A method and system for ignition control suitable for high energy scenarios

Abstract

The application relates to a kind of ignition control method and system suitable for large energy scene.The method part mainly includes: receiving the signal of crankshaft timing disc sensor;When ignition time arrives, turn on discharge switch to make energy storage capacitor discharge to primary side winding of ignition coil, output initial pulse;During initial pulse output, by current sampling unit, real-time acquisition of primary side current waveform is carried out at preset high-frequency sampling rate, and the change slope of primary side current is calculated in real time;After determining that spark plug gap has been broken down, turn off discharge switch to end initial pulse, and after preset interval time, cut in maintenance pulse sequence, and maintenance pulse sequence is discharged to primary side winding by multiple times by turning on discharge switch to make energy storage capacitor, to maintain spark continuous combustion.The application can realize accurate closed-loop control of ignition pulse based on the real breakdown state of spark plug, so that the ignition controller can self-adaptively guarantee ignition reliability under different coils and different working conditions.

Description

Technical Field

[0001] This application relates to the field of ignition control technology, and in particular to an ignition control method and system suitable for high-energy scenarios. Background Technology

[0002] In high-power gas internal combustion engines such as gas generator sets, the ignition controller is a key component ensuring reliable engine operation. Existing ignition controllers typically employ a microprocessor-controlled capacitor discharge ignition architecture. Its basic working principle is as follows: the controller receives signals from the crankshaft timing disc sensor to determine the cylinder position and ignition timing. The internal microprocessor controls the boost circuit to charge the energy storage capacitor to several hundred volts. At the ignition timing, the discharge switch is triggered to conduct, causing the energy storage capacitor to discharge to the primary winding of the ignition coil. The secondary winding induces a high voltage to drive the spark plug and generate a spark.

[0003] However, in actual ignition, the timing of spark plug breakdown is significantly random, influenced by various factors such as cylinder pressure, air-fuel mixture concentration, spark plug gap condition, and ignition coil temperature. Existing ignition controllers generally employ an open-loop control strategy during the discharge phase, where the microprocessor controls the discharge switch's on-time according to pre-set fixed time parameters, making it impossible to detect whether the spark plug has actually broken down during the discharge process. When using a multi-pulse ignition strategy, the switching time between the initial pulse and subsequent sustaining pulse is also fixed and preset. This fixed-time switching strategy leads to: premature switching to the sustaining pulse before the secondary spark has reliably broken down, causing the primary spark to fail and misfire; or continued output of the initial pulse after spark breakdown, causing the ignition coil core to approach magnetic saturation, resulting in a sharp increase in primary current and a risk of overcurrent damage to the discharge switch. Furthermore, when replacing different ignition coil models, the fixed discharge time parameters cannot match the electrical characteristics of the new coil due to differences in inductance and internal resistance, requiring manual recalibration.

[0004] Given the above, how to overcome the randomness of spark plug breakdown time and the nonlinear influence of ignition coil magnetic saturation, and achieve precise adaptive switching control of ignition pulse based on the actual breakdown state of spark plug, is a problem to be solved in this technical field. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this application provides an ignition control method and system suitable for high-energy scenarios. It employs a method of setting a current sampling unit in the primary circuit of the ignition coil and acquiring the primary current waveform in real time at a high-frequency sampling rate. A microprocessor calculates the current change slope in real time and captures characteristic abrupt changes reflecting spark plug breakdown and core magnetic saturation. Based on this, it adaptively controls the timing of the initial pulse's termination and the timing of the sustain pulse sequence's entry, thereby achieving precise closed-loop control of the ignition pulse based on the actual spark plug breakdown state. This ensures that the ignition controller can adaptively guarantee ignition reliability under different coils and operating conditions.

[0006] The embodiments of this application adopt the following technical solutions: Firstly, this application provides an ignition control method suitable for high-energy scenarios, comprising: The system receives signals from the crankshaft timing disk sensor, determines the ignition timing of each cylinder based on the received signals, and controls the boost circuit to charge the energy storage capacitor to a preset voltage threshold before the ignition timing arrives. When the ignition moment arrives, the discharge switch is turned on to discharge the energy storage capacitor to the primary winding of the ignition coil, and an initial pulse is output. During the output of the initial pulse, the primary current waveform is collected in real time by the current sampling unit at a preset high-frequency sampling rate, and the slope of the change of the primary current is calculated in real time. Real-time monitoring of the abrupt change characteristics of the slope: When the primary current is detected to drop momentarily during its rise or oscillation, and the slope changes from a positive value to a negative value and then returns to a positive value, it is determined that the spark plug gap on the secondary side of the ignition coil has been broken down. After determining that the spark plug gap has been broken down, the discharge switch is turned off to end the initial pulse, and a sustaining pulse sequence is entered after a preset interval. The sustaining pulse sequence maintains the continuous combustion of the spark by repeatedly turning on the discharge switch to discharge the energy storage capacitor to the primary winding. The number of pulses and the duty cycle in the sustaining pulse sequence are dynamically adjusted according to the current operating parameters of the engine.

[0007] Through the above technical solution, the primary side current waveform is acquired in real time at a high frequency sampling rate and its change slope is calculated during the initial pulse output. The current drop caused by the sudden change in secondary impedance reflected to the primary side at the moment of spark plug breakdown is used as the switching criterion for the end of the initial pulse and the start of the maintenance pulse. This achieves precise closed-loop switching control of the ignition pulse based on the actual breakdown state of the spark plug, overcomes the mismatch problem of fixed-time switching strategy caused by the randomness of the spark plug breakdown time, and enables the ignition controller to adaptively ensure reliable establishment of the main spark under different cylinder pressures, air-fuel mixture concentrations and coil conditions.

[0008] In some implementations, if the first abrupt change feature is not detected during the initial pulse output, the slope of change is monitored. When the slope of the change is detected to continue to increase and exceed the preset magnetic saturation warning slope threshold, it is determined that the iron core of the ignition coil has entered a magnetic saturation state, generating a second abrupt change characteristic. In response to the second mutation feature, the discharge switch is forcibly shut off and the current ignition window is terminated.

[0009] The above technical solution utilizes the same current sampling channel to simultaneously monitor breakdown characteristics and magnetic saturation characteristics during the initial pulse. When the iron core enters a magnetic saturation state, causing a sudden drop in inductance and a sharp rise in current, the discharge switch is forcibly shut off in time, preventing damage to the discharge switch due to overcurrent and providing hardware safety protection for the high-energy ignition controller.

