A traveling wave tube power supply protection circuit

Abstract

An embodiment of the present invention discloses a traveling wave tube power supply protection circuit, which includes: a full-bridge inverter circuit, a transformer, a voltage doubler rectifier circuit, a sampling circuit, a control protection circuit and a drive circuit; wherein the full-bridge inverter circuit receives a power supply voltage, and is used to invert the power supply voltage and send it to the transformer; the transformer is used to amplify the inverted power supply voltage and send it to the voltage doubler rectifier circuit; the voltage doubler rectifier circuit is used to convert the received voltage into the voltage required by the traveling wave tube; the sampling circuit is connected to the voltage doubler rectifier circuit, and is used to sample the voltage or current in the power supply protection circuit and send a corresponding signal to the control protection circuit; the control protection circuit is used to determine whether the power supply is abnormal according to the received signal, and control the opening and closing of the full-bridge inverter circuit through the drive circuit.

Description

Technical Field

[0001] The invention relates to the technical field of special power supplies, and in particular to a traveling wave tube power supply protection circuit. Background Art

[0002] The microwave power module is mainly composed of a miniaturized traveling wave tube, a solid-state amplifier and a high-voltage power supply. It is an important direction for the development of vacuum electronic devices towards miniaturization and integration. It has a wide range of applications in the fields of electronic decoys, electronic jamming drones, satellite communications, ground communications, etc. As the core component of the microwave power module, the reliability of the traveling wave tube high-voltage power supply determines the service life of the module. Due to its high operating voltage, the difficulty of maintaining an ideal state of its internal vacuum, and the accumulation of charge during long-term operation, the traveling wave tube is prone to discharge under a high-voltage electric field, that is, high-voltage sparking. Therefore, the design of the spark protection circuit must be considered at the beginning of the design of the traveling wave tube high-voltage power supply. At the same time, the spiral overcurrent protection and cathode voltage overvoltage protection circuits must also be designed to ensure that the traveling wave tube high-voltage power supply is cut off in time under abnormal conditions to protect the traveling wave tube and the power supply, and restart the power supply after the abnormal state is eliminated.

[0003] The traditional solution for high-voltage spark protection of traveling wave tube power supply is to connect a large resistor in series between the output end of the high-voltage power supply and the load to limit the current. This has strict requirements on the power that the resistor can bear. The resistor is generally large in size and will cause a certain voltage drop. The series inductor absorbs the large current generated at the moment of sparking. This solution has a small resistance and the advantage is that the voltage drop can be almost ignored. However, due to the characteristic that the inductor current cannot change suddenly, it is not suitable for use under pulse working conditions. At the same time, high-voltage sparking can easily cause the voltage at the sampling point of the spiral current to increase. Depending on the cathode voltage value, it ranges from several thousand volts to more than ten thousand volts, which can easily cause damage to the control circuit. Therefore, this part of the protection circuit also needs to be further optimized. Summary of the invention

[0004] The purpose of the present invention is to provide a traveling wave tube power supply protection circuit to reduce the damage to the high-voltage power supply and the traveling wave tube caused by sparking of the traveling wave tube high-voltage power supply, excessive current in the spiral line, and overvoltage of the cathode voltage, thereby protecting the traveling wave tube high-voltage power supply and the traveling wave tube.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a traveling wave tube power supply protection circuit, the power supply protection circuit comprising:

[0007] Full-bridge inverter circuit, transformer, voltage doubler rectifier circuit, sampling circuit, control protection circuit and drive circuit;

[0008] in,

[0009] The full-bridge inverter circuit receives a power supply voltage and is used to invert the power supply voltage and then send it to the transformer;

[0010] The transformer is used to amplify the inverted power supply voltage and send it to the voltage doubling rectifier circuit;

[0011] The voltage doubler rectifier circuit is used to convert the received voltage into the voltage required by the traveling wave tube;

[0012] The sampling circuit is connected to the voltage doubler rectifier circuit and is used to sample the voltage or current in the power protection circuit and then send a corresponding signal to the control protection circuit;

[0013] The control protection circuit is used to determine whether the power supply is abnormal according to the received signal, and control the opening and closing of the full-bridge inverter circuit through the drive circuit.

