Insulator voltage and resistance two-in-one tester

Abstract

The utility model discloses an insulator voltage and resistance two-in-one tester, which comprises an acquisition machine and a receiver, the acquisition machine and the receiver realize data transmission and reception through a wireless communication module, and the acquisition machine comprises a voltage and resistance switching circuit which is used for switching between a voltage measurement mode and a resistance measurement mode according to test requirements. Therefore, the measurement of voltage or resistance parameters is realized. The system also comprises an amplification circuit, an ADC, a first microcontroller and a data calibration circuit. According to the insulator voltage and resistance two-in-one tester, the testing process is simplified and the working efficiency is improved by integrating voltage and resistance measuring functions. The LoRa chip is adopted, so that remote transmission of data is realized, complex wiring requirements are avoided, and meanwhile, stability and reliability of data transmission are ensured. Accurate conversion and processing of measurement signals are ensured through a high-precision amplification circuit and an analog-to-digital converter.

Description

Technical Field

[0001] This utility model relates to the field of power testing equipment technology, and in particular to an insulator voltage and resistance combined tester. Background Technology

[0002] The insulation condition of insulators in high-voltage transmission lines is a critical factor directly affecting the safe and stable operation of the lines. If insulators become dirty, are damaged by lightning strikes, or suffer other insulation deterioration, they must be cleaned or replaced; otherwise, flashover tripping accidents may occur. Therefore, according to relevant standards, insulators in operation require regular and effective inspection.

[0003] According to DL / T626-2005 "Test Procedure for Deteriorated Disc Suspension Insulators", one effective method is to test the voltage distribution of the insulator string during operation, that is, to measure the distributed voltage across each insulator. Another method is to quantitatively measure the resistance value of each insulator. By measuring the distributed voltage or insulation resistance value of each insulator under energized (or de-energized) conditions, the quality of the insulator can be judged, so as to replace insulators that do not meet the requirements in a timely manner, ensuring the reliable and safe operation of the transmission line.

[0004] However, existing insulator testing equipment typically only measures voltage or resistance individually. For example, utility model patent application number 202221277216.9 discloses a wireless intelligent insulator resistance tester, which has both insulator resistance testing and wireless data transmission functions, but lacks voltage measurement capabilities. When both voltage and resistance need to be measured simultaneously, separate devices must be carried, increasing the workload of testing personnel and reducing testing efficiency. Furthermore, existing equipment has shortcomings in data transmission and calibration, such as limited transmission distance and the inability to effectively eliminate hardware errors, all of which affect the accuracy and reliability of the test results.

[0005] Therefore, this utility model provides a new solution to this problem. Utility Model Content

[0006] In view of the above situation and to overcome the defects of the prior art, the purpose of this utility model is to provide an insulator voltage and resistance combined tester.

[0007] The technical solution is: an insulator voltage and resistance combined tester, including a data acquisition unit and a receiver. The data acquisition unit and the receiver achieve data transmission and reception through a wireless communication module. The data acquisition unit includes:

[0008] The voltage-resistance switching circuit is used to switch between voltage measurement mode and resistance measurement mode according to test requirements, so as to realize the measurement of voltage or resistance parameters.

[0009] An amplifier circuit is used to amplify the measurement signal received from the voltage-resistance switching circuit.

[0010] An ADC is used to convert amplified analog signals into digital signals for subsequent digital processing and analysis.

[0011] The first microcontroller is used to control the working state of the voltage-resistance switching circuit, coordinate the working process of the amplifier circuit and the ADC, process and calculate the received digital signal, generate corresponding measurement data, and send the data to the receiver through the wireless communication module.

[0012] The data calibration circuit is used to connect to an external calibration device via a USB-MINI interface to calibrate the acquired voltage and resistance data.

[0013] Preferably, the voltage-resistance switching circuit includes:

[0014] The high-voltage detection unit is equipped with a first high-voltage probe, a second high-voltage probe, and a reed relay. The first high-voltage probe is connected to the first normally open contact of the reed relay through a first resistor and a second resistor, and the second normally open contact of the reed relay is grounded. The second high-voltage probe is connected to the voltage / resistance measurement output terminal through a third resistor.

