High-voltage discharge system with multiple protection functions and control method

Abstract

The invention relates to the technical field of high-voltage discharge, in particular to a high-voltage discharge system with a multi-protection function and a control method, high-voltage discharge multi-protection is realized through multi-circuit cooperation: a lighting switch circuit board converts 24V to 12V for a chip to work, and when VSample is higher than 10V, high voltage is cut off to prevent overvoltage of a xenon lamp; the peak absorption circuit board is driven to absorb reverse electromotive force to prevent breakdown by using an RCD network when the IGBT is turned off; the switching circuit generates SafeTrigger in real time, and the SafeTrigger is pulled down immediately to turn off the IGBT when the current exceeds 600A, the pulse exceeds 25ms and the like. The over-current protection circuit takes 8V as a threshold value, and is forcibly turned off to prevent the IGBT from being damaged when 600A; a pulse time length limiting circuit forcibly pulls down the SafeTrigger 25 ms later, and ultra-long pulses are completely eradicated; the time for limiting the turn-off of the IGBT is 15 microseconds, and the turn-off stability is ensured; when the over-temperature protection circuit is 70 DEG C, the signal is pulled down to close the drive; the constant current source feedback circuit amplifies and outputs as a current reference, maintains stable discharge, and improves the safety, reliability and service life of the system.

Description

Technical Field

[0001] This invention relates to the field of high-voltage discharge technology, and in particular to a high-voltage discharge system and control method with multiple protection functions. Background Technology

[0002] Currently, existing high-voltage discharge systems typically rely solely on single overcurrent or single hardware shutdown for protection, lacking a multi-layered coordinated protection mechanism for lamp ignition, overcurrent, pulse width, shutdown time, overtemperature, and voltage spikes. This leads to problems such as false ignition of xenon lamps, IGBT overcurrent damage, pulse timeout, insufficient shutdown time, inductor overheating, and shutdown spike breakdown, resulting in low system reliability. Summary of the Invention

[0003] The purpose of this invention is to provide a high-voltage discharge system and control method with multiple protection functions, aiming to solve the problem that the existing technology cannot achieve multiple coordinated protections such as automatic high-voltage cut-off when lighting lamps, rapid overcurrent protection, pulse width limitation, forced hold of turn-off time, over-temperature detection, and peak absorption.

[0004] To achieve the above objectives, in a first aspect, the present invention provides a high-voltage discharge system with multiple protection functions, including a lamp switch circuit board, a drive spike absorption circuit board, a switching circuit, an overcurrent protection circuit, a pulse duration limiting circuit, a circuit for limiting the IGBT shutdown duration, an over-temperature protection circuit, and a constant current source feedback circuit. The lamp switch circuit board is used to convert the external 24V voltage to 12V via N4LDO and supply it to the UC3844PWM chip. After being boosted by transformers T1 and T2, it outputs high voltage to light up the xenon lamp, and automatically cuts off the high voltage output when the sampled voltage V_Sample is higher than 10V. The drive spike absorption circuit board is used to perform RCD absorption of the reverse electromotive force generated by the inductor when the IGBT is turned off. The switching circuit is used to generate a Safe_Trigger signal during the effective period of the IGBT_Trigger pulse, and immediately pull down Safe_Trigger to turn off the IGBT when the current exceeds 600A, the pulse width exceeds 25ms, the turn-off time is less than 15μs, or an over-temperature signal is received. The overcurrent protection circuit is used to compare the voltage output by the LEMHAS-300S current sensor with the 8V reference voltage. When the current is greater than 600A, the Safe_Trigger is turned off through the thyristor V41. The pulse duration limiting circuit is used to output a high level through comparator N5A after IGBT_Trigger has been high for 25ms, forcibly pulling Safe_Trigger low. The circuit that limits the duration of IGBT shutdown is used to time a 15μs high level using NE555 to ensure that the duration of the Safe_Trigger low level is not less than 15μs. The over-temperature protection circuit is used to pull the SWM_OVER_TEMP signal low through the AIRPAX67F070 open element when the inductor temperature exceeds 70°C, so that the system can turn off Safe_Trigger accordingly. The constant current source feedback circuit is used to amplify the output voltage of the LEMHAS-300S by a 2.667 ratio using operational amplifier N6A, and then use it as a drive current reference to achieve closed-loop control of the lamp current. The lamp switch circuit board includes an N4 LDO, a UC3844 PWM chip, transformers T1 and T2, thyristors V28, V29, and V30, a comparator N2A, a MOSFET V17, transistors V20 and V21, thyristors V22, and V24.