[0014] In a specific embodiment, the power protection circuit further includes: a resonant circuit;

[0015] The resonant circuit is used to receive the power supply voltage after the inversion of the full-bridge inverter circuit and to perform noise removal on the power supply voltage after the inversion of the full-bridge inverter circuit and then send it to the transformer.

[0016] In a specific embodiment, the full-bridge inverter circuit includes four switching tubes for inverting a DC voltage into a high-frequency AC square wave with a frequency of 100 kHz.

[0017] In a specific embodiment, the voltage doubler rectifier circuit includes: first to tenth diodes, first to tenth capacitors of the voltage doubler rectifier circuit, an inductor, and first to third resistors of the voltage doubler rectifier circuit;

[0018] in,

[0019] The cathode of the first diode is connected to the first end of the first capacitor of the voltage doubler rectifier circuit;

[0020] The anode of the first diode is connected to the first end of the second capacitor of the voltage doubler rectifier circuit and the cathode of the second diode respectively;

[0021] The anode of the second diode is respectively connected to the second end of the first capacitor of the voltage doubler rectifier circuit, the cathode of the third diode and the first end of the third capacitor of the voltage doubler rectifier circuit;

[0022] The anode of the third diode is respectively connected to the second end of the second capacitor of the voltage doubler rectifier circuit, the cathode of the fourth diode and the first end of the fourth capacitor of the voltage doubler rectifier circuit;

[0023] The anode of the fourth diode is respectively connected to the second end of the third capacitor of the voltage doubler rectifier circuit, the cathode of the fifth diode, the first end of the fifth capacitor of the voltage doubler rectifier circuit and the first end of the first resistor of the voltage doubler rectifier circuit;

[0024] The second end of the first resistor of the voltage doubler rectifier circuit serves as the first output end of the voltage doubler rectifier circuit;

[0025] The anode of the fifth diode is respectively connected to the second end of the fourth capacitor of the voltage doubler rectifier circuit, the cathode of the sixth diode and the first end of the sixth capacitor of the voltage doubler rectifier circuit;

[0026] The anode of the sixth diode is respectively connected to the second end of the fifth capacitor of the voltage doubler rectifier circuit, the first end of the inductor, the first end of the second resistor of the voltage doubler rectifier circuit, the cathode of the seventh diode and the first end of the eighth capacitor of the voltage doubler rectifier circuit;

[0027] The second end of the second resistor of the voltage doubler rectifier circuit serves as the second output end of the voltage doubler rectifier circuit;

[0028] The second end of the inductor is respectively connected to the second end of the sixth capacitor of the voltage doubler rectifier circuit and the first end of the seventh capacitor of the voltage doubler rectifier circuit;

[0029] The anode of the seventh diode is respectively connected to the second end of the seventh capacitor of the voltage doubler rectifier circuit, the cathode of the eighth diode and the first end of the ninth capacitor of the voltage doubler rectifier circuit;

[0030] The anode of the eighth diode is respectively connected to the second end of the eighth capacitor of the voltage doubler rectifier circuit, the first end of the third resistor of the voltage doubler rectifier circuit, the cathode of the ninth diode and the first end of the tenth capacitor of the voltage doubler rectifier circuit;

[0031] The second end of the third resistor of the voltage doubler rectifier circuit serves as the third output end of the voltage doubler rectifier circuit;

[0032] The anode of the ninth diode is connected to the second end of the ninth capacitor of the voltage doubler rectifier circuit and the cathode of the tenth diode respectively;

[0033] The anode of the tenth diode is respectively connected to the second end of the tenth capacitor of the voltage doubler rectifier circuit and the first end of the protection resistor and serves as the fourth output end of the voltage doubler rectifier circuit.

[0034] In a specific embodiment, the sampling circuit includes: a spiral current sampling circuit;

[0035] The spiral current sampling circuit comprises: a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a unidirectional transient suppressor and a voltage stabilizing diode;

[0036] in,

[0037] The first end of the first resistor is connected to the cathode of the first diode, and the second end of the first resistor is respectively connected to the first end of the second resistor, the first end of the first capacitor, the first end of the third resistor and the cathode of the unidirectional transient suppressor;

[0038] The anode of the unidirectional transient suppressor is respectively connected to the second end of the second resistor, the second end of the first capacitor, the anode of the voltage stabilizing diode and the first end of the second capacitor and is grounded;

[0039] The second end of the third resistor is respectively connected to the cathode of the voltage stabilizing diode and the second end of the second capacitor and sends a spiral current sampling signal to the control protection circuit.

