High-voltage switch protection circuit of cathode power supply module

Abstract

The utility model provides a high-voltage switch protection circuit of a cathode power supply module, which is characterized in that the cathode power supply module converts 750V direct-current input voltage into-35kv high voltage, the positive end of the output end of the cathode power supply module is connected with 0V, and the negative end of the output end of the cathode power supply module is connected with a cathode of a traveling wave tube through the high-voltage switch protection circuit, so that a high-voltage power supply is provided for the cathode of the traveling wave tube; the high-voltage switch protection circuit comprises a plurality of groups of voltage-dividing assemblies which are connected in series, each group of voltage-dividing assembly comprises a plurality of switch modules which are connected in series, and the cathode power supply module works in a pulse mode through on-off of each switch module. According to the utility model, the pulse working mode of the cathode power supply module and the protection of the cathode power supply module are realized through the switching-on and switching-off of the high-voltage switch protection circuit.

Description

Technical Field

[0001] This utility model relates to the field of high-voltage power supply technology, and more specifically, to a high-voltage switch protection circuit for a cathode power supply module. Background Technology

[0002] A traveling wave tube (TWT) has multiple polarities, each requiring a different voltage. Therefore, different power supply modules are used to power the different polarities of the TWT. Specifically, the cathode of the TWT is powered by a cathode power supply module. This cathode power supply module requires control circuitry to ensure it provides a stable voltage to the cathode of the TWT in a specific operating mode. Summary of the Invention

[0003] This utility model addresses the technical problems existing in the prior art by providing a high-voltage switch protection circuit for a cathode power supply module.

[0004] This utility model provides a high-voltage switch protection circuit for a cathode power module. The cathode power module converts a 750V DC input voltage into a -35kV high voltage. The positive terminal of the output terminal of the cathode power module is connected to 0V, and the negative terminal of the output terminal is connected to the cathode of the traveling wave tube through the high-voltage switch protection circuit to improve the high-voltage power supply to the cathode of the traveling wave tube.

[0005] The high-voltage switch protection circuit includes multiple voltage divider components connected in series. Each voltage divider component includes multiple switch modules connected in series. The cathode power supply module operates in pulse mode by switching each switch module on and off.

[0006] Based on the above technical solution, the present invention can be further improved as follows.

[0007] Optionally, each of the switching modules has the same circuit structure. Each switching module includes a transformer Tr, a transistor Q10, and a MOSFET Q1. The input terminal of the transformer Tr is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr is connected to the collector of the transistor Q10 through a diode D5 and a resistor R6, and also to the base of the transistor Q10 through a resistor R5. The emitter of the transistor Q10 is connected to the negative output terminal of the transformer Tr. A resistor R4 and a capacitor C6 are connected in parallel between the base and emitter of the transistor Q10. A capacitor C7, a resistor R7, and a voltage regulator are connected in parallel between the collector and emitter of the transistor Q10. Diode D6 is used. The collector of transistor Q10 is connected to the gate of MOS switch Q1 through resistor R8. The gate of MOS switch Q1 is connected to the drain of MOS switch Q1 in sequence through diode D1, resistor R22, diode D3, diode D2 and diode D4. A capacitor C4 and resistors R3 and R20 are connected in parallel across diode D3. A capacitor C5 is connected between the gate and source of MOS switch Q1. Resistors R17, R1 and R2 are connected between the drain and source of MOS switch Q1. Capacitors C1 and C3 are connected in parallel between the drain and source of MOS switch Q1.

[0008] Optionally, the drain of each MOS switch in each group of voltage divider components is connected to the source of the previous MOS switch, and the source of each MOS switch is connected to the drain of the next MOS switch.

[0009] Optionally, the drain of the first MOS switch in each group of voltage divider components is connected to the source of the last MOS switch in the previous group of voltage divider components, and the source of the last MOS switch in each group of voltage divider components is connected to the drain of the first MOS switch in the next group of voltage divider components.

