A xenon lamp high-voltage trigger and pre-ignition maintenance integrated circuit and design method

Abstract

The application provides a xenon lamp high-voltage trigger and pre-ignition maintenance integrated circuit and a design method, and relates to the field of xenon lamp driving power supplies. The circuit generates a driving signal through a high-frequency driving unit, and a high-frequency power conversion unit converts input electric energy into high-frequency electric energy accordingly, and an LCC resonant conversion unit converts and transmits electric energy through a high-frequency transformer. A high-voltage trigger branch and a pre-ignition maintenance branch are coupled to the same high-frequency transformer output side, the former provides a trigger voltage to an unbroken xenon lamp through a multi-stage diode-capacitor voltage doubling structure, and the latter provides pre-ignition maintenance electric energy to a broken xenon lamp through rectification. A state sampling and control unit determines the working state according to xenon lamp voltage and current sampling information, and adjusts the driving signal and transmission electric energy, thereby realizing the integration and continuity of high-voltage trigger and pre-ignition maintenance, simplifying the circuit structure, and improving the stage connection and pre-ignition maintenance stability.

Description

Technical Field

[0001] This application relates to the field of xenon lamp drive power supply technology, and in particular to an integrated circuit and design method for xenon lamp high voltage triggering and pre-ignition maintenance. Background Technology

[0002] Xenon lamps are characterized by high brightness, a wide spectral range, and high instantaneous output energy, and are widely used in laser light sources, pulsed lighting, optical detection, and pulsed power devices. During the operation of high-power xenon lamps, a high voltage is typically applied first to break down the gas inside the lamp and form a conductive channel. Then, pre-ignition power is used to maintain the ionization state within the lamp, providing stable initial conditions for subsequent pulsed discharge. The reliability of the high-voltage triggering and pre-ignition maintenance processes directly affects the success rate of xenon lamp ignition, continuous operation stability, and the effect of subsequent pulsed discharge.

[0003] In related technologies, xenon lamp power supplies typically employ separate high-voltage triggering circuits and pre-ignition sustaining circuits. The high-voltage triggering circuit generates the trigger voltage required for xenon lamp breakdown, while the pre-ignition sustaining circuit provides the corresponding sustaining voltage and current after the xenon lamp is lit. Simultaneously, drive control circuits and voltage and current detection circuits control and monitor the xenon lamp's operation. However, xenon lamps exhibit significantly different nonlinear load characteristics before and after triggering, and their operating state is also affected by factors such as input power supply fluctuations, component parameter deviations, and changes in operating conditions. Existing high-voltage triggering circuits and pre-ignition sustaining circuits often lack effective coordination, easily leading to complex circuit structures, insufficient parameter adaptability, and potential problems such as unstable trigger voltage, fluctuating pre-ignition sustaining current, and unreliable connections between different operating stages, thus affecting the operational stability and safety of the xenon lamp power supply.

[0004] Therefore, in the high-voltage triggering and pre-ignition maintenance process of high-power high-pressure xenon lamps, how to improve the adaptability of triggering power supply and pre-ignition power supply to changes in xenon lamp load state while taking into account circuit integration and operational safety, and ensuring reliable connection between the triggering, pre-ignition and subsequent discharge stages, has become an urgent problem to be solved. Summary of the Invention

[0005] This application provides an integrated circuit and design method for high-voltage triggering and pre-ignition maintenance of a xenon lamp, aiming to solve the technical problems of complex circuit structure, untimely connection of working stages, and insufficient stability of pre-ignition maintenance caused by the independent high-voltage triggering function and pre-ignition maintenance function in existing xenon lamp drive circuits.

[0006] In a first aspect, this application provides an integrated circuit for high-voltage triggering and pre-combustion maintenance of a xenon lamp, the circuit comprising: A high-frequency drive unit is used to generate a high-frequency drive signal and adjust the high-frequency drive signal according to a drive adjustment command; A high-frequency power conversion unit, connected to the high-frequency drive unit, is used to perform high-frequency conversion on the input electrical energy according to the high-frequency drive signal to obtain high-frequency electrical energy. The LCC resonant converter unit, connected to the high-frequency power conversion unit, includes a resonant network and a high-frequency transformer, and is used to resonantly convert the high-frequency electrical energy and transmit the resonant converted electrical energy to the output side of the high-frequency transformer. Both the high-voltage triggering branch and the pre-ignition sustaining branch are coupled to the output side of the same high-frequency transformer and connected to the xenon lamp; wherein, the high-voltage triggering branch includes a multi-stage diode-capacitor voltage multiplier structure, used to provide trigger voltage to the xenon lamp that has not broken down; the pre-ignition sustaining branch is used to rectify the electrical energy output by the high-frequency transformer and provide pre-ignition sustaining electrical energy to the xenon lamp that has broken down; The status sampling and control unit is connected to the xenon lamp and the high-frequency drive unit, respectively, and is used to acquire xenon lamp voltage sampling information and xenon lamp current sampling information, determine the xenon lamp operating status based on the xenon lamp voltage sampling information and xenon lamp current sampling information, and generate the drive adjustment command based on the xenon lamp operating status to adjust the electrical energy transmitted to the high-voltage trigger branch and the pre-combustion sustaining branch through the high-frequency transformer.

[0007] In one possible design, the output side of the high-frequency transformer forms a first energy transmission path and a second energy transmission path; The first energy transmission path connects the high-frequency transformer and the high-voltage trigger branch, and is used to transmit the electrical energy output by the high-frequency transformer to the multi-stage diode-capacitor voltage multiplier structure; The second energy transmission path connects the high-frequency transformer and the pre-combustion sustaining branch, and is used to transmit the electrical energy output by the high-frequency transformer to the pre-combustion sustaining branch; The output terminals of the high-voltage triggering branch and the pre-combustion sustaining branch are respectively connected to the xenon lamp, so that the first energy transmission path and the second energy transmission path share the high-frequency transformer and respectively undertake the triggering power transmission and the pre-combustion sustaining power transmission.

[0008] In one possible design, the multi-stage diode-capacitor voltage multiplier structure includes multiple cascaded boost units, each of which includes a diode and a capacitor. The boost units are connected in a manner that rectifies, stores, and superimposes the electrical energy transmitted through the first energy transmission path. The number of stages in the boost unit and the capacitance value of each capacitor are configured according to the minimum trigger voltage of the xenon lamp, the input voltage of the first energy transmission path, the trigger load current, the high-frequency drive frequency, and the allowable voltage ripple, so that the output voltage of the multi-stage diode-capacitor voltage multiplier structure under the trigger load condition is not lower than the minimum trigger voltage of the xenon lamp. The high-voltage triggering branch also includes a high-resistance network connected between the output terminal of the multi-stage diode-capacitor voltage multiplier structure and the xenon lamp. The high-resistance network is used to adjust the triggering voltage and release the residual charge after the xenon lamp breaks down.

[0009] In one possible design, the resonant network includes a series resonant inductor, a series resonant capacitor, and a parallel resonant capacitor; The series resonant inductor and the series resonant capacitor are connected in series between the output terminal of the high-frequency power conversion unit and the input terminal of the high-frequency transformer, and the parallel resonant capacitor is connected to the input terminal of the high-frequency transformer. The pre-combustion sustaining branch includes a rectifier circuit and an output filter energy storage element. The input terminal of the rectifier circuit is connected to the output side of the high-frequency transformer, and the output terminal of the rectifier circuit is connected to the xenon lamp via the output filter energy storage element to obtain the pre-combustion sustaining electrical energy supplied to the xenon lamp.

[0010] In one possible design, the turns ratio of the high-frequency transformer is configured according to the input voltage range of the high-frequency power conversion unit and the target voltage for xenon lamp pre-ignition. The inductance value of the series resonant inductor, the capacitance value of the series resonant capacitor, and the capacitance value of the parallel resonant capacitor are configured according to the xenon lamp pre-ignition target voltage, the xenon lamp pre-ignition target current, and the dynamic resistance characteristics of the xenon lamp pre-ignition stage, so as to form a resonant circuit impedance that is compatible with the dynamic resistance characteristics. The switching frequency of the high-frequency drive unit is configured according to the resonant frequency determined by the series resonant inductor and the series resonant capacitor, so that the pre-ignition sustaining voltage and pre-ignition sustaining current output by the LCC resonant converter unit cover the xenon lamp pre-ignition target voltage and the xenon lamp pre-ignition target current.

[0011] In one possible design, the high-frequency drive unit includes a pulse width modulation controller, an isolation drive circuit, and a gate drive network; The pulse width modulation controller is used to generate a first pulse width modulation signal and a second pulse width modulation signal having a preset phase relationship and a dead time according to the drive adjustment command; The isolation drive circuit is used to electrically isolate and drive the first pulse width modulation signal and the second pulse width modulation signal respectively, to obtain a first isolation drive signal and a second isolation drive signal; The gate drive network is used to generate a first gate drive signal and a second gate drive signal based on the first isolation drive signal and the second isolation drive signal, and to provide the first gate drive signal and the second gate drive signal to the power switching device in the high-frequency power conversion unit, respectively.

[0012] In one possible design, the pulse width modulation controller is further configured to adjust the pulse widths of the first pulse width modulation signal and the second pulse width modulation signal according to a soft-start timing sequence; The gate drive network includes a gate damping branch, a gate overvoltage suppression branch, and a gate charge release branch. The gate damping branch is used to suppress gate oscillation of the power switching device, the gate overvoltage suppression branch is used to limit the gate drive voltage, and the gate charge release branch is used to release gate charge during the turn-off process. The first isolation drive signal and the second isolation drive signal are processed by the gate drive network to form the first gate drive signal and the second gate drive signal provided to the corresponding power switching devices.

[0013] In one possible design, the state sampling and control unit is configured as follows: Obtain the pre-ignition start command, the power supply unit operating status, and the energy storage circuit status, and determine the pre-ignition start conditions based on the power supply unit operating status and the energy storage circuit status; If the pre-ignition start-up conditions are met, an initial drive adjustment command is generated, and the xenon lamp voltage sampling information and the xenon lamp current sampling information are acquired. The xenon lamp voltage sampling information and the xenon lamp current sampling information are compared with the corresponding state judgment thresholds to obtain the pre-ignition completion judgment result, and the xenon lamp working state is determined based on the pre-ignition completion judgment result. If the pre-ignition completion determination result is not completed, an updated drive adjustment command is generated based on the deviation between the xenon lamp voltage sampling information and the xenon lamp current sampling information and the corresponding state determination threshold. If the pre-combustion completion determination result is "complete", pre-combustion completion information is generated.

