Power frequency partial discharge detection environment defect detection device and method

Abstract

The invention discloses a power frequency partial discharge environment defect detection device and method.The device comprises a rotatable inductance coil and a sensor for detecting the rotation amount of the inductance coil, and the two ends of the inductance coil are sequentially connected with a current detection circuit and a matched resistor to form a closed loop; the rotatable inductance coil is placed in a power frequency partial discharge detection environment, electromagnetic signals generated based on environmental defects in the power frequency partial discharge detection environment are converted into current signals, meanwhile, a sensor captures rotation angle signals of the inductance coil, and the approximate orientation of the environmental defects is determined through comparison processing. The device is specially used for detecting electromagnetic interference signals in a closed environment, engineering field troubleshooting and construction of an electromagnetic shielding experiment environment are greatly facilitated, and meanwhile the measuring circuit is simple in structure, high in adaptability, low in cost and high in safety coefficient.

Description

Technical Field

[0001] The present invention relates to the field of defect detection of electrical equipment, and particularly to a device and method for detecting defects in the power frequency partial discharge detection environment. Background Art

[0002] With the rapid development of the power system, higher requirements are imposed on the insulation performance of high-voltage electrical equipment. Power frequency partial discharge refers to the partial discharge phenomenon that occurs in electrical equipment under power frequency (50 Hz or 60 Hz) voltage. Partial discharge is a tiny discharge caused by internal insulation defects of the equipment, usually occurring at locations with concentrated electric fields or weak insulation. The power frequency partial discharge detection experiment is a test of the withstand voltage strength and partial discharge of electrical equipment and insulating materials to evaluate their insulation performance and safety performance. Generally, the experiment environment must be in an electromagnetic shielding state. Otherwise, external electromagnetic signal interference will not only affect the sensitivity of the detection instrument but also may lead to distortion of the test results. Therefore, it is often necessary to detect defects in the power frequency partial discharge detection environment before the experiment to determine whether the detection environment is qualified and ensure that the experiment is carried out in an absolute electromagnetic shielding state.

[0003] Regarding the defect detection of the power frequency partial discharge detection environment, electromagnetic interference is the primary factor affecting power frequency partial discharge detection. It will cause the partial discharge detector to receive false discharge signals, resulting in distortion of the test results and even misjudgment of the insulation state of the equipment. For example, when conducting a partial discharge test in a high-voltage electrical experiment center, due to the magnetic field in the internal closed environment caused by the door gap, the partial discharge test is interfered, which will greatly affect the partial discharge test. And the existing electromagnetic signal detection technology has not yet had a method to detect the location of the electromagnetic interference signal source in a closed environment. Therefore, it is necessary to develop a device and method for detecting defects in the power frequency partial discharge detection environment that can accurately and quickly detect the presence and approximate location of defects in the power frequency partial discharge detection environment, so as to quickly find and eliminate environmental defects, which is of great significance for improving the stability and safety of the power system. Summary of the Invention

[0004] The purpose of the present invention is to provide a device and method for detecting defects in the power frequency partial discharge detection environment based on electromagnetic induction. Through this device and method, the signal intensity and accurate location of the electromagnetic interference signal source generated due to environmental defects can be quickly detected. This method is particularly suitable for detecting electromagnetic interference signals in a closed environment, greatly facilitating the investigation at the engineering site and constructing an electromagnetic shielding experimental environment.

[0005] To solve the above technical problems, the technical solution of the present invention is: A power frequency partial discharge detection environment defect detection device, which includes a rotatable inductance coil and a sensor for detecting the rotation amount of the inductance coil. The two ends of the inductance coil are sequentially connected to a current detection circuit and a matching resistor to form a closed loop. The inductance coil is placed in a power frequency partial discharge detection environment, and the current detection circuit and the sensor are signal-connected to a data processing module.

[0006] Preferably, the inductance coil is a controllable rotating inductance coil driven by a motor.

[0007] Preferably, the sensor is an angle sensor or a gyroscope that rotates with the inductance coil.

[0008] Preferably, the inductance coil is fixed on the first surface of the DSP development board through an insulating fixed shaft. The current detection circuit and the data processing module are arranged on the DSP development board. The motor is fixedly connected to the second surface of the DSP development board, and the output shaft of the motor is perpendicular to the DSP development board.