[0010] In some embodiments, the method further includes the step of identifying the electrical parameters of the ignition coil during the discharge initiation phase of the initial pulse: During the preset initial sampling period after the discharge switch is turned on, the primary inductance of the ignition coil is calculated based on the rising slope of the primary current waveform and the current terminal voltage of the energy storage capacitor. The primary resistance of the ignition coil is calculated based on the decay rate of the primary current waveform after reaching its peak and the primary inductance. Based on the primary side inductance and the primary side internal resistance, the magnetic saturation warning slope threshold and the preset interval time are set.

[0011] Through the above technical solution, the inductance and internal resistance of the current ignition coil can be identified online by the current rise slope and decay rate at the beginning of the discharge. Based on this, the magnetic saturation warning slope threshold and the interval time for maintaining the pulse are dynamically set, so that the threshold parameters for subsequent breakdown judgment and saturation protection can be automatically adapted to the characteristics of the current coil. This eliminates the need for manual recalibration when replacing different models of ignition coils.

[0012] In some implementations, the number of pulses and the duty cycle in the sustain pulse sequence are dynamically adjusted according to the engine's current operating parameters, specifically including: The current speed and current load of the engine are obtained as the current operating condition parameters; In a pre-stored pulse parameter mapping table, using the current rotational speed and the current load as indexes, the target pulse count and target duty cycle corresponding to the current operating condition parameters are retrieved. According to the target number of pulses and the target duty cycle, the discharge switch is controlled to output each pulse in the sustaining pulse sequence in sequence.

[0013] The above technical solution establishes a correspondence between engine speed and load and the parameters of the sustaining pulse by using a pre-calibrated pulse parameter mapping table. This allows the output parameters of the sustaining pulse to be adjusted in real time according to changes in operating conditions. Under high load conditions, the number of pulses and duty cycle are increased to prolong the spark duration, while under light load conditions, the number of pulses is reduced to reduce energy consumption.

[0014] In some implementations, the preset high-frequency sampling rate is not less than 1MHz; the analog signal collected by the current sampling unit is amplified and filtered by the signal conditioning circuit and then input to the analog-to-digital converter input terminal of the microprocessor, and the low-pass filter cutoff frequency in the signal conditioning circuit is set to more than half of the preset high-frequency sampling rate.

[0015] The above technical solution acquires the primary current waveform at a high sampling rate of not less than 1MHz, and ensures the signal bandwidth by setting a reasonable filter cutoff frequency. This ensures that the microprocessor can capture the breakdown transient current drop characteristics with a duration of only microseconds, avoiding the omission of key abrupt changes due to insufficient sampling rate or insufficient signal bandwidth.

[0016] In some implementations, it also includes: After each successful detection of the first mutation feature, the actual duration from the on-time of the current initial pulse to the detection of the first mutation feature is recorded; The average of the actual durations recorded in the most recent consecutive ignition cycles is used as the historical average duration of breakdown. In the next ignition cycle, if the duration of the initial pulse exceeds a preset multiple of the average duration of the breakdown history and the first and second mutation features are still not detected, it is determined that the current cylinder has misfired, the discharge switch is turned off and a misfire alarm signal is output.

[0017] By using the above technical solution, a statistical benchmark is established by utilizing historical breakdown time and a misfire timeout criterion is set accordingly. In the absence of abnormalities such as neither breakdown characteristics nor magnetic saturation protection is triggered, misfires are identified and alarms are triggered in a timely manner, avoiding ineffective discharge and energy waste caused by faults such as severe spark plug damage or gas supply interruption.

[0018] In some implementations, the total duration of a single ignition window does not exceed 500 microseconds, and the total energy released by the energy storage capacitor within the single ignition window is not less than 500 millijoules.

[0019] The above technical solution limits the ignition window to within 500 microseconds and ensures an energy release of no less than 500 millijoules, thus meeting the dual requirements of high-power multi-cylinder gas generator sets for rapid response and high-energy ignition during high-speed operation.

[0020] Secondly, this application provides an ignition control system suitable for high-energy scenarios, comprising: A microprocessor, connected to a crankshaft timing disc sensor, is used to receive signals from the crankshaft timing disc sensor and determine the ignition timing of each cylinder. A boost circuit, connected to the microprocessor, is used to boost the external power supply voltage under the control of the microprocessor to charge the energy storage capacitor. A voltage sampling unit is connected between the energy storage capacitor and the microprocessor, and is used to collect the terminal voltage of the energy storage capacitor in real time and feed it back to the microprocessor. A discharge switch is connected between the energy storage capacitor and the primary winding of the ignition coil, and its on and off states are controlled by the microprocessor. A current sampling unit is connected in series in the discharge circuit of the primary winding to collect the primary current signal in real time at a preset high-frequency sampling rate and feed it back to the microprocessor. The microprocessor calculates the slope of the primary current signal in real time. When it detects a first abrupt change in the slope that indicates the spark plug gap has been broken down, it turns off the discharge switch to end the initial pulse and controls the discharge switch to be turned on multiple times after a preset interval to output a sustaining pulse sequence.

[0021] Through the above technical solution, the current sampling unit is introduced into the primary side discharge circuit and forms a high-speed closed-loop feedback path with the microprocessor. This enables the microprocessor to determine in real time whether the spark plug has been broken down based on the abrupt change characteristics of the primary side current change slope. Based on this, the microprocessor can accurately control the switching timing between the initial pulse and the sustaining pulse sequence, thus supporting the ignition pulse closed-loop control function based on the actual breakdown state from the hardware architecture level.

[0022] In some embodiments, the boost circuit adopts a push-pull topology and includes a push-pull transformer, a first switching transistor, a second switching transistor, and a rectifier and filter circuit. The primary winding of the push-pull transformer has a center tap, which is connected to the external power supply. The two ends of the primary winding are respectively connected to the first switch and the second switch. The secondary winding of the push-pull transformer has a center tap, which is connected to the reference ground of the primary side discharge circuit. The two ends of the secondary winding are respectively connected to the anodes of the first rectifier diode and the second rectifier diode. The cathodes of the first rectifier diode and the second rectifier diode are connected together and then connected to the energy storage capacitor through a filter inductor. The voltage sampling unit includes an isolated voltage conversion circuit. The input terminal of the isolated voltage conversion circuit collects the high voltage output of the energy storage capacitor, and its output terminal feeds back the stepped-down and isolated voltage signal to the analog-to-digital conversion input terminal of the microprocessor. The microprocessor adjusts the pulse width modulation signal output to the first switch and the second switch accordingly.

[0023] The above technical solution employs a single push-pull transformer with a center tap and a full-wave rectifier topology, resulting in a compact circuit structure and high bidirectional magnetization utilization of the transformer core. Combined with high-frequency PWM control and a real-time feedback loop for isolation voltage, the system can rapidly and accurately store large amounts of energy within the extremely short interval of the ignition cycle, while avoiding interference from the high-voltage side to the low-voltage control side.

