A partial discharge detection positioning system and method based on ultrasonic detection

Abstract

The application provides a partial discharge detection positioning system based on ultrasonic detection, which comprises a broadband laser source, a first coupler, a second coupler, a third coupler, a first optical fiber, a second optical fiber, a fourth coupler, a third optical fiber, a first optical fiber sensor, a fourth optical fiber, a fifth coupler, a fifth optical fiber, a sixth optical fiber, a seventh optical fiber, a sixth coupler, an eighth optical fiber, a second optical fiber sensor, a ninth optical fiber, a seventh coupler, a tenth optical fiber, an optical / electricity conversion unit, a signal conditioning unit, a control processing unit, a key input unit, a storage unit, a display unit, an alarm unit and a communication unit; the detection positioning system acquires a partial discharge signal, and calculates a partial discharge position according to a signal time difference collected by the optical fiber sensor. The partial discharge detection positioning system and method based on ultrasonic detection can accurately detect a partial discharge fault and a fault position of a power equipment.

Description

Technical Field

[0001] This invention belongs to the field of power detection technology, and specifically relates to a partial discharge detection and positioning system and detection method based on ultrasonic detection. Background Technology

[0002] With continuous economic development, the power industry is also constantly evolving, and people's demand for electricity is increasing. Currently, there are numerous types of electrical equipment used, and early-stage insulation faults in electrical equipment often manifest as partial discharge. Real-time online detection of partial discharge, early identification, and rapid and accurate location of partial discharge are urgent issues that need to be addressed to ensure the safe operation of power equipment and even the power grid. Therefore, partial discharge detection is an important basis for the safety evaluation of power equipment. Partial discharge phenomena are accompanied by electrical, optical, acoustic, and thermal phenomena, and ultrasonic signals are one of the important indicators for insulation detection.

[0003] This invention proposes a partial discharge detection and positioning system based on ultrasonic detection. It determines whether the device under test has experienced partial discharge based on the influence of the partial discharge signal on the light intensity of the optical signal output by the broadband laser source. The detection is accurate and convenient. At the same time, the distance between the partial discharge point and the optical fiber sensor is calculated based on the time difference of the information collected by the two optical fiber sensors, so as to realize the detection and positioning of partial discharge faults. Summary of the Invention

[0004] This invention provides a partial discharge detection and location system and method based on ultrasonic detection, which can accurately detect partial discharge faults and fault locations in power equipment, ensuring the safe and reliable operation of power equipment.

[0005] This invention specifically relates to a partial discharge detection and positioning system based on ultrasonic detection. The partial discharge detection and positioning system includes a broadband laser source, a first coupler, a second coupler, a third coupler, a first optical fiber, a second optical fiber, a fourth coupler, a third optical fiber, a first optical fiber sensor, a fourth optical fiber, a fifth coupler, a fifth optical fiber, a sixth optical fiber, a seventh optical fiber, a sixth coupler, an eighth optical fiber, a second optical fiber sensor, a ninth optical fiber, a seventh coupler, a tenth optical fiber, a photoelectric conversion unit, a signal conditioning unit, a control processing unit, a key input unit, a storage unit, a display unit, an alarm unit, and a communication unit. The first coupler is connected to the broadband laser source and the second coupler's optical fiber. The second coupler is sequentially connected to the first optical fiber, the fourth coupler, the third optical fiber, the first optical fiber sensor, the fourth optical fiber, and the fifth coupler. The second optical fiber is connected to the second coupler and the fourth coupler. The fifth... The optical fibers are connected to the fourth and fifth couplers respectively. The third coupler is sequentially connected to the sixth optical fiber, the sixth coupler, the eighth optical fiber, the second optical fiber sensor, the ninth optical fiber, and the seventh coupler. The seventh optical fiber is connected to the third and sixth couplers respectively. The tenth optical fiber is connected to the sixth and seventh couplers respectively. The optical-to-electrical conversion unit is connected to the second coupler, the third coupler, and the signal conditioning unit respectively. The control processing unit is connected to the key input unit, the storage unit, the display unit, the alarm unit, and the communication unit respectively. The partial discharge detection and positioning system acquires partial discharge signals based on light interference, compares and determines whether the device under test has experienced partial discharge, and issues an alarm in a timely manner. At the same time, it calculates the location of the partial discharge based on the time difference between the signals acquired by the first and second optical fiber sensors.

