Source: http://www.google.com/patents/US7492162?ie=ISO-8859-1&dq=5,666,293
Timestamp: 2014-07-13 05:56:09
Document Index: 448450456

Matched Legal Cases: ['art.\n2', 'art 20', 'art 20', 'art 20', 'art 20', 'art 20', 'art 20', 'art 20', 'Application No. 03150194']

Patent US7492162 - Inverter system - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign in<nobr>Advanced Patent Search</nobr>PatentsAn 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/US7492162?utm_source=gb-gplus-sharePatent US7492162 - Inverter systemAdvanced Patent SearchPublication numberUS7492162 B2Publication typeGrantApplication numberUS 11/616,623Publication dateFeb 17, 2009Filing dateDec 27, 2006Priority dateJul 22, 2002Fee statusLapsedAlso published asCN1245634C, CN1475809A, DE60334053D1, EP1385360A1, EP1385360B1, US7486082, US7598748, US20040012381, US20070103094, US20070103163Publication number11616623, 616623, US 7492162 B2, US 7492162B2, US-B2-7492162, US7492162 B2, US7492162B2InventorsSeiji Hachisuka, Masaru Tanaka, Minoru Senba, Shuuichi YadooriOriginal AssigneeFujitsu LimitedExport CitationBiBTeX, EndNote, RefManPatent Citations (30), Non-Patent Citations (9), Referenced by (1), Classifications (26), Legal Events (3) External Links: USPTO, USPTO Assignment, EspacenetInverter systemUS 7492162 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 circuit of an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
a current detection part, provided at the DC input side of said inverter, that detects magnetic flux change, which occurs in a portion of circuit wiring passing through the current detection part of said inverter based on a change in a circuit current due to discharge occurring in the overall circuit wiring of said inverter, at the DC input side of said inverter, said current detection part detecting the change in the circuit current through the medium of the magnetic flux change; and
a current change detection part that inputs a detected output of the current detection part and detects current change, the current change detection part including a rectification part that rectifies a fluctuation voltage obtained by the magnetic flux change and a smoothing part that smoothes a rectified voltage given from said rectification part.
2. The current detection circuit of claim 1, further comprising:
a detecting conductor that is provided adjacent to said portion of circuit wiring, wherein
the detecting conductor detects the magnetic flux change occurring in said portion of the circuit wiring.
3. The current detection part of claim 2, wherein said current detection part constitutes said detecting conductor and a portion of said circuit wiring as an independent discrete element.
4. The current detection circuit of claim 2 further comprising a core that forms a common magnetic path for said circuit wiring and said detecting conductor.
5. The current detection circuit of claim 1, wherein said rectification part is constituted by Schottky diode.
6. The current detection circuit of claim 1, wherein said current change detection part includes a filter that extracts change in a current due to discharge including disconnection discharge and dielectric breakdown discharge.
7. A current detection circuit of an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
a current detection part that detects magnetic flux change occurring based on a change in a circuit current of said inverter due to discharge that occurs in circuit wiring of the inverter, said current detection part detecting the change in the circuit current through the medium of the detected magnetic flux change; and
a current change detection part that inputs a detected output of the current detection part and detects current change, the current change detection part including a rectification part that rectifies a fluctuation voltage obtained by the magnetic flux change and a smoothing part that smoothes a rectified voltage given from said rectification part, wherein
a core of a transformer of said inverter has a gap formed in a magnetic path, and
said current detection part includes a detecting conductor provided at a space of the gap of the core of said transformer, and detects the magnetic flux change occurring at the space of the gap of the core of said transformer by said detecting conductor.
8. A current detection circuit of an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
a current detection part, provided at a primary side and/or a secondary side of a transformer of said inverter, detecting magnetic flux change, which occurs in a portion of circuit wiring passing through the current detection part of said inverter based on a change in a circuit current due to discharge occurring in the overall circuit wiring of said inverter, said current detection part detecting the change in the circuit current through the medium of the magnetic flux change; and
a current change detection part that inputs a detected output of the current detection part and detects current change, the current change detection part including a rectification part that rectifies a fluctuation voltage obtained by the magnetic flux change and a smoothing part that smoothes a rectified voltage given from said rectification part,
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.
9. A test method using an inverter that converts DC input into AC output and supplies the AC output to a load, comprising:
a step that, by a current detection part, detects magnetic flux change, which occurs in a portion of circuit wiring at the DC input side of said inverter based on a change in a circuit current due to discharge occurring in the overall circuit wiring of said inverter, and detects the change in the circuit current through the medium of the magnetic flux change;
a step that inputs a detected output of the current detection part to a current change detection part and outputs the detected output of the current detection part as a result of a detection, the current change detection part including a rectification part that rectifies a fluctuation voltage obtained by the magnetic flux change and a smoothing part that smoothes a rectified voltage given from said rectification part; and
a step that decides based on the result of the detection of the change in said circuit current whether or not anomaly exists in a current route including said load.
10. A current detection circuit comprising:
a current detection part, provided at a DC input side of an inverter, that detects magnetic flux change occurring in a portion of circuit wiring at the DC input side of said inverter based on a change in a circuit current due to discharge occurring in the overall circuit wiring of said inverter; and
a current change detection part that inputs a detected output of the current detection part and detects current change, the current change detection part including a rectification part that rectifies a fluctuation voltage obtained by the magnetic flux change and a smoothing part that smoothes a rectified voltage given from said rectification part. Description
CROSS REFERENCE TO RELATED APPLICATION This application is a Divisional of application Ser. No. 10/620,597 entitled INVERTER SYSTEM, filed Jul. 17, 2003, now pending, the entire contents of which are incorporated by reference herein. This application also claims priority to Japanese Application Nos. 2002-212666 & 2003-183034 filed Jul. 22, 2002 and Jun. 26, 2003, respectively, also incorporated by reference herein.