[0005] The switching circuit includes transistor V35, transistor V36, resistor R41, and resistor R42.

[0006] The overcurrent protection circuit includes a comparator N7A, a transistor V42, and a thyristor V41.

[0007] The pulse duration limiting circuit includes a comparator N5A, a transistor V33, a resistor R30, a capacitor C24, and a diode V32.

[0008] The over-temperature protection circuit includes an AIRPAX,67F070 open-circuit element.

[0009] Secondly, a control method for a high-voltage discharge system with multiple protection functions, used in the high-voltage discharge system with multiple protection functions described in the first aspect, includes the following steps: S1: When the system is powered on, the N4 LDO converts the external 24V voltage to 12V and supplies it to the UC3844 PWM chip. The UC3844 starts up and outputs high voltage after being boosted by transformers T1 and T2, which lights up the xenon lamp. S2: Sample V_Sample in real time. If V_Sample is higher than 10V, proceed to step S3; otherwise, continue with S2. S3: By using comparator N2A, transistors V17, V18, V20, V21, thyristor V22, and transistor V24, the UC3844 PWM output is turned off, and the high voltage output stops. S4: Detect the rising edge of IGBT_Trigger, and the switching circuit generates a Safe_Trigger signal; S5: Compare the output voltage of the LEM HAS-300S current sensor with the 8V reference in real time. If the current is greater than 600 A, proceed to step S6. S6: The overcurrent protection circuit pulls Safe_Trigger low through thyristor V41 to turn off the IGBT; S7: Monitor the duration of the IGBT_Trigger high level in real time. If it lasts for more than 25 ms, the pulse duration limiting circuit outputs a high level through comparator N5A to force Safe_Trigger low and execute step S6. S8: The circuit that limits the IGBT turn-off time uses NE555 to time a 15 μs high level, and then uses transistor V39 to force the Safe_Trigger low to ensure that the IGBT turn-off time is not less than 15 μs; S9: Real-time detection of the status of the AIRPAX 67F070 open-circuit component attached to the inductor. If the inductor temperature exceeds 70 ℃, the SWM_OVER_TEMP signal is pulled low, the system immediately pulls low Safe_Trigger, and executes step S6. S10: During IGBT turn-off, the RCD network of the drive spike absorption circuit board absorbs the reverse electromotive force generated by the inductor. S11: Return to S4 and wait for the next IGBT_Trigger to be triggered.

