Automatic detection system for direct-current breakdown voltage of gas discharge tube

Abstract

The invention relates to an automatic detection system for direct current breakdown voltage of a gas discharge tube, which comprises a main control circuit, a direct current impulse voltage ramp generation circuit used for generating direct current breakdown voltage of 0V-1000V, a six-path high-voltage dry reed relay circuit, a breakdown voltage detection circuit, and a terminal A, a terminal B and a terminal C which are used for connecting the gas discharge tube, the terminal A, the terminal B and the terminal C are respectively connected with three electrodes of the gas discharge tube, and the terminal C is suspended when the two-electrode gas discharge tube is tested; the second end of the first reed switch and the second end of the second reed switch of the six-way high-voltage reed relay are respectively connected with a terminal A, a terminal B and a terminal C to form six combinations of three electrodes of the gas discharge tube, wherein the three electrodes are sequentially ABACBABCACB pairwise; and the main control circuit is used for automatically switching the terminal A, the terminal B and the terminal C so as to realize automatic detection of the direct-current breakdown voltage of the gas discharge tube. The beneficial effect is that the direct current breakdown voltage between different electrodes of the gas discharge tube is detected without connecting the gas discharge tube to a circuit again.

Description

Technical field

[0001] The present invention relates to the technical field of lightning protection circuit detection, and in particular to an automatic detection system for the direct current breakdown voltage of a gas discharge tube. [Background Technology]

[0002] Gas discharge tubes (GDTs) are gap-type lightning protection components that play a vital role in overvoltage protection for electrical and electronic systems. To achieve effective protection, different GDTs are required for different circuits. Therefore, testing GDT parameters is particularly important, with DC breakdown voltage being one of the key parameters. Traditional GDT testing can lead to the following issues when manufacturers conduct batch testing of GDTs: Unexpected situations during testing require manual judgment regarding emergency shutdown, but manual operation may not always be timely, and high voltage electricity can pose a risk to equipment and personnel. Testing the DC breakdown voltage between different electrodes requires manual or machine adjustments to the GDT's placement for testing. The resulting data is voluminous, making manual classification and computer input cumbersome and inefficient.

[0003] A gas discharge tube (GDT) is a gap-type lightning protection component widely used in communication systems. It utilizes the principle of gas discharge to conduct under overvoltage conditions, dissipating instantaneous overcurrent from lightning, limiting overvoltage, and protecting electronic equipment connected in parallel from damage.

[0004] Gas discharge tubes are usually encapsulated in ceramic or glass and filled with an inert gas with stable electrical properties. Depending on the number of electrodes, they can be divided into diode discharge tubes and triode discharge tubes:

[0005] Diode discharge tube: consists of two electrodes (A and B) and has a relatively simple structure.

[0006] Triode discharge tube: consists of three electrodes (A, B, C), one of which serves as a grounding electrode to provide better grounding effect and discharge performance.

[0007] Reed Relay is an electronic device based on magnetic materials, mainly used in automatic control and protection circuits.

[0008] Basic composition:

[0009] Reed switch: The core component of a reed relay, it consists of two parallel, magnetically conductive reeds enclosed in a glass tube filled with an inert gas (such as helium or nitrogen). The ends of the reeds overlap with a gap. When an external magnetic field is applied, the reeds become magnetized and attract or repel each other.

[0010] Excitation coil (or permanent magnet): used to generate a magnetic field to control the opening and closing state of the reed switch.

[0011] Working principle:

[0012] When the excitation coil is energized (or a permanent magnet is placed close to the reed switch), a magnetic field is generated inside and around the coil, causing the reeds in the reed switch to become magnetized and attract each other, causing the reeds to touch and the circuit to be connected.

[0013] When the excitation coil is de-energized (or the permanent magnet is away from the reed switch), the magnetic field disappears, the reed returns to its original position by its own elasticity, the reed separates, and the circuit is disconnected.

[0014] The present invention addresses the technical problems in traditional detection, such as cumbersome operation, inability to automatically perform emergency shutdown, the need to reconnect the gas discharge tube to the circuit when detecting the DC breakdown voltage between different electrodes of the gas discharge tube, and the inability to efficiently analyze data. The invention provides a technical improvement to the automatic detection system for the DC breakdown voltage of the gas discharge tube. [Summary of the invention]

[0015] The purpose of the present invention is to provide a gas discharge tube DC breakdown voltage automatic detection system which detects the DC breakdown voltage between different electrodes of the gas discharge tube without reconnecting the gas discharge tube to the circuit.