[0040] In a specific embodiment, the sampling circuit further includes: a cathode voltage sampling circuit;

[0041] The cathode voltage sampling circuit comprises: fourth to tenth resistors, a third capacitor and a fourth capacitor;

[0042] in,

[0043] The first end of the third capacitor is connected to the anode of the tenth diode and the first end of the fourth resistor respectively;

[0044] The second end of the fourth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the sixth resistor, the second end of the sixth resistor is connected to the first end of the seventh resistor, the second end of the seventh resistor is connected to the first end of the eighth resistor, and the second end of the eighth resistor is connected to the first end of the ninth resistor;

[0045] The second end of the ninth resistor is respectively connected to the second end of the third capacitor, the first end of the tenth resistor and the first end of the fourth capacitor and sends a cathode voltage sampling signal to the control protection circuit;

[0046] A second end of the fourth capacitor is connected to the second end of the tenth resistor and is grounded.

[0047] In a specific embodiment, the sampling circuit further includes: an ignition current sampling circuit;

[0048] The ignition current sampling circuit includes: a fifth capacitor, a sixth capacitor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a mutual inductor and an ignition current sampling circuit diode;

[0049] The first end of the fifth capacitor is connected to the anode of the tenth diode, and the second end of the fifth capacitor is connected to the first end of the mutual inductor;

[0050] The second end of the mutual inductor is grounded, the third end of the mutual inductor is connected to the first end of the eleventh resistor, and the fourth end of the mutual inductor is respectively connected to the first end of the twelfth resistor, the first end of the sixth capacitor, and the first end of the thirteenth resistor;

[0051] The second end of the eleventh resistor is respectively connected to the second end of the twelfth resistor and the anode of the ignition current sampling circuit diode;

[0052] The cathode of the ignition current sampling circuit diode is respectively connected to the second end of the sixth capacitor and the second end of the thirteenth resistor and sends an ignition current sampling signal to the control protection circuit.

[0053] In a specific embodiment, the first resistor can be a 10Ω / 5W wire wound resistor or a resistance wire.

[0054] In a specific embodiment, the turns ratio of the transformer is 1:100.

[0055] In a specific embodiment, the control and protection circuit includes a full-bridge control chip and a digital processing chip.

[0056] The beneficial effects of the present invention are as follows:

[0057] The traveling wave tube power supply protection circuit provided by the present invention reduces the failure rate and damage rate of the high-voltage power supply, improves the reliability of the traveling wave tube high-voltage power supply, realizes the organic unity of high reliability and miniaturization of the traveling wave tube high-voltage power supply, and also has the characteristics of fast response speed, low cost, small size, etc. by designing and optimizing the spiral current sampling circuit, the cathode voltage sampling circuit and the ignition current sampling circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the specific implementation methods of the present application or the existing technical solutions, the drawings required for use in the specific implementation methods or the existing technical descriptions will be briefly introduced below. Obviously, the drawings described below are an implementation method of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0059] Figure 1A schematic diagram of the structure of a traveling wave tube power supply protection circuit according to an embodiment of the present invention is shown.

[0060] Figure 2 A circuit diagram of a sampling circuit and a voltage doubling rectifier circuit in a traveling wave tube power supply protection circuit according to an embodiment of the present invention is shown.

[0061] Figure 3 A circuit diagram of a spiral current sampling circuit in a sampling circuit according to an embodiment of the present invention is shown.

[0062] Figure 4 A circuit diagram of a cathode voltage sampling circuit in a sampling circuit according to an embodiment of the present invention is shown.

[0063] Figure 5 A circuit diagram of an ignition current sampling circuit in a sampling circuit according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0064] In order to make the technical solution of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. The present invention is described in detail below through specific embodiments, but these do not constitute a limitation of the present invention. Without departing from the principle of the present invention, those skilled in the art may make variations and improvements, which should also be regarded as the protection scope of the present invention.

[0065] This embodiment provides a traveling wave tube power supply protection circuit, such as Figure 1 As shown, the power protection circuit includes: a full-bridge inverter circuit, a resonant circuit, a transformer, a voltage doubler rectifier circuit, a sampling circuit, a control protection circuit and a drive circuit.