[0009] Preferably, the inductance coil is a columnar spiral coil, and the axis of the inductance coil is parallel to the DSP development board.

[0010] A power frequency partial discharge detection environment defect detection method. Place a rotatable inductance coil in a power frequency partial discharge detection environment. It also includes a sensor for detecting the rotation amount of the inductance coil. The two ends of the inductance coil are sequentially connected to a current detection circuit and a matching resistor to form a closed loop. The current detection circuit and the sensor are signal-connected to a data processing module. During the rotation of the inductance coil, the electromagnetic signal in the power frequency partial discharge detection environment is converted into a current signal. At the same time, the sensor captures the rotation angle signal of the inductance coil. The current signal and the rotation angle signal are jointly transmitted to the data processing module and then compared and processed to obtain the rotation angle signal with the strongest electromagnetic signal, thereby determining the approximate orientation of the environmental defect.

[0011] Preferably, the inductance coil is a controllable rotating inductance coil driven by a motor, and the inductance coil is controlled by the motor to perform a 360° full-range scan of the electromagnetic signal in the power frequency partial discharge detection environment.

[0012] Preferably, the motor also drives a pointer to perform a 360° full-range rotation in the power frequency partial discharge detection environment. The data processing module is signal-connected to the motor, transmits the rotation angle signal with the strongest electromagnetic signal obtained to the motor, and the motor drives the pointer to point to the direction with the strongest electromagnetic signal.

[0013] Preferably, the inductance coil is fixed on the first surface of the DSP development board through an insulating fixed shaft, and the inductance coil is a columnar spiral coil, and the axis of the inductance coil is parallel to the DSP development board; the pointer is fixedly installed on the insulating fixed shaft, and the pointer is also parallel to the DSP development board. The DSP development board is provided with the current detection circuit and the data processing module, and the motor is fixedly connected to the second surface of the DSP development board and the output shaft of the motor is perpendicular to the DSP development board.

[0014] The present invention uses an automatically rotating inductance coil to detect electromagnetic signals generated by environmental defects based on power frequency partial discharge detection, and combines a data processing module and motor control. By collecting induction current and rotation angle signals and synchronizing the two in real time, the maximum value and angle of the current signal within a week are obtained through comparison. The motor is controlled by a motor control algorithm to rotate the azimuth indicator to the accurate position where the environmental defect is located. In this way, the signal intensity and accurate azimuth of the electromagnetic interference signal source can be intuitively displayed to the user. It is specially applied to detect electromagnetic interference signals in a closed environment, greatly facilitating the investigation at the engineering site and constructing an experimental environment for electromagnetic shielding. At the same time, its measurement circuit structure is simple, with high adaptability, low cost, and high safety factor. Brief Description of the Drawings

[0015] Figure 1 is a schematic structural diagram of the device of the present invention; Figure 2 is a perspective view of the device of the present invention. Detailed Embodiments

[0016] The present invention will be further described in detail below with reference to the drawings and specific embodiments. Embodiment 1

[0017] As Figure 1-2 shown, this embodiment will illustrate the present invention through a detailed description of a device for detecting environmental defects in power frequency partial discharge detection. The core components of the device include a rotatable inductance coil 1 and a sensor 5 for detecting the rotation amount of the inductance coil 1. The two ends of the inductance coil are sequentially connected to a current detection circuit 7 and a matching resistor to form a closed loop. The inductance coil 1 is placed in a power frequency partial discharge detection environment, and the current detection circuit 7 and the sensor 5 are signal-connected to a data processing module 8.