[0014] In one possible design, the circuit further includes a downstream power loop and an isolation control unit, the isolation control unit being connected to the state sampling and control unit for controlling the on / off state of the downstream power loop according to loop control commands; The state sampling and control unit is also configured to: start the pre-ignition timing when the initial drive adjustment command is generated, and obtain the pre-ignition duration; If the pre-ignition completion information is generated before the pre-ignition duration reaches the preset timeout time, a circuit connection command for connecting the subsequent power circuit is generated after a preset delay time. If the pre-ignition duration reaches the preset timeout period and the pre-ignition completion information is not generated, a pre-ignition stop command is generated to stop the high-frequency drive unit and the pre-ignition retry count is updated. When the updated number of pre-ignition retry attempts does not reach the preset maximum number of retry attempts and the preset retry interval is met, a pre-ignition restart command for restarting the high-frequency drive unit is generated. When the updated number of pre-ignition retries reaches the preset maximum number of retries, a pre-ignition failure message and a circuit disconnection command for disconnecting the subsequent power circuit are generated to keep the subsequent power circuit in a disconnected state.

[0015] Secondly, this application provides a structural and parameter design method for an integrated circuit for high-voltage triggering and pre-ignition maintenance of a xenon lamp, the method comprising: Obtain circuit design information, which includes input voltage range, minimum trigger voltage of xenon lamp, target voltage for xenon lamp pre-ignition, target current for xenon lamp pre-ignition, dynamic resistance characteristics of xenon lamp pre-ignition stage, high-frequency power conversion drive constraints, and xenon lamp state determination conditions. Based on the minimum trigger voltage of the xenon lamp and the input parameters of the trigger branch in the circuit design information, the number of voltage multiplication stages, capacitor parameters, and high-impedance network parameters of the multi-stage diode-capacitor voltage multiplication structure are determined to obtain the design results of the high-voltage trigger branch. Based on the input voltage range, the xenon lamp pre-ignition target voltage, the xenon lamp pre-ignition target current, and the dynamic resistance characteristics, the resonance parameters of the LCC resonant network, the turns ratio of the high-frequency transformer, and the rectification configuration of the pre-ignition sustaining branch are determined, and the design results of the pre-ignition sustaining branch are obtained. Based on the design results of the high-voltage triggering branch and the pre-ignition sustaining branch, a first energy transmission path and a second energy transmission path connecting the high-voltage triggering branch and the pre-ignition sustaining branch are determined on the output side of the same high-frequency transformer, and the connection relationship between the high-voltage triggering branch, the pre-ignition sustaining branch and the xenon lamp is determined to obtain the integrated output structure design result. Based on the resonance parameters and the high-frequency power conversion drive constraints, the switching control requirements of the high-frequency power conversion unit, the high-frequency drive parameters, and the drive relationship between the high-frequency drive signal and the high-frequency power conversion unit are determined, and the drive conversion design results are obtained. Based on the xenon lamp state determination conditions, xenon lamp voltage sampling parameters, xenon lamp current sampling parameters, and the drive conversion design results, the feedback control relationship between the xenon lamp working state and the drive adjustment parameters is determined, and the state feedback control design results are obtained. Based on the design results of the high-voltage triggering branch, the design results of the pre-ignition sustaining branch, the design results of the integrated output structure, the design results of the drive conversion, and the design results of the state feedback control, the structure and parameters of the integrated circuit for xenon lamp high-voltage triggering and pre-ignition sustaining are configured to obtain the integrated circuit design results.

[0016] This application provides an integrated circuit and design method for xenon lamp high-voltage triggering and pre-ignition maintenance. The circuit generates and adjusts a high-frequency drive signal through a high-frequency drive unit, causing a high-frequency power conversion unit to convert input electrical energy into high-frequency electrical energy. This high-frequency electrical energy is then resonantly converted by an LCC resonant converter and transmitted to the output side via a high-frequency transformer, thus forming a high-frequency energy transmission foundation capable of simultaneously meeting the needs of xenon lamp triggering and pre-ignition maintenance. By coupling the high-voltage triggering branch and the pre-ignition maintenance branch to the same output side of the high-frequency transformer, the multi-stage diode-capacitor voltage multiplier structure can boost the electrical energy output from the high-frequency transformer and provide a trigger voltage to the xenon lamp when the xenon lamp is not broken down. Simultaneously, the pre-ignition maintenance branch can rectify the electrical energy output from the high-frequency transformer and provide pre-ignition maintenance energy to the xenon lamp after the xenon lamp breaks down. Therefore, the high-frequency power conversion and pre-ignition maintenance circuits are integrated into a single high-frequency power conversion unit. The transformer transmission link achieves coordinated configuration of high-voltage triggering and pre-ignition maintenance functions, reducing the complexity of circuit structure and poor energy transfer caused by setting up separate independent energy conversion links. Furthermore, the xenon lamp voltage and current sampling information are obtained through the state sampling and control unit. Based on this, the xenon lamp operating state is determined and drive adjustment commands are generated. This allows the high-frequency drive unit to adjust the high-frequency drive signal according to the change of the xenon lamp from the non-breakdown state to the pre-ignition state after breakdown. In turn, it adjusts the electrical energy transmitted to the high-voltage triggering branch and the pre-ignition maintenance branch through the high-frequency transformer, so that the circuit output is adapted to the operating state of the xenon lamp. Ultimately, the high-voltage triggering and pre-ignition maintenance process of the xenon lamp are integrated and continuous, improving the problems of structural complexity, untimely connection of working stages, and insufficient pre-ignition maintenance stability caused by the independence of the existing triggering circuit and pre-ignition maintenance circuit. Attached Figure Description

[0017] Figure 1 A circuit block diagram of an integrated circuit for high-voltage triggering and pre-ignition maintenance of a xenon lamp, provided in an embodiment of this application; Figure 2 A topology diagram of a multi-stage diode-capacitor voltage multiplier structure provided in this application embodiment; Figure 3 A circuit diagram illustrating a multi-stage diode-capacitor voltage multiplier structure provided in this application embodiment; Figure 4 A schematic diagram of the circuit structure of a high-frequency power conversion unit, an LCC resonant conversion unit, and a pre-combustion sustaining branch provided for embodiments of this application; Figure 5(a) is one of the circuit structure schematic diagrams of a high-frequency driving unit provided in an embodiment of this application; Figure 5(b) is a second schematic diagram of the circuit structure of a high-frequency driving unit provided in an embodiment of this application; Figure 6 This is a schematic diagram of a pre-combustion sustained high-pressure isolation control structure provided in an embodiment of this application; Figure 7 A flowchart illustrating the operation of a xenon lamp pre-ignition sustaining circuit provided in an embodiment of this application; Figure 8 This is a schematic diagram of a xenon lamp pre-ignition control and pre-ignition completion feedback circuit provided in an embodiment of this application; Figure 9 A simulation waveform diagram of a xenon lamp high-voltage triggering process provided in an embodiment of this application; Figure 10 A simulation waveform diagram of the pre-combustion maintenance process of a xenon lamp provided in an embodiment of this application; Figure 11 An experimental waveform diagram of a xenon lamp high-voltage triggering process provided in an embodiment of this application; Figure 12 Experimental waveforms of xenon lamp pre-ignition sustaining voltage, pre-ignition sustaining current, and equivalent resistance under low-frequency pre-ignition conditions provided in this application embodiment; Figure 13 A pulse discharge experimental waveform diagram under low-frequency pre-ignition conditions is provided for an embodiment of this application; Figure 14 Experimental waveforms of xenon lamp pre-ignition sustaining voltage, pre-ignition sustaining current, and equivalent resistance under high-frequency pre-ignition conditions provided in this application embodiment; Figure 15 This is a waveform diagram of a pulse discharge experiment under high-frequency pre-ignition conditions provided in an embodiment of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having” and any variations thereof in the documents of this application are intended to cover non-exclusive inclusion.

[0020] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of the phrase "embodiment" in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0021] In this article, the term "and / or" simply describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists, A and B can exist simultaneously, and B exists. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0022] Furthermore, the terms "first," "second," etc., used in this application are used to distinguish different objects rather than to describe a specific order, and may explicitly or implicitly include one or more of the features.

[0023] In the description of this application, unless otherwise stated, "multiple" and "at least two" mean two or more (including two), and similarly, "multiple groups" and "at least two groups" mean two or more (including two groups).

[0024] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, "connected" or "linked" can refer not only to a physical connection, but also to an electrical connection or a signal connection. For instance, it can be a direct connection, i.e., a physical connection, or an indirect connection through at least one intermediate component, as long as the circuit is connected. It can also refer to the internal connection between two components. A signal connection can refer not only to a signal connection through a circuit, but also to a signal connection through a medium, such as radio waves. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0025] To enable those skilled in the art to better understand the technical content of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, different technical features in this application can be combined with each other.

[0026] Figure 1 This is a circuit block diagram illustrating the integrated high-voltage triggering and pre-ignition maintenance circuit for a xenon lamp, as provided in an embodiment of this application. Figure 1As shown, the integrated circuit for high-voltage triggering and pre-ignition maintenance of the xenon lamp includes a high-frequency drive unit, a high-frequency power conversion unit, an LCC resonant conversion unit, a high-voltage triggering branch, a pre-ignition maintenance branch, and a state sampling and control unit.

[0027] The high-frequency drive unit, high-frequency power conversion unit, LCC resonant conversion unit, high-voltage triggering branch, pre-ignition sustaining branch, and state sampling and control unit form a closed-loop working link in the order of "drive signal generation - input power high-frequency conversion - resonant energy transmission - high-voltage triggering or pre-ignition sustaining - state sampling - drive adjustment".

[0028] The high-frequency drive unit generates high-frequency drive signals and receives drive adjustment commands output by the state sampling and control unit. These drive adjustment commands can at least be used to adjust the enable state, pulse width, or soft-start process of the high-frequency drive signals. The specific circuitry of the high-frequency drive unit and the formation process of the two drive signals are further explained in conjunction with Figures 5(a) and 5(b).

[0029] The high-frequency power conversion unit is connected to the high-frequency drive unit. Figure 1 In the illustrated embodiment, the high-frequency power conversion unit includes a DC input terminal and a bus capacitor. Power switching devices connected in series between the positive and negative terminals of the DC input. , and respectively with power switching devices , Corresponding freewheeling diode , High-frequency drive signals enable power switching devices. , The circuit alternately conducts according to a set timing sequence, thereby converting the input DC power into high-frequency power. Figure 4 The power switching devices V12 and V13 shown are an actual circuit implementation of the above-mentioned high-frequency power conversion unit.

[0030] The LCC resonant converter unit is connected to the high-frequency power conversion unit, including a resonant network and a high-frequency transformer. . Figure 1 In the middle, series resonant capacitor and series resonant inductor Connected in series at the midpoint of the half-bridge to the high-frequency transformer A resonant capacitor is connected in parallel between the input terminals. With high frequency transformer The input terminals are connected accordingly. The high-frequency electrical energy output from the high-frequency power conversion unit passes through the resonant network to form a resonant current and resonant voltage adapted to the predetermined operating frequency and load impedance, and then passes through the high-frequency transformer. Transmitted to the output side.