[0006] The broadband laser source uses a power-adjustable broadband light source with an output center wavelength of 1550nm and an operating wavelength range of 1510nm to 1590nm.

[0007] The first coupler is a 3×3 fiber optic coupler, the second, third, fourth, and sixth couplers are 2×2 fiber optic couplers, and the fifth and seventh couplers are 1×2 fiber optic couplers. The splitting ratio at each port is 1:1, and the insertion loss at each port is less than 5.6dB.

[0008] The first optical fiber is longer than the second optical fiber; the sixth optical fiber is longer than the seventh optical fiber.

[0009] The optical-to-electric conversion unit uses a PIN photodiode to convert optical signals into electrical signals for output.

[0010] The signal conditioning unit includes an amplification module and an A / D conversion module. The amplification module uses an operational amplifier to amplify the input signal in reverse and outputs a voltage signal that meets the input requirements of the A / D conversion unit. The A / D conversion module converts the analog signal into a digital signal for output.

[0011] The key input unit, in conjunction with the display unit and the storage unit, performs parameter setting and information query. The parameters include the output wavelength of the broadband laser source, the discharge signal reference value, the distance between the first fiber optic sensor and the second fiber optic sensor, and the propagation speed of light in the fiber optic.

[0012] The alarm unit uses an audible and visual alarm, which promptly issues an audible and visual alarm signal when the partial discharge detection system detects a partial discharge fault.

[0013] The communication unit uses wireless communication technology to upload the information detected by the partial discharge detection system to the monitoring center.

[0014] The present invention also provides a detection and positioning method for a partial discharge detection and positioning system based on ultrasonic detection, the detection and positioning method comprising the following steps:

[0015] Step (1): The broadband laser source outputs an optical signal, which is transmitted to the first coupler;

[0016] Step (2): The first coupler transmits the optical signal to the second coupler and the third coupler via optical fiber;

[0017] Step (3): The optical signal output by the second coupler is transmitted to the fourth coupler through the first optical fiber and the second optical fiber respectively; the optical signal output by the third coupler is transmitted to the sixth coupler through the sixth optical fiber and the seventh optical fiber respectively;

[0018] Step (4): The optical signal output by the fourth coupler is transmitted to the first optical fiber sensor through the third optical fiber; the optical signal output by the sixth coupler is transmitted to the second optical fiber sensor through the eighth optical fiber;

[0019] Step (5): The optical signal output by the first optical fiber sensor is transmitted to the fifth coupler through the fourth optical fiber; the optical signal output by the second optical fiber sensor is transmitted to the seventh coupler through the ninth optical fiber;

[0020] Step (6): The optical signal output by the fifth coupler is transmitted to the fourth coupler via the fifth optical fiber; the optical signal output by the seventh coupler is transmitted to the sixth coupler via the tenth optical fiber;

[0021] Step (7): The output signal of the fourth coupler is transmitted to the second coupler through the first optical fiber and the second optical fiber respectively; the output signal of the sixth coupler is transmitted to the third coupler through the sixth optical fiber and the seventh optical fiber respectively;

[0022] Step (8): The output signal of the second coupler is transmitted to the optical / electric conversion unit via optical fiber; the output signal of the third coupler is transmitted to the optical / electric conversion unit via optical fiber.