[0010] This invention provides a high-voltage switch protection circuit for a cathode power module. The high-voltage switch protection circuit is located at the output terminal of the cathode power module and includes multiple voltage-reducing components connected in series. Each voltage-reducing component includes multiple switch modules connected in series. By switching each of the switch modules on and off, the cathode power module operates in pulse mode. This invention achieves the pulse operating mode of the cathode power module and protects the cathode power module by turning the high-voltage switch protection circuit on and off. Attached Figure Description

[0011] Figure 1 A schematic diagram of a high-voltage switch protection circuit for a cathode power module provided in one embodiment of this utility model;

[0012] Figure 2 This is a schematic diagram of the high-voltage switch protection circuit according to one embodiment of the present invention;

[0013] Figure 3 This is a circuit diagram of a single-component voltage converter in one embodiment of the present invention;

[0014] Figure 4 This is a schematic diagram of a high-voltage switch protection circuit for a cathode power module, provided as another embodiment of the present invention. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. In addition, the technical features of the various embodiments or individual embodiments provided by this utility model can be arbitrarily combined to form feasible technical solutions. Such combinations are not bound by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0016] Figure 1 This is a schematic diagram of a high-voltage switch protection circuit for a cathode power module according to an embodiment of the present invention. The high-voltage switch protection circuit is mainly used to control the working mode of the cathode power module and to protect the cathode power module.

[0017] The cathode power module converts the 750V DC input voltage to a -35kV high voltage. The positive terminal of the cathode power module is connected to 0V, and the negative terminal is connected to the cathode of the traveling wave tube through a high-voltage switch protection circuit to provide a high-voltage power supply to the cathode of the traveling wave tube.

[0018] The cathode power module has two operating modes: continuous wave mode and pulse mode. The cathode power module usually operates in pulse mode. When the cathode power module operates in pulse mode, a high-voltage switch protection circuit is connected in series at the output terminal of the cathode power module. The switching is achieved by turning the high-voltage switch on and off. Considering the requirements for its operating frequency and control, the switching module with series MOSFETs is the most reliable.

[0019] The high-voltage switch protection circuit includes multiple voltage divider components connected in series. Each voltage divider component includes multiple switch modules connected in series. The cathode power supply module operates in pulse mode by switching each switch module on and off.

[0020] In this embodiment of the invention, the total output voltage of the cathode power module is 35kV. To meet the high voltage requirement, the voltage withstand capability of the MOSFETs should be as high as possible. The design involves a single MOSFET voltage divider of 1000V (a 1700V MOSFET is selected). One voltage divider assembly contains four MOSFETs, therefore a total of... That is, 9 voltage divider components, with some redundancy, 10 voltage divider components are needed. The final selected MOSFET specification is 1700V / 100A.

[0021] The high-voltage switch protection circuit consists of multiple MOSFETs connected in series. Combined with the corresponding turn-on and turn-off drive circuits and voltage equalization protection circuits, it can effectively control the on / off state of the high-voltage switch and achieve reliable operation of the high-voltage switch.

[0022] The high-voltage switch protection circuit is composed of multiple identical voltage divider components, see [link / reference]. Figure 2 This is a simplified schematic diagram of the working principle of a high-voltage switch protection circuit. The high-voltage switch protection circuit includes multiple voltage-reducing components connected in series. Each voltage-reducing component includes multiple series-connected switching transistors and their related circuit components.

[0023] It should be noted that MOSFETs, due to their excellent switching characteristics, are frequently used as solid-state switches in circuits. However, because a single MOSFET can only withstand a limited voltage, multiple MOSFETs are typically connected in series for high-voltage switching. The gate of each MOSFET is controlled by an independent drive circuit. By ensuring consistency in the turn-on and turn-off drive signals, the drive circuits, and the MOSFETs themselves, the high-voltage switch with a series MOSFET structure can effectively achieve turn-on and turn-off under high-voltage conditions. When all MOSFETs are on, the entire circuit is on; when any one MOSFET is off, the entire circuit is off. This design provides higher voltage withstand capability and better current control.

[0024] Therefore, the high-voltage switch protection circuit uses MOSFETs connected in series. Figure 2 The diagram shows a high-voltage switch protection circuit comprising 10 voltage setters. Figure 3 Each voltage converter assembly is shown to include four MOS switches.

[0025] The connection relationship of the multiple voltage divider components is as follows: the drain of the first MOS switch in each voltage divider component is connected to the source of the last MOS switch in the previous voltage divider component, and the source of the last MOS switch in each voltage divider component is connected to the drain of the first MOS switch in the next voltage divider component.

[0026] The connection relationship of the multiple MOS switches in each voltage-dividing module is as follows: the drain of each MOS switch in each voltage-dividing module is connected to the source of the previous MOS switch, and the source of each MOS switch is connected to the drain of the next MOS switch.