[0031] Both the high-voltage triggering branch and the pre-combustion sustaining branch are coupled to the same high-frequency transformer. The output side is connected to the xenon lamp. The high-voltage triggering branch includes a multi-stage diode-capacitor voltage multiplier structure and a high-resistance network, used to progressively increase the output voltage and provide trigger voltage to the xenon lamp when it is in a high-resistance state before breakdown. The pre-ignition sustaining branch includes a rectifier circuit and an output filter energy storage element, used to rectify and filter the power output from the high-frequency transformer after the xenon lamp breaks down, and to provide pre-ignition sustaining power to the xenon lamp.

[0032] The status sampling and control unit is connected to both the xenon lamp and the high-frequency drive unit. The system acquires xenon lamp voltage and current sampling information, and determines the xenon lamp's operating state based on this information: not broken down, pre-ignition established, pre-ignition completed, or pre-ignition failed. It then generates a drive adjustment command based on the determined xenon lamp operating state. This drive adjustment command is returned to the high-frequency drive unit, which changes the high-frequency drive signal, thereby adjusting the high-frequency power output from the high-frequency power conversion unit and the power transmitted via the same high-frequency transformer to the high-voltage trigger branch and the pre-ignition sustaining branch.

[0033] Figure 1 The load current closed loop is directly illustrated: the xenon lamp current sampling information is obtained by sampling the load current. ,Will With a given current The current deviation signal is obtained by comparison. The current deviation signal is processed sequentially by the IC chip, the driver circuit, and the PWM circuit to form a control power switching device. , The high-frequency drive signal. Xenon lamp voltage sampling information can be obtained from... Figure 4 The output sampling branch shown is used to obtain voltage and current data, and the feedback process of the determination result to the high-frequency drive unit is combined. Figure 7 and Figure 8 Further explanation. Therefore, Figure 1 The current closed loop shown is Figure 4 , Figure 7 and Figure 8 The voltage sampling and state control shown together constitute the state sampling and control unit.

[0034] During startup, the xenon lamp is in a high-impedance state. The high-frequency electrical energy generated by the high-frequency power conversion unit is transmitted to the high-voltage trigger branch via the LCC resonant converter and the high-frequency transformer, and the multi-stage diodes... The capacitor multiplier structure generates a trigger voltage, causing the xenon lamp to break down. In this application, no relay or contactor-type active switching device is installed between the high-voltage triggering branch and the pre-ignition sustaining branch; the switching of the operating states of the two branches mainly relies on the change in the xenon lamp's own load impedance and... Figure 4The high-voltage isolation diode D14 in the circuit naturally achieves the following: After the xenon lamp breaks down, its equivalent impedance changes from a high-resistance state to a low-resistance state. The pre-ignition sustaining branch rectifies and filters the power output from the high-frequency transformer, establishing the pre-ignition sustaining voltage and current. The high-voltage isolation diode D14 acts as a unidirectional isolation diode, preventing the high voltage of the high-voltage triggering branch from reverse coupling to the pre-ignition sustaining main circuit, and also preventing the output of the pre-ignition sustaining branch from reverse charging the voltage doubler capacitor of the high-voltage triggering branch. The state sampling and control unit uses the acquired xenon lamp voltage and current sampling information to generate new drive adjustment commands, ensuring that the pre-ignition sustaining power reaches the corresponding state requirements.

[0035] in, Figures 6 to 8 The isolation control unit, relay J1, and AC contactor in the circuit do not participate in the branch switching from "high voltage triggering to pre-ignition maintenance". These devices are control devices for the subsequent power discharge circuit. The control conditions are as follows: after the status sampling and control unit determines that the xenon lamp pre-ignition is complete, the output circuit connection command is sent, which drives relay J1 and AC contactor to close via the isolation control unit, connecting the subsequent pulse discharge power circuit of the xenon lamp. If the pre-ignition timeout or pre-ignition failure occurs, the subsequent power circuit is kept disconnected to avoid the subsequent high voltage power circuit being mistakenly connected to the xenon lamp when pre-ignition has not been established.

[0036] With the above structure, high-voltage triggering and pre-ignition maintenance share the same high-frequency drive unit, high-frequency power conversion unit, LCC resonant conversion unit and high-frequency transformer. The load state change caused by xenon lamp breakdown directly becomes the output of the pre-ignition maintenance branch and the input for feedback adjustment by the state sampling and control unit, thereby enabling continuous connection between high-voltage triggering, pre-ignition maintenance and closed-loop control.

[0037] Combination Figure 1 The output side of the high-frequency transformer forms a first energy transmission path and a second energy transmission path. The first and second energy transmission paths are used to distinguish the transmission relationship of the high-frequency transformer output power to different functional branches, and do not require that the two functional branches have independent front-end power conversion circuits.

[0038] The first energy transmission path connects the high-frequency transformer and the high-voltage trigger branch. Its input is the high-frequency electrical energy from the output side of the high-frequency transformer. The process involves transmitting the high-frequency electrical energy to a multi-stage diode-capacitor voltage multiplier structure. Its output is the trigger voltage formed after stage-by-stage rectification, energy storage, and voltage superposition. The trigger voltage is applied to the xenon lamp via a high-voltage isolation diode and corresponding connection nodes.

[0039] The second energy transmission path connects the high-frequency transformer and the pre-ignition sustaining branch. Its input is also high-frequency electrical energy from the output side of the high-frequency transformer. The process involves transmitting this high-frequency electrical energy to the rectifier circuit and output filter energy storage element of the pre-ignition sustaining branch. Its output is the pre-ignition sustaining electrical energy applied to the xenon lamp. This pre-ignition sustaining electrical energy includes the pre-ignition sustaining voltage and pre-ignition sustaining current required for xenon lamp pre-ignition.

[0040] exist Figure 1 In the illustrated embodiment, two energy transmission paths are formed by two independent secondary windings on the output side of the same high-frequency transformer: the first energy transmission path is taken from the first secondary winding (trigger winding) of the high-frequency transformer, transmitting trigger energy to the high-voltage trigger branch; the second energy transmission path is taken from the second secondary winding (pre-ignition sustaining winding) of the high-frequency transformer, transmitting pre-ignition sustaining energy to the pre-ignition sustaining branch. The first and second secondary windings share the primary winding and core of the high-frequency transformer. The first and second energy transmission paths share the primary power conversion link of the high-frequency transformer and respectively undertake the transmission of trigger energy and pre-ignition sustaining energy; the output terminals of the high-voltage trigger branch and the pre-ignition sustaining branch are respectively connected to the xenon lamp, so that the breakdown result of the xenon lamp can serve as the load condition for switching the operating states of the two paths.

[0041] This two-path structure arranges the voltage doubler triggering function and the rectification pre-ignition sustaining function on the output side of the same high-frequency transformer, which can reduce the redundant power conversion devices and shorten the establishment link of pre-ignition sustaining power after triggering, thus providing a structural basis for integration and miniaturization.

[0042] like Figure 2 and Figure 3 As shown, the multi-stage diode-capacitor voltage multiplier structure in the high-voltage trigger branch includes multiple cascaded boost units, each of which includes a diode and a capacitor. The AC or pulsating electrical energy transmitted through the first energy transmission path charges the capacitor via the corresponding diode in one polarity stage, and in the other polarity stage, it is superimposed with the stored capacitor voltage to charge the next stage capacitor. Thus, rectification, energy storage, and voltage superposition are sequentially completed along each boost unit.

[0043] Figure 2 This illustrates the basic connection method of a multi-stage diode-capacitor stack. Diode to The capacitors are staggered along the upper and lower branches. to Connected between adjacent voltage multiplier nodes; as marked in the diagram. and This indicates the voltage relationship formed at the corresponding nodes during the charging and superposition process. A high-resistance resistor is connected to the output terminal. , and capacitors , This forms a high-resistivity network. Figure 3 This is a circuit board implementation of the above principle topology, where HV+ and GND constitute the input connection terminals, and the capacitor... to With diode to Forming a cascaded boost circuit, output side resistor , With capacitor , A high-impedance output network is formed, and the trigger voltage is output from the HVOUT terminal.

[0044] The parameter configuration inputs for the multi-stage diode-capacitor voltage multiplier structure include the minimum trigger voltage of the xenon lamp, the input voltage of the first energy transfer path, the trigger load current, the high-frequency drive frequency, and the allowable voltage ripple. Based on the above inputs, the number of boost unit stages, the capacitance value and withstand voltage of each capacitor, the reverse withstand voltage of each diode, and the high-impedance network parameters are determined to obtain the high-voltage trigger branch parameters that can output the trigger voltage under trigger load conditions.

[0045] Let the number of voltage multiplier stages be... The peak AC voltage input to the voltage multiplier structure via the first energy transmission path is Under ideal conditions where device voltage drop and leakage current are ignored, the maximum output voltage of the voltage multiplier structure is... It can be represented as: ;in, This represents the maximum output voltage under ideal conditions; Indicates the voltage multiplier stage; This indicates the peak AC voltage entering the voltage multiplier structure.

[0046] The capacitance values ​​of each capacitor are all Trigger load current is High-frequency drive frequency is In this case, the equivalent voltage drop caused by the load can be reduced. The estimate is: Therefore, considering the trigger load, the output voltage of the voltage doubler structure... According to the formula Verification.

[0047] Allowable voltage ripple is denoted as The output voltage ripple of the voltage multiplier structure can be calculated using the formula... When estimating the capacitance value of each capacitor based on the allowable voltage ripple, the following method can be used: ;in, Indicates the trigger load current; Indicates the high-frequency drive frequency; This indicates the capacitance value of the capacitor in each boost unit; This represents the equivalent voltage drop caused by the trigger load; This indicates the output voltage under the condition of triggering the load; This indicates the allowable voltage ripple. The above relationship is used to determine... and Then, the device voltage drop, leakage current, parameter deviation, and engineering margin are checked: ;in, This represents the minimum trigger voltage of the xenon lamp. The number of voltage multiplier stages, capacitor parameters, and device withstand voltages that meet this condition together constitute the configuration result of a multi-stage diode-capacitor voltage multiplier structure, which is used to build... Figure 2 or Figure 3 The high-voltage triggering branch is shown.

[0048] The above formulas for calculating voltage drop, output voltage, output ripple, and capacitance are applicable to... Figure 2 , Figure 3 Walton (Cockcroft) Walton multistage diode Capacitor voltage multiplier topology; where the voltage multiplier stage N refers to the number of cascaded boost units in the topology; the input waveform is the high-frequency AC voltage output from the high-frequency transformer; the applicable load condition is a small-current resistive load during the xenon lamp triggering stage, and it is assumed that the capacitance value of all boost units is equal, all being C. This set of formulas is the classical theoretical estimation formula for the Walton voltage multiplier topology. This application uses a PLECS simulation model (corresponding to...) Figure 9 High-voltage trigger simulation waveform), hardware prototype trigger experiment test (corresponding to) Figure 11 (High-voltage triggering test waveform) verifies the engineering applicability of this set of formulas under the current application conditions.

