CN103884967B - One is applicable to the inner partial discharge positioning method of UHV winding and device - Google Patents

Abstract

The invention discloses a method and device suitable for localizing partial discharge inside a UHV converter transformer winding. Polarizer integrated module, PIN photodetector and processing module, 16-channel partial discharge synchronous detection system, UHV converter transformer winding internal partial discharge positioning system; 16 optical fiber current sensors are built in the single-phase three-column parallel structure propagation circuit unit, to obtain the proportional relationship of partial discharge signals, and analyze the correlation characteristics of partial discharge signals with external valve side bushings, grid side bushings and core grounding, to realize the identification of interference signals and multi-column parallelism in the field partial discharge test of converter transformers. The positioning of the power supply on the network side and the valve side. It can effectively judge the insulation status of equipment, and provide a basis for experts to comprehensively evaluate the rheological performance of UHV converters.

Description

A method and device suitable for locating partial discharge inside a UHV converter transformer winding

technical field

The invention belongs to the technical field of power transmission and transformation equipment, and particularly relates to a ±1100kV large-capacity ultra-high voltage converter transformer winding internal partial discharge positioning method and device, which are suitable for long-term induction withstand voltage and external application of ultra-high voltage converter transformers in the factory or on site. DC withstand voltage with partial discharge test anti-interference and winding internal discharge source positioning.

Background technique

With the smooth development and implementation of the 1000kV UHV AC transmission project, the development and application of higher voltage level DC transmission technology has become a hot spot in the application of new power technologies and the main content of power grid planning. Utilizing the research results of ±800kV DC and drawing on the development experience of 1000kV AC UHV, the DC transmission system can increase the DC voltage level to ±1100kV to increase the transmission capacity on a large scale, and the selection of ±1100kV UHV DC can reduce the number of DC projects and reduce the number of lines Loss, save capital investment.

At present, the Zhundong-Sichuan UHV DC transmission project is planned to be completed and put into operation around 2015, with a transmission voltage level of ±1100kV and a transmission capacity of 10,000MW. The power transmission line of the DC project starts from the Xinjiang converter station, passes through the four provinces of Xinjiang, Gansu, Shaanxi, and Sichuan, and ends at the Sichuan converter station. The length of the line is about 2600km. The UHV converter transformer is one of the most important equipment in the UHV converter station. Its function is to convert the 500kV (or 750kV, 1000kV) grid-side AC voltage through the transformer into the valve-side AC voltage, which is rectified to ±1100kV by the converter valve. DC transmission. During operation, the valve side winding of the converter transformer is simultaneously subjected to the superimposed effects of various voltage forms such as DC, AC, impact, and harmonics. The requirements for insulation tolerance are higher. Under the condition of DC bias, the insulation inside the equipment The accumulation, migration and dissipation of space charges make the operating environment of the converter transformer even worse; at the moment of commutation or when the system transmits energy in reverse, it must also bear the polarity reversal voltage, which is likely to cause the local electric field concentration of the outlet device, threatening Device security.

Ultrasonic testing technology is a testing method that has gradually emerged in recent years. When a partial discharge occurs in a transformer, it will be accompanied by the release of sound wave energy. The sound wave propagates outward in different media (oil paper, separators, windings, oil, etc.) and reaches the acoustic emission sensor fixed on the wall of the transformer oil tank. Localization of partial discharge sources, however, the propagation path between the discharge source and the sensor is complex, the equivalent propagation velocity is difficult to determine, and the acoustic emission signal will be attenuated when propagating in different media, etc., which poses certain difficulties to the localization of partial discharge sources. The discharge cannot be located. During on-site partial discharge, the test product is in a complex electromagnetic interference environment, causing the weak partial discharge signal to be submerged in various strong interferences, making it difficult to obtain real useful information and the real insulation status of the equipment. Its reliability and safety cannot be guaranteed.

In view of this, it is necessary to provide a partial discharge localization method and device suitable for UHV converter transformer windings, to realize long-term induction withstand voltage of converter transformers or externally applied DC withstand voltage with partial discharge test interference identification and winding internal discharge positioning function to solve the above problems.