[0066] Among them, the full-bridge inverter circuit, resonant circuit, transformer and voltage doubler rectifier circuit are connected in sequence with wires to achieve the output of multiple DC high voltages, the output end of the voltage doubler rectifier circuit is connected to the traveling wave tube load, the sampling circuit is connected to the voltage doubler rectifier circuit, the output end of the sampling circuit is connected to the input end of the control protection circuit, the output end of the control protection circuit is connected to the input end of the drive circuit, and the output end of the drive circuit is connected to the control end of the full-bridge inverter circuit.

[0067] The full-bridge inverter circuit receives a power supply voltage, and is used to invert the power supply voltage and send it to the resonant circuit; wherein the full-bridge inverter circuit includes four switching tubes, which are used to invert the power supply voltage, i.e., the DC voltage output by the traveling wave tube high-voltage power supply, into a high-frequency AC square wave with a frequency of about 100kHz, preferably, into a high-frequency AC square wave with a frequency of 100kHz.

[0068] The resonant circuit is used to receive the power supply voltage after the inversion of the full-bridge inverter circuit and send the power supply voltage after the inversion of the full-bridge inverter circuit to the transformer after de-noising. It can be understood by those skilled in the art that the resonant circuit only plays a role of de-noising. Therefore, in the absence of the resonant circuit, the full-bridge inverter circuit directly sends the power supply voltage to the transformer after inversion, which can also achieve the purpose of the present invention.

[0069] The transformer is used to amplify the inverted power supply voltage and send it to the voltage doubling rectifier circuit; wherein the primary-secondary isolation voltage of the transformer is above 10kV, which can not only amplify the high-frequency AC square wave generated by the full-bridge inverter circuit, but also isolate the input DC voltage and the output DC high voltage.

[0070] The voltage doubling rectifier circuit is used to convert the received voltage into the voltage required by the traveling wave tube, that is, to convert the high-voltage and high-frequency AC square wave output by the secondary of the transformer into the multi-channel DC high voltage required by the traveling wave tube.

[0071] The sampling circuit is used to sample the voltage or current in the power protection circuit and send a corresponding signal to the control protection circuit; wherein the sampling circuit further includes: a spiral current sampling circuit, a cathode voltage sampling circuit and an ignition current sampling circuit, to achieve sampling of the spiral current, cathode voltage and high-voltage ignition current, and send a corresponding signal to the control protection circuit.

[0072] The control protection circuit is used to determine whether the power supply is abnormal according to the received signal, and control the opening and closing of the full-bridge inverter circuit through the drive circuit; wherein, the control protection circuit includes a full-bridge control chip and a digital processing chip, the full-bridge control chip is used to generate a PWM signal, drive the switch tube in the full-bridge inverter circuit through the drive circuit to control the opening and closing of the full-bridge inverter circuit, and the digital processing chip is used to determine whether the power supply is abnormal according to the received signal, for example, high-voltage power supply sparking, excessive spiral line current or cathode voltage overvoltage are all power supply abnormalities.

[0073] like Figure 2 As shown, the voltage doubler rectifier circuit includes: first to tenth diodes D1-D10, first to tenth capacitors C*1-C*10 of the voltage doubler rectifier circuit, inductor S1 and first to third resistors Rc1-Rc3 of the voltage doubler rectifier circuit; in a specific embodiment, the capacitance values ​​of the first to tenth capacitors C*1-C*10 of the voltage doubler rectifier circuit are all 0.1uF; the resistance values ​​of the first to third resistors Rc1, Rc2 and Rc3 of the voltage doubler rectifier circuit are all 10Ω.