[0023] Step (9): The optical signal is converted into a voltage signal and output through the optical / electric conversion unit;

[0024] Step (10): The amplification process is performed using the amplification module;

[0025] Step (11): Analog-to-digital conversion is performed through the A / D conversion module;

[0026] Step (12): The control processing unit compares the input signal with the discharge signal reference value. If the signal is greater than the discharge signal reference value, the control unit controls the alarm unit and the display unit to issue a partial discharge alarm. If the signal is not greater than the discharge signal reference value, the process returns to step (1).

[0027] Step (13): Calculate the time difference Δt between the two signals;

[0028] Step (14): Calculate the distance between the partial discharge location and the first fiber optic sensor. Distance from the second fiber optic sensor L is the distance between the first fiber optic sensor and the second fiber optic sensor, and v is the speed of light in the fiber optic cable.

[0029] Step (15): The communication unit uploads the detection results to the monitoring center.

[0030] Compared with existing technologies, the beneficial effects are: the partial discharge detection system determines whether the device under test has experienced partial discharge based on the influence of the partial discharge signal on the light intensity of the optical signal output by the broadband laser source, and can realize long-distance, distributed, fast real-time partial discharge detection. At the same time, it calculates the distance between the partial discharge point and the optical fiber sensor based on the time difference of the information collected by the two optical fiber sensors, thereby realizing the localization of the partial discharge fault point. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of a partial discharge detection and positioning system based on ultrasonic detection according to the present invention. Detailed Implementation

[0032] The following detailed description, with reference to the accompanying drawings, illustrates a specific embodiment of the partial discharge detection and positioning system based on ultrasonic detection according to the present invention.

[0033] like Figure 1 As shown, the partial discharge detection and positioning system of the present invention includes a broadband laser source, a first coupler, a second coupler, a third coupler, a first optical fiber, a second optical fiber, a fourth coupler, a third optical fiber, a first optical fiber sensor, a fourth optical fiber, a fifth coupler, a fifth optical fiber, a sixth optical fiber, a seventh optical fiber, a sixth coupler, an eighth optical fiber, a second optical fiber sensor, a ninth optical fiber, a seventh coupler, a tenth optical fiber, a photoelectric conversion unit, a signal conditioning unit, a control processing unit, a key input unit, a storage unit, a display unit, an alarm unit, and a communication unit. The first coupler is connected to the broadband laser source and the second coupler optical fiber respectively. The second coupler is sequentially connected to the first optical fiber, the fourth coupler, the third optical fiber, the first optical fiber sensor, the fourth optical fiber, and the fifth coupler. The second optical fiber is connected to the second coupler and the fourth coupler respectively. The fifth optical fiber is connected to the fourth coupler respectively. The system is connected to the device and the fifth coupler. The third coupler is sequentially connected to the sixth optical fiber, the sixth coupler, the eighth optical fiber, the second optical fiber sensor, the ninth optical fiber, and the seventh coupler. The seventh optical fiber is connected to the third coupler and the sixth coupler. The tenth optical fiber is connected to the sixth coupler and the seventh coupler. The optical-to-electric conversion unit is connected to the second coupler, the third coupler, and the signal conditioning unit. The control processing unit is connected to the key input unit, the storage unit, the display unit, the alarm unit, and the communication unit. The partial discharge detection and positioning system acquires partial discharge signals based on light interference, compares them to determine whether the device under test has experienced partial discharge, and issues an alarm in a timely manner. At the same time, it calculates the location of the partial discharge based on the time difference between the signals acquired by the first optical fiber sensor and the second optical fiber sensor.

[0034] The broadband laser source uses a power-adjustable broadband light source with an output center wavelength of 1550nm and an operating wavelength range of 1510nm to 1590nm.

[0035] The first coupler is a 3×3 fiber optic coupler, the second, third, fourth, and sixth couplers are 2×2 fiber optic couplers, and the fifth and seventh couplers are 1×2 fiber optic couplers. The splitting ratio at each port is 1:1, and the insertion loss at each port is less than 5.6dB.