Contents of the invention

The purpose of the present invention is to provide a UHV converter transformer partial discharge anti-interference and winding internal discharge positioning method and device for the insufficiency of on-site partial discharge anti-interference ability and discharge positioning technology of UHV converter transformers. The optical fiber current sensor at the outlet end of different windings obtains the partial discharge signal proportional relationship, and analyzes the correlation characteristics with the partial discharge signal of the external valve side bushing, grid side bushing and core grounding, and realizes the interference signal in the field partial discharge test of the converter transformer. The identification of the multi-column parallel network side and the location of the discharge source on the valve side can effectively judge the insulation status of the equipment and provide a basis for experts to comprehensively evaluate the rheological performance of UHV converters.

In order to achieve the above purpose, the present invention provides a partial discharge positioning device suitable for UHV converter transformer windings, which is characterized in that it includes: DFB laser, optical fiber polarizer integrated module, single-phase three-column Parallel structure propagation circuit, optical fiber analyzer integrated module, PIN photodetector and processing module, 16-channel partial discharge synchronous detection system, UHV converter transformer winding internal partial discharge positioning system; among them, the single-phase three-column parallel structure propagation circuit Among them, there are 16 built-in all-optical current sensing units in the iron core grounding, valve side bushing, valve side winding, grid side bushing, grid side winding and voltage regulating winding outlet, and are numbered 1~16 respectively. The specific positions of the units are as follows: 1 is the external iron core grounding optical fiber current sensing unit; 2, 3 and 4 are the built-in optical fiber current sensing units for the three-column iron core grounding outlet; 5 and 6 are the external valve side bushing end screen grounding optical fiber current sensing units 7, 8 and 9 are built-in optical fiber current sensing units at the upper end of the winding on the three-column valve side; 10 is an optical fiber current sensing unit connected to the end screen of the bushing on the external network side; 11, 12 and 13 are three-column network side The upper end of the winding has a built-in optical fiber current sensing unit; 14, 15 and 16 are the built-in optical fiber current sensing unit for the upper end of the three-column voltage regulating winding; the DFB laser is used to radiate the beam; It becomes polarized light and enters into 1 to 16 sensing units respectively. After the polarization state is modulated by the magnetic field generated by the partial discharge pulse current, it forms a clip with the same direction as the polarization direction of the polarizer and an inclined ^45o through the integrated module of the optical fiber analyzer. The two beams of optical signals at the corners are detected by the PIN photodetector and the processing module, and the electrical signals converted from the same direction and the opposite direction of the corresponding channel are processed to obtain 1~16 pulse current signals to be measured, which are transmitted to the 16-channel partial discharge synchronous detection system, after preliminary analysis and transmission of diagnostic results to the internal partial discharge positioning system of UHV converter transformer windings.

The present invention provides a method for locating partial discharges inside the windings of UHV converter transformers, which adopts the above-mentioned locating device for partial discharges inside the windings of UHV converter transformers, and is characterized in that an all-optical current sensor is used for each The partial discharge high-frequency pulse current signal propagated by the winding is monitored, that is, the beam is radiated by the DFB laser, and after passing through the optical fiber polarizer integrated module, it becomes polarized light, which enters 1 to 16 sensing fibers respectively, and its polarization state is passed through the partial discharge After the modulation of the magnetic field generated by the pulse current, the integrated module of the optical fiber analyzer forms two beams of optical signals in the same direction as the polarization direction of the polarizer and at an angle of 45 ^° , which are detected by the PIN photodetector and the processing module, and the corresponding channels are processed The electrical signals converted by the same direction and different directions of light beams are obtained from 1 to 16 channels of pulse current signals to be tested, and transmitted to the 16-channel partial discharge synchronous detection system through a coaxial shielded cable. After preliminary analysis, the diagnostic results are transmitted to the UHV converter Partial discharge positioning system inside the transformer winding; among them, the amplitude of the pulse signal in the 16-channel partial discharge synchronous detection system is recorded as A ₁ -A ₁₆ , the core grounding monitoring point: A ₁ ≈ A ₂ +A ₃ +A ₄ , the valve side sleeve Tube monitoring point: A ₅ +A ₆ ≈A ₇ +A ₈ +A ₉ , grid-side bushing monitoring point: A ₁₀ ≈A ₁₁ +A ₁₂ +A ₁₃ ; preliminary parallel connection of single-phase three-column UHV converter The method for determining the location of the maximum magnitude partial discharge source of a structure is:

