACHISUKA, SEIJI;TANAKA, MASARU;SENBA, MINORU;AND OTHERS;REEL/FRAME:014299/0219Effective date: 20030707RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services