CN103558521A - Device for detecting partial discharge of transformer under surge voltage - Google Patents
Device for detecting partial discharge of transformer under surge voltage Download PDFInfo
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- CN103558521A CN103558521A CN201310532330.0A CN201310532330A CN103558521A CN 103558521 A CN103558521 A CN 103558521A CN 201310532330 A CN201310532330 A CN 201310532330A CN 103558521 A CN103558521 A CN 103558521A
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Abstract
The invention discloses a device for detecting the partial discharge of a transformer under a surge voltage, wherein the device solves the problem that partial discharge detection on the transformer under the surge voltage is difficult to conduct on site. According to the device, a standard capacitive voltage divider (2) is connected between the output end of a surge voltage generator (1) and the ground, the output end of the surge voltage generator is electrically connected with a winding of the transformer (5) through a transformer high-voltage bushing (4), a first high-frequency current sensor (8) is connected to a bushing end screen grounding lead (6) of the transformer high-voltage bushing in a sleeved mode, the first high-frequency current sensor is connected with one input end of a high-pass filter (11), a second high-frequency current sensor (9) is connected to a body grounding lead (7) of the transformer in a sleeved mode, the second high-frequency current sensor is connected with the other input end of the high-pass filter, and the output end of the high-pass filter is connected with a high-speed oscilloscope (12). The device for detecting the partial discharge of the transformer under the surge voltage has great significance in failure diagnosis and state evaluation of the transformer.
Description
Technical field
The present invention relates to a kind of experiment detection device of electrical equipment, the device particularly under a kind of surge voltage, partial discharge of transformer being detected.
Background technology
Power transformer is one of visual plant in electrical network, and its safe operation is being related to the safety of whole electrical network.To power transformer, to carry out impulse voltage test, power-frequency voltage test and power-frequency voltage and merge partial discharge test.Power-frequency voltage wherein merges partial discharge test and in long-term enforcement, has obtained everybody approval, thinks the effective means that can transformer fault be tested and be diagnosed.Impulse voltage test wherein, at present, also just carries out withstand voltage test, does not carry out the experimental measurement of shelf depreciation under surge voltage.But when transformer is carried out to impulse voltage test, carry out measurement of partial discharge, can effectively improve the sensitivity of transformer fault diagnosis, for the degree of injury of judgment device, have great importance.The patent No. is 201220536097.4, the Chinese patent that exercise question is " under a kind of surge voltage based on bipolar electrode in transformer oil the pick-up unit of point discharge " discloses a kind of pick-up unit, this device in impulse voltage generator, capacitive divider, transformer oil in point electrode, transformer oil slightly the parts such as nonuniform field electrode, current sensor, transmission cable, Hi-pass filter, oscillograph form, can impact voltage under in transformer oil point discharge test and study.But the detected object of this device is a defect experimental considerations unit, not for entity transformer, under carrying out surge voltage, during the detection of entity partial discharge of transformer, the bipolar electrode method that this patent provides cannot be implemented ready-made.Therefore, carry electricity on-the-spot pick-up unit and detection method in the urgent need to shelf depreciation under a kind of simple, practical and effective transformer surge voltage.
Summary of the invention
The invention provides partial discharge of transformer pick-up unit under a kind of surge voltage, solved and at the scene transformer has been implemented to the difficult problem that surge voltage is carried out Partial Discharge Detection.
The present invention solves above technical matters by the following technical programs:
Partial discharge of transformer pick-up unit under a kind of surge voltage, comprise impulse voltage generator, standard capacitor divider, transformer and high-speed oscilloscope, between the output terminal of impulse voltage generator and ground, be connected with standard capacitor divider, the output terminal of impulse voltage generator links together by the winding electric of transformer high-voltage bushing and transformer, on the bottom shielding of bushing ground lead of transformer high-voltage bushing, be socketed with the first High Frequency Current Sensor, the first High Frequency Current Sensor is connected with the input end of Hi-pass filter, on the body ground lead of transformer, be socketed with the second High Frequency Current Sensor, the second High Frequency Current Sensor is connected with another input end of Hi-pass filter, the output terminal of Hi-pass filter is connected with high-speed oscilloscope, the middle part output terminal of standard capacitor divider is connected with high-speed oscilloscope by signal wire.