1) There is an obvious pulse signal at the core grounding monitoring point A ₁ , and the discharge iron core column is judged by the pulse amplitude of A ₂ , A ₃ and A ₄ :

If A ₂ ≈ A ₁ , the discharge source is located in the first core leg;

If A ₃ ≈ A ₁ , the discharge source is located in the second core leg;

If A ₄ ≈ A ₁ , the discharge source is located in the third core leg;

If the sum of A ₂ , A ₃ and A ₄ is close to the background, it is judged as an external interference signal;

₂ ) There are obvious pulse signals at valve side bushing monitoring points A5 and _A6 , and the discharge core column is judged by the pulse amplitudes of _A7 , _A8 and _A9 :

If A ₇ ≈A ₅ +A ₆ , the discharge source is located in the first core leg;

If A ₈ ≈A ₅ +A ₆ , the discharge source is located in the second core leg;

If A ₉ ≈A ₅ +A ₆ , the discharge source is located in the third core leg;

If the sum of A ₇ , A ₈ and A ₉ is close to the background, it is judged as an external interference signal;

3) There is an obvious pulse signal at the monitoring point A ₁₀ of the bushing on the grid side, and the discharge core column is judged by the pulse amplitude of A ₁₁ , A ₁₂ and A ₁₃ :

If A ₁₁ ≈A ₁₀ , the discharge source is located in the first core leg;

If A ₁₂ ≈ A ₁₀ , the discharge source is located in the second core leg;

If A ₁₃ ≈ A ₁₀ , the discharge source is located in the third core leg;

If the sum of A ₁₁ , A ₁₂ and A ₁₃ is close to the background, it is determined to be an external interference signal.

The beneficial effects of the present invention are: the present invention has a single-phase three-column parallel connection of each valve side winding, grid side winding and voltage regulating winding in the ±1100kV UHV converter transformer with a built-in full-optical current sensing unit at the upper end of the winding, which can effectively and accurately Identify discharge interference and discharge area; the present invention obtains the partial discharge transmission ratio characteristic relationship based on the equivalent capacitance distribution, and combines the partial discharge calibration method to establish the characteristic value of the partial discharge transmission efficiency calibration suitable for the field test product; in the present invention, the valve side The structural sequence of the winding, the grid side winding and the voltage regulating winding can be adjusted according to the structure of the test product. The partial discharge of the long-term induction withstand voltage and the partial discharge of the DC externally applied withstand voltage can be monitored by selecting different channels of all-fiber current sensing units.

Description of drawings

Fig. 1 is the ultra-high voltage converter transformer single-phase three-column parallel structure pulse current propagation circuit diagram of the present invention, in the figure: 101. single-phase three-column parallel structure propagation circuit; 17. iron core grounding, 18. oil tank wall grounding, 19. valve Side winding, 20. Grid side winding, 21. Regulating winding;

1 is the external iron core grounding fiber optic current sensing unit;

2, 3 and 4 are three-column iron core grounding outlets with built-in optical fiber current sensing units;

5 and 6 are externally connected to the valve side bushing end screen grounding optical fiber current sensing unit;

7, 8 and 9 are built-in optical fiber current sensing units for the upper end of the three-column valve side winding;

10 is an optical fiber current sensing unit connected to the grounding of the end screen of the bushing on the external network side;

11, 12 and 13 are built-in optical fiber current sensing units for the upper end of the three-column grid side winding;

14, 15 and 16 are built-in optical fiber current sensing units for the upper end of the three-column voltage regulating winding;

C _F is the geometrical capacitance of the valve side winding to the iron core, and the corresponding equivalent capacitance of each column winding is calculated;

C _FW is the geometric capacitance between the valve side winding and the network side winding, and the equivalent capacitance of each column winding is calculated;

C _WT is the geometric capacitance between the grid side winding and the voltage regulating winding, and the equivalent capacitance corresponding to each column winding is calculated;

C _T is the geometric capacitance of the voltage regulating winding to the tank wall, and the corresponding equivalent capacitance of each column winding is calculated;

C _BF is the capacitance of the bushing on the valve side; C _BW is the capacitance of the high voltage bushing on the grid side.