[0049] In this embodiment, the high-resistance network is composed of multiple high-resistance resistors connected in series, and is connected in series with a multi-stage diode. The capacitor multiplier structure is connected to the xenon lamp at its output terminal. The terms "adaptive voltage divider resistor" and "high-resistance voltage divider absorption" are descriptive terms describing the function of this high-resistance network, and do not refer to an adaptive adjustable resistor whose resistance can be actively and dynamically adjusted. This high-resistance network performs two functions simultaneously: first, it adjusts the actual trigger voltage applied to the xenon lamp through voltage division; second, after the xenon lamp breaks down, it provides a discharge and absorption path for the voltage multiplier capacitor and the residual high-voltage charge at the output node.

[0050] In one specific embodiment, the total resistance of the high-resistance network is greater than 2MΩ; this total resistance is significantly greater than the equivalent resistance after the xenon lamp breaks down, thereby reducing the current shunting caused by the high-resistance network to the second energy transmission path during the pre-combustion sustaining phase. The total resistance of the high-resistance network and the power rating of the resistive devices are configured according to the trigger voltage, allowable discharge current, and target discharge time.

[0051] This application uses the Cockcroft high-voltage triggering branch. Walton voltage multiplier topology, in this application, the voltage multiplier stage N is defined as the number of cascaded boost units, each boost unit includes 1 diode and 1 voltage multiplier energy storage capacitor; the N-stage voltage multiplier stack link contains N boost diodes and N voltage multiplier energy storage capacitors, and the peripheral isolation diodes of the branch are not included in the boost unit inside the voltage multiplier stack. Figure 2 and Figure 3 The circuit principle and circuit board implementation example of a 5-stage boost unit are shown. The boost diodes inside the voltage multiplier stack are D1~D5, a total of 5 boost diodes, and there are 5 voltage multiplier energy storage capacitors. This topology is the actual circuit used in the physical hardware prototype of this application. In this five-stage voltage multiplier structure, D1 to D6 are provided; where D1... D5 is the internal boost unit diode of the voltage multiplier stack, and D6 is the external isolation diode of the high-voltage trigger branch, which does not belong to the internal boost unit of the voltage multiplier stack. Figure 9 The simulation model shown adopts a voltage multiplier topology with a five-stage boost unit. It is a special working condition for simulation verification and is only used to verify the theoretical calculation formula of voltage multiplier. It is not equivalent to a physical hardware prototype. Figure 2 , Figure 3 Physical prototype topology and Figure 9 The simulation models belong to different implementation / verification conditions, but the diodes The core operating principles of capacitor-based rectification, energy storage, and voltage superposition remain consistent; regardless of simulation or physical implementation, the number of voltage multiplier stages is determined based on the minimum trigger voltage of the xenon lamp and the input parameters of the first energy transfer path.

[0052] With the above structure and parameter configuration, the high-frequency electrical energy input through the first energy transmission path is converted into a trigger voltage that is not lower than the minimum trigger voltage of the xenon lamp. The high-resistance network further processes the residual charge after breakdown, thereby improving the trigger success rate while reducing the impact of residual high voltage on the pre-combustion sustaining branch and subsequent power circuit.

[0053] like Figure 4 As shown, the input terminal of the pre-ignition sustaining main circuit is connected. AC power supply. The AC input passes sequentially through a negative temperature coefficient thermistor (NTC) and a common-mode inductor. , A two-stage composite EMI filter circuit consisting of capacitors CK1 and CK2 is then input to the rectifier bridge. The common-mode inductor is used to suppress common-mode interference, and the capacitors are used to filter out series-mode interference. The output of the rectifier bridge is connected to a resistor... , and bus capacitor , The DC bus is formed to supply power to the high-frequency power conversion unit composed of power switching devices V12 and V13.

[0054] The gates of power switching devices V12 and V13 receive G-Q1 and G-Q2 respectively, and they alternately conduct according to a set phase relationship and dead time. The output of the high-frequency power conversion unit is connected to the input of the high-frequency transformer via a series resonant inductor and a series resonant capacitor, and a parallel resonant capacitor is connected to the input of the high-frequency transformer, thus forming an LCC resonant network. This connection relationship is related to... Figure 1 In , , and high frequency transformers Correspondingly.

[0055] The second energy transfer path transfers the electrical energy output from the high-frequency transformer to the pre-combustion sustaining branch. The pre-combustion sustaining branch includes... Figure 4 The diagram shows the secondary-side rectifier network and the output filter and energy storage element. The secondary-side rectifier network rectifies high-frequency power, and the output filter and energy storage element filters and stores the rectified result, forming a pre-ignition sustaining voltage between the load terminals V1 and V2, and providing a pre-ignition sustaining current to the xenon lamp. The high-voltage side output node HV+ is connected to the corresponding output node via diode D14 to limit the reverse coupling of the trigger voltage generated by the high-voltage trigger branch to the pre-ignition sustaining main circuit.

[0056] Figure 4 Resistor on the right , , This forms a sampling branch, from which the Sample+ signal is derived; the output capacitor is used to filter the sampling node and the load node. The sampled signal obtained by Sample+ and the current sampled signal in the load circuit are jointly provided to the state sampling and control unit. The relay control terminal is derived from Relay+ and Relay-, where Relay+ and... Figure 8 The AC contactor shown controls the relay connection.

[0057] Figure 4 The energy and information transmission relationship shown is as follows: AC input is filtered and rectified by EMI to form DC bus power; DC bus power is converted into high-frequency power by high-frequency power conversion unit; high-frequency power is transmitted to the second energy transmission path through LCC resonant network and high-frequency transformer; the pre-combustion sustaining branch is rectified and filtered to obtain pre-combustion sustaining power; the voltage and current formed at the load end are sampled and used as input for subsequent state determination and drive adjustment.

[0058] Therefore, the LCC resonant network can establish a controlled resonant energy transfer relationship between the high-frequency power conversion unit and the high-frequency transformer. The pre-ignition sustaining branch converts the transfer result into a pre-ignition sustaining voltage and pre-ignition sustaining current that can be used by the xenon lamp, thereby providing continuous energy for stable pre-ignition after the xenon lamp breaks down.

[0059] The inputs for LCC resonant parameter configuration include the input voltage range of the high-frequency power conversion unit, the target voltage for xenon lamp pre-ignition, the target current for xenon lamp pre-ignition, and the dynamic resistance characteristics during the xenon lamp pre-ignition stage. The dynamic resistance during the xenon lamp pre-ignition stage is denoted as... Its value varies with pre-ignition time, sustaining voltage, and sustaining current. During design, the high-frequency transformer ratio is first determined based on the input voltage range and the target pre-ignition voltage of the xenon lamp. Then, based on the target voltage, target current, and... The series resonant inductor, series resonant capacitor, and parallel resonant capacitor are determined, and finally the switching frequency of the high-frequency drive unit is configured based on the obtained resonant frequency.

[0060] Let the turns ratio of the high-frequency transformer be... The minimum input voltage of the high-frequency power conversion unit is The target voltage for xenon lamp pre-ignition is The voltage drop of the secondary rectifier device is The maximum voltage gain of the LCC resonant converter unit is The turns ratio of a high-frequency transformer can be calculated using the formula... Perform initial configuration; among which, This indicates the turns ratio of the high-frequency transformer used to match the input voltage with the target voltage for xenon lamp pre-ignition. Indicates the minimum input voltage within the input voltage range; Indicates the target voltage for xenon lamp pre-ignition; This indicates the voltage drop across the secondary rectifier device; This represents the maximum voltage gain of the LCC resonant converter unit. During design, a margin can be reserved for the maximum voltage gain to accommodate input voltage fluctuations and device parameter deviations.

[0061] The series resonant inductor is denoted as The series resonant capacitor is denoted as The parallel resonant capacitor is denoted as .Depend on and Determined series resonant frequency for: First determine the series resonant inductor. Series resonant frequency with the target At that time, series resonant capacitor You can follow the formula Sure.

[0062] Let the capacitance ratio be In this application, the capacitance ratio m is defined as the ratio of the parallel resonant capacitor to the series resonant capacitor. Therefore, the parallel resonant capacitor... It can be represented as: ;in, Indicates the series resonant frequency; Indicates a series resonant inductor; Indicates a series resonant capacitor; Indicates a parallel resonant capacitor; This represents the capacitance ratio between the parallel resonant capacitor and the series resonant capacitor. In a specific embodiment of this application, considering the dynamic resistance characteristics during the xenon lamp pre-ignition stage, and after joint frequency sweep simulation verification, m=1 is actually selected, i.e. .

[0063] To adapt the LCC resonant network to the dynamic resistance characteristics during the xenon lamp pre-combustion stage, the fundamental frequency approximation (FHA) method can be used to convert the dynamic resistance of the xenon lamp to the input side of the high-frequency transformer. In this application, the high-frequency transformer turns ratio... Defined as the ratio of the number of turns on the primary side to the number of turns on the secondary side of a high-frequency transformer, i.e. The equivalent load impedance referred to the primary side of the high-frequency transformer is denoted as Zin(t). Therefore, the equivalent load impedance... It can be represented as: .

[0064] In a specific embodiment of this application, the ratio of the number of turns on the primary and secondary sides of the high-frequency transformer in the pre-ignition sustaining path is... That is, the turns ratio is 0.5. Substituting this into the above formula, we obtain the equivalent load impedance after conversion. The conversion formula and the hardware transformation ratio parameters are self-consistent.

[0065] Furthermore, the total input equivalent impedance Zeq can be determined based on the structure of the LCC resonant network and the calculated dynamic load; the total input equivalent impedance is determined by the loop angular frequency ω, the series resonant inductance Lr, the parallel resonant capacitor Cp, and the xenon lamp dynamic resistance Rpre(t).

[0066] according to The range of variation, for , , and switching frequency Perform joint frequency sweeping or simulation verification to ensure that the LCC resonant network forms a signal with the target operating frequency band. The resonant circuit impedance is matched accordingly, and the output pre-ignition sustaining voltage and pre-ignition sustaining current cover the xenon lamp pre-ignition target voltage and xenon lamp pre-ignition target current. The output of the joint verification is the combined configuration result of the high-frequency transformer turns ratio, resonant element parameters, and switching frequency. This result is used for... Figure 4The circuits shown in Figure 5(a) and Figure 5(b) are as follows.

[0067] In one specific embodiment, the input power supply is The rectified DC bus voltage is approximately Series resonant inductor Pick Series resonant capacitor Pick Parallel resonant capacitor Pick The actual allowable tolerance range for capacitor components is ±0.5nF. Pre-ignition high-frequency drive switching frequency. Pick The high-frequency transformer turns ratio corresponding to the pre-combustion sustaining path is adopted. The design value. According to... and The calculated series resonant frequency is approximately .

[0068] The above parameter configuration allows the input voltage range, xenon lamp pre-ignition target voltage, target current, and dynamic resistance characteristics to jointly constrain the LCC resonant network and high-frequency transformer. The resulting resonant parameters are then used to determine the switching frequency of the high-frequency drive unit, which can reduce the output mismatch caused by the independent configuration of resonant parameters, load characteristics, and drive frequency.