[0024] In some embodiments, the current sampling unit includes a sampling resistor and a signal conditioning circuit; The sampling resistor is connected in series between the low-potential end of the primary winding and the reference ground; The signal conditioning circuit is connected between the sampling resistor and the analog-to-digital converter input terminal of the microprocessor, and is used to amplify and filter the voltage signal across the sampling resistor before inputting it into the microprocessor. The microprocessor is also connected to a communication interface, which is used to communicate with the engine control unit to obtain the current speed and current load of the engine. The microprocessor queries a pre-stored pulse parameter mapping table based on the obtained current speed and current load to obtain the target pulse number and target duty cycle, and controls the discharge switch to output the sustaining pulse sequence accordingly.

[0025] By using the above technical solution, the sampling resistor is set at the low potential end of the primary winding to simplify the signal conditioning circuit design. Real-time operating parameters are obtained from the engine control unit through the communication interface and the pulse parameter mapping table is used to automatically adjust the maintenance pulse parameters, thereby realizing the coordinated control of hardware sampling and operating condition adaptation.

[0026] In summary, this application includes at least the following beneficial technical effects: 1. By acquiring the primary side current waveform in real time at a high frequency sampling rate and calculating its change slope during the initial pulse output, the instantaneous current drop caused by the reflection of the sudden change in secondary impedance to the primary side at the moment of spark plug breakdown is used as the switching criterion between the initial pulse and the sustaining pulse sequence. This achieves precise closed-loop switching control of ignition pulse based on the actual breakdown state of the spark plug, overcoming the mismatch problem of fixed-time switching strategy caused by the randomness of the spark plug breakdown moment. 2. By using the same current sampling channel to simultaneously monitor breakdown characteristics and core magnetic saturation characteristics, the discharge switch is forcibly shut off in time when the core enters the magnetic saturation state, preventing overcurrent damage to the discharge switch caused by a sharp rise in primary current. Furthermore, the inductance and internal resistance of the ignition coil are identified online by the current rise slope and decay rate at the beginning of the discharge, enabling the magnetic saturation protection threshold to automatically adapt to different coils, thus eliminating the need for manual recalibration when replacing the coil. 3. By sequentially outputting the initial pulse and sustaining pulse sequence within a single ignition window of no more than 500 microseconds, and dynamically querying the number and duty cycle of sustaining pulses in the pulse parameter mapping table according to the current engine speed and load, the spark duration is adaptively adjusted according to the operating conditions, ensuring ignition reliability under high-energy conditions such as lean combustion and cold start under conditions of no less than 500 millijoules. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A block diagram of an ignition control system suitable for high-energy scenarios provided in this application embodiment; Figure 2 A flowchart illustrating an ignition control method suitable for high-energy scenarios, provided as an embodiment of this application; Figure 3 A schematic diagram of the primary current waveform and abrupt change characteristics within a single ignition window provided in an embodiment of this application; Figure 4 This is a block diagram of the overall closed-loop boost converter provided in an embodiment of this application; Figure 5 A schematic diagram of a push-pull circuit provided in an embodiment of this application; Figure 6 An overall control block diagram provided for embodiments of this application. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. Furthermore, the technical features involved in the various embodiments described below can be combined with each other as long as they do not conflict with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] Example 1: This embodiment explains the overall architecture and closed-loop control principle of the ignition control system.

[0031] It should be noted that existing ignition controllers employ an open-loop control strategy during the discharge phase, controlling the conduction sequence of the discharge switch based on fixed time parameters, and cannot detect whether the spark plug has actually been burned out. When a multi-pulse strategy is used, the switching time between the initial pulse and the sustaining pulse is fixed and preset. If the spark plug burn-out time changes randomly, there is a risk of misfire due to premature switching or magnetic saturation of the iron core due to premature switching.

[0032] To solve the above problems, refer to Figure 1 This embodiment provides an ignition control system suitable for high-energy scenarios, including a microprocessor, a boost circuit, an energy storage capacitor, a voltage sampling unit, a discharge switch, a current sampling unit, and a communication interface.

[0033] The microprocessor can be an STM32F407, equipped with a high-speed analog-to-digital converter and a maximum sampling rate of 2.4 MSPS (millions of samples per second), meeting the requirements for high-frequency sampling of the primary-side current waveform. The microprocessor connects to a crankshaft timing disk sensor to receive signals from the sensor and determine the ignition timing of each cylinder. The crankshaft timing disk sensor can be a Hall effect sensor or a magnetoelectric sensor, mounted on the crankshaft timing disk, outputting pulse signals corresponding to the cylinder position as the crankshaft rotates. By analyzing the timing relationship of these pulse signals, the microprocessor determines which cylinder is currently near its top dead center on compression, thus determining the ignition timing of that cylinder.

[0034] The boost circuit is connected to the microprocessor and, under the microprocessor's control, boosts the external power supply voltage to charge the energy storage capacitor. The external power supply voltage ranges from 24V to 30V. The boost circuit operates under the control of a pulse-width modulation signal output by the microprocessor, boosting the external power supply voltage to a range of 250V to 300V to charge the energy storage capacitor. The specific topology of the boost circuit will be described in detail in subsequent embodiments.

[0035] The voltage sampling unit is connected between the energy storage capacitor and the microprocessor. The voltage sampling unit employs a voltage divider sampling circuit, consisting of two series-connected voltage divider resistors connected between the positive terminal of the energy storage capacitor and a reference ground. The intermediate node of the voltage divider is connected to the analog-to-digital converter (ADC) input of the microprocessor. The microprocessor acquires the terminal voltage of the energy storage capacitor in real time through this ADC input. When the terminal voltage reaches a preset voltage threshold, the microprocessor shuts off the switching transistor in the boost circuit, stopping charging. The preset voltage threshold is calculated based on the target ignition energy and the capacitance of the energy storage capacitor using the energy formula E = 0.5 × C × V². For example, if the target ignition energy is 500 millijoules and the capacitance of the energy storage capacitor is 15 microfarads, the preset voltage threshold is approximately 258V.

[0036] A discharge switch is connected between the positive terminal of the energy storage capacitor and the high-potential end of the primary winding of the ignition coil, and its on / off state is controlled by a microprocessor. The discharge switch employs an insulated-gate bipolar transistor (IGBT), whose gate is connected to the microprocessor's general-purpose input / output (GPIO) port via a driver circuit. The microprocessor controls the on / off state of the discharge switch by controlling the high and low levels of this port, thereby controlling the timing and duration of the discharge from the energy storage capacitor to the primary winding of the ignition coil.