[0010] This invention discloses a high-voltage discharge system with multiple protection functions. Through a lighting switch circuit board, the system only requires a 24V power supply to internally complete 12V conversion, PWM drive, and two-stage boost. It immediately cuts off the high voltage when V_Sample exceeds 10V to prevent overvoltage under no-load conditions for the xenon lamp, achieving one-time hardware self-protection during the lighting stage without software intervention. The drive spike absorption circuit board uses an RCD network to absorb the inductor's reverse electromotive force at the moment of IGBT turn-off, reducing voltage spikes, preventing secondary IGBT breakdown, and improving device lifespan. The switching circuit uses a single-wire Safe_Trigger to uniformly respond to four faults: overcurrent, ultra-wide pulse, insufficient turn-off time, and overtemperature. The Safe_Trigger is immediately pulled low upon the occurrence of any fault, achieving simultaneous turn-off for multiple faults, simplifying logic and providing a fast response. The overcurrent protection circuit directly utilizes the linear output of the LEMHAS-300S, comparing it with an 8V reference. The 600A hardware-triggered thyristor V41 operates on a 1μs-level basis, avoiding software sampling delay and ensuring that short circuits do not damage the IGBT. The pulse duration limiting circuit, through RC timing and comparator N5A, forces the pulse to terminate at 25ms in hardware, preventing energy accumulation from long pulses and avoiding xenon lamp overheating and power supply overload. The IGBT turn-off time limiting circuit utilizes NE555 to fix the output at a 15μs high level, forcing Safe_Trigger to remain low, ensuring minimum IGBT turn-off time, preventing half-bridge shoot-through, and improving system reliability. The over-temperature protection circuit uses an AIRPAX67F070 mechanical normally closed thermal switch, which pulls SWM_OVER_TEMP low upon opening at 70℃, requiring no additional power supply or sampling, achieving zero-power, zero-delay hardware over-temperature lockout. The constant current source feedback circuit amplifies the LEMHAS-300S output through a fixed-ratio 2.667 op-amp as the current reference, achieving hardware closed-loop lamp current, compensating for the negative resistance characteristics of the xenon lamp, maintaining stable luminescence, and providing real-time, accurate voltage samples for overcurrent protection. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 It is an LDO circuit; Figure 2 It is a current control circuit; Figure 3 It is a boost and high-voltage discharge protection circuit; Figure 4 It shuts down the high-voltage output circuit; Figure 5 It is a DC-DC circuit; Figure 6 It is a pulse trigger circuit; Figure 7 It is a current comparison circuit; Figure 8 It is a safety trigger protection circuit; Figure 9 It is a circuit that protects the IGBT turn-off time. Figure 10 It is a temperature control switch connection circuit; Figure 11 It is a temperature control switch voltage divider circuit; Figure 12 It is an IGBT driver circuit; Figure 13 It is an RCD spike absorption circuit; Figure 14 This is a flowchart of a control method for a high-voltage discharge system with multiple protection functions provided by the present invention. Detailed Implementation

[0013] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0014] Please see Figures 1 to 13 In a first aspect, the present invention provides a high-voltage discharge system with multiple protection functions, including a lamp switch circuit board, a drive spike absorption circuit board, a switch circuit, an overcurrent protection circuit, a pulse duration limiting circuit, a circuit for limiting the IGBT shutdown duration, an over-temperature protection circuit, and a constant current source feedback circuit. The lamp switch circuit board is used to convert the external 24V voltage to 12V via N4LDO and supply it to the UC3844PWM chip. After being boosted by transformers T1 and T2, it outputs high voltage to light up the xenon lamp, and automatically cuts off the high voltage output when the sampled voltage V_Sample is higher than 10V. The drive spike absorption circuit board is used to perform RCD absorption of the reverse electromotive force generated by the inductor when the IGBT is turned off. The switching circuit is used to generate a Safe_Trigger signal during the effective period of the IGBT_Trigger pulse, and immediately pull down Safe_Trigger to turn off the IGBT when the current exceeds 600A, the pulse width exceeds 25ms, the turn-off time is less than 15μs, or an over-temperature signal is received. The overcurrent protection circuit is used to compare the voltage output by the LEMHAS-300S current sensor with the 8V reference voltage. When the current is greater than 600A, the Safe_Trigger is turned off through the thyristor V41. The pulse duration limiting circuit is used to output a high level through comparator N5A after IGBT_Trigger has been high for 25ms, forcibly pulling Safe_Trigger low. The circuit that limits the duration of IGBT shutdown is used to time a 15μs high level using NE555 to ensure that the duration of the Safe_Trigger low level is not less than 15μs. The over-temperature protection circuit is used to pull the SWM_OVER_TEMP signal low through the AIRPAX67F070 open element when the inductor temperature exceeds 70°C, so that the system can turn off Safe_Trigger accordingly. The constant current source feedback circuit is used to amplify the output voltage of the LEMHAS-300S by a 2.667 ratio using operational amplifier N6A, and then use it as a drive current reference to achieve closed-loop control of the lamp current. The lamp switch circuit board includes an N4 LDO, a UC3844 PWM chip, transformers T1 and T2, thyristors V28, V29, and V30, a comparator N2A, a MOSFET V17, transistors V20 and V21, thyristors V22, and V24.