The intrinsic standoff ratio of standard capacitor divider is 1000:1.
Under a partial discharge of transformer detection method, comprise the following steps:
The first step, connection standard capacitive divider between the output terminal of impulse voltage generator and ground, the output terminal of impulse voltage generator is connected with the winding electric of transformer by transformer high-voltage bushing, on the bottom shielding of bushing ground lead of transformer high-voltage bushing, be socketed the first High Frequency Current Sensor, the first High Frequency Current Sensor is connected with the input end of Hi-pass filter, on the body ground lead of transformer, be socketed the second High Frequency Current Sensor, the second High Frequency Current Sensor is connected with another input end of Hi-pass filter, the output terminal of Hi-pass filter is connected with high-speed oscilloscope, the middle part output terminal of standard capacitor divider is connected with high-speed oscilloscope by signal wire,
Second step, impulse voltage generator produce a low amplitude value surge voltage, the amplitude maximal value of this low amplitude value surge voltage is less than 50% of trial voltage, if now transformer is interior without local discharge signal, the current pulse signal in the first High Frequency Current Sensor that high-speed oscilloscope is collected and the current pulse signal in the second High Frequency Current Sensor be reference signal as a setting;
The 3rd step, impulse voltage generator produce a surge voltage, the amplitude maximal value of this surge voltage equals 100% of trial voltage, high-speed oscilloscope gathers current pulse signal in the first High Frequency Current Sensor and the current pulse signal in the second High Frequency Current Sensor, the two reference background signals that these two current pulse signals and second step are obtained compare, if there is aobvious discharge pulse, there is shelf depreciation in transformer;
The polarity of current pulse signal and the polarity of the current pulse signal in the second High Frequency Current Sensor in the 4th step, the first High Frequency Current Sensor that the 3rd step high speed oscillograph is collected compare, if bipolarity is identical, discharge pulse is produced by transformer external circuit, if bipolarity is contrary, discharge pulse is produced by transformer itself.
The present invention carries out the detection of partial discharge of transformer under surge voltage, simple in structure, easy to operate, for production scene, transformer being carried out to partial discharge test provides attainable pick-up unit and method, significant to fault judgement and the state estimation of transformer.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention;
Fig. 2 is the process flow diagram of testing process of the present invention;
Fig. 3 is pulsed current signal polarity and the schematic diagram of the pulsed current signal polarity in sleeve pipe equivalent capacity when transformer does not produce shelf depreciation in the transformer equivalent capacity that collects of high-speed oscilloscope 12 of the present invention;
Fig. 4 is pulsed current signal polarity and the schematic diagram of the pulsed current signal polarity in sleeve pipe equivalent capacity when transformer produces shelf depreciation in the transformer equivalent capacity that collects of high-speed oscilloscope 12 of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in detail:
Partial discharge of transformer pick-up unit under a kind of surge voltage, comprise impulse voltage generator 1, standard capacitor divider 2, transformer 5 and high-speed oscilloscope 12, between the output terminal of impulse voltage generator 1 and ground, be connected with standard capacitor divider 2, the output terminal of impulse voltage generator 1 links together by transformer high-voltage bushing 4 and the winding electric of transformer 5, on the bottom shielding of bushing ground lead 6 of transformer high-voltage bushing 4, be socketed with the first High Frequency Current Sensor 8, the first High Frequency Current Sensor 8 is connected with the input end of Hi-pass filter 11, on the body ground lead 7 of transformer 5, be socketed with the second High Frequency Current Sensor 9, the second High Frequency Current Sensor 9 is connected with another input end of Hi-pass filter 11, the output terminal of Hi-pass filter 11 is connected with high-speed oscilloscope 12, the middle part output terminal of standard capacitor divider 2 is connected with high-speed oscilloscope 12 by signal wire 10.