[0037] A current sampling unit is connected in series in the discharge circuit of the primary winding of the ignition coil. It is used to acquire the primary current signal in real time at a preset high-frequency sampling rate and feed it back to the microprocessor. In this embodiment, the preset high-frequency sampling rate is set to no less than 1MHz, meaning at least one current sample point is acquired every microsecond. The current sampling unit includes a sampling resistor and a signal conditioning circuit. The sampling resistor is connected in series between the low-potential end of the primary winding of the ignition coil and the reference ground. Its resistance value is selected to be between 0.05 ohms and 0.1 ohms to reduce the influence of the sampling resistor itself on the impedance of the discharge circuit. When current flows through the primary winding, a voltage drop proportional to the current is generated across the sampling resistor. The signal conditioning circuit is connected between the sampling resistor and the analog-to-digital converter input of the microprocessor. The signal conditioning circuit includes an operational amplifier and a low-pass filter. The operational amplifier amplifies the small sampled voltage to a voltage range (e.g., 0V to 3.3V) recognizable by the microprocessor's analog-to-digital converter. The cutoff frequency of the low-pass filter is set to more than half of the preset high-frequency sampling rate (for example, when the sampling rate is 1MHz, the cutoff frequency is not less than 500kHz) to filter out ultra-high frequency noise interference higher than the sampling rate during the discharge process, while retaining useful signals with microsecond-level transient characteristics.

[0038] refer to Figure 1The microprocessor is the core control unit of the entire system. It receives the primary current signal from the current sampling unit in real time and calculates the slope of this current signal, di / dt, in real time. The microprocessor simultaneously executes three judgment logics: first, it detects whether the slope of change exhibits a first abrupt change characteristic reflecting that the spark plug gap has been broken down; second, it detects whether the slope of change exhibits a second abrupt change characteristic reflecting that the iron core has entered a magnetic saturation state; and third, it performs a misfire timeout judgment based on historical breakdown duration statistics. When the first abrupt change characteristic is detected, the microprocessor shuts off the discharge switch to end the initial pulse and controls the discharge switch to conduct multiple times after a preset interval to output a sustaining pulse sequence. When the second abrupt change characteristic is detected, the microprocessor forcibly shuts off the discharge switch to protect the hardware. If no abrupt change characteristic is detected after exceeding the historically statistical timeout threshold, a misfire is determined, and an alarm is output.

[0039] The microprocessor is also connected to a communication interface used to communicate with the engine's control unit to obtain the engine's current speed and load. This communication interface can be a controller area network (CAN) bus interface. Based on the obtained current speed and load, the microprocessor looks up the corresponding sustaining pulse sequence parameters in a pre-stored pulse parameter mapping table.

[0040] Based on the above scheme, by introducing a current sampling unit into the primary discharge circuit and feeding it back to the microprocessor in real time at a high sampling rate of no less than 1MHz, the microprocessor can capture microsecond-level transient changes in current during the discharge process. Based on this, it can determine whether the spark plug has broken down and whether the iron core is approaching magnetic saturation, thus achieving precise closed-loop switching control based on the actual breakdown state of the spark plug. The system also integrates breakdown detection, magnetic saturation protection, and misfire diagnosis into the same current sampling channel, reducing the need for additional sensors.

[0041] Example 2: refer to Figure 2 As shown, this embodiment provides an ignition control method suitable for high-energy scenarios, which includes the following steps: S1: Receives signals from the crankshaft timing sensor and determines the ignition timing. The microprocessor receives pulse signals from the engine crankshaft timing sensor in real time. By capturing the missing tooth signal and counting pulses, it determines the current crankshaft angle of the engine. Combined with the camshaft phase signal, the microprocessor determines the current stroke of each cylinder and accurately calculates the ignition timing (i.e., the starting point of the ignition window) of each cylinder based on the preset ignition advance angle data.

[0042] S2: Control the boost circuit to charge the energy storage capacitor and determine the terminal voltage. Before the calculated ignition moment arrives (usually 1 to 2 milliseconds in advance), the microprocessor activates the PWM drive signal of the boost circuit to charge the energy storage capacitor using an external power supply. During charging, the microprocessor reads the terminal voltage of the energy storage capacitor in real time through the voltage sampling unit. The microprocessor continuously determines whether the terminal voltage reaches the preset voltage threshold (e.g., 258V) corresponding to the target energy of 500 millijoules. If it does not reach the threshold, charging continues; if it does, proceed to step S3.

[0043] S3: Stop charging and wait for ignition. When the voltage at the end of the energy storage capacitor reaches the preset voltage threshold, the microprocessor shuts off the PWM drive signal of the boost circuit, stops charging, and the energy storage capacitor enters a high-voltage holding state. The microprocessor waits for the ignition moment calculated in step S1 to arrive.

[0044] S4: The discharge switch outputs an initial pulse, and the high-frequency acquisition and calculation of di / dt are performed. When the exact ignition moment arrives, the microprocessor controls the discharge switch to turn on, and the high voltage of the energy storage capacitor is instantaneously applied to the primary winding of the ignition coil, generating an initial pulse. At this time, the analog-to-digital converter inside the microprocessor starts working synchronously at a high-frequency sampling rate of no less than 1MHz, intensively acquiring the current data fed back by the current sampling unit on the primary circuit, and calculating the real-time change slope di / dt of the primary current point by point. (In the first 20 to 50 microseconds of this stage, the microprocessor simultaneously uses the initial rising slope and the subsequent decay slope to identify the inductance and internal resistance of the ignition coil online in order to set the subsequent protection threshold).

[0045] Core mutation feature judgment logic: While S4 continues, the microprocessor monitors the mutation features of di / dt in real time and executes the following branch judgment: Determining breakdown (first abrupt change characteristic): The microprocessor detects whether di / dt changes from a positive value to a negative value and then recovers to a positive value, with a momentary drop in current. If this characteristic is detected, it indicates that the secondary spark plug has successfully broken down, and the process jumps directly to step S5.

[0046] Magnetic saturation detection (second abrupt change characteristic): If no breakdown is detected, the microprocessor checks whether di / dt has increased abnormally and exceeded the magnetic saturation warning slope threshold dynamically calculated based on the coil inductance. If it exceeds this threshold, the core is determined to be magnetically saturated, and the microprocessor immediately forces the discharge switch to shut off, terminating the current cylinder's ignition window to protect the hardware.

[0047] Fire timeout detection: If neither breakdown nor saturation occurs, the microprocessor checks whether the current discharge duration has exceeded a preset multiple (e.g., 2 times) of the historical average breakdown duration. If the timeout occurs, it is determined to be a serious fire, the microprocessor forcibly shuts off the discharge switch, and outputs a fire alarm signal to the outside.