[0069] As shown in Figures 5(a) and 5(b), the high-frequency drive unit includes a pulse width modulation controller, an isolation drive circuit, and a gate drive network. The pulse width modulation controller uses an SG3525, the isolation drive circuit includes IC2 and IC3 corresponding to the two drive channels respectively, and the gate drive network includes resistors, overvoltage suppression devices, fast discharge devices, and decoupling filter elements disposed between the two isolation drive output terminals and the corresponding power switching devices.

[0070] The SG3525 generates a first pulse width modulation (PWM) signal and a second PWM signal according to the drive adjustment command. OUTA and OUTB in Figure 5(a) output two signals with preset phase relationships and dead times, respectively, which are then converted into Q1PWM and Q2PWM signals via corresponding resistor networks. The first and second PWM signals serve as inputs to the isolated drive circuit.

[0071] Q1PWM input isolation driver chip IC2, Q2PWM input isolation driver chip IC3. In the illustrated embodiment, IC2 and IC3 use the 1ED3123MC12HXUMA1 isolation driver chip. The low-voltage control side of both chips is controlled by... The power supply is connected to GND_D; the high-voltage drive side is powered by the corresponding isolated drive power supply. IC2 performs electrical isolation and drive enhancement on the first pulse width modulation signal to obtain the first isolated drive signal; IC3 performs electrical isolation and drive enhancement on the second pulse width modulation signal to obtain the second isolated drive signal. The positive drive power supply on the high-voltage drive side of the isolated drive circuit is +15V, marked as +15V_Q1 / +15V_Q2 in Figure 5(b); the negative drive power supply is -3V, marked as... 3V_Q1 / 3V_Q2.

[0072] The first isolation drive signal is processed by the first gate drive network to form the first gate drive signal G-Q1, and the second isolation drive signal is processed by the second gate drive network to form the second gate drive signal G-Q2. G-Q1 and G-Q2 are respectively provided to... Figure 4 The power switching devices V12 and V13 in the circuit convert the low-voltage control output of the pulse width modulation controller into two gate drive inputs of the high-frequency power conversion unit.

[0073] Therefore, Figure 5(a), Figure 5(b) and Figure 4 A clear signal transmission relationship is established: the drive adjustment command enters the SG3525; the SG3525 outputs the first and second pulse width modulation signals; IC2 and IC3 output the first and second isolation drive signals respectively; the two gate drive networks output G-Q1 and G-Q2 respectively; G-Q1 and G-Q2 control V12 and V13 to complete the high-frequency conversion of the input power. Two-channel isolation and drive enhancement improve the electrical isolation between the low-voltage control side and the power side, and provide gate drive signals with amplitude and drive capability adapted to the high-frequency power switching devices.

[0074] Referring again to Figure 5(a), the SYNC pin of the SG3525 is used for synchronization, the SOFT_START pin for soft start, and the SHUTDOWN pin for shutdown. During pre-ignition startup, the pulse width modulation controller gradually adjusts the pulse widths of the first and second pulse width modulation signals according to the soft start sequence, so that the high-frequency power output of the high-frequency power conversion unit is gradually established, thereby preventing abrupt changes in the output of the pre-ignition sustaining branch. After the state sampling and control unit generates a new drive adjustment command, the pulse width modulation controller continues to update the two pulse width modulation signals according to the command.

[0075] Let the timing resistor of SG3525 be... The timing capacitor is Discharge resistance is Its switching frequency You can follow the formula Perform initial configuration; assume the voltage at the compensation terminal of the error amplifier is... The reference voltage is The duty cycle control quantity corresponding to the pulse width The configuration can be based on the controller's error amplification output. In a specific implementation, the following relationship is used for initial debugging: ;in, Indicates the switching frequency of the high-frequency drive unit; Indicates the timing resistor; Indicates the timing capacitor; Indicates the discharge resistance; This represents the duty cycle control value corresponding to the pulse width; This indicates the voltage at the compensation terminal of the error amplifier; This represents the reference voltage. By configuring the switching frequency using an external timing element and changing the control quantity at the compensation terminal according to the drive adjustment command, the switching frequency configuration result and the pulse width adjustment result can be obtained respectively.

[0076] The gate drive network includes a gate damping branch, a gate overvoltage suppression branch, and a gate charge release branch. In Figure 5(b), resistors R10, R12, R14, and R16 at the output of IC2 constitute the first gate damping branch, and resistors R11, R13, R15, and R17 at the output of IC3 constitute the second gate damping branch; the resistance values ​​of each resistor in the illustrated embodiment are... It is used to share the drive pulse current, suppress gate oscillation, and regulate the turn-on and turn-off edges.

[0077] In Figure 5(b), D11 and D12 form the gate overvoltage suppression branch of the corresponding drive channel, used to limit the gate drive voltage; D14 and D15 form the gate charge release branch of the corresponding drive channel, used to provide a fast release path for the gate charge during the turn-off process of the power switching device. C11, C12, C20, C21 and C13, C14, C23, C24 are respectively set on the power supply side of the two isolated drive channels, and C15 and C16 are set on the low-voltage control side for decoupling and filtering.

[0078] Let the positive output voltage of the isolated drive power supply be... The negative output voltage is The gate-source drive voltage of the power switching device for:

[0079] Let the gate current limiting equivalent resistance be... The maximum allowable gate-source drive voltage is Then the maximum gate drive current It can be estimated as follows:

[0080] In the formula, and These represent the positive and negative output voltages of the isolated drive power supply, respectively. Indicates the gate-source drive voltage; This represents the gate current limiting equivalent resistance; Indicates the maximum allowable gate-source drive voltage; This indicates the maximum gate drive current. The drive power rails are checked against the gate ratings and gate charge of the power switching device. Then, the gate drive network parameters are obtained.

[0081] By controlling the build-up speed of high-frequency power through soft-start timing, and by using gate damping, overvoltage suppression, and charge release branches to jointly process the two isolated drive signals, the drive stability of the high-frequency power conversion unit can be improved while avoiding bridge arm shoot-through and gate overvoltage, and reducing gate oscillation and turn-off tail.

[0082] like Figure 6 As shown, an isolation control unit is set between the state sampling and control unit and the subsequent power circuit. Figure 6 The pre-ionization signal input channel, isolation optocoupler, IC driver chip, PWM channel, upper rectification and DC / DC conversion channel, voltage multiplier circuit, and high-voltage isolation diode DHV constitute the trigger control link; the lower rectification and DC / DC conversion channel, AC contactor, and the circuit containing the xenon lamp load constitute the isolated and controlled downstream power circuit. In this application, the high-voltage trigger branch and pre-ignition maintenance branch maintain electrical connection with the xenon lamp throughout the entire operation; the AC contactor is not used to isolate the ultra-high voltage area of ​​the trigger control link, but is connected in series between the xenon lamp and the downstream pulse discharge power circuit, only realizing the on / off control of the downstream power circuit. The contactor contact working states are as follows: during the triggering stage, before pre-ignition is established, the contactor contact remains open, and the downstream power circuit is disconnected from the xenon lamp; when pre-ignition is completed and a circuit connection command is received, the contactor contact closes, connecting the downstream pulse discharge power circuit to the xenon lamp; when pre-ignition timeout or pre-ignition failure occurs, the contactor contact remains open, and the downstream power circuit remains disconnected from the xenon lamp to prevent malfunction of the downstream power circuit.

[0083] The status sampling and control unit obtains xenon lamp voltage and current sampling information through a sampling resistor, an output sampling branch, and an isolation optocoupler, and outputs circuit control commands to the AC contactor via an isolation relay. The status sampling and control unit keeps the AC contactor open until it obtains pre-ignition completion information and meets the subsequent connection conditions; only then does it connect the downstream power circuit via the isolation control unit. Figure 6 The structure shown is thus Figure 7 State determination and Figure 8 The feedback control in the system provides the hardware connectivity foundation.

[0084] like Figure 7 As shown, the state sampling and control unit first acquires the pre-ignition start command, and then acquires the operating status of the power supply unit and the energy storage circuit. The operating status of the power supply unit is used to characterize whether the high-frequency drive unit, control power supply, and related power supply circuits meet the operating conditions, while the energy storage circuit status is used to characterize whether the subsequent energy storage and power circuits are in a state that allows pre-ignition start. The state sampling and control unit detects the above states and obtains a judgment result on whether the pre-ignition start conditions are met.

[0085] When the pre-ignition start-up conditions are met, the state sampling and control unit generates an initial drive adjustment command. This command causes the high-frequency drive unit to activate the xenon lamp pre-ionization signal and applies a trigger voltage to the xenon lamp through the high-frequency power conversion unit and the high-voltage trigger branch. After the xenon lamp is broken down, the high-frequency drive unit performs a pre-ignition soft start, causing the pulse widths of the two pulse width modulation signals to gradually change according to the soft start sequence, thereby establishing pre-ignition sustaining power.

[0086] After the pre-combustion sustains the electrical energy, the status sampling and control unit acquires xenon lamp voltage sampling information and xenon lamp current sampling information. Figure 7 The "sampled output current" directly plotted in the image corresponds to the xenon lamp current sampling information; the xenon lamp voltage sampling information is obtained from... Figure 4 The output sampling branch shown is used to obtain the results. The two types of sampling information are compared with the corresponding state judgment thresholds to obtain the pre-ignition completion judgment result, and the working state of the xenon lamp is determined accordingly.

[0087] In one specific embodiment, the determination of pre-ignition completion requires the simultaneous fulfillment of two conditions: xenon lamp voltage and xenon lamp current, which are logically ANDed. The voltage and current sampling signals do not directly use the original instantaneous sampled values, nor do they use the effective values. Instead, they are filtered average values ​​obtained after hardware RC filtering and software moving average processing. Furthermore, these conditions need to be maintained continuously for a preset duration before pre-ignition completion can be determined. In this embodiment, the continuous determination duration is set to be greater than 50ms to suppress sampling noise and spike interference, avoiding false judgments.

[0088] This application divides the operation of a xenon lamp into four states: no breakdown, pre-ignition establishment, pre-ignition completion, and pre-ignition failure. The conditions for determining each state are as follows: (1) Non-breakdown state: The xenon lamp maintains high resistance, the filtered xenon lamp voltage is at a high level, and the pre-ignition maintenance current is close to zero; (2) Pre-ignition establishment state: The xenon lamp has been broken down. After filtering, the xenon lamp voltage begins to drop and the xenon lamp current increases, but the voltage and current thresholds corresponding to the completion of pre-ignition have not yet been reached at the same time. (3) Pre-ignition completion status: When the filtered average value meets the condition that the xenon lamp current sampling value is greater than 1A and the xenon lamp voltage sampling value is less than 200V, and the above conditions are maintained continuously for a preset time, the pre-ignition is determined to be completed and the pre-ignition completion information is generated; if any condition is not met, the pre-ignition is not determined to be completed. (4) Pre-ignition failure status: Pre-ignition timer starts from the start of pre-ignition. If the pre-ignition duration reaches the preset timeout time and the pre-ignition completion judgment condition is not met throughout the entire process, the pre-ignition is judged to have failed.