[0016] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is a gas discharge tube DC breakdown voltage automatic detection system, including a main control circuit, a DC impulse voltage ramp generating circuit for generating a 0V-1000V DC breakdown voltage, a six-way high-voltage reed relay circuit, and a breakdown voltage detection circuit, which is used to connect the A terminal, B terminal, and C terminal of the gas discharge tube, wherein the A terminal, B terminal, and C terminal are respectively connected to the three electrodes of the gas discharge tube, and the C terminal is left floating when testing the two-electrode gas discharge tube; the high-voltage reed relay includes a first reed switch, a second reed switch, an excitation coil for controlling the opening and closing of the first reed switch and the second reed switch, and a photoelectric coupler for controlling the magnetic field generated by the excitation coil, and the second end of the first reed switch and the second reed switch of the six-way high-voltage reed relay are respectively connected to the A terminal, the B terminal, and the C terminal. The three electrodes of the gas discharge tube are arranged in six combinations of the order AB\AC\BA\BC\CA\CB. The first end of the first reed switch of the six-way high-voltage reed relay is connected to the output of the DC impulse voltage ramp-up generating circuit, and the first end of the second reed switch of the six-way high-voltage reed relay is connected to the input of the breakdown voltage detection circuit. The main control circuit is used to control the DC impulse voltage ramp-up generating circuit to generate a detection high voltage, control the on and off of the photoelectric coupler, collect the breakdown voltage returned by the breakdown voltage detection circuit, and control the connection state of the six-way high-voltage reed relay to output the three electrodes of the gas discharge tube in six combinations of the order AB\AC\BA\BC\CA\CB, and automatically switch the A terminal, the B terminal, and the C terminal to realize the automatic detection of the DC breakdown voltage of the gas discharge tube. The automatic switching of the six configurations of the reed relay is indirectly controlled by connecting a specific output pin of the MCU to the optocoupler circuit.

[0017] Preferably, the automatic detection system for the DC breakdown voltage of a gas discharge tube uses optocoupler isolation and trenching to electrically isolate the DC breakdown voltage of the gas discharge tube from the low-voltage power supply.

[0018] Preferably, the main control circuit is an ARM-based MCU, and the main control circuit includes a data storage module for storing detection data.

[0019] Preferably, the breakdown voltage detection circuit includes a high-voltage attenuation probe for attenuating the breakdown voltage and an ADC sampler for ADC sampling.

[0020] Preferably, when the DC impulse voltage ramp-up generating circuit generates the DC breakdown voltage of the gas discharge tube, it is necessary to first implement 0V-1000V voltage regulation through a digital potentiometer combined with a 24V power supply and an isolated power supply module to complete the preparation of preliminary conditions, and then further adjust the slope of the voltage rise by switching the resistor and capacitor through a relay to obtain a 5-speed DC impulse voltage ramp-up generating circuit for testing the DC breakdown voltage of the gas discharge tube.

[0021] The present invention provides a gas discharge tube DC breakdown voltage automatic detection system with the following beneficial effects: the system highly integrates circuits with various functions and uses an ARM-based MCU, relays, etc. to connect them, thereby realizing automatic detection of the gas discharge tube DC breakdown voltage and achieving a simple and efficient gas discharge tube automatic detection function.

Brief Description of the Drawings

[0022] Figure 1 The present invention is a flow chart of the operation of an automatic detection system for DC breakdown voltage of a gas discharge tube.

[0023] Figure 2 This is a schematic diagram of six connection methods of reed relays in a gas discharge tube DC breakdown voltage automatic detection system.

[0024] Figure 3 The invention relates to an automatic sorting system for detecting whether the DC breakdown voltage of a gas discharge tube is qualified.

[0025] Figure 4 It is an optocoupler circuit used by MCU to indirectly control 6 configurations of reed relays.