[0015] Furthermore, the switching circuit includes transistor V35, transistor V36, resistor R41, and resistor R42.

[0016] Furthermore, the overcurrent protection circuit includes a comparator N7A, a transistor V42, and a thyristor V41.

[0017] Furthermore, the pulse duration limiting circuit includes a comparator N5A, a transistor V33, a resistor R30, a capacitor C24, and a diode V32.

[0018] Furthermore, the over-temperature protection circuit includes an AIRPAX,67F070 open-circuit element.

[0019] In this embodiment, the high-voltage lighting circuit: The lighting circuit starts by providing 24V voltage, which is then converted from +24V to +12V by the N4 LDO. This activates the N1 UC3844 PWM chip controller, which drives the Q1 switch, causing a change in the primary voltage of T1. (The following...) Figure 1When the PWM output at pin 6 of N1 is high, the voltage flows through drive resistor R3 and diode D40 to the gate of Q1. Since Q40 is a PNP transistor, it is cut off, and the gate of Q1 is high, causing Q1 to conduct. Q40, being a PNP transistor, accelerates turn-off, and R91 limits current. R90 is a bleeder resistor. Simultaneously, C11 / C12 connected to the secondary side of T1 charges. At the same time, the voltages of V8 / V9 / V10 rise to the threshold voltage of trigger thyristors V28 / V29 / V30, causing them to conduct and discharging C11 / C12 to ground, thus generating a pulse voltage. This generates a voltage between pins 1 and 10 of transformer T2. Due to the large turns ratio of transformer T2, a high voltage is generated, which is directly output to the xenon lamp, illuminating it. If the output line to the xenon lamp is disconnected, the high voltage will be discharged by detonators V11 / V12 / V13. Additionally, the V_Sample sampling voltage between pins 7 and 10 of T1 is sent to comparator N2A and compared with the 10V voltage at pin 3 of N2A. If the sampling voltage is higher than 10V, pin 1 of N2A outputs a low level, and MOSFET V17 is not turned on.

[0020] Automatic high-voltage lamp-lighting circuit cutoff: Simultaneously, V18 is not conducting. The base voltage of transistor V20, from +12V, charges C40 through R18 until the voltage of C40 rises to a level sufficient to turn on V20. This causes the base of V21 to be low, preventing V21 from conducting. This triggers the threshold voltage of thyristor V22 to be high, causing V22 to conduct. Ultimately, this turns on V24, making pin 1 of N1 conduct to ground, thus stopping the PWM output of N1, and consequently stopping the high-voltage output. In this circuit, C40 is an electrolytic capacitor, so the values ​​of C40 and R18 determine the duration of the high-voltage discharge. If the sampling voltage V_Sample is below 10V, pin 1 of N2A.1 will output a high level, causing V17 to conduct and HVR_GND to go low (a low HVR_GND signal activates the system relay). Simultaneously, a high level at pin N2A.1 results in a high level at the base of V18, causing V18 to conduct. This pulls down the base voltage of V20, preventing V20 from conducting. Consequently, a high level at the base of V21 causes V21 to conduct, resulting in a low threshold voltage for thyristor V22, preventing V22 from conducting. Since the cathode of diode V24 is connected to +12V, the voltage at pin N1.1 is unaffected. By connecting an external RC network to this pin and the FB pin, the feedback loop is compensated, ensuring stable output.