[0048] S5: Upon determining a breakdown, the discharge switch is turned off, ending the initial pulse. Once the spark plug is confirmed to have broken down in the above checks, the microprocessor no longer blindly extends the discharge time but immediately turns off the control signal of the discharge switch, actively ending the initial pulse. At this point, the primary current is no longer driven by the applied voltage but begins to decay through the freewheeling circuit.

[0049] S6: Record the actual duration of this initial pulse. The microprocessor will store the precise time difference (in microseconds) from the start of S4 conduction to the breakdown determination time in S5 into the historical statistics buffer. This buffer is used to update the historical average breakdown duration and provide an adaptive data benchmark for the timeout error prevention judgment (misfire diagnosis) of the next ignition.

[0050] S7: Wait for preset interval time. The microprocessor starts timing after the discharge switch is turned off, waiting for a preset interval time. This interval time is calculated from the previously identified coil inductance and internal resistance, and its purpose is to allow the reverse recovery process on the first side to complete, preventing a current surge when the next pulse is turned on.

[0051] S8: Obtain real-time engine operating conditions and query the pulse parameter mapping table. During the waiting interval, the microprocessor reads the current engine speed (e.g., 1500 r / min) and current load percentage (e.g., 75%) broadcast by the engine control unit via the CAN bus communication interface. Subsequently, it looks up the target number of pulses (e.g., 4) and target duty cycle (e.g., 55%) corresponding to the current operating condition in the two-dimensional pulse parameter mapping table pre-stored in Flash memory.

[0052] S9: Outputs a sustain pulse sequence, ending the current ignition window. After the interval ends, the microprocessor, according to the quantity and duty cycle parameters queried in S8, alternately turns the discharge switch on and off again, allowing the remaining high-voltage energy in the energy storage capacitor to enter the ignition coil in stages, forming a continuous arc at the secondary spark plug to sustain energy. When the set number of sustain pulses has been output, the microprocessor completely turns off the discharge switch. At this point, the closed-loop adaptive ignition window with a total duration not exceeding 500 microseconds has ended, the microprocessor resets, and prepares for the ignition of the next cylinder.

[0053] Example 3: This embodiment provides a detailed explanation of the breakdown determination based on the abrupt change in the slope of the primary current change.

[0054] It should be noted that during capacitor discharge ignition, when the energy storage capacitor discharges to the primary winding of the ignition coil, a high voltage is induced in the secondary winding. Before breakdown, the spark plug gap exhibits extremely high impedance (approximately open circuit). After breakdown, ionization creates a plasma channel, and the impedance drops sharply to an extremely low value. This abrupt change in secondary impedance is reflected back to the primary side through the electromagnetic coupling of the transformer, causing a detectable transient characteristic in the primary side current waveform. However, existing controllers do not perform high-speed sampling and analysis of the primary side current during the discharge process; therefore, this physical phenomenon cannot be used to determine whether the spark plug has actually broken down.

[0055] refer to Figure 2 and Figure 3 This embodiment describes in detail the process by which the microprocessor determines spark plug breakdown based on the abrupt change in the slope of the primary current change.

[0056] At the moment of ignition, the microprocessor controls the discharge switch to turn on, and the energy storage capacitor begins to discharge to the primary winding of the ignition coil, outputting an initial pulse. During the initial pulse output, the current sampling unit acquires the primary current waveform in real time at a preset high-frequency sampling rate of not less than 1MHz. The microprocessor calculates the current change slope di / dt at each sampling point. The calculation method is: subtract the current value of the previous sampling point from the current value of the current sampling point, and then divide by the sampling period.

[0057] refer to Figure 3 In the lower half of the discharge, during the initial discharge phase, the primary current rises rapidly from zero. The slope of this change, di / dt, is positive and relatively large during this phase. As the current approaches its peak, the rate of increase gradually slows, and the slope decreases but remains positive.

[0058] At the instant the spark plug gap breaks down, the secondary equivalent impedance drops abruptly from a near-open circuit state to the low-impedance state of the plasma channel. This sudden impedance change is reflected to the primary side through the primary-secondary coupling of the transformer, causing a very short-lived (typically 2 to 10 microseconds) instantaneous drop in the primary side current waveform. (Reference) Figure 3 The area marked with a dashed circle in the diagram represents the drop as follows: during the rise or oscillation of the primary current, a sudden, instantaneous decrease occurs, with the slope di / dt abruptly changing from positive to negative; subsequently, as a stable current path is established on the secondary side, the primary current resumes its rise or tends to stabilize, and the slope di / dt returns to a positive value. This abrupt change in slope from positive to negative to positive is the first abrupt change characteristic.

[0059] The microprocessor's decision logic is as follows: During the initial pulse output, the microprocessor detects the sign change of the change slope di / dt point by point. When a sudden change in the change slope di / dt from positive to negative is detected, a breakdown confirmation window (e.g., 10 microseconds) is initiated. Within this confirmation window, if the change slope di / dt returns to a positive value, and the current drop exceeds a preset drop threshold (e.g., 5% of the peak current), the first abrupt change characteristic is confirmed, and the spark plug gap is determined to have broken down. The purpose of setting the drop amplitude threshold and the confirmation window is to eliminate false judgments caused by sampling noise or discharge oscillations.

[0060] After determining that the spark plug gap has been broken down, the microprocessor shuts off the discharge switch to end the initial pulse. The purpose of maintaining the initial pulse after breakdown confirmation is to allow the main spark to establish a stable flame core supported by the remaining energy of the initial pulse. Based on the primary current value at the moment of breakdown confirmation and the identified coil parameters (inductance and internal resistance, identification method described in subsequent embodiments), the microprocessor calculates the time required for the current to decay to a preset sustaining current threshold, and shuts off the discharge switch after this time is reached.

[0061] Based on the above scheme, by acquiring the primary side current in real time at a high-frequency sampling rate and calculating its change slope, and using the current drop characteristic (first abrupt change characteristic) caused by the sudden change in secondary impedance reflected to the primary side at the moment of spark plug breakdown as a criterion, online real-time determination of whether the spark plug has actually broken down is achieved. This determination method relies only on the current sampling signal of the primary side and does not require any additional detection elements on the high-voltage secondary side, thus avoiding insulation and electromagnetic compatibility problems caused by high-voltage side wiring.

[0062] Example 4: This embodiment provides a detailed explanation of the online identification and threshold adaptation of the electrical parameters of the ignition coil.

