All-solid-state microsecond bidirectional high-voltage large-current pulse switch

Abstract

The invention relates to an all-solid-state microsecond bidirectional high-voltage large-current pulse switch, which adopts a magnetic coupling isolation mode to construct an efficient isolation circuit. The magnetic rings are used as isolation devices between the high-voltage circuit and the low-voltage circuit, the magnetic coupling isolation circuit is constructed by the multiple magnetic rings and the high-voltage wires, physical isolation of the high-voltage circuit and the low-voltage circuit is achieved, and the safety of the system is ensured. A driving signal is synchronously transmitted to the high-voltage main circuit through the magnetic coupling isolation circuit and serves as a trigger signal to control opening of the bidirectional silicon controlled rectifier, and reliable bidirectional conduction of the circuit is achieved by changing the polarity of the trigger signal. According to the solid-state switch, the plurality of bidirectional silicon controlled rectifiers are connected in series and in parallel, so that the voltage resistance and the through-current capability of the solid-state switch are improved, the problem of performance limitation of a single switching device is solved, and a new implementation mode is provided for working of the solid-state switch in a large-current and high-voltage environment.

Description

Technical Field

[0001] The invention relates to a bidirectional solid-state switch, in particular to a bidirectional solid-state switch capable of bearing high voltage and large current, and belongs to the technical field of power electronic devices. Background Art

[0002] Solid-state switches are an important component of modern power electronic systems. Traditional electromagnetic relays have been gradually replaced by solid-state switches due to the physical limitations of their mechanical contacts, such as wear, contact jitter, noise, etc. Solid-state switches have been widely used in many fields due to their advantages such as no contacts, no action noise, fast switching speed, no spark interference and high reliability.

[0003] At present, it is difficult for a single solid-state switch device to achieve high voltage and high current at the same time, so it is necessary to use multiple devices in series and parallel. Most commercial solid-state switches are designed with thyristors and SiC MOSFETs. The disadvantage is that the switch itself is unidirectional, and a complex circuit is required to achieve bidirectional conduction, and the cost is also very high. Therefore, designing a simple topology, low cost, high-performance, all-solid-state microsecond bidirectional high-voltage and high-current pulse switch has become an urgent problem for technicians in this field.

[0004] The "all-solid-state nanosecond high-voltage pulse switch" in the prior art can only achieve pulse discharge in a single direction and can only be used in small current situations.

[0005] The prior art discloses a "load switch capable of bidirectional conduction and current limiting". Although this technology realizes a bidirectional conduction switch, the drive circuit design is complex and is applied to low-voltage occasions such as lithium battery balancing. Summary of the invention

[0006] The purpose of the present invention is to overcome the above shortcomings and provide a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch for solving the problem of high-speed bidirectional conduction in high-voltage and high-current situations.

[0007] The object of the present invention is achieved by the following technical solutions: an all-solid-state microsecond bidirectional high-voltage and high-current pulse switch, comprising a high-low voltage isolation module, a trigger module, a voltage balancing module and a bidirectional thyristor; The high and low voltage isolation module is used to isolate the high voltage main circuit from the drive signal side and transmit the drive signal; The trigger module includes resistors R1, R2, and R3, which are used to adjust the voltage of the trigger signal entering the bidirectional thyristor control stage, thereby adjusting the current size of the control stage; The voltage balancing module includes a static voltage balancing resistor R4 and an RCD buffer circuit. The RCD buffer circuit includes a buffer resistor R5, a diode D1 and a buffer capacitor C2. The static voltage balancing resistor R4 is connected in parallel at both ends of the bidirectional thyristor M1. The diode D1 and the buffer resistor R5 are connected in parallel and then connected in series with the buffer capacitor C2. A triac is a screened three-terminal bidirectional thyristor.

[0008] A further improvement of the present invention is that the high and low voltage isolation module adopts magnetic coupling isolation technology, and its core components include magnetic rings and high-voltage insulated wires. The overall structure can be regarded as a multi-winding transformer. The multi-winding transformer includes multiple independent transformer units TX1, TX2 to TXn, and these transformer units share a primary side.

[0009] A further improvement of the present invention is that the high and low voltage isolation module overcomes the inconsistency in switch opening, and utilizes a single high voltage insulated wire in coordination with multiple magnetic rings to jointly realize an efficient electromagnetic induction process.