[0026] Figure 5 It is a circuit that completes 0-1000V voltage regulation

[0027] Figure 6 It is a 5-speed DC impulse voltage ramp generating circuit

[0028] Figure 7 It is the circuit collected by ADC [Specific implementation method]

[0029] The present invention will be further described below in conjunction with embodiments and with reference to the accompanying drawings.

[0030] Example 1

[0031] This embodiment provides an automatic detection system for the DC breakdown voltage of a gas discharge tube, which overcomes the problems of cumbersome operation in traditional detection, the inability to automatically shut down in an emergency, the need to reconnect the gas discharge tube to the circuit to detect the DC breakdown voltage between different electrodes of the gas discharge tube, and the inability to efficiently analyze data.

[0032] In this embodiment, a system for automatically detecting the DC breakdown voltage of a gas discharge tube includes a main control circuit, a detection circuit, a power supply circuit, data acquisition, and high-voltage isolation. The main control circuit is an ARM-based MCU, and the relay part connected to the main control circuit includes an intermediate relay, a high-voltage reed relay, and a high-voltage, high-current relay. At the beginning of the test, the high-voltage reed relay connects to the corresponding test power supply and test circuit. The detection circuit obtains the test result of the DC breakdown voltage after attenuation through a high-voltage attenuation probe. The power supply circuit includes a power supply for testing the DC breakdown voltage and some power supplies for other circuits. The test results are sampled by the ADC on the MCU, and the sampling results are analyzed. Because the DC breakdown voltage detection of the gas discharge tube requires high voltage and other circuits require low voltage power supply, this system also uses optocoupler isolation and trenching methods for electrical isolation.

[0033] To achieve the above-mentioned purpose, this embodiment provides an automatic detection system for the DC breakdown voltage of a gas discharge tube, comprising:

[0034] The ARM-based MCU serves as the main control circuit, executing program instructions and processing data. It integrates multiple functional modules, enabling the selection of test electrodes and control of test cessation by controlling the output potential. This eliminates the problem of cumbersome operation and enables emergency shutdown. Test results are also fed back to the MCU, eliminating the need for manual data analysis or input into a computer. The main control circuit also has a storage function for data. The main control chip is powered by a 3.3V supply voltage, and a nearby voltage-regulated output circuit converts the 5V input voltage into a 3.3V output voltage.

[0035] The MCU output is connected to one end of an optocoupler isolation circuit, the other end of which is connected to an intermediate relay, a high-voltage reed relay, and a 5-position DC impulse voltage ramp circuit. The optocoupler isolation circuit and each relay act as a "switches," controlled by the potential of the circuit connecting them.

[0036] The high-voltage reed relay circuit is used to select test content and six test configurations. The other end of the high-voltage reed relay circuit is connected to a circuit for testing DC breakdown voltage. This connection creates six output detection voltage configurations. These six configurations represent sequential pairwise combinations of the three electrodes of the gas discharge tube (AB, AC, BA, BC, CA, and CB). Therefore, when testing the DC breakdown voltage between different electrodes of the gas discharge tube, the circuit can be switched simply using an optocoupler and relay, eliminating the need to reconnect the gas discharge tube. This automated switching is achieved by using optocouplers and relays to control circuit connection and switching by changing potential. Automatic switching of the reed relay circuit's six configurations is indirectly controlled by connecting a specific MCU output pin to the optocoupler circuit.

[0037] When detecting the DC breakdown voltage of the gas discharge tube, a national standard DC breakdown voltage test circuit is used; a digital potentiometer is used in combination with a power supply to achieve 0-1KV voltage regulation; the resistor and capacitor are switched by a relay, and the slope of the voltage rise can be adjusted to obtain a 5-speed DC impulse voltage ramp circuit for testing the DC breakdown voltage.

[0038] The obtained DC breakdown voltage is attenuated using a high-voltage attenuation probe, and then data is collected. The data is collected using an ADC with a 16-bit sampling bit and a sampling frequency of 1 kHz on the MCU. The ARM-based MCU will analyze the sampling results.

[0039] Because the test voltage is high, while the chip only requires a 3.3V supply voltage, and other circuits have different operating voltages, voltage isolation is essential for integrating these components. The optocoupler isolation circuit used in this system can achieve high- and low-voltage isolation. Furthermore, some adjacent circuit modules may have significant voltage differences. To prevent breakdown, trenches can be cut between them for isolation.