[0027] One of the key aspects of high-voltage switch protection circuit design is ensuring the consistency of MOSFET turn-on and turn-off. Therefore, a driving method is adopted where multiple components are coupled to the gate of the corresponding MOSFET through an isolation transformer using the same drive signal. That is, the primary windings of each switch are constructed using the same cable passing through each magnetic core. This method effectively ensures the consistency of the drive signal; the turn-off method follows the same principle.

[0028] The MOS switch is controlled by two sets of transformers. During turn-on, an external full-bridge circuit provides an alternating drive signal, which is then rectified by the turn-on transformer and connected to a rectifier diode and related circuitry to generate a corresponding high-level signal. During turn-off, the turn-on signal is stopped, and simultaneously, the turn-off signal is coupled from the turn-off transformer to the base of the transistor, discharging the capacitance between the gate (G) and source (S) terminals of the MOS switch, thus turning off the MOS switch.

[0029] See Figure 4 This is a schematic diagram of a high-voltage switch protection circuit. Each voltage conversion group includes multiple switch modules connected in series, and the circuit structure of each switch module is identical. For example, Figure 4The diagram shows that each voltage divider assembly includes four switching modules, all with identical circuit diagrams. The first switching module includes a transformer Tr1, a transistor Q10, and a MOSFET Q1. The input terminal of the transformer Tr1 is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr1 is connected to the collector of the transistor Q10 via diode D5 and resistor R6, and also to the base of the transistor Q10 via resistor R5. The emitter of the transistor Q10 is connected to the negative output terminal of the transformer Tr1. A resistor R4 and a capacitor C6 are connected in parallel between the base and emitter of the transistor Q10. A capacitor C7, a resistor R7, and a Zener diode D6 are connected in parallel between the collector and emitter of the transistor Q10. The collector of transistor Q10 is connected to the gate of MOS switch Q1 through resistor R8. The gate of MOS switch Q1 is connected to the drain of MOS switch Q1 in sequence through diode D1, resistor R22, diode D3, diode D2 and diode D4. A capacitor C4 and resistors R3 and R20 are connected in parallel across diode D3. A capacitor C5 is connected between the gate and source of MOS switch Q1. Resistors R17, R1 and R2 are connected between the drain and source of MOS switch Q1. Capacitors C1 and C3 are connected in parallel between the drain and source of MOS switch Q1.

[0030] Among them, see Figure 4 The second switching module includes a transformer Tr2, a transistor Q20, and a MOSFET Q2. The input terminal of the transformer Tr2 is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr2 is connected to the collector of the transistor Q20 through a diode D9 and a resistor R12, and to the base of the transistor Q20 through a resistor R11. The emitter of the transistor Q20 is connected to the negative output terminal of the transformer Tr2. A resistor R10 and a capacitor C11 are connected in parallel between the base and emitter of the transistor Q20. A capacitor C12, a resistor R13, and a Zener diode D10 are connected in parallel between the collector and emitter of the transistor Q20. The collector of transistor Q20 is connected to the gate of MOS switch Q2 through resistor R15. The gate of MOS switch Q2 is connected to the drain of MOS switch Q2 in sequence through diode D8, resistor R21, diode D11, diode D7, and diode D12. A capacitor C14 and resistors R14 and R19 are connected in parallel across diode D11. A capacitor C10 is connected between the gate and source of MOS switch Q2. Resistors R18, R16, and R9 are connected between the drain and source of MOS switch Q2. A capacitor C9 and capacitor C15 are connected in parallel between the drain and source of MOS switch Q2.

[0031] The third switching module includes a transformer Tr3, a transistor Q30, and a MOSFET Q3. The input terminal of the transformer Tr3 is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr3 is connected to the collector of the transistor Q30 through a diode D14 and a resistor R26, and to the base of the transistor Q30 through a resistor R25. The emitter of the transistor Q30 is connected to the negative output terminal of the transformer Tr3. A resistor R24 ​​and a capacitor C13 are connected in parallel between the base and emitter of the transistor Q30. A capacitor C16, a resistor R27, and a Zener diode D15 are connected in parallel between the collector and emitter of the transistor Q30. The collector of Q30 is connected to the gate of the MOS switch Q3 through resistor R29. The gate of the MOS switch Q3 is connected to the drain of the MOS switch Q3 in sequence through diode D23, resistor R39, diode D16, diode D13 and diode D22. A capacitor C24 and resistors R41 and R42 are connected in parallel across diode D16. A capacitor C8 is connected between the gate and source of the MOS switch Q3. Resistors R37, R29 and R23 are connected between the drain and source of the MOS switch Q3. Capacitors C2 and C17 are connected in parallel between the drain and source of the MOS switch Q3.