Under a partial discharge of transformer detection method, comprise the following steps:
The first step, connection standard capacitive divider 2 between the output terminal of impulse voltage generator 1 and ground, the output terminal of impulse voltage generator 1 is connected with the winding electric of transformer 5 by transformer high-voltage bushing 4, on the bottom shielding of bushing ground lead 6 of transformer high-voltage bushing 4, be socketed the first High Frequency Current Sensor 8, the first High Frequency Current Sensor 8 is connected with the input end of Hi-pass filter 11, on the body ground lead 7 of transformer 5, be socketed the second High Frequency Current Sensor 9, the second High Frequency Current Sensor 9 is connected with another input end of Hi-pass filter 11, the output terminal of Hi-pass filter 11 is connected with high-speed oscilloscope 12, the middle part output terminal of standard capacitor divider 2 is connected with high-speed oscilloscope 12 by signal wire 10,
Second step, impulse voltage generator 1 produce a low amplitude value surge voltage, the amplitude maximal value of this low amplitude value surge voltage is less than 50% of trial voltage, if now transformer is interior without local discharge signal, the current pulse signal in the first High Frequency Current Sensor 8 that high-speed oscilloscope 12 is collected and the current pulse signal in the second High Frequency Current Sensor 9 be reference signal as a setting;
The 3rd step, impulse voltage generator 1 produce a surge voltage, the amplitude maximal value of this surge voltage equals 100% of trial voltage, current pulse signal in high-speed oscilloscope 12 collection the first High Frequency Current Sensor 8 and the current pulse signal in the second High Frequency Current Sensor 9, the two reference background signals that these two current pulse signals and second step are obtained compare, if there is aobvious discharge pulse, there is shelf depreciation in transformer;
The polarity of current pulse signal and the polarity of the current pulse signal in the second High Frequency Current Sensor 9 in the 4th step, the first High Frequency Current Sensor 8 that the 3rd step high speed oscillograph 12 is collected compare, if bipolarity is identical, discharge pulse is produced by transformer external circuit, if bipolarity is contrary, discharge pulse is produced by transformer itself.
The present invention adopts impulse voltage generator 1 as the trial voltage of transformer, and High Voltage Impulse Waveform is standard lightning impulse, standard switching impulse voltage, oscillation mode lightning impulse and four kinds of High Voltage Impulse Waveforms of oscillation mode switching impulse.High Voltage Impulse Waveform is applied in Transformer Winding by sleeve pipe, when needs are tested high pressure winding, can surge voltage be applied on high pressure winding by bushing 4, equally, but in the time of need to testing voltage winding, can surge voltage be applied on low pressure winding by low-tension bushing 3.
Adopt standard capacitor divider 2 to carry out the acquisition of trial voltage waveform, capacitive divider intrinsic standoff ratio is 1000:1.
The first High Frequency Current Sensor 8 and the second High Frequency Current Sensor 9 that on the ground wire of bottom shielding of bushing and transformer body ground wire, are socketed all adopt this lubber ring of Kenneth Rogoff, and it measures frequency band is 100kHz-40MHz.The signal that two-way High Frequency Current Sensor is obtained accesses high-speed oscilloscope 12 by Hi-pass filter, Hi-pass filter 11 is binary channels, frequency range is lower limit 3.5MHz, can effectively suppress the low-frequency disturbance that displacement current that impulse voltage generator produces brings, signal wire adopts shielded cable, and its wave impedance is 50 ohm.The local discharge signal access oscillograph that the trial voltage signal that voltage divider obtains and High Frequency Current Sensor obtain gathers and analyzes, and oscillograph adopts Tyke 4104, has four-way, 1G bandwidth, 5GHz sampling rate.
In actual tests, according to the needs of test, can adjust flexibly each competition, for example, get: impulse voltage generator parameter can be chosen according to tested device rated voltage, and voltage divider no-load voltage ratio also can be chosen according to actual conditions.