Fig. 2 is a structural diagram of the method and device for locating partial discharge inside the UHV converter transformer winding of the present invention. In the figure: 101. Single-phase three-column parallel structure propagation circuit, 102. DFB laser, 103. Optical fiber polarizer integrated module, 104. Integrated module of optical fiber analyzer, 105． PIN photodetector and processing module, 106. 16-channel partial discharge synchronous detection system, 107. Partial discharge localization system inside UHV converter transformer winding.

Figure 3 is a schematic diagram of the capacitance distribution of the UHV converter transformer. In the figure, r ₀ -r ₇ are the insulation radii of each part, and H is the reactance height of the winding.

Figure 4 shows the voltage distribution of the winding to the core.

Figure 5 shows the voltage distribution between the windings.

detailed description

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples. Those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms are also within the scope of the claims listed in this application.

As shown in Figure 1, in order to meet the ±1100kV UHV DC large-capacity transmission project, major domestic transformer design units designed the main structure of the UHV converter transformer as a single-phase three-column parallel structure, where C _F is the valve side winding to the core Geometric capacitance, calculate the equivalent capacitance corresponding to each column winding, C _F1 corresponds to the capacitance of the first column winding, C _F2 corresponds to the capacitance of the second column winding, C _F3 corresponds to the capacitance of the third column winding, the following is similar; C _FW C WT is the geometric capacitance between the valve side winding and the grid side winding, and the corresponding equivalent capacitance of each column winding is calculated; C _WT is the geometric capacitance between the grid side winding and the voltage regulating winding, and the corresponding equivalent capacitance of each column winding is calculated; C _T is the geometric capacitance of the voltage regulating winding to the tank wall, and the corresponding equivalent capacitance of each column winding is calculated; C _BF is the capacitance of the bushing on the valve side; C _BW is the capacitance of the high voltage bushing on the network side.

In the present invention, in the ±1100kV UHV converter transformer, the single-phase three-column parallel connection of each valve-side winding, network-side winding and voltage regulating winding has a built-in full-optical current sensing unit (shown as 1-16 in Figure 1) , the partial discharge measurement can effectively identify the location of the partial discharge source area inside the winding.

As shown in FIG. 2 , it is a structural principle diagram of the method and device for locating partial discharge inside the UHV converter transformer winding provided by the present invention. The partial discharge positioning device inside the UHV converter transformer winding of the present invention includes: DFB laser 102, optical fiber polarizer integrated module 103, single-phase three-column parallel structure propagation circuit 101, optical fiber analyzer integrated module 104, PIN photodetector and a processing module 105, a 16-channel partial discharge synchronous detection system 106, and a partial discharge positioning system 107 inside the UHV converter transformer winding.

The present invention uses an all-fiber current sensor suitable for pulse current measurement and has good insulation properties to monitor the partial discharge high-frequency pulse current signal propagated by each winding, that is, the DFB laser 102 radiates a beam, and the optical fiber polarizer integrated module 103 Afterwards, it becomes polarized light and enters into 1, 2..., 16 sensing optical fibers respectively. After the polarization state is modulated by the magnetic field generated by the partial discharge pulse current, it is formed by the optical fiber analyzer integrated module 104 in the same direction as the polarization direction of the polarizer. The two beams of optical signals with an angle of 45 ^° to and inclined are detected by the PIN photodetector and the processing module 105, and the electrical signals converted from the same and different beams of the corresponding channels are processed to obtain 1~16 channels of pulse current signals to be tested. It is transmitted to the 16-channel partial discharge synchronous detection system 106 through the coaxial shielded cable, the partial discharge characteristic information is initially analyzed, and selected and transmitted to the internal partial discharge positioning system 107 of the UHV converter transformer winding according to the diagnosis result.