[0018] The main feature of the present invention is to detect the intensity and orientation of electromagnetic signals generated by environmental defects through the inductance coil 1 rotated by the motor 2. Specifically, the inductance coil 1 can be a controllable rotating inductance coil driven by the motor 2, and the output shaft of the motor 2 is fixedly connected to the inductance coil 1 directly or indirectly, so that the rotation of the motor 2 drives the inductance coil 1 to rotate, thereby realizing 360° omnidirectional scanning of electromagnetic signals by the device. During the scanning process, when there are defects in the detection environment, the electromagnetic signal interference source outside the detection environment will generate electromagnetic interference signals inside the detection environment through the defects. The electromagnetic signals will form changing magnetic fluxes inside the moving inductance coil 1, and then generate induced electromotive forces. The two ends of the inductance coil 1 are externally connected to the current detection circuit 7 to convert the detected weak electromagnetic signals into current signals 10, and the signal-to-noise ratio is improved through the current amplification circuit to ensure accurate signal capture. During installation, the inductance coil 1 can be selected as a cylindrical spiral coil, such as a cylindrical spiral coil or a prismatic spiral coil, and it is preferably made of copper wire. To improve the detection accuracy of the inductance coil 1, a central conductor can be further added inside the inductance coil 1, and the central conductor can be selected as an iron core. In this embodiment, the inductance coil 1 is fixedly connected to the motor 2 through a DSP development board. Specifically, the inductance coil 1 is fixed on the first surface of the DSP development board 4 through an insulating fixed shaft 12. When fixing, in order to make the detected electromagnetic signal orientation accurate, the axis of the inductance coil 1 can be designed to be parallel to the DSP development board 4. The current detection circuit 7 and the data processing module 8 are also provided on the DSP development board 4, and the inductance coil 1 is directly or indirectly signal-connected to these modules. The motor 2 for driving the inductance coil 1 is fixedly connected to the second surface of the DSP development board 4 and the output shaft 11 of the motor 2 is perpendicular to the DSP development board 4. In this way, when the motor 2 drives the DSP development board 4 to rotate, the inductance coil 1 can rotate within the plane where the DSP development board 4 is located and capture electromagnetic signals. As the inductance coil 1 rotates, the magnitude of the induced electromotive force changes continuously with the change of the rotation angle. Therefore, the orientation where the environmental defect is located can be judged by the magnitude of the induced electromotive force. When there are multiple electromagnetic interference signal sources in the environment, the change in the magnitude of the induced electromotive force can also effectively provide a reference and display the intensity of the electromagnetic interference signals.

[0019] To identify the location of environmental defects that generate electromagnetic signals, a sensor 5 for detecting the rotation amount of the inductance coil 1 is also provided on the inductance coil 1. Specifically, the sensor 5 can be installed on the inductance coil 1 or on the DSP development board 4. At the same time, a pointer 6 for indicating the direction of environmental defects can be fixedly installed on the upper surface of the DSP development board 4. In this embodiment, the pointer 6 can be fixed on the inductance coil 1 together with the sensor 5, or directly fixed on the first surface of the DSP development board 4. The sensor 5 can be an angle sensor 5 or a gyroscope that rotates with the inductance coil 1. The operating principles of the angle sensor 5 and the gyroscope are well-known and will not be elaborated here. In this embodiment, the angle sensor 5 is adopted. The angle sensor 5 is arranged on the axis of the output shaft of the motor 2. The angle sensor 5 can be HWT901B. After the starting point is determined by the angle sensor 5, the rotation angle signal 9 of the inductance coil 1 can be output in real time. The rotation angle signal 9 detected in real time and the current signal 10 obtained by the current detection circuit 7 are sent to the data processing module 8 together. After the data processing module 8 processes the current signal 10 and the rotation angle signal 9 through a real-time synchronization and comparison program, the rotation angle signal 9 corresponding to the captured strongest electromagnetic signal is obtained, and the motor 2 is instructed to make a feedback. Specifically, the device further includes a motor control module 3. The motor control module 3 is connected to the data processing module 8 and the motor 2 by signals at the same time. After the data processing module 8 sends the corresponding rotation angle signal 9 to the motor control module 3, the motor control module 3 translates the rotation angle signal 9 through a motor 2 rotation angle control algorithm and sends it to the motor 2 to drive the motor 2 to rotate, thereby driving the DSP development board 4 to rotate and making the pointer 6 point to the direction of the strongest electromagnetic signal, so as to determine the approximate location of the environmental defect. In addition, if the pointer 6 is designed to be perpendicular to the axis direction of the inductance coil 1, the location of the environmental defect can be directly determined by judging the magnitude of the current signal. Specifically, since when the induced electromotive force in the inductance coil 1 is the largest, the axial direction of the electromagnetic coil should be perpendicular to the direction of the defect at this time. Therefore, if the pointer 6 is also perpendicular to the axial direction of the inductance coil 1, the location of the electromagnetic interference signal source generated by the environmental defect can be directly obtained intuitively from the direction indicated by the pointer 6. Embodiment 2

