Rapid protection unit based on thyratron

Abstract

The utility model relates to the technical field of high-voltage test equipment, in particular to a rapid protection unit based on a thyratron, which comprises a power supply, a high-voltage signal, a power transformer T1, an adjustable voltage division circuit, a sharp pulse sampling circuit, the thyratron V1 and an alarm unit, a power transformer T1 is connected with a grid electrode of a thyratron V1 through an adjustable voltage division circuit, a cathode of the thyratron V1 is connected with a resistor R1 in series and is connected with the power transformer T1, an anode of the thyratron V1 is connected with an alarm unit circuit, the power transformer T1 is connected with a reset button SW1 in series and is connected with the alarm unit, and a high-voltage signal port is connected with a sharp pulse sampling circuit. The protection device is an important protection unit in high-voltage test equipment, and when discharge breakdown occurs in a test loop, the test loop needs to be rapidly cut off, so that the damage bearing time of a test object and the test equipment is shortened as much as possible, the test object and the test equipment are well protected, and the fault range is prevented from being further expanded.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage test equipment, in particular to a thyristor-based rapid protection unit. Background Art

[0002] With the development of science and technology, electrical equipment plays an increasingly important role in people's daily life and industrial production. However, when these devices are operating in a high-voltage environment, they may fail due to insufficient insulation performance, design defects or manufacturing defects, and even cause fire or electric shock accidents. Therefore, it is particularly important to conduct high-voltage withstand voltage tests on electrical equipment to evaluate its safety and stability in a high-voltage environment.

[0003] When conducting a high-voltage withstand test, the withstand voltage of the test product is much higher than the voltage when the test product is actually running. It is a destructive test. When a defective test product cannot withstand the test voltage, a breakdown failure will occur. At this time, the test circuit will be abnormal and need to be quickly disconnected. Therefore, a circuit protection unit is required. When a sharp jump in the test voltage is detected, the thyristor will act quickly to drive the intermediate relay, send a stop test signal, and close the test circuit. Utility Model Content

[0004] The purpose of the utility model is to provide a thyristor-based rapid protection unit to solve the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A thyristor-based fast protection unit comprises a power supply, a high-voltage signal input terminal, a power transformer T1, an adjustable voltage-dividing circuit, a sharp pulse sampling circuit, a thyristor V1 and an alarm unit, wherein the power supply is connected in series with the primary side of the power transformer T1, the power transformer T1 is connected to the gate of the thyristor V1 through the adjustable voltage-dividing circuit, the cathode series resistor R1 of the thyristor V1 is connected to the power transformer T1, the anode of the thyristor V1 is connected to the alarm unit circuit, the power transformer T1 is connected in series with a reset button SW1 and connected to the alarm unit, the high-voltage signal input terminal is connected to the sharp pulse sampling circuit, and the other port of the high-voltage signal input terminal is grounded.

[0007] Preferably, two groups of coils are connected in parallel to the secondary side of the power transformer T1. The first group of coils is connected in series with a diode D1 and an electrolytic capacitor C1 to provide power for the reset button SW1 and the intermediate relay K1, and the second group of coils directly provides heating power for the filament of the thyristor V1. One end of the other group of coils is grounded.

[0008] Preferably, the adjustable voltage divider circuit comprises a resistor R1 and a potentiometer PR1, the first group of coils of the power transformer T1 are connected in series with the resistor R1, the potentiometer PR1 and the resistor R2 and are connected to the gate of the thyristor V1, and the potentiometer PR1 is grounded.

[0009] Preferably, the spike sampling circuit comprises a capacitor C2, a resistor R3, a resistor R2 and a diode D2, and the high voltage signal input port is connected in series with the capacitor C2 and the resistor R3 and is connected to the gate of the thyristor V1.

[0010] Preferably, the alarm unit includes an intermediate relay K1 and an alarm output signal terminal, the anode of the thyristor V1 is connected in series with pin 1 of the intermediate relay K1, and pins 2, 3 and 4 of the intermediate relay K1 are respectively connected to interfaces reserved at the alarm output signal terminal.