[0089] When the pre-ignition completion determination result is incomplete, the status sampling and control unit calculates the deviation between the xenon lamp voltage sampling information, xenon lamp current sampling information and the corresponding status determination threshold, and generates an updated drive adjustment command according to the preset adjustment relationship. Two different working stages need to be distinguished: the initial stage of pre-ignition startup is a soft-start open-loop stage, in which the pulse width gradually increases the duty cycle to achieve a smooth build-up of output energy; after the soft start, it enters the closed-loop feedback adjustment stage, where the pulse width is no longer uniformly reduced, but rather differentiated adjustment is performed based on the actual deviation direction of voltage and current: if the current maintained after xenon lamp filtering is lower than the current threshold, indicating insufficient output energy, the drive pulse width is increased to enhance the electrical energy transmitted to the xenon lamp; if the xenon lamp voltage remains higher than the voltage threshold and the current does not increase significantly, the pulse width is adjusted appropriately according to the deviation; if abnormal risks such as current over-limit are detected, pulse width reduction protection is implemented. Figure 7 The specific process shown adopts an adjustment branch of "reducing the signal pulse width - re-pre-ignition - re-judgment", and the sampling information obtained again is used as the input for the next pre-ignition completion judgment.

[0090] When the pre-ignition completion determination result is "complete," the status sampling and control unit generates pre-ignition completion information, which is then used for... Figure 6 and Figure 8 The isolation control unit and subsequent power loop control are shown. If pre-ignition is not completed after multiple adjustments, the status sampling and control unit generates a pre-ignition failure message and stops the current pre-ignition process.

[0091] The above control process first establishes the pre-ignition start-up conditions in the working state of the power supply unit and the state of the energy storage circuit, then establishes the trigger and pre-ignition output in the initial drive adjustment command, and then forms the pre-ignition completion judgment result in the voltage and current sampling information. The judgment result further forms the updated drive adjustment command or pre-ignition completion information, so that each state data and processing result can be used continuously in the control flow.

[0092] The isolation control unit is connected to the status sampling and control unit, and controls the circuit according to the loop control command. Figure 6The on / off state of the downstream power circuit is shown. The pre-ignition completion information is the result of the pre-processing that changes the downstream power circuit from off to on; when the pre-ignition completion information is not generated or the pre-ignition failure information has been generated, the isolation control unit keeps the AC contactor and the downstream power circuit disconnected.

[0093] When the state sampling and control unit generates the initial drive adjustment command, it starts the pre-ignition timing to obtain the pre-ignition duration and compares it with the preset timeout time. If the pre-ignition completion information is generated before the pre-ignition duration reaches the preset timeout time, the state sampling and control unit generates a loop connection command after a preset delay time; the isolation control unit controls the AC contactor to operate according to the loop connection command, so that the downstream power loop is connected.

[0094] If the pre-ignition duration reaches the preset timeout period and pre-ignition completion information is not generated, the status sampling and control unit generates a pre-ignition stop command and updates the pre-ignition retry count. The pre-ignition stop command is used to stop the high-frequency drive unit to prevent the high-voltage trigger branch and the pre-ignition maintenance branch from continuously outputting. When the updated pre-ignition retry count does not reach the preset maximum retry count and the preset retry interval has been met, the status sampling and control unit generates a pre-ignition restart command and re-executes the pre-ignition start condition detection, initial drive, sampling, and judgment process. When the updated pre-ignition retry count reaches the preset maximum retry count, pre-ignition failure information and a loop disconnect command are generated to keep the downstream power loop disconnected.

[0095] In one specific embodiment, the preset timeout for a single pre-ignition window is 2 seconds; two independent counters are set: within a single 2-second window, a maximum of 3 pulse width adjustments are allowed without stopping the drive. After 3 adjustments, failure is not directly determined, and the window continues to wait for the timeout; when the 2-second timeout is reached, a termination command is sent to shut down the drive, and the retry count of the whole machine is incremented by one. The retry interval for each restart of pre-ignition is not less than 10ms, and the maximum number of retryes for the whole machine is set by the host computer.

[0096] If pre-ignition is completed within a 2-second window, the subsequent power circuit (discharge main circuit) is activated after a preset delay. Pre-ignition maintains continuous output until an external termination command is received, at which point the high-frequency drive is shut down. If the entire machine fails to complete pre-ignition after reaching the maximum number of retry attempts set by the host, a pre-ignition failure message is generated. The energy storage circuit is only allowed to start after at least one controlled circuit has completed pre-ignition. This embodiment is a single-channel controlled pre-ignition circuit, but this logic supports multi-channel circuit expansion. If all circuits have not completed pre-ignition, the subsequent power circuit remains disconnected even if an energy storage command is received.

[0097] like Figure 8As shown, the pre-ignition control feedback circuit includes a pre-ignition control circuit, a pre-ignition success feedback circuit, and an AC contactor control relay. The pre-ignition control circuit includes an optocoupler IC4, resistors R16 and R17, and capacitors C13 and C21. Sim+ is connected to the input side of IC4, and Driver+ is connected to the output side of IC4. When external control enables Sim+ to reach the active state, IC4 isolates and converts this state to the Driver+ drive enable state, causing the high-frequency drive unit to start emitting waves; when Sim+ is deactivated, Driver+ enters the stop drive state.

[0098] Sim+ (External pre-ignition start input signal): Default high level; valid state is low level (grounded), low level enables optocoupler IC4; Driver+ (optocoupler output, driver board enable signal): Default high level; low level when driver is enabled; Driver+ is pulled low when IC4 is turned on, and the high-frequency driver unit starts emitting waves; after Sim+ returns to high level, IC4 is turned off, Driver+ returns to high level, and the driver output stops. Relay+ (relay coil control signal): Default is low level; valid state is high level; when high level, the AC contactor controls the relay J1 coil to be energized and engaged. +12V_OUT (Relay contact output power): No output by default; after relay J1 is energized, it outputs +12V, which is used to enable optocoupler IC3 in the pre-ignition success feedback circuit. Sim_OK (Pre-ignition completion status feedback output): Default +12V high level; pre-ignition completion valid status is low level; after +12V_OUT is powered on, optocoupler IC3 is turned on, Sim_OK is pulled low, and pre-ignition completion is fed back to the main controller.

[0099] The AC contactor controls the relay using J1, with the coil terminals connected to Relay- and Relay+. After the status sampling and control unit generates a circuit connection command based on the pre-ignition completion information, Relay+ becomes active, relay J1 actuates, and a set of contacts outputs 220AC_OUT to control... Figure 6 The AC contactor in the circuit has another set of contacts that output +12V_OUT to enable the feedback circuit for successful pre-ignition.

[0100] The pre-ignition success feedback circuit includes optocoupler IC3, LED D11, resistors R12 and R15, and capacitors C17, C18, C19, and C22. +12V_OUT is applied to optocoupler IC3 via a corresponding branch, and optocoupler IC3 isolates and switches the pre-ignition completion status to the Sim_OK terminal. Figure 8 In the interface logic shown, Sim_OK has changed from the original The high level is converted to a low level, forming a pre-ignition completion message that is fed back to the controller or DSP microcontroller.

[0101] Figures 6 to 8 The information transfer relationship between them is as follows: Figure 7 Generate pre-ignition completion or pre-ignition failure information; pre-ignition completion information enables Relay+; relay J1 outputs 220AC_OUT and +12V_OUT; 220AC_OUT controls... Figure 6 The AC contactor in the circuit connects the subsequent power circuit; +12V_OUT enables the pre-ignition success feedback circuit and changes Sim_OK; Sim_OK feeds back the pre-ignition completion status to the status sampling and control unit. Pre-ignition failure information causes Driver+ to enter a stop-drive state and keeps the AC contactor open.

[0102] By controlling pre-ignition timing, delayed connection, stop drive, interval retry, maximum number of retryes, and isolation disconnection, it is possible to avoid the subsequent power circuit being mistakenly connected when pre-ignition is not completed, and to limit the stress caused by continuous triggering on the high-voltage branch and power switching devices.

[0103] This application also provides a structural and parameter design method for an integrated circuit for high-voltage triggering and pre-ignition maintenance of a xenon lamp, the method comprising the following steps: First, obtain the circuit design information. This information includes the input voltage range, minimum trigger voltage of the xenon lamp, target pre-ignition voltage, target pre-ignition current, dynamic resistance characteristics during the pre-ignition phase, high-frequency power conversion drive constraints, and xenon lamp status determination conditions. The input voltage range includes the design range of the AC input or the rectified DC bus voltage; the high-frequency power conversion drive constraints include the allowable switching frequency of the power switching devices, rated gate voltage, gate charge, dead time, and soft-start requirements; the xenon lamp status determination conditions include voltage and current thresholds, as well as pre-ignition timeout and retry conditions. This circuit design information serves as a common input for subsequent design processes.

[0104] Secondly, based on the minimum trigger voltage of the xenon lamp and the input parameters of the trigger branch, the voltage multiplication stage, capacitor parameters, and high-resistance network parameters of the multi-stage diode-capacitor voltage multiplier structure are determined, resulting in the high-voltage trigger branch design. The trigger branch input parameters include the input voltage of the first energy transfer path, the trigger load current, the high-frequency drive frequency, and the allowable voltage ripple. Candidate voltage multiplication stages and capacitor values ​​are calculated according to the aforementioned voltage multiplication relationship, and the reverse withstand voltage of the diodes, the withstand voltage of the capacitors, and the resistance and power rating of the high-resistance network are verified. The high-voltage trigger branch design results include at least the voltage multiplication stage, the device parameters of each boost unit, the high-resistance network parameters, and the output voltage verification results under trigger load conditions.

[0105] Next, based on the input voltage range, xenon lamp pre-ignition target voltage, xenon lamp pre-ignition target current, and dynamic resistance characteristics, the resonant parameters of the LCC resonant network, the turns ratio of the high-frequency transformer, and the rectification configuration of the pre-ignition sustaining branch are determined, resulting in the design outcome of the pre-ignition sustaining branch. Specifically, the high-frequency transformer turns ratio is first determined based on the input voltage range and xenon lamp pre-ignition target voltage, and then the turns ratio is determined based on the xenon lamp pre-ignition target voltage, target current, and dynamic resistance variation range. , , The design process involves determining the rectifier devices, output filter energy storage elements, and their withstand voltage, current-carrying capacity, and energy storage parameters based on the pre-ignition sustaining voltage and current. The pre-ignition sustaining branch design results include the high-frequency transformer turns ratio, LCC resonant parameters, pre-ignition sustaining branch rectifier configuration, and target operating frequency band.