[0036] The optical signal emitted by the broadband laser source is transmitted through the first coupler to the second coupler and the third coupler, and is divided into two sets of detection loops:

[0037] The first set of detection circuits are as follows: First path: Second coupler - First optical fiber - Fourth coupler - Third optical fiber - First optical fiber sensor - Fourth optical fiber - Fifth coupler - Fifth optical fiber - Fourth coupler - Second optical fiber - Second coupler; Second path: Second optical fiber - Fourth coupler - Third optical fiber - First optical fiber sensor - Fourth optical fiber - Fifth coupler - Fifth optical fiber - Fourth coupler - First optical fiber - Second coupler; The two optical path circuits interfere with each other at the Second coupler, forming an interference loop. Due to the influence of partial discharge, the light intensities of the two optical path circuits reaching the Second coupler are not equal.

[0038] The second set of detection circuits are as follows: Third path: Third coupler - Sixth fiber - Sixth coupler - Eighth fiber - Second fiber sensor - Ninth fiber - Seventh coupler - Tenth fiber - Sixth coupler - Seventh fiber - Third coupler; Fourth path: Seventh fiber - Sixth coupler - Eighth fiber - Second fiber sensor - Ninth fiber - Seventh coupler - Tenth fiber - Sixth coupler - Sixth fiber - Third coupler; The two optical path circuits interfere with each other at the Third coupler, forming an interference loop. Due to the influence of partial discharge, the light intensity of the two optical path circuits reaching the Third coupler is not equal.

[0039] The first optical fiber is longer than the second optical fiber; the sixth optical fiber is longer than the seventh optical fiber.

[0040] The optical-to-electric conversion unit uses a PIN photodiode to convert optical signals into electrical signals for output.

[0041] The signal conditioning unit includes an amplification module and an A / D conversion module. The amplification module uses an operational amplifier to amplify the input signal in reverse and outputs a voltage signal that meets the input requirements of the A / D conversion unit. The A / D conversion module converts the analog signal into a digital signal for output.

[0042] The key input unit, in conjunction with the display unit and the storage unit, performs parameter setting and information query. The parameters include the output wavelength of the broadband laser source, the discharge signal reference value, the distance between the first fiber optic sensor and the second fiber optic sensor, and the propagation speed of light in the fiber optic.

[0043] The alarm unit uses an audible and visual alarm, which promptly issues an audible and visual alarm signal when the partial discharge detection system detects a partial discharge fault.

[0044] The communication unit uses wireless communication technology to upload the information detected by the partial discharge detection system to the monitoring center.

[0045] The present invention also provides a detection and positioning method for a partial discharge detection and positioning system based on ultrasonic detection, the detection and positioning method comprising the following steps:

[0046] Step (1): The broadband laser source outputs an optical signal, which is transmitted to the first coupler;

[0047] Step (2): The first coupler transmits the optical signal to the second coupler and the third coupler via optical fiber;

[0048] Step (3): The optical signal output by the second coupler is transmitted to the fourth coupler through the first optical fiber and the second optical fiber respectively; the optical signal output by the third coupler is transmitted to the sixth coupler through the sixth optical fiber and the seventh optical fiber respectively;

[0049] Step (4): The optical signal output by the fourth coupler is transmitted to the first optical fiber sensor through the third optical fiber; the optical signal output by the sixth coupler is transmitted to the second optical fiber sensor through the eighth optical fiber;

[0050] Step (5): The optical signal output by the first optical fiber sensor is transmitted to the fifth coupler through the fourth optical fiber; the optical signal output by the second optical fiber sensor is transmitted to the seventh coupler through the ninth optical fiber;

[0051] Step (6): The optical signal output by the fifth coupler is transmitted to the fourth coupler via the fifth optical fiber; the optical signal output by the seventh coupler is transmitted to the sixth coupler via the tenth optical fiber;

[0052] Step (7): The output signal of the fourth coupler is transmitted to the second coupler through the first optical fiber and the second optical fiber respectively; the output signal of the sixth coupler is transmitted to the third coupler through the sixth optical fiber and the seventh optical fiber respectively;

[0053] Step (8): The output signal of the second coupler is transmitted to the optical / electric conversion unit via optical fiber; the output signal of the third coupler is transmitted to the optical / electric conversion unit via optical fiber.