[0015] The mode control unit sets up the power supply circuit for the reed relay coil and controls the conduction state of the reed relay according to the instructions of the first microcontroller:

[0016] When the reed relay coil is turned on, the tester operates in voltage measurement mode;

[0017] When the reed relay coil is de-energized, the tester operates in resistance measurement mode;

[0018] A clamping protection unit, connected to the voltage / resistance measurement output terminal, is used to clamp and protect the amplitude of the measurement signal.

[0019] A ground switching unit is used to select the ground resistance for the measurement signal output by the clamping protection unit to adapt to different measurement modes.

[0020] Preferably, the mode control unit includes a transistor Q1, the collector of which is connected to the first end of the reed relay coil, the second end of the reed relay coil is connected to a +5V power supply, the emitter of which is grounded, and the base of which is connected to the RELAY_EN control output terminal of the first microcontroller through a fourth resistor.

[0021] Preferably, the clamping protection unit includes a first diode and a second diode. The cathode of the first diode is connected to a +5V power supply, and the anode of the first diode and the cathode of the second diode are connected to the voltage / resistance measurement output terminal and the input terminal of the ground switching unit. The anode of the second diode is grounded.

[0022] Preferably, the ground switching unit includes an analog switch, a voltage measurement grounding component, and a resistance measurement grounding component. Pins 1A and 2A of the analog switch are connected to the voltage / resistance measurement output terminal, pin 1B of the analog switch is connected to the resistance measurement grounding component, pin 2B of the analog switch is connected to the voltage measurement grounding component, pin 1C of the analog switch is connected to the SWITCH_1 control output terminal of the first microcontroller, and pin 2C of the analog switch is connected to the SWITCH_2 control output terminal of the first microcontroller.

[0023] Preferably, the voltage measurement grounding assembly includes a fifth resistor and a first capacitor, one end of the fifth resistor and the first capacitor is connected to pin 2B of the analog switch, the other end of the fifth resistor and the first capacitor is grounded, and the resistance of the fifth resistor is 1KΩ.

[0024] Preferably, the resistance measurement grounding assembly includes a sixth resistor and a second capacitor. One end of the sixth resistor and the second capacitor is connected to pin 1B of the analog switch, and the other end of the sixth resistor and the second capacitor is grounded. The resistance of the sixth resistor is 15KΩ.

[0025] Preferably, the amplification circuit uses the AD8226 instrumentation amplifier.

[0026] Preferably, the first microcontroller is an HC32L130J8TA-LQ48 MCU.

[0027] Preferably, the wireless communication module uses a LoRa chip.

[0028] The beneficial effects of this utility model through the above technical solutions are as follows: The insulator voltage and resistance combined tester of this application simplifies the testing process and improves work efficiency by integrating voltage and resistance measurement functions. Its use of a LoRa chip enables remote data transmission, avoiding complex wiring requirements while ensuring the stability and reliability of data transmission. High-precision amplification circuits and analog-to-digital converters ensure accurate conversion and processing of measurement signals. Furthermore, the introduction of a microcontroller unit enables the device to automatically switch measurement modes and perform data calibration, further improving the accuracy and convenience of the test. Attached Figure Description

[0029] Figure 1 This is a system module structure diagram of the insulator voltage and resistance combined tester of this utility model.

[0030] Figure 2 This is a block diagram illustrating the control principle of the voltage-resistance switching circuit in this utility model.

[0031] Figure 3 This is the circuit diagram of the high-voltage detection unit of this utility model.

[0032] Figure 4 This is a circuit diagram of the mode control unit in this utility model.

[0033] Figure 5 This is a circuit diagram of the clamping protection unit in this utility model.

[0034] Figure 6 This is the wiring diagram of the external pins of the analog switch U2 in this utility model.

[0035] Figure 7 This is a circuit diagram of the voltage measurement grounding component and the resistance measurement grounding component in this utility model.

[0036] Figure 8 This is a schematic diagram of the connection circuit between the amplifier circuit and the ADC in this utility model.

[0037] Figure 9 This is the circuit schematic diagram of the first microcontroller in this utility model.