[0074] Among them, the cathode of the first diode D1 is connected to the first end of the first capacitor C*1 of the voltage doubler rectifier circuit; the anode of the first diode D1 is respectively connected to the first end of the second capacitor C*2 of the voltage doubler rectifier circuit and the cathode of the second diode D2; the anode of the second diode D2 is respectively connected to the second end of the first capacitor C*1 of the voltage doubler rectifier circuit, the cathode of the third diode D3 and the first end of the third capacitor C*3 of the voltage doubler rectifier circuit; the anode of the third diode D3 is respectively connected to the second end of the second capacitor C*2 of the voltage doubler rectifier circuit, the cathode of the fourth diode D4 and the first end of the fourth capacitor C*4 of the voltage doubler rectifier circuit; the anode of the fourth diode D4 is respectively connected to the first end of the second capacitor C*2 of the voltage doubler rectifier circuit, the cathode of the fourth diode D4 and the first end of the fourth capacitor C*4 of the voltage doubler rectifier circuit; the anode of the fourth diode D4 is respectively connected to the second end of the second capacitor C*2 of the voltage doubler rectifier circuit, the cathode of the fourth diode D4 and the first end of the fourth capacitor C*4 of the voltage doubler rectifier circuit; the anode of the fourth diode D4 is respectively connected to the first end of the second capacitor C*2 of the voltage doubler rectifier circuit, and the cathode of the third diode D3 is respectively connected to the first end of the second capacitor C*2 of the voltage doubler rectifier circuit, and the cathode of the fourth diode D4 is respectively connected to the first end of the second capacitor C*4 of the voltage doubler rectifier circuit. The anode of the fifth diode D5 is respectively connected to the second end of the third capacitor C*3 of the voltage doubling rectifier circuit, the cathode of the fifth diode D5, the first end of the fifth capacitor C*5 of the voltage doubling rectifier circuit and the first end of the first resistor Rc1 of the voltage doubling rectifier circuit; the second end of the first resistor Rc1 of the voltage doubling rectifier circuit serves as the first output end of the voltage doubling rectifier circuit; the anode of the fifth diode D5 is respectively connected to the second end of the fourth capacitor C*4 of the voltage doubling rectifier circuit, the cathode of the sixth diode D6 and the first end of the sixth capacitor C*6 of the voltage doubling rectifier circuit; the anode of the sixth diode D6 is respectively connected to the second end of the fifth capacitor C*5 of the voltage doubling rectifier circuit, the first end of the inductor S1, the first end of the voltage doubling rectifier circuit The first end of the second resistor Rc2 of the voltage doubler rectifier circuit, the cathode of the seventh diode D7 and the first end of the eighth capacitor C*8 of the voltage doubler rectifier circuit; the second end of the second resistor Rc2 of the voltage doubler rectifier circuit serves as the second output end of the voltage doubler rectifier circuit; the second end of the inductor S1 is respectively connected to the second end of the sixth capacitor C*6 of the voltage doubler rectifier circuit and the first end of the seventh capacitor C*7 of the voltage doubler rectifier circuit; the anode of the seventh diode D7 is respectively connected to the second end of the seventh capacitor C*7 of the voltage doubler rectifier circuit, the cathode of the eighth diode D8 and the first end of the ninth capacitor C*9 of the voltage doubler rectifier circuit; the anode of the eighth diode D8 is respectively connected to the second end of the seventh capacitor C*7 of the voltage doubler rectifier circuit, the cathode of the eighth diode D8 and the first end of the ninth capacitor C*9 of the voltage doubler rectifier circuit The second end of the eighth capacitor C*8, the first end of the third resistor Rc3 of the voltage doubler rectifier circuit, the cathode of the ninth diode D9 and the first end of the tenth capacitor C*10 of the voltage doubler rectifier circuit; the second end of the third resistor Rc3 of the voltage doubler rectifier circuit serves as the third output end of the voltage doubler rectifier circuit; the anode of the ninth diode D9 is respectively connected to the second end of the ninth capacitor C*9 of the voltage doubler rectifier circuit and the cathode of the tenth diode D10; the anode of the tenth diode D10 is respectively connected to the second end of the tenth capacitor C*10 of the voltage doubler rectifier circuit and the first end of the protection resistor Rk and serves as the fourth output end of the voltage doubler rectifier circuit; the second end of the protection resistor Rk outputs voltage.

[0075] Among them, the protection resistor Rk is a protection resistor for the cathode voltage of the traveling wave tube high voltage power supply, and the first to third resistors Rc1, Rc2 and Rc3 of the voltage doubler rectifier circuit are protection resistors for the collector voltage of the traveling wave tube high voltage power supply. In a specific embodiment, the resistance value of the protection resistor Rk is 10Ω. In addition, those skilled in the art can understand that the voltage doubler rectifier circuit is only an example, and when other voltage doubler rectifier circuits are replaced, the purpose of the present invention can also be achieved.

