CN219875698U

CN219875698U - Multistage marx circuit with primary acceleration trigger and pulse power system

Info

Publication number: CN219875698U
Application number: CN202320787797.9U
Authority: CN
Inventors: 温凯俊; 项卫光
Original assignee: Wuhan Pulse Core Electronic Technology Co ltd
Current assignee: Wuhan Pulse Core Electronic Technology Co ltd
Priority date: 2023-04-11
Filing date: 2023-04-11
Publication date: 2023-10-20
Anticipated expiration: 2033-04-11

Abstract

The utility model discloses a multistage marx circuit with primary acceleration triggering and a pulse power system, comprising: a primary acceleration circuit comprising a DSRD, a DSRD trigger circuit and an avalanche transistor ABJT1; the marx circuits comprise avalanche transistors ABJT 2-ABJTn, pulse load resistors Rs 2-Rsn and current-limiting resistors Rx 2-Rxn; the primary acceleration circuit is used for applying a high-speed trigger pulse to both the emitter and the collector of the avalanche transistor ABJT1 by utilizing the quick turn-off capability of the DSRD, so that the avalanche transistor ABJT1 is quickly over-voltage turned on, and the quick trigger pulse is generated to the avalanche transistor ABJT2. The utility model can avoid large-area damage of the ABJT2 in the marx circuit caused by uneven triggering, and effectively improves the use reliability of the ABJT 2-ABJTn in the marx circuit.

Description

Multistage marx circuit with primary acceleration trigger and pulse power system

Technical Field

The utility model belongs to the technical field of pulse power circuits, and particularly relates to a multistage marx circuit with primary acceleration triggering and a pulse power system.

Background

The pulsed power technique first stores electrical energy at a low power and then releases the energy to the load through a switch, a transmission loop, etc. in a short time, thereby obtaining a high pulsed power on the load. Part of the pulse power technology was developed due to defense requirements, including: rail cannon, electromagnetic stealth technology, ground penetrating radar, impact radar, electromagnetic countermeasure, and the like. Pulse power technology has a very important characteristic requirement for pulse power systems, and a fast pulse technology with a steep rising front and a narrow pulse width is required.

Avalanche transistor ABJT (Avalanche Bipolar Junction Transistor) is a novel ultra-high speed, fast-forward semiconductor pulse power device for ns-and ps-stage pulse power systems that can provide extremely high switching speeds and can produce high peak power pulses with subns and even ps-stage rising edges. In addition, the marx circuit based on ABJT triggers ABJT in the first stage, and the subsequent ABJT turns on its overvoltage breakdown due to the voltage overshoot across the collector-emitter. Because the whole size of the ABJT device is smaller, the marx circuit formed by the ABJT has good integration and is easy to trigger and control, and the pulse with the amplitude far higher than the power supply voltage can be generated, so that the device is widely applied to students at home and abroad.

A Drift Step Recovery Diode (DSRD) is an open-circuit pulsed power switch with a switching speed on the order of nanoseconds. The DSRD has simple structure, high current capacity, high voltage withstanding and high repetition frequency, and the pulse generating circuit based on the DSRD has simple structure, so the DSRD is widely applied to the field of pulse power, such as ground penetrating radar, ultra-fast beam emitters, accelerators and the like.

As shown in fig. 1, a conventional marx circuit is known. In the practical application process, it is found that when the marx circuit based on the ABJT works at the heavy frequency, after the base electrode of the first stage ABJT in the marx circuit is triggered, the opening speed is slower, so that the slow dv/dt trigger occurs on the ABJT of the second stage, the opening area of the device is smaller, the current wire effect is more obvious, and the device is easier to thermally damage. After the thermal damage of the second stage ABJT becomes a short-circuit point, due to the specificity of the marx circuit structure, dv/dt of triggering of the third stage ABJT is reduced, and the thermal damage phenomenon is continuously diffused from the second stage to the subsequent stage. Therefore, how to fundamentally solve the thermal damage phenomenon in the second stage ABJT2 during the process of generating the repetition frequency pulse by the marx circuit, and the current situation that the device is damaged step by step due to the thermal damage transmitted from the second stage are important problems.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model aims to provide a multistage marx circuit with primary acceleration triggering and a pulse power system, which aim to fundamentally solve the irreversible process that under the high-frequency repeated pulse working condition, the heat damage of a snowburst transistor in a second stage branch occurs and the heat damage of a snowburst transistor device in a subsequent stage circuit step by step is caused.