Flow process of the present invention as shown in Figure 2, first applies 50% surge voltage to Transformer Winding, and now transformer shelf depreciation can not occur, as shown in flow process Figure 102, then by the High Frequency Current Sensor on bottom shielding of bushing ground lead and transformer body ground lead, carry out the measurement of ground unrest, background signal when acquisition transformer does not have shelf depreciation, then as shown in flow process Figure 103, Transformer Winding is applied to 100% surge voltage, gather the detected signal of High Frequency Current Sensor on bottom shielding of bushing ground lead and transformer body ground lead, if there is not shelf depreciation in transformer, now measurement result and measurement result that Transformer Winding is applied in 50% surge voltage are similar, if now there is shelf depreciation, there will be obvious discharge pulse, now also should judge that this discharge pulse is that transformer body produces by comparing the polarity of two-way High Frequency Current Sensor, or produced by external circuit.
The present invention judges that square ratio juris that whether discharge pulse produced by transformer body is as shown in accompanying drawing 3,4, transformer equivalent capacity 13 and sleeve pipe equivalent capacity 14, when discharge pulse is the generation of transformer external circuit, as shown in Figure 3, the direction of current impulse on two-way sensor is identical, and in the transformer equivalent capacity that it detects, pulse 15 is identical with pulse 16 polarity in sleeve pipe equivalent capacity.When discharge pulse is produced by transformer body, as shown in Figure 4, the opposite direction of current impulse on two-way sensor, in the transformer equivalent capacity that it detects, in pulse 15 and sleeve pipe equivalent capacity, pulse 16 polarity are contrary.The polarity that pulse detected according to two-way sensor can judge that discharge pulse is that transformer body produces, or external circuit produces, and can realize the analysis of interference and signal.
Above partial discharge of transformer pick-up unit and method thereof under a kind of surge voltage provided by the present invention are described in detail, applied specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment is just for helping to understand method of the present invention and core concept thereof; , for those skilled in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention meanwhile.
Claims (2)
1. partial discharge of transformer pick-up unit under a surge voltage, comprise impulse voltage generator (1), standard capacitor divider (2), transformer (5) and high-speed oscilloscope (12), it is characterized in that, between the output terminal of impulse voltage generator (1) and ground, be connected with standard capacitor divider (2), the output terminal of impulse voltage generator (1) is connected with the winding electric of transformer (5) by transformer high-voltage bushing (4), on the bottom shielding of bushing ground lead (6) of transformer high-voltage bushing (4), be socketed with the first High Frequency Current Sensor (8), the first High Frequency Current Sensor (8) is connected with the input end of Hi-pass filter (11), on the body ground lead (7) of transformer (5), be socketed with the second High Frequency Current Sensor (9), the second High Frequency Current Sensor (9) is connected with another input end of Hi-pass filter (11), the output terminal of Hi-pass filter (11) is connected with high-speed oscilloscope (12), the middle part output terminal of standard capacitor divider (2) is connected with high-speed oscilloscope (12) by signal wire (10).
2. partial discharge of transformer pick-up unit under a kind of surge voltage according to claim 1, is characterized in that, the intrinsic standoff ratio of standard capacitor divider (2) is 1000:1.