[0106] Subsequently, based on the design results of the high-voltage trigger branch and the pre-ignition sustaining branch, a first energy transmission path and a second energy transmission path were determined on the output side of the same high-frequency transformer. The connection relationships between the high-voltage trigger branch, the pre-ignition sustaining branch, and the xenon lamp were also determined, resulting in an integrated output structure design. In this process, the input terminal of the voltage multiplier structure in the high-voltage trigger branch design was mapped to the first energy transmission path, and the input terminal of the rectifier circuit in the pre-ignition sustaining branch design was mapped to the second energy transmission path. The output terminals of both branches were then connected to the xenon lamp. The integrated output structure design includes at least the connection nodes on the output side of the high-frequency transformer, two energy transmission paths, two functional branches, and their connection relationships with the xenon lamp. The specific topology corresponds to… Figures 1 to 4 .

[0107] Then, based on the resonance parameters and high-frequency power conversion drive constraints, the switching control requirements of the high-frequency power conversion unit, the high-frequency drive parameters, and the drive relationship between the high-frequency drive signal and the high-frequency power conversion unit are determined, resulting in the drive conversion design. Specifically, based on... , The switching frequency is determined based on the operating frequency band of the complete LCC network. The isolation drive power rail, gate damping parameters, and drive current are determined according to the gate ratings and gate charges of the power switching devices. The phase relationship, dead time, and soft-start timing of the two pulse width modulation signals are determined based on the bridge arm structure. The first and second gate drive signals are then mapped to the corresponding power switching devices. The drive conversion design results include the high-frequency power conversion topology, switching frequency, two-path drive timing, isolation drive configuration, gate drive network parameters, and signal connection relationships. The specific circuits correspond to... Figure 4 And Figure 5.

[0108] Furthermore, based on the xenon lamp state determination conditions, xenon lamp voltage sampling parameters, xenon lamp current sampling parameters, and drive conversion design results, the feedback control relationship between the xenon lamp operating state and drive adjustment parameters is determined, resulting in the state feedback control design results. Specifically, the range, proportion, and filtering parameters of the voltage sampling branch and the current sampling branch are determined, and the two types of sampling information are associated with the corresponding state determination thresholds. Initial drive, deviation calculation, pulse width update, pre-ignition completion, timeout stop, interval retry, and subsequent power loop isolation logic are configured. The state feedback control design results include sampling parameters, state determination conditions, drive adjustment rules, pre-ignition completion feedback method, and subsequent power loop on / off rules, the specific implementation of which corresponds to... Figures 6 to 8 .

[0109] Finally, based on the design results of the high-voltage trigger branch, the pre-ignition sustaining branch, the integrated output structure, the drive conversion, and the state feedback control, the structure and parameters of the integrated circuit for xenon lamp high-voltage triggering and pre-ignition sustaining are configured, resulting in the integrated circuit design. In the specific configuration, the connection relationships between each unit and branch are first established according to the integrated output structure design results. Then, the device parameters of the high-voltage trigger branch, LCC resonant network, pre-ignition sustaining branch, and high-frequency drive unit are written. Subsequently, the sampling ratio, state judgment threshold, soft start, timeout, and retry parameters are written. The trigger voltage, pre-ignition sustaining voltage, pre-ignition sustaining current, and state feedback process are verified through simulation and experiments.

[0110] In the above design method, each step yields a clear result for subsequent use: the design results of the high-voltage trigger branch and the pre-ignition sustaining branch are used to form the integrated output structure design result; the resonant parameters in the pre-ignition sustaining branch design result are used to form the drive conversion design result; the drive conversion design result and the state determination conditions are used together to form the state feedback control design result; the five types of design results ultimately combine to form the integrated circuit design result. This avoids parameter mismatches caused by independently designing the trigger branch, pre-ignition sustaining branch, high-frequency drive, and state control, and ensures that the resulting structure corresponds to the aforementioned integrated circuit.

[0111] like Figure 9 As shown, to verify the design results of the high-voltage trigger branch, a voltage multiplier circuit simulation model was built in PLECS. In the simulation embodiment, the rectified input voltage is 311V, the turns ratio of the high-frequency transformer at the front end of the trigger path is 50:360, the AC peak voltage is approximately 2239.2V, and the voltage multiplier section adopts a five-stage boost unit voltage multiplier topology. Different trigger voltage values ​​correspond to different xenon lamp specifications and different design or test apertures: above 5kV is the trigger voltage requirement for other specifications of low-power xenon lamps; above 7kV is the minimum trigger voltage for the xenon lamp in this embodiment, i.e., U trig,min=7kV, which is the theoretical breakdown threshold of the xenon lamp (taking a 9mm×90mm×240mm xenon lamp as an example, with a gas pressure of 533kPa and an electrode spacing of 12mm, the breakdown threshold exceeds 7kV); greater than 15kV is the reliable triggering design target value determined in this application; greater than 18kV is the measured output voltage of the physical hardware prototype. This simulation uses 15kV as the reliable triggering design target, relative to U trig,min =7kV provides sufficient voltage margin to compensate for voltage loss caused by diode voltage drop, capacitor leakage current, and device parameter variations. Figure 9 The three voltage curves, from top to bottom, represent the first-stage output voltage, the second-stage output voltage, and the fifth-stage output voltage, corresponding to the voltage build-up process at the respective output nodes. Each curve gradually increases as the boost unit charges sequentially, with the fifth-stage output voltage eventually exceeding 15kV. This indicates that the determined input parameters of the first energy transfer path and the number of voltage multiplier stages enable the output voltage under trigger load conditions to meet the design requirements for reliable xenon lamp triggering.

[0112] like Figure 10 As shown, the input voltage of the LCC resonant circuit in the pre-burning sustaining simulation is 311V, and the switching frequency of the high-frequency drive unit is set to 172.6kHz. Figure 10 It includes two sets of simulated waveforms, with the upper curve U... simmer The xenon lamp pre-ignition sustaining voltage is shown on the vertical axis, with units of voltage / V; the lower curve I... simmer The xenon lamp pre-ignition sustaining current is shown on the vertical axis, with units of current / A. U simmer with I simmer Both waveforms are gradually established from zero, with an initial peak appearing during the startup phase, followed by oscillation convergence and a periodic stable operating state. Based on this simulation condition, the design stable value of the pre-ignition sustaining voltage is approximately 200V, and the design stable value of the pre-ignition sustaining current is approximately 2A. These simulation results are used to verify the design results of the pre-ignition sustaining branch formed by the high-frequency transformer turns ratio, LCC resonant parameters, switching frequency, and the rectification configuration of the pre-ignition sustaining branch.

[0113] like Figure 11 The image shows the xenon lamp trigger. The measured waveforms throughout the pre-combustion process. V trigger The high-voltage trigger voltage across the xenon lamp is measured at the test points located across the xenon lamp load, using a high-voltage differential probe with a voltage divider ratio of 5000:1. simmer The current in the xenon lamp main circuit is measured at the sampling point in the xenon lamp circuit series, using a current probe. The measured waveform shows I... simmer The instantaneous current at the moment of triggering the xenon lamp breakdown is less than 250mA. This value represents only the brief pulse current at the onset of xenon lamp breakdown, and this instantaneous current at the moment of triggering is not used as a basis for determining the completion of pre-ignition. triggerThis indicates the time required for the xenon lamp to transition from a non-breakdown state to a breakdown state. The pre-ignition completion determination uses the steady-state filtered average current obtained after the xenon lamp pre-ignition is established, through hardware RC filtering and software moving average, with a determination threshold greater than 1A. The instantaneous small current during triggering breakdown and the steady-state current for pre-ignition determination belong to different operating stages of the xenon lamp, and their physical meanings are different. The measured waveform can completely reflect the entire process from high-voltage trigger output, xenon lamp breakdown, to the establishment of the pre-ignition steady state.

[0114] like Figure 12 As shown, in the original low-frequency pre-ignition circuit with Under the experimental conditions, the red curve represents the sustaining voltage, the blue curve represents the sustaining current, and the equivalent resistance of the xenon lamp marked in the figure is approximately... (i.e. U simmer with I simmer The ratio (also the dynamic resistance under xenon lamp pre-ignition conditions) shows significant periodic fluctuations and glitches in both the sustaining voltage and sustaining current, indicating a low degree of compatibility between the pre-ignition sustaining energy and the xenon lamp dynamic resistance at this operating frequency and corresponding resonant parameters. Figure 12 The obtained dynamic resistance and sustained waveform state are used as Figure 13 Operating conditions input for pulse discharge experiment.

[0115] like Figure 13 The figure shows the waveform of a pulse discharge comparison experiment under low-frequency pre-ignition conditions; this experiment uses the same waveform as... Figure 12 Under completely identical test conditions, using the same xenon lamp, with the pre-ignition sustaining circuit operating at a frequency of 60kHz and the resonant parameters remaining constant, Figure 12 A subsequent energy storage pulse discharge is applied based on the established pre-combustion steady state. Figure 13 The waveform includes three measured curves: trigger voltage, trigger current, and discharge voltage. The criteria for judging each phenomenon are as follows: ① Secondary trigger judgment: The pre-ignition arc should remain conductive. If a high-voltage spike pulse reappears in the waveform at the moment the energy storage discharge is applied, it indicates that the xenon lamp has experienced a brief arc extinction and the system outputs a high-voltage trigger pulse again, indicating a secondary trigger phenomenon; ② Discharge failure judgment: After the discharge command is issued, if the discharge voltage does not drop as expected significantly and rapidly, and the stored energy cannot be released to the xenon lamp load; and if repeated secondary trigger pulses occur, it indicates that the xenon lamp arc has lost stability and is frequently extinguishing, indicating a discharge failure.

[0116] like Figure 14 As shown, in the high-frequency pre-ignition circuit with Under the experimental conditions, the red curve represents the sustaining voltage, the blue curve represents the sustaining current, and the equivalent resistance of the xenon lamp marked in the figure is approximately... .and Figure 12In comparison, the periodic waveforms of the sustaining voltage and sustaining current are smoother, indicating that after configuring the LCC resonant parameters and switching frequency according to the dynamic resistance characteristics, the pre-ignition sustaining branch can establish a more sufficient pre-ignition state. Figure 14 The obtained dynamic resistance and sustained waveform state are used as Figure 15 Operating conditions input for pulse discharge experiment.

[0117] like Figure 15 As shown, an optimized high-frequency pre-combustion plate was used to conduct a pulse discharge experiment; this experiment and Figure 12 , Figure 13 Using the same xenon lamp load, the pre-ignition sustaining circuit employs optimized LCC resonant parameters, with the high-frequency drive unit operating at a frequency of 172.6kHz. Periodic pulse discharges are applied after the pre-ignition state is fully established. Figure 15 The red curve represents the trigger voltage, the blue curve represents the trigger current, and the yellow curve represents the discharge voltage. The time interval between two adjacent discharge pulses is approximately 3.33 ms, based on the period. The frequency conversion relationship f=1 / T yields a pulse discharge frequency of approximately 300Hz. After repeated experiments and the acquisition of multiple sets of test waveforms, no pulse discharge was observed. Figure 13 The secondary triggering and discharge failure phenomena are shown. Figure 14 and Figure 15 The results show that, under these experimental conditions, matching the LCC resonant parameters and high-frequency drive frequency with the dynamic resistance characteristics of the xenon lamp is beneficial to improving the pre-combustion efficiency and discharge recovery reliability.