[0038] Figure 10 This is a schematic diagram of the data calibration circuit in this utility model.

[0039] Figure 11 This is a circuit diagram of the LoRa chip in this utility model. Detailed Implementation

[0040] The foregoing and other technical contents, features and effects of this utility model are described in conjunction with the appendix below. Figure 1 To be continued Figure 11The detailed description of the embodiments will make this clear. All structural details mentioned in the following embodiments are based on the accompanying drawings.

[0041] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings.

[0042] like Figure 1 As shown, the insulator voltage and resistance combined tester includes a data acquisition unit and a receiver. The data acquisition unit and the receiver realize data transmission and reception through a wireless communication module.

[0043] In the above, the data acquisition device specifically includes:

[0044] The voltage-resistance switching circuit is used to switch between voltage measurement mode and resistance measurement mode according to test requirements, so as to realize the measurement of voltage or resistance parameters.

[0045] An amplifier circuit is used to amplify the measurement signal received from a voltage-resistance switching circuit.

[0046] An ADC is used to convert amplified analog signals into digital signals for subsequent digital processing and analysis.

[0047] The first microcontroller is used to control the working state of the voltage-resistance switching circuit, coordinate the working process of the amplifier circuit and ADC, process and calculate the received digital signals, generate corresponding measurement data, and send the data to the receiver through the wireless communication module.

[0048] The data calibration circuit is used to connect to an external calibration device via a USB-MINI interface to calibrate the acquired voltage and resistance data.

[0049] In one specific embodiment, such as Figure 2 As shown, the voltage-resistance switching circuit includes:

[0050] The high-voltage detection unit is equipped with a first high-voltage probe, a second high-voltage probe, and a reed relay. The first high-voltage probe is connected to the first normally open contact of the reed relay through a first resistor R1 and a second resistor R2. The second normally open contact of the reed relay is grounded. The second high-voltage probe is connected to the voltage / resistance measurement output terminal R / V_COLLECT through a third resistor R3.

[0051] The mode control unit sets up the power supply circuit for the reed relay coil and controls the conduction state of the reed relay according to the instructions of the first microcontroller:

[0052] When the reed relay coil is turned on, the tester operates in voltage measurement mode;

[0053] When the reed relay coil is de-energized, the tester operates in resistance measurement mode;

[0054] The clamping protection unit is connected to the voltage / resistance measurement output terminal R / V_COLLECT and is used to clamp the amplitude of the measurement signal for protection output.

[0055] The ground switching unit is used to select the ground resistance for the measurement signal output by the clamping protection unit to adapt to different measurement modes.

[0056] In the specific implementation process, such as Figure 3 As shown, the reed relay in the high-voltage detection unit is model HVR05-2A06, which has a high withstand voltage and good insulation performance, ensuring reliable operation in high-voltage environments. Figure 4 As shown, the mode control unit includes a transistor Q1. The collector of transistor Q1 is connected to the first end of the reed relay coil, the second end of the reed relay coil is connected to a +5V power supply, the emitter of transistor Q1 is grounded, and the base of transistor Q1 is connected to the RELAY_EN control output terminal of the first microcontroller through a fourth resistor R4.

[0057] After the tester receives the measurement mode switching command, the first microcontroller controls the mode control unit by outputting high and low levels through the RELAY_EN port. The specific control process is as follows: When switching to voltage measurement mode, the RELAY_EN control output terminal of the first microcontroller outputs a high-level signal, energizing the base of transistor Q1 and thus energizing the reed relay coil, closing its normally open contacts 1 and 3. Conversely, if switching to resistance measurement mode, RELAY_EN outputs a low level, transistor Q1 is cut off, the reed relay coil is de-energized, and its normally open contacts 1 and 3 are open.