Among them, the pulse signal amplitude in the 16-channel partial discharge synchronous detection system 106 is recorded as A ₁ -A ₁₆ , the iron core grounding monitoring point: A ₁ ≈ A ₂ +A ₃ +A ₄ , the valve side bushing monitoring point: A ₅ + A ₆ ≈A ₇ +A ₈ +A ₉ , monitoring point of casing at the wire side: A ₁₀ ≈A ₁₁ +A ₁₂ +A ₁₃ .

Preliminary determination of the location of the maximum amplitude partial discharge source of the single-phase three-column parallel structure of the UHV converter transformer:

1) There is an obvious pulse signal at the core grounding monitoring point A ₁ , and the discharge iron core column is judged by the pulse amplitude of A ₂ , A ₃ and A ₄ :

If A ₂ ≈ A ₁ , the discharge source is located in the first core leg;

If A ₃ ≈ A ₁ , the discharge source is located in the second core leg;

If A ₄ ≈ A ₁ , the discharge source is located in the third core leg;

If the sum of A ₂ , A ₃ and A ₄ is close to the background, it is determined to be an external interference signal.

₂ ) There are obvious pulse signals at valve side bushing monitoring points A5 and _A6 , and the discharge core column is judged by the pulse amplitudes of _A7 , _A8 and _A9 :

If A ₇ ≈A ₅ +A ₆ , the discharge source is located in the first core leg;

If A ₈ ≈A ₅ +A ₆ , the discharge source is located in the second core leg;

If A ₉ ≈A ₅ +A ₆ , the discharge source is located in the third core leg;

If the sum of A ₇ , A ₈ and A ₉ is close to the background, it is determined as an external interference signal.

3) There is an obvious pulse signal at the monitoring point A ₁₀ of the bushing on the grid side, and the discharge core column is judged by the pulse amplitude of A ₁₁ , A ₁₂ and A ₁₃ :

If A ₁₁ ≈A ₁₀ , the discharge source is located in the first core leg;

If A ₁₂ ≈ A ₁₀ , the discharge source is located in the second core leg;

If A ₁₃ ≈ A ₁₀ , the discharge source is located in the third core leg;

If the sum of A ₁₁ , A ₁₂ and A ₁₃ is close to the background, it is determined to be an external interference signal.

1. Calculation of equivalent capacitance.

In the partial discharge test of UHV converter transformer with long-term induction voltage, the current of the test object is capacitive. Since the induced voltages between the windings are different, the voltage of the same winding (to the ground) is distributed according to the number of turns, the capacitance between the windings and the winding to the ground presents a distribution parameter, and the distribution of the capacitance current is more complicated. A concentrated parameter can be used to represent the windings or the windings. The equivalent capacitance to the ground, its value is related to the geometric capacitance between the windings and the winding to the ground, and the voltage between the windings and the winding to the ground when the transformer is excited.

1) Transformer geometry capacitance calculation.

As shown in Figure 3, the geometric capacitance calculation formula of each capacitor is as follows:

(1)

In the formula, 1.15—edge effect increases the capacitance coefficient; Φ—conversion coefficient (the capacitance between the fuel tank and the voltage regulating winding is calculated as a coaxial cylinder, which needs to be multiplied by Φ), Φ=0.75; εr, εr′—dielectric coefficient ; r ₀ -r ₇ is the insulation radius of each part; H is the reactance height of the winding.

2) The capacitive energy storage formula between the transformer winding and the core (oil tank).

As shown in Figure 4, the total capacitance of the valve side winding to the core is (i.e. CF or C T _{) ,} and along Evenly distributed; the voltage at both ends of the winding to the core is and , and the winding voltage along the Evenly distributed.

exist Take a point on the axis, ; take the width , the corresponding capacitance is , , let the capacitor The charging power is ,but:

(2)

The total charging power in capacitor C is:

(3)

3) Capacitive energy storage formula between transformer windings.

In the formula (3) and Respectively replaced by the voltage between the ends of the two plates of the capacitor and , the formula (3) becomes the capacitance between the windings (that is, the energy storage formula of C _FW or C _WT ). As shown in Figure 4, the voltages at both ends of the right side winding are respectively and , the voltages across the left winding are and , at point The voltage is:

(4)

Assume , , the above formula becomes .

The total charging power in capacitor C is:

(5)

4) Calculation of equivalent capacitance.