[0020] A method for detecting environmental defects in power frequency partial discharge detection. An inductive coil 1 that can rotate can be placed in the power frequency partial discharge detection environment. It also includes a sensor 5 for detecting the rotation amount of the inductive coil 1. The two ends of the inductive coil 1 are sequentially connected to a current detection circuit 7 and a matching resistor to form a closed loop. The current detection circuit 7 and the sensor 5 are signal-connected to a data processing module 8. During the rotation of the inductive coil 1, the electromagnetic signal in the power frequency partial discharge detection environment is converted into a current signal 10. At the same time, the sensor 5 captures the rotation angle signal 9 of the inductive coil 1. The current signal 10 and the rotation angle signal 9 are jointly transmitted to the data processing module 8 and then compared and processed to obtain the rotation angle signal 9 with the strongest electromagnetic signal, thereby determining the approximate orientation of the environmental defect. Specifically, the inductive coil 1 is a controllable rotating inductive coil 1 driven by a motor 2. The inductive coil 1 is controlled by the motor 2 to perform a 360° omnidirectional scan of the electromagnetic signal in the power frequency partial discharge detection environment. During installation, the inductive coil 1 is fixed on the first surface of the DSP development board 4 through an insulating fixed shaft, and the inductive coil 1 is a columnar spiral coil, which can be a cylindrical spiral coil or a prismatic spiral coil. Further, a central conductor can be added inside the inductive coil 1 to improve the detection accuracy of the inductive coil 1, and the central conductor can be an iron core. To ensure the accuracy of detecting the orientation of the electromagnetic signal, it is designed that the axis of the inductive coil 1 is parallel to the DSP development board 4. When the inductive coil 1 rotates with the DSP development board 4, the inductive coil 1 can rotate within the plane where the DSP development board 4 is located and capture the electromagnetic signal caused by the environmental defect as much as possible. The inductive coil 1 and the DSP development board 4 are driven by a controllable motor 2. The motor 2 can be fixedly connected to the second surface of the DSP development board 4 and the output shaft of the motor 2 is perpendicular to the DSP development board 4. A motor control module 3 is installed on the DSP development board 4. The motor control module 3 can be arranged on the second surface of the DSP development board 4 and is signal-connected to the motor 2. A current detection circuit 7 and a data processing module 8 are also arranged on the DSP development board 4. The inductive coil 1 is signal-connected to the current detection circuit 7, and the detected induced current generated based on the environmental defect is transmitted to the data processing module 8 through the current detection circuit 7.

[0021] The inductive coil 1 is also equipped with a sensor 5 for detecting the rotation amount of the inductive coil 1. Specifically, the sensor 5 can be installed on the inductive coil 1 or on the DSP development board 4. The sensor 5 can be an angle sensor 5 that rotates with the inductive coil 1 or a gyroscope. When the sensor 5 is selected as the angle sensor 5, the angle sensor 5 is arranged on the axis of the output shaft of the motor 2. After determining the starting rotation point through the angle sensor 5, the rotation angle signal 9 of the inductive coil 1 can be output in real time. The rotation angle signal 9 detected in real time and the current signal 10 obtained by the current detection circuit 7 are jointly sent to the data processing module 8. After the data processing module 8 processes the current signal 10 and the rotation angle signal 9 through a real-time synchronization and comparison program, the rotation angle signal 9 corresponding to the captured strongest electromagnetic signal is obtained.

[0022] Further, the motor 2 also drives a pointer 6 to achieve a 360° full-circle rotation in the power frequency partial discharge detection environment. Since the data processing module 8 is signal-connected to the motor 2, after obtaining the rotation angle signal 9 with the strongest electromagnetic signal, it can transmit this signal to the motor 2, and the motor 2 drives the pointer 6 to point to the direction with the strongest electromagnetic signal. The pointer 6 can also be installed parallel to the DSP development board 4, and the pointer 6 remains perpendicular to the axis direction of the inductance coil 1.

