CN204408214U - A kind of pulse triggering means for spark gap protection - Google Patents

Abstract

The utility model patent discloses a kind of pulse triggering means for spark gap protection, comprises and drives resistance, triode, the first diode, the first transformer, the second diode, controllable silicon, storage capacitor and the second transformer.The low-voltage direct provided by external power source by the first transformer is converted to pulsation high pressure, is storage capacitor charging.Open-minded by controlling controllable silicon, and through the second transformer transformation, be that high voltage pulse exports by the power conversion be stored in electric capacity.Change the first load tap changer wiring and change the first transformer voltage ratio, thus change the charging voltage of storage capacitor, and then change the amplitude exporting high-voltage pulse.By reducing the inductance value of discharge loop stray inductance and the second transformer winding, it is the high-voltage pulse that spark gap protection provides a rising edge extremely short.The utility model patent structure is simple, and reliability is high, meets the actual conditions of engineering site.

Description

A pulse trigger device for spark gap protection

technical field

The utility model patent relates to the technical field of high voltage and high current, in particular to a pulse trigger device for spark gap protection.

Background technique

Spark gap is an overvoltage protection measure commonly used in power systems. The performance of spark gap directly affects the life of the protected equipment. The requirements for this type of spark gap are: high current, high voltage, short delay, frequent action, etc. After receiving the trigger signal from the protection system, the high-voltage pulse generated by the pulse trigger device is applied to the trigger electrode of the spark gap. Under the action of high-voltage pulse, the surface of trigger electrode and low-voltage electrode ignites and breaks down, and plasma is generated locally, which reduces the withstand voltage capacity of the spark gap. Under the action of external voltage, the spark gap breaks down to prevent the protected equipment from being damaged due to overvoltage .

In engineering applications, pulse trigger devices for spark gap protection have the following disadvantages:

First, there is no way to electrically isolate the pulse firing device from the spark gap. In this way, the pulse trigger device must be powered by an external power supply, such as solar power, laser power supply, ultrasonic power supply, microwave power supply, etc. The voltage generated by these power supply methods is often small, and the pulse trigger device needs to convert the energy accumulation under low voltage into high voltage pulse output.

Second, in order to shorten the breakdown delay of the spark gap, the pulse trigger device needs to generate a high-voltage pulse with a high amplitude and a very short rising edge, which puts high demands on the circuit design, especially the design of the inductance parameters . In order to make spark gap protection more widely used, it is urgent to design a pulse trigger device to solve the above problems.

Utility model patent content

The purpose of this utility model patent is to solve the above problems, providing a pulse trigger device for spark gap protection, which converts the energy accumulation under low voltage into a high-voltage pulse output with large amplitude and short rising edge to meet the spark gap Protection requirements for trigger sources.

In order to achieve the above object, the utility model patent adopts the following technical solutions:

A pulse trigger device for spark gap protection, comprising: a square wave signal source, a first transformer, a first diode, a second diode, an energy storage capacitor, a thyristor, and a second transformer;

The output end of the square wave signal source is connected to one end of the driving resistor, the other end of the driving resistor is connected to the base of the triode, the emitter of the triode is grounded, and the collector is connected to one end of the primary winding of the first transformer. The other end of the primary winding of the first transformer is connected to the power supply, and the two ends of the primary winding of the first transformer are connected in parallel with the first diode, and the cathode of the first diode is connected to the power supply terminal; the above-mentioned circuit constitutes the primary side of the first transformer discharge circuit;

One end of the secondary winding of the first transformer is connected to the anode of the second diode, one end of the secondary winding of the first transformer is connected to the anode of the second diode and the primary winding of the first transformer is connected to the anode of the first diode One end is the end with the same name;

The negative pole of the second diode is connected to one end of the energy storage capacitor, the other end of the energy storage capacitor is grounded and connected to one end of the primary winding of the second transformer, and the other end of the primary winding of the second transformer is connected to the first transformer. The other end of the secondary winding; the secondary winding of the second transformer outputs high-voltage pulses;

The cathode of the second diode is connected to the anode of the thyristor, the cathode of the thyristor is connected to the non-grounded end of the secondary winding of the first transformer, and the control electrode of the second diode is connected to the External trigger signal terminal connection.