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103954890A (en) * | 2014-04-10 | 2014-07-30 | 国家电网公司 | DC partial discharge detection device and method for converter transformer |
| CN104217621A (en) * | 2014-09-29 | 2014-12-17 | 武汉大学 | Training simulation platform and method for high impulse voltage test |
| CN104459497A (en) * | 2014-12-18 | 2015-03-25 | 西安交通大学 | Device for measuring and analyzing partial discharge under surge voltage |
| CN104914365A (en) * | 2015-06-12 | 2015-09-16 | 国网天津市电力公司 | Detection device and method for improving partial discharge detection sensitivity |
| CN105699868A (en) * | 2016-03-08 | 2016-06-22 | 北京华天机电研究所有限公司 | Online monitoring system for power grid |
| CN106249118A (en) * | 2016-09-20 | 2016-12-21 | 国网天津市电力公司 | Based on GIS device superfrequency partial discharge detecting system under surge voltage |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
| CN107422231A (en) * | 2017-06-14 | 2017-12-01 | 西安交通大学 | A kind of transformer superfrequency local discharge detection device |
| CN107807311A (en) * | 2017-09-26 | 2018-03-16 | 杭州西湖电子研究所 | A kind of capacitive sleeve pipe high frequency partial discharge signal detection device |
| CN108267660A (en) * | 2018-03-21 | 2018-07-10 | 广东电网有限责任公司电力科学研究院 | A kind of Diagnosis Method of Transformer Faults and device |
| CN109298303A (en) * | 2018-09-05 | 2019-02-01 | 国网河北省电力有限公司电力科学研究院 | Transformer winding shelf depreciation propagation characteristic experimental rig and method |
| CN111458604A (en) * | 2019-12-27 | 2020-07-28 | 广东电网有限责任公司电力科学研究院 | Transformer self-sensing-based oscillation type lightning impulse test system and method |
| CN112731079A (en) * | 2020-12-24 | 2021-04-30 | 国网电力科学研究院武汉南瑞有限责任公司 | Partial discharge detection device for rapid development type fault of ultra-high voltage transformer |
| CN113203925A (en) * | 2021-04-29 | 2021-08-03 | 华南理工大学 | Partial discharge detection method |
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103954890A (en) * | 2014-04-10 | 2014-07-30 | 国家电网公司 | DC partial discharge detection device and method for converter transformer |
| CN104217621A (en) * | 2014-09-29 | 2014-12-17 | 武汉大学 | Training simulation platform and method for high impulse voltage test |
| CN104459497A (en) * | 2014-12-18 | 2015-03-25 | 西安交通大学 | Device for measuring and analyzing partial discharge under surge voltage |
| CN104914365A (en) * | 2015-06-12 | 2015-09-16 | 国网天津市电力公司 | Detection device and method for improving partial discharge detection sensitivity |
| CN104914365B (en) * | 2015-06-12 | 2017-08-29 | 国网天津市电力公司 | A kind of detection means and method for improving Partial Discharge Detection sensitivity |
| CN105699868A (en) * | 2016-03-08 | 2016-06-22 | 北京华天机电研究所有限公司 | Online monitoring system for power grid |
| CN106249118A (en) * | 2016-09-20 | 2016-12-21 | 国网天津市电力公司 | Based on GIS device superfrequency partial discharge detecting system under surge voltage |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
| CN107422231A (en) * | 2017-06-14 | 2017-12-01 | 西安交通大学 | A kind of transformer superfrequency local discharge detection device |
| CN107422231B (en) * | 2017-06-14 | 2020-01-31 | 西安交通大学 | transformer ultrahigh frequency partial discharge detection device |
| CN107807311A (en) * | 2017-09-26 | 2018-03-16 | 杭州西湖电子研究所 | A kind of capacitive sleeve pipe high frequency partial discharge signal detection device |
| CN107807311B (en) * | 2017-09-26 | 2023-08-01 | 杭州西湖电子研究所 | High-frequency partial discharge signal detection device for capacitive sleeve |
| CN108267660A (en) * | 2018-03-21 | 2018-07-10 | 广东电网有限责任公司电力科学研究院 | A kind of Diagnosis Method of Transformer Faults and device |
| CN108267660B (en) * | 2018-03-21 | 2020-02-14 | 广东电网有限责任公司电力科学研究院 | Transformer fault diagnosis method and device |
| CN109298303A (en) * | 2018-09-05 | 2019-02-01 | 国网河北省电力有限公司电力科学研究院 | Transformer winding shelf depreciation propagation characteristic experimental rig and method |
| CN111458604A (en) * | 2019-12-27 | 2020-07-28 | 广东电网有限责任公司电力科学研究院 | Transformer self-sensing-based oscillation type lightning impulse test system and method |
| CN112731079A (en) * | 2020-12-24 | 2021-04-30 | 国网电力科学研究院武汉南瑞有限责任公司 | Partial discharge detection device for rapid development type fault of ultra-high voltage transformer |
| CN113203925A (en) * | 2021-04-29 | 2021-08-03 | 华南理工大学 | Partial discharge detection method |
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Application publication date: 20140205 |