[0011] Preferably, the first coil group of the power transformer T1 is connected in series with the diode D1 and the reset button SW1 and is connected to the pin 5 of the relay K1.

[0012] Compared with the prior art, the technical effects and advantages of the utility model are:

[0013] The utility model is an important protection unit in high-voltage test equipment and can be used in power frequency withstand voltage operating systems, frequency modulation or inductance modulation AC withstand voltage systems, etc. When a discharge breakdown occurs in the test circuit, real-time monitoring, abnormality detection, rapid disconnection and alarm indication are used to ensure that when an abnormal situation such as discharge breakdown occurs in the test circuit, the test circuit can be quickly disconnected, the time that the test product and the test equipment are damaged is reduced as much as possible, and the test product and the test equipment are effectively protected, the loss is reduced and the expansion of the fault range is prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0016] See also Figure 1 , the utility model provides a technical solution:

[0017] A thyristor-based fast protection unit comprises: a power supply, a high-voltage signal input terminal, a power transformer T1, an adjustable voltage-dividing circuit, a sharp pulse sampling circuit, a thyristor V1 and an alarm unit, wherein the power supply is connected in series with the primary side of the power transformer T1, the power transformer T1 is connected to the gate of the thyristor V1 through the adjustable voltage-dividing circuit, the cathode series resistor R1 of the thyristor V1 is connected to the power transformer T1, the anode of the thyristor V1 is connected to the alarm unit circuit, the power transformer T1 is connected in series with a reset button SW1 and connected to the alarm unit, the high-voltage signal input terminal is connected to the sharp pulse sampling circuit, and the other port of the high-voltage signal input terminal is grounded.

[0018] The power supply is converted into a voltage suitable for the circuit operation through the power transformer T1. The thyristor V1 is the core component of this circuit. When a flashover or breakdown fault occurs in the high-voltage test circuit, the abnormal sharp pulse in the high-voltage signal will be sent to the gate of the thyristor V1 through the sharp pulse sampling circuit, making the gate potential higher than the cathode potential, so that the anode and cathode of V1 are fully conductive. The conduction of the thyristor V1 causes the intermediate relay K1 connected in series with its anode to trigger an alarm signal. In order to reset the protection unit, the operator presses the reset button SW1, disconnects the power transformer T1 and the relay K1, and de-energizes the thyristor V1. After that, the protection unit returns to its original state and the high-voltage test can be performed again.

[0019] Specifically, two sets of coils are connected in parallel on the secondary side of the power transformer T1, which can provide two different output voltages or currents. The first set of coils provides a voltage of 110V, which is increased to about 140V through half-wave rectification by diode D1 and electrolytic capacitor C1. The reset button SW1 and the intermediate relay K1 provide power. The second set of coils provides a voltage of 6.3V, which directly provides heating power for the filament of the thyristor V1. One end of the second set of coils is grounded to ensure the safety and stability of the circuit.

[0020] Specifically, the adjustable voltage divider circuit includes a resistor R1 and a potentiometer PR1. The first group of coils of the power transformer T1 are connected in series with the resistor R1, the potentiometer PR1 and the resistor R2 and are connected to the gate of the thyristor V1. The potentiometer PR1 is grounded. The potentiometer PR1 needs to be adjusted to a position so that the voltage on the gate is 5V lower than that on the cathode. The action sensitivity of V1 can be changed by adjusting the potentiometer PR1.

[0021] Specifically, the spike pulse sampling circuit includes a capacitor C2, a resistor R3, a resistor R2 and a diode D2. A port of the high-voltage signal input end is connected in series with the capacitor C2 and the resistor R3 and is connected to the gate of the thyristor V1. When the test sample breaks down, the input voltage suddenly decreases, and a positive spike pulse is output to the gate of V1, forcing the anode and cathode of V1 to be turned on.

[0022] Specifically, the alarm unit includes an intermediate relay K1 and an alarm output signal terminal. The anode of the thyristor V1 is connected in series with pin 1 of the intermediate relay K1. Pin 2, pin 3, and pin 4 of the intermediate relay K1 are respectively connected to the interfaces reserved for the alarm output signal terminal. After the coil is energized, the state of the relay contact changes, and an alarm signal is given to close the high-voltage test circuit.