[0054] Step (9): The optical signal is converted into a voltage signal and output through the optical / electric conversion unit;

[0055] Step (10): The amplification process is performed using the amplification module;

[0056] Step (11): Analog-to-digital conversion is performed through the A / D conversion module;

[0057] Step (12): The control processing unit compares the input signal with the discharge signal reference value. If the signal is greater than the discharge signal reference value, the control unit controls the alarm unit and the display unit to issue a partial discharge alarm. If the signal is not greater than the discharge signal reference value, the process returns to step (1).

[0058] Step (13): Calculate the time difference Δt between the two signals;

[0059] Step (14): Calculate the distance between the partial discharge location and the first fiber optic sensor. Distance from the second fiber optic sensor L is the distance between the first fiber optic sensor and the second fiber optic sensor, and v is the speed of light in the fiber optic cable.

[0060] Step (15): The communication unit uploads the detection results to the monitoring center.

[0061] Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention and not intended to limit it. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the specific embodiments of the present invention, but such modifications or alterations are all within the scope of protection of the pending claims.

Claims

1. A partial discharge detection and positioning system based on ultrasonic detection, characterized in that, The partial discharge detection and positioning system includes a broadband laser source, a first coupler, a second coupler, a third coupler, a first optical fiber, a second optical fiber, a fourth coupler, a third optical fiber, a first optical fiber sensor, a fourth optical fiber, a fifth coupler, a fifth optical fiber, a sixth optical fiber, a seventh optical fiber, a sixth coupler, an eighth optical fiber, a second optical fiber sensor, a ninth optical fiber, a seventh coupler, a tenth optical fiber, a photoelectric conversion unit, a signal conditioning unit, a control processing unit, a key input unit, a storage unit, a display unit, an alarm unit, and a communication unit. The first coupler is connected to the broadband laser source and the second coupler's optical fiber. The second coupler is sequentially connected to the first optical fiber, the fourth coupler, the third optical fiber, the first optical fiber sensor, the fourth optical fiber, and the fifth coupler. The second optical fiber is connected to the second coupler and the fourth coupler. The fifth optical fiber is connected to the fourth coupler, the... The fifth coupler is connected to the third coupler, which is sequentially connected to the sixth optical fiber, the sixth coupler, the eighth optical fiber, the second optical fiber sensor, the ninth optical fiber, and the seventh coupler. The seventh optical fiber is connected to the third coupler and the sixth coupler, and the tenth optical fiber is connected to the sixth coupler and the seventh coupler. The optical-to-electrical conversion unit is connected to the second coupler, the third coupler, and the signal conditioning unit. The control processing unit is connected to the key input unit, the storage unit, the display unit, the alarm unit, and the communication unit. The partial discharge detection and positioning system acquires partial discharge signals based on light interference, compares and determines whether the device under test has experienced partial discharge, and issues an alarm in a timely manner. Simultaneously, it calculates the location of the partial discharge based on the time difference between the signals acquired by the first optical fiber sensor and the second optical fiber sensor. The broadband laser source adopts a power-adjustable broadband light source with an output center wavelength of 1550nm and an operating wavelength range of 1510nm ~ 1590nm. The first coupler is a 3×3 fiber optic coupler, the second, third, fourth, and sixth couplers are 2×2 fiber optic couplers, and the fifth and seventh couplers are 1×2 fiber optic couplers. The splitting ratio at each port is 1:1, and the insertion loss at each port is less than 5.6dB. The first optical fiber is longer than the second optical fiber; the sixth optical fiber is longer than the seventh optical fiber.