[0076] like Figure 2 and Figure 3 As shown, the spiral current sampling circuit in the sampling circuit includes: a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a second capacitor C2, a unidirectional transient suppressor DZ1 and a Zener diode DZ2; in a specific embodiment, the resistance value of the first resistor R1 is 10Ω, the resistance value of the third resistor R3 is 2kΩ, the voltage of the unidirectional transient suppressor DZ1 is 20V, the voltage of the Zener diode DZ2 is 5.1V, the capacitance value of the first capacitor C1 is 0.1uF, the voltage value is 1000V, and the capacitance value of the second capacitor C2 is 0.1uF.

[0077] Among them, the first end of the first resistor R1 is connected to the cathode of the first diode D1, and the second end of the first resistor R1 is respectively connected to the first end of the second resistor R2, the first end of the first capacitor C1, the first end of the third resistor R3 and the cathode of the unidirectional transient suppressor DZ1; the anode of the unidirectional transient suppressor DZ1 is respectively connected to the second end of the second resistor R2, the second end of the first capacitor C1, the anode of the zener diode DZ2 and the first end of the second capacitor C2 and is grounded GND; the second end of the third resistor R3 is respectively connected to the cathode of the zener diode DZ2 and the second end of the second capacitor C2 and sends a spiral current sampling signal to the control protection circuit.

[0078] The spiral current sampling circuit adds a 10Ω / 5W winding resistor R1 on the basis of the original sampling resistor and adopts a two-stage protection of a unidirectional transient suppressor DZ1 and a voltage regulator diode DZ2 to prevent excessive voltage and current from entering the control protection circuit during high-voltage ignition and causing damage to the low-voltage end. The winding resistor R1 is selected after repeated experiments and screening among various types of resistors. In further miniaturization, a suitable resistance wire can be selected instead.

[0079] like Figure 2 and Figure 4As shown, the voltage signal obtained by the cathode voltage sampling circuit in the sampling circuit is divided into two paths, one for realizing cathode voltage stabilization, and the other for realizing overvoltage protection by comparing with the reference voltage. The cathode voltage sampling circuit includes: fourth to tenth resistors R4-R10, a third capacitor C3 and a fourth capacitor C4; in a specific embodiment, the capacitance value of the fourth capacitor C4 is 0.01uF, and the resistance value of the tenth resistor R10 is 15kΩ.

[0080] Among them, the first end of the third capacitor C3 is respectively connected to the anode of the tenth diode D10 and the first end of the fourth resistor R4; the second end of the fourth resistor R4 is connected to the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, the second end of the seventh resistor R7 is connected to the first end of the eighth resistor R8, and the second end of the eighth resistor R8 is connected to the first end of the ninth resistor R9; the second end of the ninth resistor R9 is respectively connected to the second end of the third capacitor C3, the first end of the tenth resistor R10 and the first end of the fourth capacitor C4 and sends a cathode voltage sampling signal to the control protection circuit; the second end of the fourth capacitor C4 is connected to the second end of the tenth resistor R10 and is grounded GND.

[0081] like Figure 2 and Figure 5 As shown, the ignition current sampling circuit in the sampling circuit includes: a fifth capacitor C5, a sixth capacitor C6, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a mutual inductor T1 and an ignition current sampling circuit diode D11; in a specific embodiment, the resistance value of the eleventh resistor R11 is 10Ω, the resistance value of the twelfth resistor R12 is 10Ω, the resistance value of the thirteenth resistor R13 is 1MΩ, and the turns ratio of the mutual inductor T1 is 1:100.

[0082] The first end of the fifth capacitor C5 is connected to the anode of the tenth diode D10, and the second end of the fifth capacitor C5 is connected to the first end of the mutual inductor T1; the second end of the mutual inductor T1 is grounded GND, the third end of the mutual inductor T1 is connected to the first end of the eleventh resistor R11, and the fourth end of the mutual inductor T1 is respectively connected to the first end of the twelfth resistor R12, the first end of the sixth capacitor C6 and the first end of the thirteenth resistor R13; the second end of the eleventh resistor R11 is respectively connected to the second end of the twelfth resistor R12 and the anode of the ignition current sampling circuit diode D11; the cathode of the ignition current sampling circuit diode D11 is respectively connected to the second end of the sixth capacitor C6 and the second end of the thirteenth resistor R13 and sends an ignition current sampling signal to the control protection circuit.