[0040] Specifically:

[0041] Figure 1 This is a flow chart of the automatic detection system for DC breakdown voltage of gas discharge tubes. Figure 1 As shown in the figure, the system operation process of this embodiment allows the user to control the entire test by simply issuing instructions to the ARM-based MCU. Specifically, the MCU controls the optocoupler and relay, indirectly selecting a five-position DC impulse voltage ramp circuit for testing the DC breakdown voltage, selecting the test electrode, attenuating the test voltage before testing, sampling using the ADC on the MCU, and analyzing and processing the sampling results, thus achieving automation.

[0042] Figure 2 This is a schematic diagram of 6 configurations of reed relay circuits in a gas discharge tube DC breakdown voltage automatic detection system. Figure 2 As shown in the figure, the reed relay circuit of this embodiment is connected in six configurations. The reed relay circuit controls the output test voltage in six configurations, namely, A, B, and C, which are sequentially combined in pairs. A, B, and C represent the test voltages output to the three electrodes of the GDT, respectively. When testing a two-electrode gas discharge tube (GDT), the C terminal is left floating. By controlling the connection state of the reed relay circuit, the connection state of the test electrode can be controlled, achieving automatic switching of the test electrode and avoiding the tedious operation of reconnecting the GDT to the circuit.

[0043] Figure 3The invention is an automatic sorting system for detecting whether the DC breakdown voltage of gas discharge tubes is qualified. Figure 3 As shown, a specific example of use is given. An automatic detection system for the DC breakdown voltage of a gas discharge tube provided in this embodiment is installed in the device, and combined with a certain algorithm to achieve the purpose of automatically detecting whether the parameters of the DC breakdown voltage of the gas discharge tube are qualified and sorting. A, B, and C connected to the high-voltage reed relay are now connected to the three pins in the device, which are used to connect the various electrodes and detection circuits of the gas discharge tube. At the beginning of the test, the ARM-based MCU sends instructions to control the machine to load the material. At this time, the DC breakdown voltage generation circuit of the gas discharge tube is connected. By controlling each relay, the gas discharge tube is connected to the corresponding circuit for testing. The DC breakdown voltage measurement circuit is connected. After the DC breakdown voltage obtained by the test is attenuated by the high-voltage attenuation probe, the data is collected by ADC, and the sampling results are analyzed and processed to determine whether its quality is qualified and sorted.

[0044] Figure 4 This is an optocoupler circuit used by an MCU to indirectly control six configurations of reed relays. One end of the optocoupler circuit is RL1, RL2, RL3, RL4, RL5, RL6, or RL8, which is connected to the reed switch to control whether the reed switch is connected in the corresponding configuration. Automatic switching can be achieved by burning the control program into the MCU.

[0045] Figure 5 It is a 0-1000V voltage regulation, which is a preliminary preparation for the ramp-up circuit. The DC-DC power supply module can output a 0-1000V linear adjustable voltage. The switching power supply provides a 24V DC input, which is filtered before inputting the power supply module. The power supply module combines with the digital potentiometer to complete the 0-1000V voltage regulation. The digital potentiometer and the analog circuit need to pass through an isolated power supply module to prevent strong and weak signals from interfering with each other. After the 0-1000V voltage regulation is completed, the output high voltage is connected in series to the DC impulse voltage ramp-up circuit. Figure 6 In the middle label HV1--.

[0046] Figure 6 This is a 5-position DC impulse voltage ramp-up circuit. Combined with the power supply, the voltage rise slope is adjusted by switching the resistor and capacitor through the relay. The voltage rise slope is related to the time constant τ. The time constant can be calculated according to the formula τ=RC. In the first-order RC circuit, the voltage can be calculated according to the formula Calculate the voltage, so each relay is connected to a different resistance value, while the capacitance remains unchanged, which can change the slope of the voltage rise; the purpose of connecting 4 parallel resistors before the high voltage output is to limit the current. In the figure, R1, R2, R3, and R4 are connected in parallel according to the formula The equivalent resistance R can be calculated to be 50KΩ. However, since the power consumption of a 50KΩ resistor is relatively large and it is easy to burn out the resistor, four 200KΩ resistors in parallel are used to limit the current. For example, when the voltage at the hv label is 1000V, according to the formula The calculated power of a 50KΩ resistor is 20W, which is a relatively large value, while the power of a 200KΩ resistor is 5W, which is a more appropriate size.