[0010] A further improvement of the present invention is that the high and low voltage isolation module adopts an integrated design of different numbers of magnetic rings and high voltage insulated wires according to the voltage level of the switch application.

[0011] A further improvement of the present invention is that the high and low voltage isolation modules can transmit drive signals of opposite polarities, thereby achieving bidirectional conduction of the bidirectional thyristor.

[0012] A further improvement of the present invention is that the drive signal is transmitted to the trigger control part of the bidirectional thyristor via the high and low voltage isolation module. At this time, the bidirectional thyristor is in a high voltage working environment. By using precise signal synchronization technology, the drive signal can implement unified and coordinated triggering operations on multiple bidirectional thyristors, thereby making the switch opening time reach microseconds.

[0013] A further improvement of the present invention is that by selecting a suitable resistance value, the trigger module can provide accurate voltage and current.

[0014] A further improvement of the present invention is that: when the bidirectional thyristor is turned off, the voltage across the two ends of the bidirectional thyristor is mainly determined by the static equalizing resistor. The main purpose of the equalizing resistor is to ensure that each bidirectional thyristor in the series can evenly share the voltage. The resistance value of the resistor ensures that under normal working conditions, the voltage across each bidirectional thyristor M1 is equal; the equalizing resistor can withstand the current flowing through the circuit; the rated current of the resistor is greater than or equal to the maximum current that may appear in the circuit to avoid overheating or burning of the resistor.

[0015] A further improvement of the present invention is that in the RCD snubber circuit, when an overvoltage is generated across the bidirectional thyristor M1, the diode D1 bypasses the charging current of the resistor, effectively shunting the charging current that would otherwise pass through the resistor R5, ensuring that the resistor R5 consumes energy only when the capacitor C2 is in a discharging state, thereby reducing the rate of change of the voltage across the switch during the switching transient.

[0016] Compared with the prior art, the present invention has the following advantages: 1. The high and low voltage isolation module of the present invention adopts magnetic coupling isolation. The magnetic ring is used as the isolation device between the high and low voltage circuits, and the magnetic coupling isolation circuit constructed by multiple magnetic rings and high-voltage wires realizes the physical isolation of the high and low voltage circuits and ensures the safety of the system. The driving signal is synchronously transmitted to the high voltage main circuit through the magnetic coupling isolation circuit, and is used as a trigger signal to control the opening of the bidirectional thyristor. By changing the polarity of the trigger signal, the circuit can be reliably bidirectionally conducted.

[0017] 2. To address the problems of low withstand voltage and low current in existing solid-state switches. By connecting multiple bidirectional thyristors in series and in parallel, the withstand voltage and current capacity of solid-state switches are improved. This method solves the performance limitations of a single switch device and provides a new way for solid-state switches to work in high current and high voltage environments. Compared with previous circuits, the use of bidirectional thyristors reduces the number of devices by half, reduces costs, and improves reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a structural block diagram of a fully solid-state microsecond-level bidirectional high-voltage and high-current pulse switch based on a bidirectional thyristor.

[0019] Figure 2 It is a schematic diagram of the structure of the high and low voltage isolation module and the trigger module of the present invention.

[0020] Figure 3 The present invention is a schematic diagram of a single bidirectional thyristor high and low voltage isolation and trigger voltage equalization circuit.

[0021] Figure 4 This is a circuit diagram of multiple bidirectional thyristors connected in series and parallel in the present invention.

[0022] Figure 5 Voltage waveform across M1 at the moment it is turned on.

[0023] Figure 6 Voltage waveform across M2 at the moment it is turned on.

[0024] Figure 7 Voltage waveform across M3 at the moment it is turned on.

[0025] Figure 8 Voltage waveform across M4 at the moment it is turned on.

[0026] Fig. 9 Voltage waveform across M5 at the moment it is turned on.

[0027] Fig.10 Voltage waveform across M6 at the moment it is turned on.

[0028] Fig.11 This is the open circuit voltage waveform diagram when the switch of the present invention is turned on.