[0063] It should be noted that different ignition coil models have different primary-side inductance and primary-side internal resistance. If control parameters such as the magnetic saturation warning slope threshold and the interval time for sustaining pulse entry remain unchanged, these parameters may no longer match the characteristics of the new coil after replacement, leading to insufficient protection sensitivity or false triggering.

[0064] refer to Figure 2 and Figure 3 This embodiment describes the process by which the microprocessor identifies the electrical parameters of the ignition coil during the initial discharge phase of the initial pulse and dynamically sets the subsequent control threshold accordingly.

[0065] Within a preset initial sampling period after the discharge switch is turned on (e.g., the first 20 to 50 microseconds after turn-on), the microprocessor continuously acquires multiple primary-side current values ​​at a high-frequency sampling rate. (Reference) Figure 3The "rising slope" interval is marked in the diagram, during which the primary current rises approximately linearly. The microprocessor performs differential calculations on the acquired current values ​​to obtain the average value of the current rising slope dI / dt.

[0066] Based on the equivalent circuit model of the primary side of the ignition coil during the initial discharge phase, since the sampling resistor value is much smaller than the primary side internal resistance and the time is extremely short (the capacitor voltage hardly drops), the rising slope of the primary side current approximately satisfies dI / dt≈V_cap / L1, where V_cap is the current terminal voltage of the energy storage capacitor (recorded by the voltage sampling unit at the end of charging), and L1 is the primary side inductance of the ignition coil. The microprocessor thus calculates the primary side inductance L1=V_cap / (dI / dt).

[0067] refer to Figure 3 The "attenuation rate" range marked in the diagram indicates that the primary current begins to decay after reaching its peak. The microprocessor continues to collect current values ​​during the current decline phase and calculates the attenuation rate. The current decay approximately follows an exponential decay law: I(t) = I_peak × exp(-R1 × t / L1). Using the calculated primary inductance L1, the detected peak current I_peak, and the current values ​​at two sampling points during the decay process, the microprocessor calculates the primary internal resistance R1.

[0068] After identifying the inductance and internal resistance, the microprocessor dynamically sets subsequent control parameters accordingly: First, set the magnetic saturation warning slope threshold: When the iron core enters a magnetic saturation state, the effective inductance drops sharply to a fraction of its normal value, causing the current rise slope to increase dramatically. The microprocessor sets the magnetic saturation warning slope threshold to a preset multiple (e.g., 3 to 5 times) of the normal rise slope. Since the normal rise slope has been calculated using V_cap / L1, this threshold automatically adapts to the current coil inductance.

[0069] Second, a preset interval time is set: the interval time between the end of the initial pulse and the start of the sustain pulse sequence needs to meet the requirements for the completion of the reverse recovery process in the discharge circuit. This recovery time is related to the time constant τ = L1 / R1 of the primary circuit. The microprocessor calculates the time constant τ based on the identified L1 and R1, and sets the preset interval time to a preset proportion of τ (e.g., 0.1τ to 0.3τ), so that the interval time automatically adapts to the characteristics of the current coil.

[0070] In subsequent ignition cycles, the microprocessor monitors the rate of change in the current rise. If the rate of change is within a preset tolerance (e.g., ±10%), the identified electrical parameters are used. If a significant change in the rate of change is detected (outside the tolerance), indicating that the ignition coil may have been replaced, the parameter identification process is automatically re-executed.

[0071] Based on the above scheme, the inductance and internal resistance of the ignition coil are identified online during the initial discharge phase by utilizing the current rise slope and decay rate. Based on this, the magnetic saturation warning slope threshold and the sustain pulse entry interval are automatically set, ensuring that all subsequent control threshold parameters dynamically match the actual characteristics of the current coil. When replacing ignition coils with different models, the system automatically completes parameter identification and threshold updates during the first ignition process, requiring no manual calibration.

[0072] Example 5: This embodiment provides a detailed description of core magnetic saturation protection and fire fault diagnosis.

[0073] It should be noted that in high-energy ignition scenarios, if the spark plug fails to break down due to severe carbon buildup or an excessively large gap, the initial pulse will continue to be output. As the discharge time increases, the magnetic flux density in the ignition coil core continuously increases. Once it exceeds the saturation magnetic flux density of the core material, the inductance will drop sharply, and the primary current will rapidly rise above the rated current of the discharge switch in a very short time, causing overcurrent damage to the discharge switch. Furthermore, if the spark plug completely fails or the gas supply is interrupted, it is necessary to promptly identify the misfire state and trigger an alarm in the absence of a breakdown.

[0074] refer to Figure 2 and Figure 3 This embodiment describes the process by which the microprocessor performs magnetic saturation protection and misfire diagnosis during the initial pulse.

[0075] During the initial pulse output, if the microprocessor does not detect the first abrupt change characteristic reflecting spark plug breakdown, it continues to acquire the primary side current at a high-frequency sampling rate and calculate the change slope di / dt.

[0076] The microprocessor continuously monitors the changing trend of the slope di / dt. (Reference) Figure 3 The dashed line indicates the magnetic saturation condition. When the iron core approaches magnetic saturation, the inductance begins to decrease rapidly, the rate of increase of the primary current accelerates significantly, and the slope di / dt suddenly changes from a normal decay state to a rapid increase. When the microprocessor detects that the slope di / dt continues to increase and exceeds the preset magnetic saturation warning slope threshold, it determines that the iron core has entered a magnetic saturation state, generating the second abrupt change characteristic.

[0077] In response to the second abrupt change, the microprocessor immediately forces the gate drive signal of the discharge switch to shut off, cutting off the discharge path from the energy storage capacitor to the primary winding and terminating the current ignition window. The response time of this protection action, from detecting the second abrupt change to the complete shutdown of the discharge switch, does not exceed 5 microseconds, ensuring that the primary current does not rise beyond the safe operating range of the discharge switch. The method for setting the magnetic saturation warning slope threshold has been described in the foregoing embodiments; its value is adaptively determined based on the current inductance of the coil.

[0078] In terms of misfire diagnosis, after each successful detection of the first abrupt change characteristic (i.e., successful breakdown), the microprocessor records the actual duration from the initial pulse being turned on by the discharge switch to the detection of the first abrupt change characteristic. The microprocessor maintains a first-in-first-out circular buffer to store the actual duration recorded in the most recent N consecutive ignition cycles (e.g., N=16), and calculates the average of these N values ​​as the historical average duration of breakdown.