To achieve the above object, in a first aspect, the present utility model provides a multi-stage marx circuit with primary acceleration triggering, including a primary acceleration circuit and a plurality of unipolar marx circuits, the primary acceleration circuit including a drift step recovery diode DSRD, a DSRD trigger circuit, and an avalanche transistor ABJT1;

the single-pole marx circuits are positioned at the 2 nd-n th level in the multi-level marx circuits, the multiple marx circuits are connected with avalanche transistors ABJT 2-ABJTn and pulse load resistors Rs 2-Rsn, the collector of the avalanche transistor ABJT1 is connected with the base and the emitter of the avalanche transistor ABJT2 through a capacitor C1, each single-pole circuit is connected with a high-voltage direct current power supply DC2 after being connected with a current limiting resistor Rx 2-Rxn in series, adjacent single-pole circuits are correspondingly connected through capacitors C2-Cn, and the capacitor Cn is grounded through a load RL; the primary acceleration circuit is configured to apply a high-speed trigger pulse to both the emitter and collector of the avalanche transistor ABJT1 using the fast turn-off capability of the drift step recovery diode DSRD, so that the avalanche transistor ABJT1 is turned on quickly by overvoltage, and to generate a fast trigger pulse to the avalanche transistor ABJT2.

The multistage Marx circuit with the primary acceleration trigger, provided by the utility model, is applied to a conventional multistage Marx circuit with frequent thermal damage, can effectively ensure the high-efficiency working state of the ABJT2 in the second branch from the circuit structure angle, fundamentally avoids the thermal damage problem of the ABJT2 caused by uneven triggering of slower voltage pulses, effectively solves the irreversible process of the Marx circuit caused by the thermal damage of the ABJT2 and the gradual damage of the circuit, and improves the use reliability of the ABJT 2-ABJTn in the Marx circuit.

In one embodiment, the DSRD trigger circuit includes a power switch Q1, a high voltage DC power supply DC1, a magnetic saturation transformer Tr, and current limiting resistors R and Rx1;

one end of a primary coil of the magnetic saturation transformer Tr is connected with a collector of the power switch Q1 and one end of a current limiting resistor R through an inductor L and a capacitor CO1 respectively, the other end of the current limiting resistor R is connected with a positive electrode of the high-voltage direct-current power supply DC1, and an emitter of the power switch Q1 and the other end of the primary coil of the magnetic saturation transformer Tr are connected with a negative electrode of the high-voltage direct-current power supply DC1 respectively; one end of a secondary coil of the magnetic saturation transformer Tr is respectively connected with the anode of the drift step recovery diode DSRD, the base electrode and the emitter of the avalanche transistor ABJT1 through a capacitor C02, and the cathode of the drift step recovery diode DSRD is grounded; one end of the current limiting resistor Rx1 is connected with the positive electrode of the high-voltage direct-current power supply DC2, and the other end of the current limiting resistor Rx1 is grounded through a capacitor C03.

In one embodiment, the number of stages of the multi-stage marx circuit is 5 to 30 stages.

In one embodiment, the power switch Q1 employs a field effect transistor.

In a second aspect, the present utility model provides a pulse power system comprising a multistage marx circuit with primary acceleration triggering as described above.

Drawings

FIG. 1 is a circuit schematic of a conventional marx circuit;

fig. 2 is a schematic circuit diagram of a multi-stage marx circuit with primary acceleration triggering according to an embodiment of the present utility model.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Fig. 1 is a schematic circuit diagram of a conventional marx circuit, as shown in fig. 1, in the charging process, the entire marx circuit charges pulse discharge capacitors C (1-n) through current-limiting resistors Rx (1-n) by a high-voltage power supply DC, so that avalanche transistors ABJT (1-n) operate in a critical avalanche region. In the working process of the marx circuit, firstly, a trigger circuit QD triggers the ABJT1 to be opened, a capacitor C1 discharges through the ABJT1 to form a loop C1-ABJT1-Rs2-C1, negative pulses are generated on the Rs2, so that voltage slopes of slow dv/dt are generated on the ABJT2, two ends of the ABJT2 exceed a certain voltage withstand value, then overvoltage opening is performed, C2 and C1 are serially discharged to form a loop C2-ABJT2-C1-ABJT1-Rs3-C2, negative pulses are generated on the Rs3, so that voltage slopes of fast dv/dt are generated on the ABJT3, two ends of the ABJT3 exceed a certain voltage withstand value, the rest ABJT (4-n) are sequentially opened, the capacitors C (1-n) are serially discharged, and finally voltage pulses are generated on a load RL, and one-time pulse discharging is completed. When the pulse is repeated, as the ABJT2 is repeatedly triggered by the slow dv/dt, the device is partially turned on to form destructive current wires, and the natural heat dissipation time is insufficient, so that the ABJT2 is extremely easy to thermally damage under the heavy frequency pulse working condition, and the marx circuit based on the ABJT does not have the reliability under the heavy frequency working condition.