[0047] Figure 7 It is an ADC acquisition circuit used to detect breakdown voltage. When the gas discharge tube breaks down, the breakdown voltage is connected to the high-voltage attenuation probe through the high-voltage reed relay. The attenuated voltage is filtered by RC and then connected to the ADC port of the MCU for data acquisition.

[0048] In summary, the system highly integrates circuits of various functions and uses ARM-based MCU, relays, etc. to connect them, thereby realizing the automatic detection of the DC breakdown voltage of the gas discharge tube and realizing the automatic detection function of the gas discharge tube with simple operation and high efficiency.

[0049] Those skilled in the art will appreciate that all or part of the steps for implementing the above embodiments may be accomplished by hardware, or may be accomplished by a program instructing the relevant hardware, and the program may be stored in a computer-readable storage medium, wherein the storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the principles of the present invention. These improvements and supplements should also be regarded as the scope of protection of the present invention.

Claims

1. A gas discharge tube DC breakdown voltage automatic detection system, characterized by: The invention comprises a main control circuit, a DC impulse voltage ramp generating circuit for generating a 0-1000V DC breakdown voltage, a six-way high-voltage reed relay circuit, and a breakdown voltage detection circuit, which is used to connect the A terminal, B terminal, and C terminal of a gas discharge tube. The A terminal, B terminal, and C terminal are respectively connected to the three electrodes of the gas discharge tube. When testing the two-electrode gas discharge tube, the C terminal is left floating. The high-voltage reed relay circuit comprises a first reed switch, a second reed switch, an excitation coil for controlling the opening and closing of the first reed switch and the second reed switch, and a photoelectric coupler for controlling the magnetic field generated by the excitation coil. The second end of the first reed switch and the second reed switch of the six-way high-voltage reed relay circuit are respectively connected to the A terminal, the B terminal, and the C terminal, forming the three electrodes of the gas discharge tube in the order of AB\A. The six combinations of C\BA\BC\CA\CB are provided, the first end of the first reed switch of the six-way high-voltage reed relay circuit is connected to the output of the DC impulse voltage ramp-up generating circuit, and the first end of the second reed switch of the six-way high-voltage reed relay circuit is connected to the input of the breakdown voltage detection circuit; the main control circuit is used to control the DC impulse voltage ramp-up generating circuit to generate a detection high voltage, control the on and off of the photoelectric coupler, collect the breakdown voltage returned by the breakdown voltage detection circuit, and control the connection state of the six-way high-voltage reed relay to output the three electrodes of the gas discharge tube in pairs in the order of AB\AC\BA\BC\CA\CB, and automatically switch the A terminal, B terminal, and C terminal to realize automatic detection of the DC breakdown voltage of the gas discharge tube.

2. The automatic detection system for DC breakdown voltage of a gas discharge tube according to claim 1, characterized in that: Optocoupler isolation and trenching are used to electrically isolate the DC breakdown voltage of the gas discharge tube from the low-voltage power supply.

3. The automatic detection system for DC breakdown voltage of a gas discharge tube according to claim 1, characterized in that: The main control circuit is an ARM-based MCU, and the main control circuit includes a data storage module for storing detection data.

4. The automatic detection system for DC breakdown voltage of a gas discharge tube according to claim 1, characterized in that: The breakdown voltage detection circuit includes a high-voltage attenuation probe for attenuating the breakdown voltage and an ADC sampler for ADC sampling.

5. The automatic detection system for DC breakdown voltage of a gas discharge tube according to claim 1, characterized in that: When the DC impulse voltage ramp-up generating circuit generates the DC breakdown voltage of the gas discharge tube, a digital potentiometer is used in combination with a power supply to achieve voltage regulation from 0V to 1000V. The slope of the voltage rise is adjusted by switching the resistor and capacitor through a relay, thereby obtaining a five-speed DC impulse voltage ramp-up circuit for testing the DC breakdown voltage of the gas discharge tube.

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