[0079] In the next ignition cycle, if the duration of the initial pulse exceeds a preset multiple (e.g., twice) of the historical average duration of breakdown, and neither the first abrupt change characteristic (no breakdown) nor the second abrupt change characteristic (no saturation) is detected, the microprocessor determines that a misfire has occurred in the current cylinder. The microprocessor shuts off the discharge switch to terminate the current ignition window and outputs a misfire alarm signal to the engine control unit via the communication interface. Simultaneously, a local alarm can be triggered via an indicator light on the controller.

[0080] Based on the above scheme, by using the same current sampling channel to simultaneously perform three functions—breakdown detection, magnetic saturation protection, and fire diagnosis—the discharge switch is forcibly shut off in time when the iron core approaches saturation to prevent overcurrent damage. When there is an abnormality but no breakdown, a fire is promptly identified and an alarm is triggered, forming a complete safety protection and fault diagnosis system. This significantly improves the safety and maintainability of the high-energy ignition controller under harsh operating conditions.

[0081] Example 6: This embodiment provides a detailed description of the push-pull topology and closed-loop energy storage control of the boost circuit.

[0082] It should be noted that high-energy ignition applications require boosting the external 24-30V low-voltage DC power supply to several hundred volts in a very short time (usually within a few milliseconds between two ignitions) and precisely controlling the charging voltage of the energy storage capacitor to ensure that the energy released by each ignition is consistent.

[0083] refer to Figure 4 , Figure 5 , Figure 6 This embodiment details the specific structure and energy storage control process of the boost circuit. The boost circuit employs a push-pull DC-DC converter topology; see reference... Figure 5The specific circuit includes an external power input (Ui), a push-pull transformer (T), two switching transistors (K1, K2), and a rectifier filter network.

[0084] The primary winding of the push-pull transformer T has a center tap, which is directly connected to the positive terminal of the 24-30V external power supply Ui. The primary winding is divided into two symmetrical halves (N1 and N2 turns) by the center tap. The outer ends of these two halves are connected to the first switching transistor K1 and the second switching transistor K2, respectively. Switches K1 and K2 are N-channel power MOSFETs, with their sources connected to the negative terminal (ground) of the power supply. The secondary winding of the push-pull transformer T also has a center tap and is divided into two symmetrical halves (N31 and N32 turns). The center tap of the secondary winding is connected to the high-voltage reference ground of the system, and the two ends of the secondary winding are connected to the anodes of the first rectifier diode D1 and the second rectifier diode D2, respectively. The cathodes of D1 and D2 are connected together to form a full-wave rectified output, which is then connected in series with a filter inductor L and finally to the positive terminal of the energy storage capacitor C.

[0085] refer to Figure 4 and Figure 6 The boost circuit operates under strict closed-loop control by the microprocessor (CPU, using STM32F407). The microprocessor's internal PWM controller generates two complementary pulse width modulation (PWM) signals with a 180-degree phase difference and dead time, which control the alternating conduction of transistors K1 and K2 via the switching transistor drive circuit. When K1 is on, current flows through the primary winding N1; when K2 is on, current flows through the primary winding N2. The alternating primary current generates alternating magnetic flux in the core of transformer T, inducing high voltage in the secondary winding. After full-wave rectification by D1 and D2 and filtering by inductor L, the high voltage charges the energy storage capacitor C.

[0086] To achieve precise energy control, the system is equipped with an isolated voltage conversion circuit (i.e., a voltage sampling unit). The isolated voltage conversion circuit acquires the high voltage output (Uo) across the energy storage capacitor C in real time, linearly steps it down, and performs optoelectronic or magnetic isolation before converting it into a low-voltage analog signal (e.g., 0-3.3V) that can be safely read by the microprocessor analog-to-digital converter.

[0087] The microprocessor calculates the corresponding preset voltage threshold based on the target ignition energy. During charging, the microprocessor reads the real-time voltage value fed back from the isolation feedback at an extremely high frequency. When the voltage at the energy storage capacitor terminal is detected to reach the preset voltage threshold, the microprocessor immediately blocks the PWM signals output to K1 and K2, the transformer stops working, the energy storage capacitor completes charging and maintains high voltage, waiting for the ignition moment.

[0088] Based on the above scheme, a single push-pull transformer with a center tap and a full-wave rectifier topology are adopted. The circuit structure is compact, and the bidirectional magnetization utilization of the transformer core is high, making it very suitable for automotive / airborne applications with 24V low-voltage input and medium to high-power output. Combined with the high-frequency PWM control and isolated voltage real-time feedback loop of the STM32F407, the system can complete the rapid and precise energy storage of large amounts of energy (≥500mJ) within the extremely short interval of the ignition cycle, while avoiding interference from the high-voltage side to the low-voltage control side.

[0089] Example 7: This embodiment provides a detailed description of the adaptive control of the operating conditions for maintaining the pulse sequence.

[0090] It should be noted that gas generator sets experience changes in operating conditions such as sudden load changes and speed fluctuations during actual operation. If the parameters for maintaining the pulse sequence remain fixed, the spark duration may be insufficient under high load or low speed conditions, while energy will be wasted under light load or high speed conditions.

[0091] refer to Figure 1 The microprocessor connects to the engine control unit via a communication interface. The communication interface uses a controller area network bus interface, and the microprocessor periodically reads the engine's current speed and load data from the engine control unit according to a preset communication protocol.

[0092] A pulse parameter mapping table is pre-stored in the non-volatile memory within the microprocessor. This pulse parameter mapping table can be a two-dimensional lookup table, with engine speed as the row index (in this embodiment, it includes four speeds: 600, 900, 1200, and 1500 RPM) and engine load percentage as the column index (in this embodiment, it includes four speeds: 25%, 50%, 75%, and 100%). Each cell in the table stores two parameter values: the target number of pulses and the target duty cycle for the corresponding operating condition. The values ​​in the pulse parameter mapping table are determined through engine bench calibration tests and pre-programmed into the microprocessor's non-volatile memory.

[0093] Example of a pulse parameter mapping table (each cell in the table is formatted as: number of target pulses / target duty cycle): In each ignition cycle, after the microprocessor confirms breakdown and terminates the initial pulse, before preparing to output the sustain pulse sequence, the microprocessor reads the most recently acquired current engine speed and current load values ​​from the communication interface. The microprocessor searches the pulse parameter map table for the row and column index closest to the current operating condition, and reads the target pulse count and target duty cycle from the corresponding cell. If the current engine speed or load is between adjacent indices in the map table (e.g., the current engine speed is 1050 rpm, between 900 and 1200), the microprocessor uses linear interpolation to calculate the corresponding target pulse count and target duty cycle from the data in the adjacent cells.