[0023] Specifically, the first group of coils of the power transformer T1 are connected in series with the diode D1 and the reset button SW1 and are connected to the pin 5 of the relay K1. When the thyristor V1 is turned on, the circuit unit always maintains the alarm state. Only when the reset button SW1 is pressed to disconnect its normally closed contact and the thyristor V1 is powered off, can the circuit be restored to its original state and be in the test state again.

[0024] The working principle of this embodiment is as follows:

[0025] When the high-voltage test circuit has no faults: the gate potential of the thyristor V1 is lower than the cathode, the gate blocks the movement of cathode electrons to the anode, V1 is open, the intermediate relay K1 remains in a normal state, and no alarm signal is output;

[0026] When the high-voltage test circuit flashes or breaks down: the V1 grid detects the ignition pulse signal, making the grid potential higher than the cathode, attracting and accelerating the cathode electrons to flow to the anode, causing the V1 anode-cathode to be fully conductive. At this time, the intermediate relay K1 is activated and sends an alarm signal to close the high-voltage test circuit. V1 is conductive, and K1 remains in the operating state;

[0027] Reset: After the fault action is detected, the fault alarm state is maintained. Only when the self-reset button SW1 is pressed, the conductive V1 is powered off and the alarm state is released. After releasing SW1, the circuit returns to its original state and is in the detection state.

[0028] The remaining parts not described in this utility model are existing or known technologies.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thyristor-based rapid protection unit, characterized in that: include: A power supply, a high-voltage signal input terminal, a power transformer T1, an adjustable voltage-dividing circuit, a sharp pulse sampling circuit, a thyristor V1 and an alarm unit, wherein the power supply is connected in series with the primary side of the power transformer T1, the power transformer T1 is connected to the gate of the thyristor V1 through the adjustable voltage-dividing circuit, the cathode series resistor R1 of the thyristor V1 is connected to the power transformer T1, the anode of the thyristor V1 is connected to the alarm unit circuit, the power transformer T1 is connected in series with the reset button SW1 and connected to the alarm unit, the high-voltage signal input terminal is connected to the sharp pulse sampling circuit, and the other port of the high-voltage signal input terminal is grounded.

2. The thyristor-based rapid protection unit according to claim 1, characterized in that: Two sets of coils are connected in parallel on the secondary side of the power transformer T1. The first set of coils is connected in series with a diode D1 and an electrolytic capacitor C1 to provide power for the reset button SW1 and the intermediate relay K1. The second set of coils directly provides heating power for the filament of the thyristor V1. One end of the second set of coils is grounded.

3. The thyristor-based rapid protection unit according to claim 2, characterized in that: The adjustable voltage divider circuit includes a resistor R1 and a potentiometer PR1. The first group of coils on the secondary side of the power transformer T1 are connected in series with the resistor R1, the potentiometer PR1 and the resistor R2 and are connected to the gate of the thyristor V1. The potentiometer PR1 is grounded.

4. The thyristor-based rapid protection unit according to claim 1, characterized in that: The sharp pulse sampling circuit includes a capacitor C2, a resistor R3, a resistor R2 and a diode D2. The high voltage signal input end one port is connected in series with the capacitor C2 and the resistor R3 and is connected to the gate of the thyristor V1.

5. The thyristor-based rapid protection unit according to claim 1, characterized in that: The alarm unit includes an intermediate relay K1 and an alarm output signal terminal. The anode of the thyristor V1 is connected in series with the pin 1 of the intermediate relay K1. The pins 2, 3 and 4 of the intermediate relay K1 are respectively connected to the interfaces reserved at the alarm output signal terminal.

6. The thyristor-based rapid protection unit according to claim 2, characterized in that: The first coil group on the secondary side of the power transformer T1 is connected in series with the diode D1 and the reset button SW1 and is connected to the pin 5 of the relay K1.

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