Fig. 2 is a schematic diagram of a multi-level marx circuit with primary acceleration triggering according to an embodiment of the present utility model, and as shown in fig. 2, the multi-level marx circuit includes a primary acceleration circuit and a plurality of monopole marx circuits cascaded in sequence. It should be noted that the number of stages of the multi-stage marx circuit provided in this embodiment may be cascaded according to the pulse peak requirement, for example, 5-30 stages, which is not limited in this embodiment.

The multi-stage marx circuit comprises a plurality of monopole marx circuits, a plurality of pulse load resistors, a plurality of single-pole marx circuits, a plurality of pulse load resistors, a plurality of current limiting resistors, a plurality of capacitors, a plurality of current limiting resistors, a plurality of capacitors and a pulse load resistor, wherein the monopole marx circuits are located at the 2 nd-n stages in the multi-stage marx circuit, and the circuit structure of the monopole marx circuits is connected with the circuit structure of the 2 nd-n stages marx circuits in the traditional marx circuit. The marx circuits are connected with avalanche transistors ABJT 2-ABJTn and pulse load resistors Rs (2-n), each single-stage circuit is connected with a high-voltage direct-current power supply DC2 after being connected with current limiting resistors Rx 2-Rxn in series, adjacent single-stage circuits are correspondingly connected through capacitors C2-Cn, and the capacitor Cn is grounded through a load RL.

The primary acceleration circuit comprises a trigger circuit of drift step recovery diodes DSRD, DSRD and an avalanche transistor ABJT1, the collector of the avalanche transistor ABJT1 being connected to the base and emitter of the avalanche transistor ABJT2 via a capacitor C1.

In this embodiment, considering that in the conventional multilevel marx circuit, the avalanche transistor ABJT1 of the first level is triggered by the base, the turn-on speed thereof is about 10 times slower than that of the avalanche transistors ABJT2 to ABJTn of the subsequent level, which results in that the trigger pulse applied to ABTJ2 is more gentle than ABTJ3 to ABJTn, which results in uneven turn-on of ABTJ2 and frequent thermal damage. Therefore, the primary accelerating circuit provided in this embodiment applies trigger pulses with ultra-fast front edges generated by using the fast turn-off capability of DSRD to both ends of the emitter and collector of ABJT1, so that ABJT1 is turned on quickly in overvoltage, and fast trigger pulses are generated to ABJT2, so that ABJT2 to ABJTn are turned on in sequence until the capacitors C1 to Cn are discharged in series and finally on load R in the case that ABJT1 is triggered by the latter marx circuit _L The voltage pulse is generated, so that large-area damage of the ABJT2 in the marx circuit caused by uneven triggering can be avoided, and the use reliability of the ABJT 2-ABJTn in the marx circuit is effectively improved.

Specifically, the trigger circuit of DSRD provided in this embodiment may use a constituent circuit of the power switch Q1, the high-voltage direct-current power supply DC1, the magnetic saturation transformer Tr, and the current limiting resistors R and Rx 1. The connection relation of each device is as follows: one end of a primary coil of the magnetic saturation transformer Tr is connected with a collector electrode of the power switch Q1 and one end of a resistor R respectively through an inductor L and a capacitor CO1 in sequence, the other end of the resistor R is connected with a positive electrode of the high-voltage direct-current power supply DC1, and an emitter electrode of the power switch Q1 and the other end of the primary coil of the magnetic saturation transformer Tr are both connected with a negative electrode of the external high-voltage direct-current power supply DC 1; one end of a secondary coil of the magnetic saturation transformer Tr is respectively connected with the anode of the drift step recovery diode DSRD, the base electrode and the emitter of the avalanche transistor ABJT1 through a capacitor C02, and the cathode of the drift step recovery diode DSRD is grounded; one end of the current-limiting resistor Rx1 is connected with the positive electrode of the high-voltage direct-current power supply DC2, and the other end of the current-limiting resistor Rx1 is grounded through a capacitor C03. Specifically, the power switch Q1 provided in the present embodiment may employ a field effect transistor.