[0058] To prevent electromagnetic interference or high-voltage pulses generated during high-voltage detection from damaging the testing instrument, a clamping protection unit is installed to clamp the amplitude of the measurement signal output by the high-voltage detection unit within the range of 0 to +5V, thus preventing damage to electronic components in subsequent circuits due to excessive voltage. Specifically, for example... Figure 5 As shown, the clamping protection unit includes a first diode D1 and a second diode D2. The cathode of the first diode D1 is connected to a +5V power supply, and the anode of the first diode D1 is connected to the cathode of the second diode D2 to the voltage / resistance measurement output terminal R / V_COLLECT and the input terminal of the ground switching unit. The anode of the second diode D2 is grounded.

[0059] During the measurement process, the main function of the ground switching unit is to select the appropriate ground resistance according to different measurement modes, so as to adapt to the different needs of voltage measurement and resistance measurement. Specifically, for example... Figure 6As shown, the ground switching unit includes an analog switch U2, a voltage measurement grounding component, and a resistance measurement grounding component. Pins 1A and 2A of the analog switch are connected to the voltage / resistance measurement output terminal R / V_COLLECT. Pin 1B of the analog switch is connected to the resistance measurement grounding component. Pin 2B of the analog switch is connected to the voltage measurement grounding component. Pin 1C of the analog switch is connected to the SWITCH_1 control output terminal of the first microcontroller. Pin 2C of the analog switch is connected to the SWITCH_2 control output terminal of the first microcontroller.

[0060] In practical implementation, the aforementioned analog switch U2 is a four-channel analog switch of model SN74HC4066DR, and its specific working process is as follows:

[0061] When the tester is in voltage measurement mode, the first microcontroller outputs a high-level control signal to pin 2C of the SN74HC4066DR, which in turn connects pins 2A and 2B via the SWITCH_2 control output. This connects the voltage / resistance measurement output R / V_COLLECT to the voltage measurement grounding component.

[0062] Similarly, when the tester needs to switch to resistance measurement mode, the first microcontroller will output a high-level control signal from pin 1C of SN74HC4066DR, and through the SWITCH_1 control output, make pins 1A and 1B conduct, connecting the voltage / resistance measurement output R / V_COLLECT to the resistance measurement grounding component.

[0063] Through the precise control and switching process of the aforementioned ground switching unit, the circuit can be quickly and accurately turned on and off according to the switching requirements of the measurement mode, providing a suitable grounding path for voltage and resistance measurements, and ensuring the accurate measurement and reliable operation of the tester under different measurement conditions.

[0064] In specific implementation, such as Figure 7 As shown, the voltage measurement grounding assembly includes a fifth resistor R15 and a first capacitor C9. One end of the fifth resistor R15 and the first capacitor C9 is connected to pin 2B of the analog switch, and the other end of the fifth resistor R15 and the first capacitor C9 is grounded. The resistance of the fifth resistor R15 is 1KΩ. The resistance measurement grounding assembly includes a sixth resistor R16 and a second capacitor C8. One end of the sixth resistor R16 and the second capacitor C8 is connected to pin 1B of the analog switch, and the other end of the sixth resistor R16 and the second capacitor C8 is grounded. The resistance of the sixth resistor R16 is 15KΩ.

[0065] By setting the resistance value in the aforementioned grounding components, appropriate current and voltage distribution can be ensured in the measurement circuit when measuring insulators with different resistance values, resulting in more accurate measurement results. Furthermore, the capacitor acts as a filter, protecting the measurement circuit from high-frequency noise interference during measurement and improving the quality of the measurement signal.

[0066] In one specific embodiment, such as Figure 8 As shown, the amplifier circuit uses the AD8226 instrumentation amplifier to receive the measurement signal from the voltage-resistance switching circuit. The AD8226 has high input impedance, a characteristic that prevents it from causing a significant load effect on the preceding circuit when receiving signals; that is, it does not draw a large amount of current from the preceding circuit, thus ensuring that the signal transmission of the preceding circuit is unaffected and preserving the information of the input signal to the greatest extent. The AD8226 amplifies the weak measurement signal to a level suitable for ADC conversion, ensuring that the subsequent ADC can accurately convert the analog signal into a digital signal, avoiding quantization errors and resolution reduction caused by excessively low signal strength. The ADC uses the ADS8675IPWR analog-to-digital converter chip to receive the analog signal amplified by the AD8226. This chip, with its high resolution, can accurately quantize the analog signal into a digital signal, improving measurement accuracy.