[0083] The fifth capacitor C5 is a high-voltage capacitor, which plays a role in isolating high voltage. The ignition current sampling circuit uses a transformer T1 with a turn ratio of 1:100 to sample the current, and performs certain shaping on the sampled current to generate an ignition current sampling signal, which is sent to the control protection circuit for comparison and judgment. If ignition occurs, the control protection circuit cuts off the power supply and records the number of ignitions.

[0084] The traveling wave tube power supply protection circuit provided in the present embodiment improves the anti-sparking capability of the high-voltage power supply by using a 10Ω / 5W wound resistor or a resistance wire instead of a thick film resistor or a metal film resistor as an ignition current absorption resistor; by adding a two-stage protection measure of a unidirectional transient suppressor and a voltage regulator diode in the spiral current protection circuit, the control protection circuit can be protected when a high-voltage ignition occurs; by using a mutual inductor in the ignition current sampling circuit to sample the ignition current from the low end of the filter capacitor, i.e., the fifth capacitor C5, it is more reliable than traditional resistance sampling and also realizes fast sampling within 3us, solving the problems of sampling safety and speed; the traveling wave tube power supply protection circuit provided in the present embodiment reduces the failure rate and damage rate of the high-voltage power supply, improves the reliability of the traveling wave tube high-voltage power supply, realizes the organic unity of high reliability and miniaturization of the traveling wave tube high-voltage power supply, and also has the characteristics of fast response speed, low cost, small size, etc. through the design and optimization of the spiral current sampling circuit, the cathode voltage sampling circuit and the ignition current sampling circuit.

[0085] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A traveling wave tube power supply protection circuit, characterized in that: The power protection circuit comprises: Full-bridge inverter circuit, transformer, voltage doubler rectifier circuit, sampling circuit, control protection circuit and drive circuit; in, The full-bridge inverter circuit receives a power supply voltage and is used to invert the power supply voltage and then send it to the transformer; The transformer is used to amplify the inverted power supply voltage and send it to the voltage doubling rectifier circuit; The voltage doubler rectifier circuit is used to convert the received voltage into the voltage required by the traveling wave tube; The sampling circuit is connected to the voltage doubler rectifier circuit and is used to sample the voltage or current in the power protection circuit and then send a corresponding signal to the control protection circuit; The sampling circuit comprises: a spiral current sampling circuit; The spiral current sampling circuit comprises: a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a unidirectional transient suppressor and a voltage stabilizing diode; in, The first end of the first resistor is connected to the cathode of the first diode, and the second end of the first resistor is respectively connected to the first end of the second resistor, the first end of the first capacitor, the first end of the third resistor and the cathode of the unidirectional transient suppressor; The anode of the unidirectional transient suppressor is respectively connected to the second end of the second resistor, the second end of the first capacitor, the anode of the voltage stabilizing diode and the first end of the second capacitor and is grounded; The second end of the third resistor is respectively connected to the cathode of the voltage stabilizing diode and the second end of the second capacitor and sends a spiral current sampling signal to the control protection circuit; The sampling circuit further comprises: a cathode voltage sampling circuit; The cathode voltage sampling circuit comprises: fourth to tenth resistors, a third capacitor and a fourth capacitor; in, The first end of the third capacitor is connected to the anode of the tenth diode and the first end of the fourth resistor respectively; The second end of the fourth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the sixth resistor, the second end of the sixth resistor is connected to the first end of the seventh resistor, the second end of the seventh resistor is connected to the first end of the eighth resistor, and the second end of the eighth resistor is connected to the first end of the ninth resistor; The second end of the ninth resistor is respectively connected to the second end of the third capacitor, the first end of the tenth resistor and the first end of the fourth capacitor and sends a cathode voltage sampling signal to the control protection circuit; The second end of the fourth capacitor is connected to the second end of the tenth resistor and is grounded; The sampling circuit further comprises: an ignition current sampling circuit; The ignition current sampling circuit includes: a fifth capacitor, a sixth capacitor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a mutual inductor and an ignition current sampling circuit diode; The first end of the fifth capacitor is connected to the anode of the tenth diode, and the second end of the fifth capacitor is connected to the first end of the mutual inductor; The second end of the mutual inductor is grounded, the third end of the mutual inductor is connected to the first end of the eleventh resistor, and the fourth end of the mutual inductor is respectively connected to the first end of the twelfth resistor, the first end of the sixth capacitor, and the first end of the thirteenth resistor; The second end of the eleventh resistor is respectively connected to the second end of the twelfth resistor and the anode of the ignition current sampling circuit diode; The cathode of the ignition current sampling circuit diode is respectively connected to the second end of the sixth capacitor and the second end of the thirteenth resistor and sends an ignition current sampling signal to the control protection circuit; The control protection circuit is used to determine whether the power supply is abnormal according to the received signal, and control the opening and closing of the full-bridge inverter circuit through the drive circuit.