The energy storage capacitor, the secondary winding of the first transformer, the second diode and the primary winding of the second transformer form a capacitor charging circuit; the thyristor, the energy storage capacitor and the secondary winding of the first transformer form a capacitor discharging circuit.

The square wave signal source is generated by a 555 timer.

Both the primary winding and the secondary winding of the first transformer have multiple taps for changing the transformation ratio of the first transformer.

The beneficial effects of the utility model patent are:

1. The utility model patent converts the low-voltage DC provided by the external power supply into a pulsating high voltage through the first transformer to charge the energy storage capacitor. The energy stored in the capacitor is converted into a pulsed high voltage output by controlling the thyristor to be turned on and passing through the second transformer. The structure is simple, the reliability is high, and it is in line with the actual situation of the engineering site.

2. The utility model patent adjusts the wiring of the tap of the first transformer, changes the number of turns of the primary winding and secondary winding of the first transformer, changes the transformation ratio of the first transformer, and then changes the charging voltage of the energy storage capacitor, which can be used for The trigger breakdown of spark gap protection provides pulse voltages with different amplitudes and energies to meet the actual needs of different sites.

3. The utility model patent reduces the stray inductance of the discharge circuit and processes the primary winding of the second transformer to control it within a few microhenries, so that a steep high-voltage pulse can be obtained with a very short rising edge.

Description of drawings

Fig. 1 is a structural schematic diagram of a pulse trigger device for spark gap protection;

In the figure, 1 is the square wave signal source, 2 is the triode, 3 is the driving resistor, 4 is the first diode, 5 is the first transformer, 6 is the second diode, 7 is the photoelectric isolation module, and 8 is the controllable Silicon, 9 is an energy storage capacitor, and 10 is a second transformer.

Detailed ways:

Below in conjunction with accompanying drawing and embodiment the utility model patent is described further:

As shown in Figure 1, a pulse trigger device for spark gap protection includes: a square wave signal source 1; the square wave signal source 1 is realized by a 555 timer, and the duty cycle of the square wave signal is changed by adjusting an external resistor The output end of the square wave signal source 1 is connected to one end of the drive resistor 3, the other end of the drive resistor 3 is connected to the base of the transistor 2, the emitter of the transistor 2 is grounded, and the collector is connected to one end of the primary winding of the first transformer 5, The other end of the primary winding of a transformer 5 is connected to the power supply, the two ends of the primary winding of the first transformer 5 are connected in parallel with the first diode 4, and the negative pole of the first diode 4 is connected to the power supply terminal; the above-mentioned circuit constitutes the primary side of the first transformer 5 discharge circuit;

One end of the secondary winding of the first transformer 5 is connected to the positive pole of the second diode 6, and one end of the secondary winding of the first transformer 5 is connected to the positive pole of the second diode 6 and the primary winding of the first transformer 5 is connected to the first diode One end of the positive pole of tube 4 is the end with the same name;

The negative pole of the second diode 6 is connected to one end of the energy storage capacitor 9, the other end of the energy storage capacitor 9 is grounded and connected to one end of the primary winding of the second transformer 10, and the other end of the primary winding of the second transformer 10 is connected to the first transformer 5. The other end of the secondary winding; the secondary winding of the second transformer 10 outputs high-voltage pulses;

The cathode of the second diode 6 is connected to the anode of the thyristor 8, and the cathode of the thyristor 8 is connected to the non-grounded end of the secondary winding of the first transformer 5, and the control pole of the second diode 6 is connected to the photoelectric isolation module 7 by External trigger signal terminal connection.

The energy storage capacitor 9 and the secondary winding of the first transformer 5, the second diode 6 and the primary winding of the second transformer 10 form a capacitor charging circuit; the thyristor 8, the energy storage capacitor 9 and the secondary winding of the first transformer 5 constitute Capacitor discharge circuit.