[0021] The switching circuit works as follows: During the high-level period of an external IGBT_Trigger pulse, the IGBT completes the switching process, and the signal at this time is called Safe_Trigger. To ensure the safety of the Safe_Trigger signal, a multiple triggering circuit was implemented, and the circuit was converted from +24V to ±15V. The circuit is as follows: Figure 3 Switching circuits such as Figure 4 (Safe_Trigger Trigger) When the IGBT_Trigger pulse signal is high, it passes through R41 and R42 to NPN transistor V35, turning V35 on and thus turning off transistor V36. Therefore, Safe_Trigger is in the triggered state. If the IGBT_Trigger signal is low, transistor V35 is off, and V36 is on, pulling the Safe_Trigger signal low, thus stopping the trigger.

[0022] Constant current source feedback circuit: During the IGBT_Trigger pulse time, the switching circuit compares the current generated by the current sensor with the current flowing through it, thereby directly outputting a high or low level, causing the IGBT to turn on or off via the Safe_Trigger signal. The circuit is as follows: Figure 5 A current sensor, model LEM HAS-300S, is used in the switching circuit. This current sensor is linear; when it detects a current of 300A, its output voltage is 4V; when it detects a current of 600A, the output voltage is 8V. Therefore, the ratio of the op-amp N6A in the circuit is 2.667. Assuming the current flowing through the current sensor is 300A, the voltage across Lamp_Current is 4V; therefore, the voltage at pin 5 of N6B should also be 4V; so the voltage at pin 1 of N6A should be 4V / 2.667 = 1.49V (the ratio of the N6A op-amp is 2.667). If the current flowing through the current sensor is 600A, the voltage across Lamp_Current is 8V. Therefore, the voltage at pin 5 of N6B should also be 8V, so the voltage at pin 1 of N6A should be 8V / 2.667 = 2.99V. The voltage at pin 1 of N6A is the voltage value of the drive current, which is given externally (e.g., circuit). Figure 5 ).

[0023] Overcurrent protection circuit: 600A current limiting switching circuit, its circuit is as follows: Figure 6 Assuming a current of 600A, the voltage output from the current sensor is 8V, which is compared with the 8V reference voltage at pin 3 of comparator N7A. If the current exceeds 600A, the current sensor output voltage exceeds 8V, resulting in a low-level output at pin 1 of N7A. This disconnects transistor V42, opening the threshold voltage of thyristor V41, causing V41 to conduct. Consequently, the base of transistor V35 goes low, disconnecting V35, and the base of transistor V36 goes high, turning V36 on. Therefore, the Safe_Trigger signal is pulled low, stopping the IGBT trigger.

[0024] Pulse duration limiting circuit: The switching circuit limits the pulse duration to 25ms, and its circuit is as follows: Figure 7 The voltage at pin 2 of N5A is 15V * 1.5K / 11.5K = 1.956V. When there is a pulse signal from the IGBT_Trigger, after passing through V32 and R30, C24 in the RC circuit begins to charge. When the voltage across C24 rises above 1.956V, the time elapsed is 25ms. Therefore, when the IGBT_Trigger pulse high level exceeds 25ms, the output of pin 1 of N5A goes high, turning on transistor V33 and directly pulling the Safe_Trigger signal low, thus stopping the IGBT.

[0025] Circuit for limiting IGBT turn-off time: The IGBT turn-off time in the switching circuit is no less than 15µs, determined by the 15µs high-level output of the N9 clock chip NE555. During this time, V39 is turned on, and pin 3.3 of V39 is pulled low. Consequently, V35 is turned off, the base of V36 is high, and V36 is turned on. This ensures a 15µs low-level time for the Safe_Trigger. The circuit diagram is as follows. Figure 8 ; Over-temperature protection circuit: An AIRPAX 67F070 open-circuit component is placed on the inductor. When the inductor overheats above 70°C, this component automatically shuts down. One pin of this connector is grounded, thus changing the SWM_OVER_TEMP signal from high level to low level. This signal is then input to the system for processing.