[0029] Fig.12 This is a short-circuit current waveform diagram when the switch of the present invention is turned on. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The elements and features described in one embodiment of the present invention may be combined with the elements and features shown in one or more other embodiments. It should be noted that for the purpose of clarity, the representation and description of components and processes that are not related to the present invention and are known to those of ordinary skill in the art are omitted in the description. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0031] A fully solid-state microsecond bidirectional high voltage and high current pulse switch, such as Figure 1 The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch shown in the figure is composed of high-low voltage isolation module, trigger module, voltage balancing module and bidirectional thyristor. The driving signal and the primary side of the high-low voltage isolation module are low-voltage circuits, and the secondary side of the high-low voltage isolation module, the trigger module and the bidirectional thyristor are in the high-voltage circuit. Figure 2 The schematic diagram of the high and low voltage isolation module and the trigger module structure is shown in the figure. The drive signal first passes through a specially designed high and low voltage isolation module, which integrates a single high-voltage insulated wire and multiple magnetic toroidal transformers to form an efficient signal transmission link. Each magnetic toroidal transformer ensures that the drive signal can reach the trigger circuit, thereby accurately controlling the conduction state of the bidirectional thyristor. The magnetic toroidal transformer uses the air gap between the input winding and the output winding to effectively isolate the low-voltage end from the high-voltage end to prevent direct electrical contact between the two. The drive signal is transmitted to the trigger module through the high and low voltage isolation module. The high level of the controllable drive signal is 2V. After the drive signal passes through the high and low voltage isolation module, the level is increased to 10V. The trigger module converts the 10V high level transmitted from the magnetic coupling isolation module into a trigger signal with a rated voltage of 1.3V and a current greater than 80mA, and inputs it to the control stage of the bidirectional thyristor to control the opening of the bidirectional thyristor. The conduction direction of the bidirectional thyristor can be changed by changing the polarity of the drive signal. As Figure 3 The figure shows the high-voltage side single bidirectional thyristor high-low voltage isolation and triggering equalizing circuit. R1 is 10Ω, R2 is 47Ω, and R3 is 100Ω. The bidirectional thyristor is connected in parallel with the static equalizing resistor and the RCD snubber circuit to protect the switch from damage caused by voltage spikes. Each switch tube is connected in parallel with the snubber circuit and the equalizing resistor. The RCD snubber circuit consists of a resistor, a capacitor, and a diode. The resistor is 1Ω, the capacitor is 100nF, and the diode mainly prevents the reverse flow of current. When reverse voltage appears in the circuit, the diode can prevent the flow of current, thereby protecting the electronic components in the circuit. The equalizing resistor is 5MΩ, which is used to make the series switch tubes bear equal voltage and prevent excessive leakage current. Figure 4 The figure shows a series-parallel circuit of multiple bidirectional thyristors. The discharge circuit is composed of R2, R3, R4, R5, and L1. Figures 5 to 10 The figure shows a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch with six bidirectional thyristors connected in series under a voltage of 3kV, and a voltage waveform of a single bidirectional thyristor when the pulse switch is working. In the figure, a single bidirectional thyristor withstands a voltage of about 500V. At the moment of opening, the voltage spike is small, the voltage overshoot is less than 10%, and the voltage spike does not exceed the withstand voltage of the bidirectional thyristor of 800V. The switch opening time is within 1, reaching the microsecond level.

[0032] The high and low voltage isolation module (reference Figure 3 , 4 ) is used to isolate the high voltage main circuit from the drive signal side and transmit the drive signal; Furthermore, the high and low voltage isolation module adopts magnetic coupling isolation technology, and its core components include magnetic rings and high-voltage insulated wires. The overall structure can be regarded as a multi-winding transformer, which includes multiple independent transformer units such as TX1, TX2, and TXn, and these transformer units share a primary side. The key to this design is that through the combination of the magnetic ring and the surrounding air medium, effective electrical isolation between the high-voltage circuit and the low-voltage circuit is achieved, ensuring safety and stability.

[0033] Furthermore, the high and low voltage isolation module overcomes the inconsistency of switch opening. Its innovation lies in the use of a single high voltage insulated wire in coordination with multiple magnetic rings to jointly realize an efficient electromagnetic induction process. The core concept of this design is to convert the drive signal from the low voltage side into the trigger signal required by the high voltage side through a precise electromagnetic conversion mechanism, and fine-tune the devices of each trigger branch to ensure that all bidirectional thyristors can be turned on synchronously.