Both the primary winding and the secondary winding of the first transformer 5 have multiple taps for changing the transformation ratio of the first transformer 5 .

The triode used is provided by Shenzhen Mingjiada Electronics Co., Ltd., the model is BU406; the first diode and the second diode used are provided by Shenzhen Tegat Technology Co., Ltd., the model is 1N4148; the controllable The silicon is provided by Kaida Electronic Technology Co., Ltd., the model is MCR100; the photoelectric isolation module is 6N137 manufactured by Avago Technologies.

The operating principle and working process of the utility model patent are as follows:

The square wave signal source 1 generates a square wave with an adjustable duty cycle, which controls the triode 2 to be turned on and off periodically, and the driving resistor 3 is used to limit the driving current. When the triode 2 is turned on, the power supply terminal, the primary winding of the first transformer 5, and the triode 2 form a primary side discharge circuit, and a pulse current is generated in the primary winding of the first transformer 5, and then in the two secondary windings of the first transformer 5 A pulsed high voltage is generated at the end. By changing the tap connections of the first transformer 5 , the transformation ratio of the first transformer 5 is changed, thereby changing the charging voltage.

The pulse high voltage generated by the secondary winding of the first transformer 5 continuously charges the energy storage capacitor 9 until the voltage at both ends of the energy storage capacitor 9 is the same as the voltage at both ends of the secondary winding of the first transformer 5, and the charging ends. When the thyristor 8 receives an external trigger signal and conducts, the energy storage capacitor 9 discharges along the thyristor 8 and the primary winding of the second transformer 10, generating a pulse current in the primary winding of the second transformer 10, and then in the second A pulse high voltage is generated at both ends of the secondary winding of the transformer 10 . The ground potentials of the primary winding and the secondary winding of the first transformer 5 are different, and the potential difference is the voltage across the secondary winding of the first transformer 5 . The trigger signal needs to pass through a photoelectric isolation module 7 to isolate the two ground potentials.

Although the specific implementation of the utility model patent has been described above in conjunction with the accompanying drawings, it is not a limitation to the protection scope of the utility model patent. Those skilled in the art should understand that on the basis of the technical solution of the utility model patent, the technology in the field Various modifications or deformations that can be made by personnel without creative labor are still within the protection scope of the utility model patent.

Claims (3)

1., for a pulse triggering means for spark gap protection, it is characterized in that, comprising: square-wave signal source;

The output of described square-wave signal source connects the one end driving resistance, the base stage of the other end connecting triode of described driving resistance, the grounded emitter of described triode, collector electrode connects one end of a winding of the first transformer, the other end of a described first transformer winding connects power supply, two ends first diode in parallel of a described first transformer winding, the negative pole of described first diode connects power end; Foregoing circuit forms the primary side discharge loop of the first transformer;

One end of the secondary winding of described first transformer connects the positive pole of the second diode, and it is Same Name of Ends that the secondary winding of the first transformer connects one end of the second diode cathode and one end of the first transformer winding switching first diode cathode;

The negative pole of described second diode connects one end of storage capacitor, the other end ground connection of described storage capacitor and connect one end of the second transformer winding, the other end of a described second transformer winding connects the other end of the secondary winding of the first transformer; The secondary winding of described second transformer exports high-voltage pulse;

The negative pole of described second diode connects silicon controlled anode, and described silicon controlled negative electrode connects first earth-free one end of transformer secondary winding, and the control pole of described second diode is connected with outer triggering signal end by photoelectric isolation module.

2. as claimed in claim 1 a kind of for spark gap protection pulse triggering means, it is characterized in that, described square-wave signal source is produced by 555 timers.

3. as claimed in claim 1 a kind of for spark gap protection pulse triggering means, it is characterized in that, a winding of described first transformer and secondary winding have multiple tap, for changing the no-load voltage ratio of the first transformer.