[0026] IGBT driver circuit: The driver circuit is isolated by an N1 optocoupler HCPL-3101 and drives the MOSFET. The circuit is as follows: Figure 11 ; RCD snubber circuit: When the IGBT is turned off, the inductor will generate a directional electromotive force, so an RCD snubber circuit is needed.

[0027] Please see Figure 14 Secondly, a control method for a high-voltage discharge system with multiple protection functions, used in the high-voltage discharge system with multiple protection functions described in the first aspect, includes the following steps: S1: When the system is powered on, the N4 LDO converts the external 24V voltage to 12V and supplies it to the UC3844 PWM chip. The UC3844 starts up and outputs high voltage after being boosted by transformers T1 and T2, which lights up the xenon lamp. S2: Sample V_Sample in real time. If V_Sample is higher than 10V, proceed to step S3; otherwise, continue with S2. S3: By using comparator N2A, transistors V17, V18, V20, V21, thyristor V22, and transistor V24, the UC3844 PWM output is turned off, and the high voltage output stops. S4: Detect the rising edge of IGBT_Trigger, and the switching circuit generates a Safe_Trigger signal; S5: Compare the output voltage of the LEM HAS-300S current sensor with the 8V reference in real time. If the current is greater than 600 A, proceed to step S6. S6: The overcurrent protection circuit pulls Safe_Trigger low through thyristor V41 to turn off the IGBT; S7: Monitor the duration of the IGBT_Trigger high level in real time. If it lasts for more than 25 ms, the pulse duration limiting circuit outputs a high level through comparator N5A to force Safe_Trigger low and execute step S6. S8: The circuit that limits the IGBT turn-off time uses NE555 to time a 15 μs high level, and then uses transistor V39 to force the Safe_Trigger low to ensure that the IGBT turn-off time is not less than 15 μs; S9: Real-time detection of the status of the AIRPAX 67F070 open-circuit component attached to the inductor. If the inductor temperature exceeds 70 ℃, the SWM_OVER_TEMP signal is pulled low, the system immediately pulls low Safe_Trigger, and executes step S6. S10: During IGBT turn-off, the RCD network of the drive spike absorption circuit board absorbs the reverse electromotive force generated by the inductor. S11: Return to S4 and wait for the next IGBT_Trigger to be triggered.

[0028] The above description is merely a preferred embodiment of a high-voltage discharge system and control method with multiple protection functions according to the present invention. It should not be construed as limiting the scope of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiments can be implemented, and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A high-voltage discharge system with multiple protection functions, characterized in that, It includes a lighting switch circuit board, a drive spike absorption circuit board, a switching circuit, an overcurrent protection circuit, a pulse duration limiting circuit, a circuit for limiting the IGBT turn-off time, an over-temperature protection circuit, and a constant current source feedback circuit; The lamp switch circuit board is used to convert the external 24V voltage to 12V via N4LDO and supply it to the UC3844PWM chip. After being boosted by transformers T1 and T2, it outputs high voltage to light up the xenon lamp, and automatically cuts off the high voltage output when the sampled voltage V_Sample is higher than 10V. The drive spike absorption circuit board is used to perform RCD absorption of the reverse electromotive force generated by the inductor when the IGBT is turned off. The switching circuit is used to generate a Safe_Trigger signal during the effective period of the IGBT_Trigger pulse, and immediately pull down Safe_Trigger to turn off the IGBT when the current exceeds 600A, the pulse width exceeds 25ms, the turn-off time is less than 15μs, or an over-temperature signal is received. The overcurrent protection circuit is used to compare the voltage output by the LEMHAS-300S current sensor with the 8V reference voltage. When the current is greater than 600A, the Safe_Trigger is turned off through the thyristor V41. The pulse duration limiting circuit is used to output a high level through comparator N5A after IGBT_Trigger has been high for 25ms, forcibly pulling Safe_Trigger low. The circuit that limits the duration of IGBT shutdown is used to time a 15μs high level using NE555 to ensure that the duration of the Safe_Trigger low level is not less than 15μs. The over-temperature protection circuit is used to pull the SWM_OVER_TEMP signal low through the AIRPAX67F070 open element when the inductor temperature exceeds 70°C, so that the system can turn off Safe_Trigger accordingly. The constant current source feedback circuit is used to amplify the output voltage of LEMHAS-300S by the operational amplifier N6A at a ratio of 2.667 and use it as a reference for the drive current to achieve closed-loop control of the lamp current.