[0032] The fourth switching module includes a transformer Tr4, a transistor Q40, and a MOSFET Q4. The input terminal of the transformer Tr4 is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr4 is connected to the collector of the transistor Q40 through a diode D18 and a resistor R33, and to the base of the transistor Q40 through a resistor R32. The emitter of the transistor Q40 is connected to the negative output terminal of the transformer Tr4. A resistor R31 and a capacitor C20 are connected in parallel between the base and emitter of the transistor Q40. A capacitor C21, a resistor R34, and a Zener diode D19 are connected in parallel between the collector and emitter of the transistor Q40. The collector of transistor 40 is connected to the gate of transistor Q4 via resistor R35. The gate of transistor Q4 is connected to the drain of transistor Q4 via diode D24, resistor R40, diode D20, diode D17, and diode D21. A capacitor C23 and resistors R43 and R44 are connected in parallel across diode D20. A capacitor 19 is connected between the gate and source of transistor Q4. Resistors R38, R36, and R30 are connected between the drain and source of transistor Q4. Capacitors C18 and C22 are connected in parallel between the drain and source of transistor Q4.

[0033] in, Figure 4 In this diagram, J1 represents the drain and J2 represents the source. The J1 of this voltage converter is connected to the J2 of the previous voltage converter, and the J2 of this voltage converter is connected to the J1 of the next voltage converter.

[0034] This invention provides a high-voltage switch protection circuit for a cathode power module. The high-voltage switch protection circuit is located at the output terminal of the cathode power module and includes multiple voltage-reducing components connected in series. Each voltage-reducing component includes multiple switch modules connected in series. By switching each of the switch modules on and off, the cathode power module operates in pulse mode. This invention achieves the pulse operating mode of the cathode power module and protects the cathode power module by turning the high-voltage switch protection circuit on and off.

[0035] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0036] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0037] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A high-voltage switch protection circuit for a cathode power supply module, characterized in that, The cathode power supply module converts the 750V DC input voltage into a -35kV high voltage. The positive terminal of the cathode power supply module is connected to 0V, and the negative terminal of the output terminal is connected to the cathode of the traveling wave tube through a high voltage switch protection circuit to provide a high voltage power supply to the cathode of the traveling wave tube. The high-voltage switch protection circuit includes multiple voltage divider components connected in series. Each voltage divider component includes multiple switch modules connected in series. The cathode power supply module operates in pulse mode by switching each switch module on and off.

2. The high-voltage switch protection circuit according to claim 1, characterized in that, Each of the aforementioned switching modules has the same circuit structure. Each switching module includes a transformer Tr, a transistor Q10, and a MOSFET Q1. The input terminal of the transformer Tr is connected to the negative output terminal of the cathode power supply module. The positive output terminal of the transformer Tr is connected to the collector of the transistor Q10 through a diode D5 and a resistor R6, and also to the base of the transistor Q10 through a resistor R5. The emitter of the transistor Q10 is connected to the negative output terminal of the transformer Tr. A resistor R4 and a capacitor C6 are connected in parallel between the base and emitter of the transistor Q10. A capacitor C7, a resistor R7, and a Zener diode are connected in parallel between the collector and emitter of the transistor Q10. The collector of transistor Q10 is connected to the gate of MOS switch Q1 via resistor R8. The gate of MOS switch Q1 is connected to the drain of MOS switch Q1 in sequence via diode D1, resistor R22, diode D3, diode D2, and diode D4. A capacitor C4 and resistors R3 and R20 are connected in parallel across diode D3. A capacitor C5 is connected between the gate and source of MOS switch Q1. Resistors R17, R1, and R2 are connected between the drain and source of MOS switch Q1. Capacitors C1 and C3 are connected in parallel between the drain and source of MOS switch Q1.

3. The high-voltage switch protection circuit according to claim 2, characterized in that, In each group of voltage divider components, the drain of each MOS switch is connected to the source of the previous MOS switch, and the source of each MOS switch is connected to the drain of the next MOS switch.

4. The high-voltage switch protection circuit according to claim 2, characterized in that, The drain of the first MOS switch in each group of voltage divider components is connected to the source of the last MOS switch in the previous group of voltage divider components, and the source of the last MOS switch in each group of voltage divider components is connected to the drain of the first MOS switch in the next group of voltage divider components.

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