[0034] Furthermore, the high and low voltage isolation module adopts an integrated design of different numbers of magnetic rings and high-voltage insulated wires according to the voltage level of the switch application, aiming to meet the specific trigger voltage requirements of the bidirectional thyristor. In view of the relatively small trigger voltage of such devices, the ratio of the primary winding to the winding on each magnetic ring on the secondary side is selected according to the actual use situation, such as being set to 1:5, so as to optimize the conversion efficiency and strength of the signal, ensuring that the signal is not distorted and can effectively trigger the target component when crossing the high and low voltage boundaries.

[0035] Furthermore, the high and low voltage isolation module can transmit drive signals of opposite polarities, thereby achieving bidirectional conduction of the bidirectional thyristor.

[0036] The trigger module (refer to Figure 3 ) includes resistors R1, R2, and R3, which are used to adjust the voltage of the trigger signal entering the bidirectional thyristor control stage, thereby adjusting the current size of the control stage; Furthermore, the drive signal is transmitted to the trigger control part of the bidirectional thyristor via the high and low voltage isolation module. At this time, the bidirectional thyristor is in a high voltage working environment. By using precise signal synchronization technology, the drive signal can implement a unified and coordinated trigger operation on multiple bidirectional thyristors, so that the switch opening time reaches the microsecond level.

[0037] Furthermore, by selecting the appropriate resistance value, the trigger module can provide accurate voltage and current, which is essential for the trigger level and trigger power that need to be precisely controlled. The resistor network has a simple structure, is easy to implement and debug, and has low cost, which improves the overall reliability and economy of the trigger module.

[0038] The pressure equalization module (reference Figure 3 ) includes a static voltage-equalizing resistor R4 and an RCD snubber circuit. The RCD snubber circuit includes a snubber resistor R5, a diode D1 and a snubber capacitor C2. The static voltage-equalizing resistor R4 is connected in parallel at both ends of the bidirectional thyristor M1. The diode D1 and the snubber resistor R5 are connected in parallel and then connected in series with the snubber capacitor C2.

[0039] Furthermore, the voltage across the bidirectional thyristor when turned off is mainly determined by the static grading resistor. The main purpose of the grading resistor is to ensure that each bidirectional thyristor in the series connection can share the voltage evenly. The resistance value of the resistor should ensure that under normal operating conditions, the voltage across each bidirectional thyristor M1 is approximately equal. The grading resistor needs to be able to withstand the current flowing through the circuit. The rated current of the resistor should be greater than or equal to the maximum current that may appear in the circuit to avoid overheating or burning of the resistor.

[0040] Furthermore, in the RCD snubber circuit, when an overvoltage is generated across the bidirectional thyristor M1, the diode D1 bypasses the charging current of the resistor, effectively shunting the charging current that would otherwise pass through the resistor R5, ensuring that the resistor R5 consumes energy only when the capacitor C2 is in a discharge state, thereby reducing the rate of change of the voltage across the switch during the switching transient.

[0041] The bidirectional thyristor is a screened three-terminal bidirectional thyristor.

[0042] The present invention realizes a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch by connecting bidirectional thyristors in series and in parallel. Compared with previous circuits, the use of bidirectional thyristors reduces the number of devices by half, reduces costs, and improves reliability. Reliable bidirectional conduction of the circuit is achieved by changing the polarity of the trigger signal. The circuit in the present invention is made of bidirectional thyristors in series and in parallel, and can be applied to new energy, industrial automation and other fields to improve equipment efficiency and stability. The circuit includes a high and low voltage isolation module, a trigger module, a voltage equalization module and a bidirectional thyristor. By integrating these functional modules, the circuit realizes microsecond conduction of the switch, reduces switching losses, optimizes switch performance, and provides a new solution for the development of pulse switches. The present invention can achieve bidirectional pulse discharge at high voltage and high current, and can be applied to special scenarios.

[0043] The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch of the present invention has fast response and bidirectional control capabilities, so it can better cope with fluctuations and changes in the power system and ensure the stable operation of the power system.

[0044] The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch of the present invention reduces equipment maintenance and replacement costs. Since the solid-state switch has lower energy consumption and heat generation and has no mechanical parts, the maintenance and replacement costs of the equipment can be reduced. At the same time, the solid-state switch has a long service life and can reduce the cost of frequent equipment replacement.

[0045] The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch of the present invention can improve the safety and reliability of equipment. The rapid response and precise control of the solid-state switch can reduce the generation of dangerous phenomena such as arcs and sparks, thereby improving the safety and reliability of equipment.