[0067] In the specific implementation process, such as Figure 9 As shown, the first microcontroller is an HC32L130J8TA-LQ48 MCU, which has rich peripheral interfaces and high-performance processing capabilities, enabling it to efficiently coordinate the operation of various functional circuits. The MCU processes and calculates the digital signals output by the ADC to generate corresponding voltage or resistance measurement data.

[0068] To ensure data accuracy and reliability, the MCU will also connect to an external calibration device via a USB-MINI interface. In specific implementations, such as... Figure 10 As shown, the CH340N chip is used to implement USB function conversion. During calibration, the external calibration device sends a standard signal to the data acquisition unit via the USB-MINI interface. For voltage calibration, the standard voltage signal provided by the external calibration device is compared with the voltage signal measured by the data acquisition unit; for resistance calibration, the measurement result corresponding to the standard resistance signal provided by the external calibration device is compared with the resistance signal measured by the data acquisition unit. Based on the comparison result, the MCU can adjust the parameters of relevant circuits inside the data acquisition unit, such as adjusting the gain of the amplifier circuit, the reference voltage of the ADC, or other relevant circuit parameters, to calibrate the measurement system.

[0069] In the remote data transmission process between the acquisition unit and the receiver, the wireless communication module uses a LoRa chip, such as... Figure 11As shown, the LoRa chip, with its advantages of low power consumption and long-distance communication, ensures stable data transmission. During data transmission, after the first microcontroller sends the measurement data to the LoRa chip, the LoRa chip encodes and modulates the data. By using spread spectrum modulation technology, the data information is distributed across a wider frequency band to improve the signal's anti-interference capability. At the receiving end, the LoRa chip decodes and demodulates the data from the received RF signal, recovering the original digital data from the received RF signal and transmitting it to the receiver's MCU.

[0070] At the receiving end, the receiver of the insulator voltage and resistance combined tester of this application consists of a human-machine interface, a data storage module, a USB circuit, a Bluetooth circuit, a button circuit, and a second microprocessor. The second microprocessor verifies and processes the received data, including checking data integrity and performing data format conversion to ensure data accuracy and ease of use. The processed data is stored in the data storage module, which can store data according to time, insulator number, etc., for subsequent query and analysis. Then, the human-machine interface displays the stored data to the operator in an intuitive way. The operator can view different information, such as the voltage and resistance measurement values ​​of the insulator, measurement time, and measurement mode, and can also view historical data trends through touch or button operation. The USB circuit can export data to an external storage device, while the Bluetooth circuit can transmit data to Bluetooth devices such as mobile phones, allowing the operator to view and analyze data using a mobile APP or upload it to the cloud. In addition, the operator can input operation commands through buttons or the human-machine interface, which are processed by the second microprocessor and sent to the acquisition unit through the LoRa chip to control the measurement process.

[0071] In summary, the insulator voltage and resistance integrated tester of this application simplifies the testing process and improves work efficiency by integrating voltage and resistance measurement functions. Its LoRa chip enables remote data transmission, avoiding complex wiring requirements while ensuring the stability and reliability of data transmission. High-precision amplification circuits and analog-to-digital converters ensure accurate conversion and processing of measurement signals. Furthermore, the introduction of a microcontroller unit allows the device to automatically switch measurement modes and perform data calibration, further enhancing the accuracy and convenience of the test. Overall, the tester of this application simplifies the operation process and reduces operating costs while maintaining measurement accuracy, demonstrating high practical value and market competitiveness.

[0072] The above description is a further detailed explanation of the present utility model in conjunction with specific embodiments, and it should not be considered that the specific implementation of the present utility model is limited to this. For those skilled in the art to which the present utility model pertains and related fields, any extensions, operation methods, and data substitutions made based on the technical solution concept of the present utility model should fall within the protection scope of the present utility model.