2. The partial discharge detection and positioning system based on ultrasonic detection according to claim 1, characterized in that, The optical-to-electric conversion unit uses a PIN photodiode to convert optical signals into electrical signals for output.

3. The partial discharge detection and positioning system based on ultrasonic detection according to claim 2, characterized in that, The signal conditioning unit includes an amplification module and an A / D conversion module. The amplification module uses an operational amplifier to amplify the input signal in reverse and outputs a voltage signal that meets the input requirements of the A / D conversion unit. The A / D conversion module converts the analog signal into a digital signal for output.

4. The partial discharge detection and positioning system based on ultrasonic detection according to claim 3, characterized in that, The key input unit, in conjunction with the display unit and the storage unit, performs parameter setting and information query. The parameters include the output wavelength of the broadband laser source, the discharge signal reference value, the distance between the first fiber optic sensor and the second fiber optic sensor, and the propagation speed of light in the fiber optic.

5. A partial discharge detection and positioning system based on ultrasonic detection according to claim 4, characterized in that, The alarm unit uses an audible and visual alarm to promptly issue an audible and visual alarm signal when the partial discharge detection and positioning system detects a partial discharge fault; the communication unit uses wireless communication technology to upload the information detected by the partial discharge detection and positioning system to the monitoring center.

6. The detection and positioning method of the partial discharge detection and positioning system based on ultrasonic detection according to any one of claims 1-5, characterized in that, The detection and localization method includes the following steps: Step (1): The broadband laser source outputs an optical signal and transmits it to the first coupler; Step (2): The first coupler transmits the optical signal to the second coupler and the third coupler via optical fiber; Step (3): The optical signal output by the second coupler is transmitted to the fourth coupler through the first optical fiber and the second optical fiber respectively; the optical signal output by the third coupler is transmitted to the sixth coupler through the sixth optical fiber and the seventh optical fiber respectively; Step (4): The optical signal output by the fourth coupler is transmitted to the first optical fiber sensor through the third optical fiber; the optical signal output by the sixth coupler is transmitted to the second optical fiber sensor through the eighth optical fiber; Step (5): The optical signal output by the first optical fiber sensor is transmitted to the fifth coupler through the fourth optical fiber; the optical signal output by the second optical fiber sensor is transmitted to the seventh coupler through the ninth optical fiber; Step (6): The optical signal output by the fifth coupler is transmitted to the fourth coupler via the fifth optical fiber; the optical signal output by the seventh coupler is transmitted to the sixth coupler via the tenth optical fiber; Step (7): The output signal of the fourth coupler is transmitted to the second coupler through the first optical fiber and the second optical fiber respectively; the output signal of the sixth coupler is transmitted to the third coupler through the sixth optical fiber and the seventh optical fiber respectively; Step (8): The output signal of the second coupler is transmitted to the optical / electric conversion unit via optical fiber; the output signal of the third coupler is transmitted to the optical / electric conversion unit via optical fiber. Step (9): The optical signal is converted into a voltage signal and output through the optical / electric conversion unit; Step (10): Amplification is performed using the amplification module; Step (11): Analog-to-digital conversion is performed via the A / D conversion module; Step (12): The control processing unit compares the input signal with the discharge signal reference value. If the signal is greater than the discharge signal reference value, the control unit controls the alarm unit and the display unit to issue a partial discharge alarm. If the signal is not greater than the discharge signal reference value, the process returns to step (1). Step (13): Calculate the time difference between the two signals. ; Step (14): Calculate the distance between the partial discharge location and the first fiber optic sensor. Distance from the second fiber optic sensor , The distance between the first fiber optic sensor and the second fiber optic sensor. The speed at which light travels in an optical fiber; Step (15): The communication unit uploads the detection results to the monitoring center.

Images