The working principle of the multistage marx circuit with primary acceleration triggering based on the trigger circuit structure of DSRD is as follows:

in the charging process, the high-voltage direct-current power supply DC1 charges a capacitor C01 in the primary accelerating circuit through a current-limiting resistor R, and the high-voltage direct-current power supply DC2 charges pulse discharging capacitors C (1-n) and C03 through current-limiting resistors Rx (1-n), so that ABJT (1-n) works in a critical avalanche region.

The whole marx circuit works under the heavy frequency working condition, the high-voltage direct current power supplies DC1 and DC2 are normally powered, the power switch Q1 is triggered to be turned on, the capacitor C01 is discharged to form a loop C01-Q1-Tr-L-C01, the capacitor C02 is charged by a charging loop Tr-C02-DSRD-Tr formed by the magnetic saturation transformer Tr, and at the moment, the drift step recovery diode DSRD is conducted and pumped in the forward direction. Due to the magnetic saturation process of the magnetic saturation transformer Tr core, the capacitor C02 is charged to stop and start to form a reverse discharge loop C02-Tr-DSRD-C02 and extract carriers in DSRD to cause DSRD to be rapidly turned off, so that the capacitor C02 and C03 are serially discharged to form a rapid high-voltage pulse loop C02-Tr-C03-ABJT1-C02, and rapid high-voltage pulses are applied to two ends of a collector and an emitter of the avalanche transistor ABJT1 to cause the ABJT1 to be rapidly overvoltage-turned on. After ABJT1 is turned on, capacitor C1 discharges to form loop C1-ABJT1-C02-Tr-Rs2-C1, and high-speed pulse is formed on current limiting resistor Rs2 and applied to both ends of collector and emitter of avalanche transistor ABJT2, so that ABJT2 is turned on rapidly, and capacitor C2 and C1 discharge in series to form loop C2-ABJT2-C1-ABJT1-C02-Tr-Rs3-C2 so that subsequent stages ABJT 3-ABJTn are conducted in this way, and finally capacitor C02 and C1-Cn discharge in series and form high-voltage pulse on load RL.

The multistage Marx circuit with primary acceleration triggering, which is provided by the embodiment, is applied to a conventional multistage Marx circuit with frequent thermal damage, so that the efficient working state of the ABJT2 in the second branch can be effectively ensured from the circuit structure angle, the problem of thermal damage of the ABJT2 caused by uneven triggering of slower voltage pulses is fundamentally avoided, the irreversible process of the Marx circuit caused by the thermal damage of the ABJT2 and the gradual damage of the circuit is effectively solved, and the use reliability of the ABJT 2-ABJTn in the Marx circuit is improved.

The utility model also provides a pulse power system which comprises the multistage marx circuit with primary acceleration triggering.

It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the utility model and is not intended to limit the utility model, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the utility model are intended to be included within the scope of the utility model.

Claims

1. A multi-stage marx circuit with primary acceleration triggering, comprising a primary acceleration circuit and a plurality of unipolar marx circuits, wherein the primary acceleration circuit comprises a drift step recovery diode DSRD, a DSRD trigger circuit and an avalanche transistor ABJT1;

2. The multi-stage marx circuit with primary acceleration triggering of claim 1, wherein the DSRD trigger circuit includes a power switch Q1, a high voltage direct current power supply DC1, a magnetic saturation transformer Tr, and current limiting resistors R and Rx1;

3. The multi-level marx circuit with primary acceleration triggering of claim 1, wherein the number of levels of the multi-level marx circuit is 5-30.

4. The multi-stage marx circuit with primary acceleration triggering of claim 2, wherein the power switch Q1 employs a field effect transistor.

5. A pulsed power system comprising a multilevel marx circuit with primary acceleration triggering as claimed in any one of claims 1 to 4.