Claims

1. An insulator voltage and resistance combined tester, comprising a data acquisition unit and a receiver, wherein the data acquisition unit and the receiver achieve data transmission and reception through a wireless communication module, characterized in that, The data acquisition device includes: The voltage-resistance switching circuit is used to switch between voltage measurement mode and resistance measurement mode according to test requirements, so as to realize the measurement of voltage or resistance parameters. An amplifier circuit is used to amplify the measurement signal received from the voltage-resistance switching circuit. An ADC is used to convert amplified analog signals into digital signals for subsequent digital processing and analysis. The first microcontroller is used to control the working state of the voltage-resistance switching circuit, coordinate the working process of the amplifier circuit and the ADC, process and calculate the received digital signal, generate corresponding measurement data, and send the data to the receiver through the wireless communication module. The data calibration circuit is used to connect to an external calibration device via a USB-MINI interface to calibrate the acquired voltage and resistance data.

2. The insulator voltage and resistance combined tester according to claim 1, characterized in that, The voltage-resistance switching circuit includes: The high-voltage detection unit is equipped with a first high-voltage probe, a second high-voltage probe, and a reed relay. The first high-voltage probe is connected to the first normally open contact of the reed relay through a first resistor and a second resistor, and the second normally open contact of the reed relay is grounded. The second high-voltage probe is connected to the voltage / resistance measurement output terminal through a third resistor. The mode control unit sets up the power supply circuit for the reed relay coil and controls the conduction state of the reed relay according to the instructions of the first microcontroller: When the reed relay coil is turned on, the tester operates in voltage measurement mode; When the reed relay coil is de-energized, the tester operates in resistance measurement mode; A clamping protection unit, connected to the voltage / resistance measurement output terminal, is used to clamp and protect the amplitude of the measurement signal. A ground switching unit is used to select the ground resistance for the measurement signal output by the clamping protection unit to adapt to different measurement modes.

3. The insulator voltage and resistance combined tester according to claim 2, characterized in that, The mode control unit includes a transistor Q1. The collector of the transistor Q1 is connected to the first end of the reed relay coil, the second end of the reed relay coil is connected to a +5V power supply, the emitter of the transistor Q1 is grounded, and the base of the transistor Q1 is connected to the RELAY_EN control output terminal of the first microcontroller through a fourth resistor.

4. The insulator voltage and resistance combined tester according to claim 3, characterized in that, The clamping protection unit includes a first diode and a second diode. The cathode of the first diode is connected to a +5V power supply, and the anode of the first diode and the cathode of the second diode are connected to the voltage / resistance measurement output terminal and the input terminal of the ground switching unit. The anode of the second diode is grounded.

5. The insulator voltage and resistance combined tester according to claim 4, characterized in that, The ground switching unit includes an analog switch, a voltage measurement grounding component, and a resistance measurement grounding component. Pins 1A and 2A of the analog switch are connected to the voltage / resistance measurement output terminal. Pin 1B of the analog switch is connected to the resistance measurement grounding component. Pin 2B of the analog switch is connected to the voltage measurement grounding component. Pin 1C of the analog switch is connected to the SWITCH_1 control output terminal of the first microcontroller. Pin 2C of the analog switch is connected to the SWITCH_2 control output terminal of the first microcontroller.

6. The insulator voltage and resistance combined tester according to claim 5, characterized in that, The voltage measurement grounding assembly includes a fifth resistor and a first capacitor. One end of the fifth resistor and the first capacitor is connected to pin 2B of the analog switch, and the other end of the fifth resistor and the first capacitor is grounded. The resistance of the fifth resistor is 1KΩ.

7. The insulator voltage and resistance combined tester according to claim 5, characterized in that, The resistance measurement grounding assembly includes a sixth resistor and a second capacitor. One end of the sixth resistor and the second capacitor are connected to pin 1B of the analog switch, and the other end of the sixth resistor and the second capacitor are grounded. The resistance of the sixth resistor is 15KΩ.

8. The insulator voltage and resistance combined tester according to claim 1, characterized in that, The amplifier circuit uses the AD8226 instrumentation amplifier.

9. The insulator voltage and resistance combined tester according to claim 1, characterized in that, The first microcontroller is an HC32L130J8TA-LQ48 MCU.

10. The insulator voltage and resistance combined tester according to claim 1, characterized in that, The wireless communication module uses a LoRa chip.

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