2. The power protection circuit according to claim 1, characterized in that: The power protection circuit further includes: a resonant circuit; The resonant circuit is used to receive the power supply voltage after the inversion of the full-bridge inverter circuit and to perform noise removal on the power supply voltage after the inversion of the full-bridge inverter circuit and then send it to the transformer.

3. The power protection circuit according to claim 1, characterized in that: The full-bridge inverter circuit includes four switch tubes, which are used to invert the DC voltage into a high-frequency AC square wave with a frequency of 100 kHz.

4. The power protection circuit according to claim 1, characterized in that: The voltage doubler rectifier circuit comprises: first to tenth diodes, first to tenth capacitors of the voltage doubler rectifier circuit, an inductor and first to third resistors of the voltage doubler rectifier circuit; in, The cathode of the first diode is connected to the first end of the first capacitor of the voltage doubler rectifier circuit; The anode of the first diode is connected to the first end of the second capacitor of the voltage doubler rectifier circuit and the cathode of the second diode respectively; The anode of the second diode is respectively connected to the second end of the first capacitor of the voltage doubler rectifier circuit, the cathode of the third diode and the first end of the third capacitor of the voltage doubler rectifier circuit; The anode of the third diode is respectively connected to the second end of the second capacitor of the voltage doubler rectifier circuit, the cathode of the fourth diode and the first end of the fourth capacitor of the voltage doubler rectifier circuit; The anode of the fourth diode is respectively connected to the second end of the third capacitor of the voltage doubler rectifier circuit, the cathode of the fifth diode, the first end of the fifth capacitor of the voltage doubler rectifier circuit and the first end of the first resistor of the voltage doubler rectifier circuit; The second end of the first resistor of the voltage doubler rectifier circuit serves as the first output end of the voltage doubler rectifier circuit; The anode of the fifth diode is respectively connected to the second end of the fourth capacitor of the voltage doubler rectifier circuit, the cathode of the sixth diode and the first end of the sixth capacitor of the voltage doubler rectifier circuit; The anode of the sixth diode is respectively connected to the second end of the fifth capacitor of the voltage doubler rectifier circuit, the first end of the inductor, the first end of the second resistor of the voltage doubler rectifier circuit, the cathode of the seventh diode and the first end of the eighth capacitor of the voltage doubler rectifier circuit; The second end of the second resistor of the voltage doubler rectifier circuit serves as the second output end of the voltage doubler rectifier circuit; The second end of the inductor is respectively connected to the second end of the sixth capacitor of the voltage doubler rectifier circuit and the first end of the seventh capacitor of the voltage doubler rectifier circuit; The anode of the seventh diode is respectively connected to the second end of the seventh capacitor of the voltage doubler rectifier circuit, the cathode of the eighth diode and the first end of the ninth capacitor of the voltage doubler rectifier circuit; The anode of the eighth diode is respectively connected to the second end of the eighth capacitor of the voltage doubler rectifier circuit, the first end of the third resistor of the voltage doubler rectifier circuit, the cathode of the ninth diode and the first end of the tenth capacitor of the voltage doubler rectifier circuit; The second end of the third resistor of the voltage doubler rectifier circuit serves as the third output end of the voltage doubler rectifier circuit; The anode of the ninth diode is connected to the second end of the ninth capacitor of the voltage doubler rectifier circuit and the cathode of the tenth diode respectively; The anode of the tenth diode is respectively connected to the second end of the tenth capacitor of the voltage doubler rectifier circuit and the first end of the protection resistor and serves as the fourth output end of the voltage doubler rectifier circuit.

5. The power protection circuit according to claim 1, characterized in that: The first resistor can be a 10Ω / 5W wire wound resistor or a resistance wire.

6. The power protection circuit according to claim 1, characterized in that: The turns ratio of the transformer is 1:

100.

7. The power protection circuit according to claim 1, characterized in that: The control and protection circuit includes a full-bridge control chip and a digital processing chip.

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