With the highest winding voltage as benchmark pair and Take the per unit value and convert formula (5) into charging power and relational formula to obtain exist Under the equivalent capacitance. Formula (5) can be written as:

Assume is the equivalent capacitance, then:

Assume ; , the above formula can be simplified into the following form:

(6)

Through this method, the equivalent capacitance of each column valve side to the iron core can be calculated , , , the equivalent capacitance between the valve side winding and grid side winding of each column , , , the equivalent capacitance between each column grid side winding and voltage regulating winding , , , the equivalent capacitance of each column voltage regulating winding to the tank wall , , . Obtain the capacitance of the bushing at the high-voltage side of the grid side and the bushing at the valve side according to the technical data list of the field test product , , .

2. Partial discharge transmission efficiency eigenvalue

1) Eigenvalue of partial discharge transmission efficiency of valve side winding.

Short-circuit the outlet bushings of the valve side windings, inject 500pC, 1000pC and 2000pC calibration charges into the valve side windings through the JFD-301 calibration pulse generator, and record the peak values of the apparent discharges received by the 16 channels as - , - , - , and the signal amplitude is recorded as zero if it is the background noise. In calibration, no voltage is applied, and the equivalent capacitance under each calibration charge is replaced by geometric capacitance.

(7)

If the calibration charge is 500pC, ,and , then the - Set as the standard calibration characteristic parameter; if it does not meet, and ,and , then the - Set as the standard calibration characteristic parameter, if it does not meet, set - Set as the standard calibration characteristic parameter.

If the partial discharge test of the converter transformer is performed on the valve side bushing and The actual detected apparent discharge amount is , and the discharge source is located in the winding area of the valve side, the actual total discharge capacity is not greater than:

(8)

2) Eigenvalues of partial discharge transmission efficiency of grid-side windings.

Through the JFD-301 calibration pulse generator, 500pC, 1000pC and 2000pC calibration charges are injected into the outlet bushing of the high-voltage end of the grid side winding, and the 16-channel receiving apparent discharge is respectively recorded as - , - , - , and the signal amplitude is recorded as zero if it is the background noise. In calibration, no voltage is applied, and the equivalent capacitance under each calibration charge is replaced by geometric capacitance.

(9)

If the calibration charge is 500pC, ,and , then the - Set as the standard calibration characteristic parameter; if it does not meet, and ,and , then the - Set as the standard calibration characteristic parameter, if it does not meet, set - Set as the standard calibration characteristic parameter.

If the partial discharge test of the converter transformer is performed on the grid side bushing The actual detected apparent discharge capacity is , and the discharge source is located in the grid side winding area, the actual total discharge capacity is not greater than:

(10)

3) Eigenvalue of partial discharge transmission efficiency of voltage regulating winding.

Short-circuit the outlet bushing of the voltage regulating winding, inject 500pC, 1000pC and 2000pC calibration charges into the voltage regulating winding through the JFD-301 calibration pulse generator, and record the apparent discharge amount of the 16 channels as - , - , - , and the signal amplitude is recorded as zero if it is the background noise. In calibration, no voltage is applied, and the equivalent capacitance under each calibration charge is replaced by geometric capacitance.

(11)

If the calibration charge is 500pC, , then the - Set as the standard calibration characteristic parameter; if it does not meet, , then the - Set as the standard calibration characteristic parameter, if it does not meet, set - Set as the standard calibration characteristic parameter.

3. Partial discharge anti-interference and regional positioning in the winding

1) Interference identification.

In this detection system, channels 1, 5, 6 and 10 are the pulse current signal monitoring points for core grounding, valve side bushing end screen grounding, and network side bushing end screen grounding respectively, which are easy to receive interference signals from external electromagnetic circuits. The remaining channels are built-in sensing units, which can effectively shield interference and can be identified by the following methods:

(1) When channel 1 receives a pulse signal, and channels 2, 3 and 4 do not receive the signal amplitude and the sum is greater than the signal of channel 1, it is a ground network interference signal;

(2) When channels 5 and 6 receive pulse signals, but channels 7, 8 and 9 do not receive effective identification signals, the reorganized signals are interference signals;

(3) When channel 10 receives a pulse signal, but channels 11, 12 and 13 do not receive an effective identification signal, then this group of signals is an interference signal.