2. The high-voltage discharge system with multiple protection functions as described in claim 1, characterized in that, The lighting switch circuit board consists of a lighting circuit and a switching circuit.

3. The high-voltage discharge system with multiple protection functions as described in claim 2, characterized in that, The lighting switch circuit board includes an N4 LDO, a UC3844 PWM chip, a transformer T1, a transformer T2, a thyristor V28, a thyristor V29, a thyristor V30, a comparator N2A, a MOSFET V17, a transistor V20, a transistor V21, a thyristor V22, and a transistor V24.

4. The high-voltage discharge system with multiple protection functions as described in claim 2, characterized in that, The switching circuit includes transistor V35, transistor V36, resistor R41, and resistor R42.

5. The high-voltage discharge system with multiple protection functions as described in claim 1, characterized in that, The overcurrent protection circuit includes a comparator N7A, a transistor V42, and a thyristor V41.

6. The high-voltage discharge system with multiple protection functions as described in claim 1, characterized in that, The pulse duration limiting circuit includes a comparator N5A, a transistor V33, a resistor R30, a capacitor C24, and a diode V32.

7. The high-voltage discharge system with multiple protection functions as described in claim 1, characterized in that, The over-temperature protection circuit includes an AIRPAX 67F070 open-circuit element.

8. A control method for a high-voltage discharge system with multiple protection functions, used in the high-voltage discharge system with multiple protection functions as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: When the system is powered on, the N4 LDO converts the external 24V voltage to 12V and supplies it to the UC3844 PWM chip. The UC3844 starts up and outputs high voltage after being boosted by transformers T1 and T2, which lights up the xenon lamp. S2: Sample V_Sample in real time. If V_Sample is higher than 10V, proceed to step S3; otherwise, continue with S2. S3: By using comparator N2A, transistors V17, V18, V20, V21, thyristor V22, and transistor V24, the UC3844 PWM output is turned off, and the high voltage output stops. S4: Detect the rising edge of IGBT_Trigger, and the switching circuit generates a Safe_Trigger signal; S5: Compare the output voltage of the LEM HAS-300S current sensor with the 8V reference in real time. If the current is greater than 600 A, proceed to step S6. S6: The overcurrent protection circuit pulls Safe_Trigger low through thyristor V41 to turn off the IGBT; S7: Monitor the duration of the IGBT_Trigger high level in real time. If it lasts for more than 25 ms, the pulse duration limiting circuit outputs a high level through comparator N5A to force Safe_Trigger low and execute step S6. S8: The circuit that limits the IGBT turn-off time uses NE555 to time a 15 μs high level, and then uses transistor V39 to force the Safe_Trigger low to ensure that the IGBT turn-off time is not less than 15 μs; S9: Real-time detection of the status of the AIRPAX 67F070 open-circuit component attached to the inductor. If the inductor temperature exceeds 70 ℃, the SWM_OVER_TEMP signal is pulled low, the system immediately pulls low Safe_Trigger, and executes step S6. S10: During IGBT turn-off, the RCD network of the drive spike absorption circuit board absorbs the reverse electromotive force generated by the inductor. S11: Return to S4 and wait for the next IGBT_Trigger to be triggered.

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