[0046] Finally, it should be noted that: although the present invention and its advantages have been described in detail above, it should be understood that various changes, substitutions and transformations can be made without exceeding the spirit and scope of the present invention as defined by the attached claims. Moreover, the scope of the present invention is not limited to the specific embodiments of the processes, devices, means, methods and steps described in the specification. It will be easily understood by those of ordinary skill in the art from the disclosure of the present invention that existing and future processes, devices, means, methods or steps that perform substantially the same functions as the corresponding embodiments described herein or obtain substantially the same results as the corresponding embodiments described herein can be used according to the present invention. Therefore, the attached claims are intended to include such processes, devices, means, methods or steps within their scope.

Claims

1. A fully solid-state microsecond bidirectional high-voltage and high-current pulse switch, characterized in that: Including high and low voltage isolation module, trigger module, voltage equalization module and bidirectional thyristor; The high and low voltage isolation module is used to isolate the high voltage main circuit from the drive signal side and transmit the drive signal; The trigger module includes resistors R1, R2, and R3, which are used to adjust the voltage of the trigger signal entering the bidirectional thyristor control stage, thereby adjusting the current size of the control stage; The voltage balancing module includes a static voltage balancing resistor R4 and an RCD buffer circuit, the RCD buffer circuit includes a buffer resistor R5, a diode D1 and a buffer capacitor C2, the static voltage balancing resistor R4 is connected in parallel at both ends of the bidirectional thyristor M1, the diode D1 and the buffer resistor R5 are connected in parallel, and then connected in series with the buffer capacitor C2; The bidirectional thyristor is a screened three-terminal bidirectional thyristor.

2. According to claim 1, a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch is characterized in that: The high and low voltage isolation module adopts magnetic coupling isolation technology, and its core components include magnetic rings and high-voltage insulated wires. The overall structure can be regarded as a multi-winding transformer. The multi-winding transformer includes multiple independent transformer units TX1, TX2 to TXn, and these transformer units share a primary side.

3. According to claim 1, a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch is characterized in that: The high and low voltage isolation module overcomes the inconsistency in switch opening, and utilizes a single high voltage insulated wire in coordination with multiple magnetic rings to jointly realize an efficient electromagnetic induction process.

4. According to claim 1, a fully solid-state microsecond bidirectional high-voltage and high-current pulse switch is characterized in that: The high and low voltage isolation module adopts an integrated design of different numbers of magnetic rings and high voltage insulated wires according to the voltage level of the switch application.

5. According to claim 1, the all-solid-state microsecond bidirectional high-voltage and high-current pulse switch is characterized in that: The high and low voltage isolation module can transmit driving signals of opposite polarities, thereby achieving bidirectional conduction of the bidirectional thyristor.

6. The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch according to claim 1, characterized in that: The driving signal is transmitted to the trigger control part of the bidirectional thyristor through the high and low voltage isolation module. At this time, the bidirectional thyristor is in a high voltage working environment. By using precise signal synchronization technology, the driving signal can implement unified and coordinated triggering operations on multiple bidirectional thyristors, so that the switch opening time reaches the microsecond level.

7. The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch according to claim 1, characterized in that: By choosing the appropriate resistor values, the trigger module can provide precise voltage and current.

8. The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch according to claim 1, characterized in that: When the bidirectional thyristor is turned off, the voltage across the two ends of the bidirectional thyristor is mainly determined by the static grading resistor. The main purpose of the grading resistor is to ensure that each bidirectional thyristor in the series can evenly share the voltage. The resistance value of the resistor ensures that under normal working conditions, the voltage across each bidirectional thyristor M1 is equal; the grading resistor can withstand the current flowing through the circuit; the rated current of the resistor is greater than or equal to the maximum current that may appear in the circuit to avoid overheating or burning of the resistor.

9. The all-solid-state microsecond bidirectional high-voltage and high-current pulse switch according to claim 1, characterized in that: RCD snubber circuit, when overvoltage occurs across the bidirectional thyristor M1, the diode D1 bypasses the charging current of the resistor, effectively shunting the charging current that would otherwise pass through the resistor R5, ensuring that the resistor R5 consumes energy only when the capacitor C2 is in a discharged state, reducing the rate of change of the voltage across the switch during the switching transient.

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