[0023] When starting the detection, the motor control module 3 can first control the motor 2 to rotate at a constant speed for one week, driving the DSP development board 4 and the electromagnetic coil installed on its first surface to achieve a 360° full-circle rotation. The induced electromotive force on the inductance coil 1 will continuously change with the change of the rotation angle and is output to the current detection circuit 7. After filtering and amplification in the current detection circuit 7, the current signal 10 is output. The rotation angle signal 9 output by the angle sensor 5 and the current signal 10 after filtering and amplification in the current detection circuit 7 are transmitted to the data processing module 8 of the DSP development board 4 in real time. After passing through the synchronization processing program, the electromagnetic signal intensity data of each angular orientation can be obtained. After rotating one week, by comparing the magnitudes of the current signals 10, the rotation angle signal 9 corresponding to the maximum value of the current signal 10 within one week is obtained, and this rotation angle signal 9 is transmitted to the motor control module 3. Through the rotation angle control algorithm of the motor 2, the motor 2 is controlled to rotate to this angle, so that the user can quickly obtain the azimuth of the electromagnetic signal source generated by environmental defects through the pointer 6, greatly simplifying the work process of eliminating electromagnetic interference on site.

[0024] The above is only a preferred embodiment of the present invention, and does not impose any limitation on the technical scope of the present invention. Therefore, any changes or modifications made according to the claims and the description of the present invention shall fall within the scope covered by the patent of the present invention.

Claims

1. A power frequency partial discharge detection environment defect detection device, characterized in that: It includes a rotatable inductance coil and a sensor for detecting the rotation amount of the inductance coil. The two ends of the inductance coil are sequentially connected to a current detection circuit and a matching resistor to form a closed loop. The inductance coil is placed in a power frequency partial discharge detection environment, and the current detection circuit and the sensor are signal-connected to a data processing module.

2. The defect detection device for the power frequency partial discharge detection environment according to claim 1, characterized in that: The inductance coil is a controllable rotating inductance coil driven by a motor.

3. The environmental defect detection device for power frequency partial discharge detection according to claim 1, characterized in that: The sensor is an angle sensor or a gyroscope that rotates with the inductance coil.

4. A power frequency partial discharge detection environment defect detection device according to claim 2, characterized in that: The inductance coil is fixed on the first surface of the DSP development board through an insulating fixed shaft. The current detection circuit and the data processing module are arranged on the DSP development board. The motor is fixedly connected to the second surface of the DSP development board, and the output shaft of the motor is perpendicular to the DSP development board.

5. The environmental defect detection device for power frequency partial discharge detection according to claim 4, characterized in that: The inductance coil is a cylindrical spiral coil, and the axis of the inductance coil is parallel to the DSP development board.

6. A method for detecting environmental defects in power frequency partial discharge detection, characterized in that: A rotatable inductance coil is placed in a power frequency partial discharge detection environment, and it also includes a sensor for detecting the rotation amount of the inductance coil. The two ends of the inductance coil are sequentially connected to a current detection circuit and a matching resistor to form a closed loop. The current detection circuit and the sensor are signal-connected to a data processing module. During the rotation of the inductance coil, the electromagnetic signal in the power frequency partial discharge detection environment is converted into a current signal. At the same time, the sensor captures the rotation angle signal of the inductance coil. The current signal and the rotation angle signal are jointly transmitted to the data processing module and then compared and processed to obtain the rotation angle signal with the strongest electromagnetic signal, thereby determining the approximate orientation of the environmental defect.

7. A method for detecting environmental defects in power frequency partial discharge detection according to claim 6, characterized in that: The inductance coil is a controllable rotating inductance coil driven by a motor, and the inductance coil is controlled by the motor to perform a 360° omnidirectional scan of the electromagnetic signal in the power frequency partial discharge detection environment.

8. A method for detecting environmental defects in power frequency partial discharge detection, according to claim 7, characterized in that: The motor also drives a pointer to perform a 360° omnidirectional rotation in the power frequency partial discharge detection environment. The data processing module is signal-connected to the motor, transmits the rotation angle signal with the strongest electromagnetic signal obtained to the motor, and the motor drives the pointer to point to the direction with the strongest electromagnetic signal.

9. A method for detecting environmental defects in power frequency partial discharge detection, according to claim 8, characterized in that: The inductance coil is fixed on the first surface of the DSP development board through an insulating fixed shaft, and the inductance coil is a cylindrical spiral coil. The axis of the inductance coil is parallel to the DSP development board; the pointer is fixedly installed on the insulating fixed shaft, and the pointer is also parallel to the DSP development board. The current detection circuit and the data processing module are arranged on the DSP development board. The motor is fixedly connected to the second surface of the DSP development board, and the output shaft of the motor is perpendicular to the DSP development board.

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