According to the Publication No. 6-140173, as a protecting device for a discharge lamp lighting system, even if a discharge lamp is lit out at the time of anomaly, inconvenience to maintain the operation of a transistor inverter is avoided wherein an output of the inverter is taken out to monitor an oscillation condition by a monitor circuit, and anomaly occurring at the oscillation condition due to a short circuit inside the discharge lamp and so forth is detected by a monitoring pulse voltage so as to stop the operation of the inverter by stopping the feed of a DC voltage, and light out the discharge lamp. However, such a protection device is complex in configuration because it requires the monitor circuit for taking out the output of the inverter and monitoring thereof, a microcomputer for determining whether the monitoring pulse voltage is normal or anomalous, and so forth, and also since the output of the inverter is taken out to an outside, the inverter side is forced to take measures to cope with the change in an operating condition.
The inverter 2 has DC input terminals 8, 10 for receiving DC input and the DC input terminals 8, 10 are connected to a DC power source 12 from which DC input to be converted into AC output is fed. The DC power source 12 includes various DC power sources such as a battery, an AC-DC converter, and so forth. Circuit wirings 14, 16 are connected to the DC input terminals 8, 10 so as to form a current route of a DC input current and an input smoothing capacitor 18 is connected to the circuit wirings 14, 16. The circuit wirings 14, 16 are formed of, for example, a conductor pattern on a printed circuit board, and the input smoothing capacitor 18 constitutes a filter for removing fluctuation component of a voltage ripple and the like included in the DC input and smoothes out a fluctuating DC input so as to stabilize it. The DC input is fed to an inverter control part 20 through the DC input terminals 8, 10 and the circuit wirings 14, 16. The inverter control part 20 comprises, for example, not shown, push-pull inverter circuit part formed of multiple transistors serving as switching elements, a drive circuit part, a switching controller, and so forth, and it also constitutes an oscillation circuit including a primary winding 24 of an inverter transformer 22 and so on in a feedback circuit. In this embodiment, the inverter control part 20 incorporates a switch 26 for switching supply of power to the circuit wiring 14. The switch 26 switches over supply of power from outside on the basis of a control input fed to a latch input terminal 28 serving as a control input part of the inverter control part 20. A known device such as a general-purpose control IC (TI, TL5001, and so forth) which is already available in a market can be used as the inverter control part 20, and hence a detailed circuit configuration is omitted.
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 waveform 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.
An inverter transformer 22 used in the inverter 2 has a gap 25 which is formed in a core 23, and is provided so that the gap 25 is positioned in the side of a printed circuit board 38. Therefore, a current detection line 36 is provided on the printed circuit board 38 at a space of the gap 25 by means of a wiring pattern. In other words, the current detection line 36 which has width �a� narrower than a space �w� of the core 23 and length �b� is formed on the printed circuit board 38, the core 23 of the inverter transformer 22 is provided astride of the printed circuit board 38, and the current detection line 36 is arranged in the space of the gap 25. Although the length �b� of the current detection line 36 is set larger than width �d� of the core 23, it may also be set to the same length (b=d) . Further, to the inverter transformer 22, a primary winding 24 and a secondary winding 50 are provided. Terminals 24 a and 24 b of the primary winding 24 are connected to the inverter control part 20, one terminal 50 a of the secondary winding 50 is connected to the ballast capacitor 56 (FIG. 1) , and the other terminal 50 b is connected to the constant current detection resistor 60.
At the time of the normal condition, it is displayed on the LCD 64 or the indicator 76 that behavioral anomaly does not exist, namely, a normal behavior is performed (a step S3). When a predetermined time elapses from the start of the display of the normal behavior or an administrator instructs an operation display cancel from the keyboard 80, the display operation is cancelled (a step S4) , and, after that, the processing is returned to the step S1.
When behavioral anomaly is detected in the step S2, the behavioral anomaly is displayed on the LCD 64 or the indicator 76 and the stop of operation of the inverter 2 is displayed on the same (a step S5). The administrator verifies these displays, and executes necessary processing. For example, when a predetermined time elapses from the start of the display of behavioral anomaly or the administrator instructs an operation display cancel from the keyboard 80, the display cancel is effected (a step S6) , and, after that, the processing is returned to the step S1. In this case, when behavioral anomaly is displayed, the display cancel may not be effected unless the administrator effects an improvement processing.
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 descried 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.
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No. 11/616,631.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS8742787Feb 5, 2010Jun 3, 2014Valeo Systemes ThermiquesMethod for detecting a short-circuit, and power supply module implementing said methodClassifications U.S. Classification324/522International ClassificationH02M7/48, H01F38/30, G01R19/165, H02H1/00, H02H7/122, H05B41/285, H05B41/24, G01R31/08Cooperative ClassificationG01R31/42, G09G3/3406, G09G3/006, G09G2330/04, G01R15/18, H01F38/30, H05B41/2855, H02H1/0007, H02H7/122, G01R31/026, H02H1/0015, H05B41/2851European ClassificationH02H1/00C, H05B41/285C4, H05B41/285C, G01R31/42, G01R15/18Legal EventsDateCodeEventDescriptionApr 9, 2013FPExpired due to failure to pay maintenance feeEffective date: 20130217Feb 17, 2013LAPSLapse for failure to pay maintenance feesOct 1, 2012REMIMaintenance fee reminder mailedRotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google