2) The location of the discharge source inside the winding.

The transmission capacity of the ±1100kV UHV converter transformer is extremely large. According to the current design, the body of the single-phase converter transformer is three-column parallel connection, with yokes on both sides. The winding volume is huge. According to the existing ultrasonic positioning technology, the internal discharge of the winding cannot be effectively located. The main purpose of the present invention is to provide a positioning technology for the internal discharge area of the winding for the UHV converter transformer, and the specific identification method is as follows:

(1) Preliminarily judge the winding position of the discharge source through the pulse amplitude sequence of channels 1, 5, 6 and 10 of the external sensing unit. If the amplitude of channels 5 and 6 is much greater than that of channels 1 and 10, the main discharge source It is defined as the valve side winding, and so on, to judge whether there is a main discharge source in the grid side winding and the iron core respectively;

(2) If it is preliminarily judged that the main discharge source is in the winding on the valve side, check the signals of the same group, if the signal amplitude of channel 7 is much larger than that of channels 8 and 9, and at the same time there are signals with calibration ratios in channels 11 and 2, the discharge source can be determined Located in the area near the valve side winding of the first winding column, the valve side and grid side windings of the three columns can be deduced by analogy to determine the location of the discharge source;

(3) If the signal amplitudes of channels 1, 2, 3, and 4 are much larger than those of other channels, it can be determined that the discharge source and the iron core are more related;

(4) If the signal amplitudes of channels 14, 15, and 16 are relatively large, and the signal amplitudes of other channels are relatively small, it can be preliminarily judged that it is the peripheral discharge of the device or related to the voltage regulating winding, and ultrasonic positioning technology can be used for detection.

In the present invention, the structural sequence of the valve side winding, the network side winding and the voltage regulating winding can be adjusted according to the structure of the test product. The partial discharge of the long-term induced voltage withstand zone and the partial discharge of the DC externally applied withstand voltage zone can be selected by selecting different channels for all-fiber current transmission. Sensing unit for monitoring.

Claims (1)

1. one kind is applicable to the inner shelf depreciation positioner of UHV winding, it is characterized in that, comprise successively by the data flow order of connection: Distributed Feedback Laser, optical fiber polarizer integration module, single-phase three post parallel-connection structure propagation circuits, optical fiber analyzer integration module, PIN photodetector and processing module, the 16 path partiallies inner shelf depreciation navigation system of synchronous detection system, UHV winding of discharging; Wherein in single-phase three post parallel-connection structure propagation circuits, respectively 16 of iron core grounding, valve side sleeve pipe, valve side winding, net side sleeve pipe, net side winding and the built-in full optical-fiber current sensing units of pressure regulation winding outlet, and being numbered respectively 1 ~ 16, its particular location of each sensing unit is as follows: 1 is external iron core grounding fiber-optic current sensor unit; 2,3 and 4 is three-limb core ground connection outlet built-in fiber current sensing unit; 5 and 6 is external valve side bottom shielding of bushing ground connection fiber-optic current sensor unit; 7,8 and 9 is three column valve side winding upper end outlet built-in fiber current sensing units; 10 is external net side bottom shielding of bushing ground connection fiber-optic current sensor unit; 11,12 and 13 is three post net side winding upper end outlet built-in fiber current sensing units; 14,15 and 16 is three post pressure regulation winding upper end outlet built-in fiber current sensing units; Distributed Feedback Laser is used for giving off light beam; Optical fiber polarizer integration module for light beam is become to polarised light, enters respectively 1 Zhi16 road sensing unit, after the modulation that its polarization state produces magnetic field through pulse current of PD, through optical fiber analyzer integration module form with polarizer polarization direction in the same way with tilt 45^oThe two-beam signal of angle, detect by PIN photodetector and processing module, and process respective channel in the same way with the signal of telecommunication of incorgruous light beam conversion, obtain 1 ~ 16 tunnel pulsed current signal to be measured, transfer to the 16 path partiallies synchronous detection system of discharging through coaxial shielded cable, transfer to the inner shelf depreciation navigation system of UHV winding through initial analysis and by diagnostic result.