[0118] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An integrated circuit for high-voltage triggering and pre-combustion maintenance of a xenon lamp, characterized in that, The circuit includes: A high-frequency drive unit is used to generate a high-frequency drive signal and adjust the high-frequency drive signal according to a drive adjustment command; A high-frequency power conversion unit, connected to the high-frequency drive unit, is used to perform high-frequency conversion on the input electrical energy according to the high-frequency drive signal to obtain high-frequency electrical energy. The LCC resonant converter unit, connected to the high-frequency power conversion unit, includes a resonant network and a high-frequency transformer, and is used to resonantly convert the high-frequency electrical energy and transmit the resonant converted electrical energy to the output side of the high-frequency transformer. Both the high-voltage triggering branch and the pre-ignition sustaining branch are coupled to the output side of the same high-frequency transformer and connected to the xenon lamp; wherein, the high-voltage triggering branch includes a multi-stage diode-capacitor voltage multiplier structure, used to provide trigger voltage to the xenon lamp that has not broken down; the pre-ignition sustaining branch is used to rectify the electrical energy output by the high-frequency transformer and provide pre-ignition sustaining electrical energy to the xenon lamp that has broken down; The status sampling and control unit is connected to the xenon lamp and the high-frequency drive unit, respectively, and is used to acquire xenon lamp voltage sampling information and xenon lamp current sampling information, determine the xenon lamp operating status based on the xenon lamp voltage sampling information and xenon lamp current sampling information, and generate the drive adjustment command based on the xenon lamp operating status to adjust the electrical energy transmitted to the high-voltage trigger branch and the pre-combustion sustaining branch through the high-frequency transformer.

2. The circuit according to claim 1, characterized in that, The output side of the high-frequency transformer forms a first energy transmission path and a second energy transmission path. The first energy transmission path connects the high-frequency transformer and the high-voltage trigger branch, and is used to transmit the electrical energy output by the high-frequency transformer to the multi-stage diode-capacitor voltage multiplier structure; The second energy transmission path connects the high-frequency transformer and the pre-combustion sustaining branch, and is used to transmit the electrical energy output by the high-frequency transformer to the pre-combustion sustaining branch; The output terminals of the high-voltage triggering branch and the pre-combustion sustaining branch are respectively connected to the xenon lamp, so that the first energy transmission path and the second energy transmission path share the high-frequency transformer and respectively undertake the triggering power transmission and the pre-combustion sustaining power transmission.

3. The circuit according to claim 2, characterized in that, The multi-stage diode-capacitor voltage multiplier structure includes multiple cascaded boost units, each of which includes a diode and a capacitor. The boost units are connected in a manner that rectifies, stores, and superimposes the electrical energy transmitted through the first energy transmission path. The number of stages in the boost unit and the capacitance value of each capacitor are configured according to the minimum trigger voltage of the xenon lamp, the input voltage of the first energy transmission path, the trigger load current, the high-frequency drive frequency, and the allowable voltage ripple, so that the output voltage of the multi-stage diode-capacitor voltage multiplier structure under the trigger load condition is not lower than the minimum trigger voltage of the xenon lamp. The high-voltage triggering branch also includes a high-resistance network connected between the output terminal of the multi-stage diode-capacitor voltage multiplier structure and the xenon lamp. The high-resistance network is used to adjust the triggering voltage and release the residual charge after the xenon lamp breaks down.

4. The circuit according to claim 1, characterized in that, The resonant network includes a series resonant inductor, a series resonant capacitor, and a parallel resonant capacitor; The series resonant inductor and the series resonant capacitor are connected in series between the output terminal of the high-frequency power conversion unit and the input terminal of the high-frequency transformer, and the parallel resonant capacitor is connected to the input terminal of the high-frequency transformer. The pre-combustion sustaining branch includes a rectifier circuit and an output filter energy storage element. The input terminal of the rectifier circuit is connected to the output side of the high-frequency transformer, and the output terminal of the rectifier circuit is connected to the xenon lamp via the output filter energy storage element to obtain the pre-combustion sustaining electrical energy supplied to the xenon lamp.

5. The circuit according to claim 4, characterized in that, The turns ratio of the high-frequency transformer is configured according to the input voltage range of the high-frequency power conversion unit and the target voltage for xenon lamp pre-ignition. The inductance value of the series resonant inductor, the capacitance value of the series resonant capacitor, and the capacitance value of the parallel resonant capacitor are configured according to the xenon lamp pre-ignition target voltage, the xenon lamp pre-ignition target current, and the dynamic resistance characteristics of the xenon lamp pre-ignition stage, so as to form a resonant circuit impedance that is compatible with the dynamic resistance characteristics. The switching frequency of the high-frequency drive unit is configured according to the resonant frequency determined by the series resonant inductor and the series resonant capacitor, so that the pre-ignition sustaining voltage and pre-ignition sustaining current output by the LCC resonant converter unit cover the xenon lamp pre-ignition target voltage and the xenon lamp pre-ignition target current.

6. The circuit according to claim 1, characterized in that, The high-frequency driving unit includes a pulse width modulation controller, an isolation driving circuit, and a gate driving network; The pulse width modulation controller is used to generate a first pulse width modulation signal and a second pulse width modulation signal having a preset phase relationship and a dead time according to the drive adjustment command; The isolation drive circuit is used to electrically isolate and drive the first pulse width modulation signal and the second pulse width modulation signal respectively, to obtain a first isolation drive signal and a second isolation drive signal; The gate drive network is used to generate a first gate drive signal and a second gate drive signal based on the first isolation drive signal and the second isolation drive signal, and to provide the first gate drive signal and the second gate drive signal to the power switching device in the high-frequency power conversion unit, respectively.

7. The circuit according to claim 6, characterized in that, The pulse width modulation controller is further configured to adjust the pulse width of the first pulse width modulation signal and the second pulse width modulation signal according to the soft-start timing sequence; The gate drive network includes a gate damping branch, a gate overvoltage suppression branch, and a gate charge release branch. The gate damping branch is used to suppress gate oscillation of the power switching device, the gate overvoltage suppression branch is used to limit the gate drive voltage, and the gate charge release branch is used to release gate charge during the turn-off process. The first isolation drive signal and the second isolation drive signal are processed by the gate drive network to form the first gate drive signal and the second gate drive signal provided to the corresponding power switching devices.

8. The circuit according to claim 1, characterized in that, The state sampling and control unit is configured as follows: Obtain the pre-ignition start command, the power supply unit operating status, and the energy storage circuit status, and determine the pre-ignition start conditions based on the power supply unit operating status and the energy storage circuit status; If the pre-ignition start-up conditions are met, an initial drive adjustment command is generated, and the xenon lamp voltage sampling information and the xenon lamp current sampling information are acquired. The xenon lamp voltage sampling information and the xenon lamp current sampling information are compared with the corresponding state judgment thresholds to obtain the pre-ignition completion judgment result, and the xenon lamp working state is determined based on the pre-ignition completion judgment result. If the pre-ignition completion determination result is not completed, an updated drive adjustment command is generated based on the deviation between the xenon lamp voltage sampling information and the xenon lamp current sampling information and the corresponding state determination threshold. If the pre-combustion completion determination result is "complete", pre-combustion completion information is generated.

9. The circuit according to claim 8, characterized in that, The circuit also includes a downstream power circuit and an isolation control unit. The isolation control unit is connected to the state sampling and control unit and is used to control the on / off state of the downstream power circuit according to the circuit control command. The state sampling and control unit is also configured to: start the pre-ignition timing when the initial drive adjustment command is generated, and obtain the pre-ignition duration; If the pre-ignition completion information is generated before the pre-ignition duration reaches the preset timeout time, a circuit connection command for connecting the subsequent power circuit is generated after a preset delay time. If the pre-ignition duration reaches the preset timeout period and the pre-ignition completion information is not generated, a pre-ignition stop command is generated to stop the high-frequency drive unit and the pre-ignition retry count is updated. When the updated number of pre-ignition retry attempts does not reach the preset maximum number of retry attempts and the preset retry interval is met, a pre-ignition restart command for restarting the high-frequency drive unit is generated. When the updated number of pre-ignition retries reaches the preset maximum number of retries, a pre-ignition failure message and a circuit disconnection command for disconnecting the subsequent power circuit are generated to keep the subsequent power circuit in a disconnected state.

10. A structural and parameter design method for an integrated circuit for high-voltage triggering and pre-ignition maintenance of a xenon lamp, characterized in that, The method includes: Obtain circuit design information, which includes input voltage range, minimum trigger voltage of xenon lamp, target voltage for xenon lamp pre-ignition, target current for xenon lamp pre-ignition, dynamic resistance characteristics of xenon lamp pre-ignition stage, high-frequency power conversion drive constraints, and xenon lamp state determination conditions. Based on the minimum trigger voltage of the xenon lamp and the input parameters of the trigger branch in the circuit design information, the number of voltage multiplication stages, capacitor parameters, and high-impedance network parameters of the multi-stage diode-capacitor voltage multiplication structure are determined to obtain the design results of the high-voltage trigger branch. Based on the input voltage range, the xenon lamp pre-ignition target voltage, the xenon lamp pre-ignition target current, and the dynamic resistance characteristics, the resonance parameters of the LCC resonant network, the turns ratio of the high-frequency transformer, and the rectification configuration of the pre-ignition sustaining branch are determined, and the design results of the pre-ignition sustaining branch are obtained. Based on the design results of the high-voltage triggering branch and the pre-ignition sustaining branch, a first energy transmission path and a second energy transmission path connecting the high-voltage triggering branch and the pre-ignition sustaining branch are determined on the output side of the same high-frequency transformer, and the connection relationship between the high-voltage triggering branch, the pre-ignition sustaining branch and the xenon lamp is determined to obtain the integrated output structure design result. Based on the resonance parameters and the high-frequency power conversion drive constraints, the switching control requirements of the high-frequency power conversion unit, the high-frequency drive parameters, and the drive relationship between the high-frequency drive signal and the high-frequency power conversion unit are determined, and the drive conversion design results are obtained. Based on the xenon lamp state determination conditions, xenon lamp voltage sampling parameters, xenon lamp current sampling parameters, and the drive conversion design results, the feedback control relationship between the xenon lamp working state and the drive adjustment parameters is determined, and the state feedback control design results are obtained. Based on the design results of the high-voltage triggering branch, the design results of the pre-ignition sustaining branch, the design results of the integrated output structure, the design results of the drive conversion, and the design results of the state feedback control, the structure and parameters of the integrated circuit for xenon lamp high-voltage triggering and pre-ignition sustaining are configured to obtain the integrated circuit design results.

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