[0094] The microprocessor controls the discharge switch to sequentially output each pulse in the sustaining pulse sequence according to the target pulse count and target duty cycle obtained from the query. During the conduction period of each sustaining pulse, the remaining charge in the energy storage capacitor discharges again to the primary winding, sustaining the arc in the spark plug gap in the secondary winding, thus maintaining the spark's combustion. During the turn-off period of each sustaining pulse, the residual current in the primary winding decays through the freewheeling circuit. (Reference) Figure 3 During the sustain pulse sequence region, the primary side current rises to near the preset sustain current threshold during each sustain pulse conduction period and decays during the turn-off period, forming periodic fluctuations.

[0095] For example, when the engine speed is currently 600 rpm and the load is 100%, the microprocessor queries the mapping table and finds that the target number of pulses is 6 and the target duty cycle is 75%, and outputs 6 sustain pulses with a larger duty cycle to provide a longer spark duration. When the engine speed increases to 1500 rpm and the load decreases to 25%, the microprocessor queries the mapping table and finds that the target number of pulses is 2 and the target duty cycle is 45%, and outputs only 2 sustain pulses with a smaller duty cycle.

[0096] For standby generator sets operating under relatively stable conditions, the communication interface and real-time operating parameter acquisition function can be omitted. A pre-calibrated fixed number of pulses (e.g., a fixed output of 5 pulses with a 60% duty cycle) can be used to maintain the spark. This simplified approach reduces system complexity and cost while still ensuring basic ignition reliability under stable operating conditions.

[0097] Based on the above scheme, by combining a pre-calibrated pulse parameter mapping table with real-time acquired operating parameters, the sustain pulse sequence is automatically adjusted to adapt to changes in engine operating conditions. Under low-speed, heavy-load conditions, more sustain pulses with a larger duty cycle are output to prolong spark duration and ensure reliable ignition; under high-speed, light-load conditions, sustain pulse output is reduced to decrease energy consumption and spark plug electrode wear. A linear interpolation method ensures a smooth transition of sustain pulse parameters when operating conditions change continuously, avoiding ignition quality fluctuations caused by discrete jumps.

[0098] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An ignition control method suitable for high-energy scenarios, characterized in that, include: The system receives signals from the crankshaft timing disk sensor, determines the ignition timing of each cylinder based on the received signals, and controls the boost circuit to charge the energy storage capacitor to a preset voltage threshold before the ignition timing arrives. When the ignition moment arrives, the discharge switch is turned on to discharge the energy storage capacitor to the primary winding of the ignition coil, and an initial pulse is output. During the initial pulse output, the primary side current waveform is acquired in real time at a preset high-frequency sampling rate by the current sampling unit, and the slope of the change of the primary side current is calculated in real time. Real-time monitoring of the abrupt change characteristics of the slope: When the primary current is detected to drop momentarily during its rise or oscillation, and the slope changes from a positive value to a negative value and then returns to a positive value, it is determined that the spark plug gap on the secondary side of the ignition coil has been broken down. After determining that the spark plug gap has been broken down, the discharge switch is turned off to end the initial pulse, and a sustaining pulse sequence is entered after a preset interval. The sustaining pulse sequence maintains the continuous combustion of the spark by repeatedly turning on the discharge switch to discharge the energy storage capacitor to the primary winding. The number of pulses and the duty cycle in the sustaining pulse sequence are dynamically adjusted according to the current operating parameters of the engine.

2. The ignition control method for high-energy scenarios according to claim 1, characterized in that, If the first abrupt change feature is not detected during the initial pulse output, the slope of change continues to be monitored. When the slope of the change is detected to continue to increase and exceed the preset magnetic saturation warning slope threshold, it is determined that the iron core of the ignition coil has entered a magnetic saturation state, generating a second abrupt change characteristic. In response to the second mutation feature, the discharge switch is forcibly shut off and the current ignition window is terminated.

3. The ignition control method for high-energy scenarios according to claim 2, characterized in that, It also includes the step of identifying the electrical parameters of the ignition coil during the discharge initiation phase of the initial pulse: During the preset initial sampling period after the discharge switch is turned on, the primary inductance of the ignition coil is calculated based on the rising slope of the primary current waveform and the current terminal voltage of the energy storage capacitor. The primary resistance of the ignition coil is calculated based on the decay rate of the primary current waveform after reaching its peak and the primary inductance. Based on the primary inductance and the primary internal resistance, the magnetic saturation warning slope threshold and the preset interval time are set.

4. The ignition control method for high-energy scenarios according to claim 1, characterized in that, The number of pulses and duty cycle in the sustain pulse sequence are dynamically adjusted according to the engine's current operating parameters, specifically including: The current speed and current load of the engine are obtained as the current operating condition parameters; In a pre-stored pulse parameter mapping table, using the current rotational speed and the current load as indexes, the target pulse count and target duty cycle corresponding to the current operating condition parameters are retrieved. According to the target number of pulses and the target duty cycle, the discharge switch is controlled to output each pulse in the sustaining pulse sequence in sequence.

5. The ignition control method for high-energy scenarios according to claim 1, characterized in that, The preset high-frequency sampling rate is not less than 1MHz; the analog signal collected by the current sampling unit is amplified and filtered by the signal conditioning circuit and then input to the analog-to-digital converter input terminal of the microprocessor, and the low-pass filter cutoff frequency in the signal conditioning circuit is set to more than half of the preset high-frequency sampling rate.

6. The ignition control method for high-energy scenarios according to claim 2, characterized in that, Also includes: After each successful detection of the first mutation feature, the actual duration from the on-time of the current initial pulse to the detection of the first mutation feature is recorded; The average of the actual durations recorded in the most recent consecutive ignition cycles is used as the historical average duration of breakdown. In the next ignition cycle, if the duration of the initial pulse exceeds a preset multiple of the average duration of the breakdown history and the first and second mutation features are still not detected, it is determined that the current cylinder has misfired, the discharge switch is turned off and a misfire alarm signal is output.

7. The ignition control method for high-energy scenarios according to any one of claims 1-6, characterized in that, The total duration of a single ignition window does not exceed 500 microseconds, and the total energy released by the energy storage capacitor within the single ignition window is not less than 500 millijoules.

8. An ignition control system suitable for high-energy scenarios, characterized in that, include: A microprocessor, connected to a crankshaft timing disc sensor, is used to receive signals from the crankshaft timing disc sensor and determine the ignition timing of each cylinder. A boost circuit, connected to the microprocessor, is used to boost the external power supply voltage under the control of the microprocessor to charge the energy storage capacitor. A voltage sampling unit is connected between the energy storage capacitor and the microprocessor, and is used to collect the terminal voltage of the energy storage capacitor in real time and feed it back to the microprocessor. A discharge switch is connected between the energy storage capacitor and the primary winding of the ignition coil, and its on and off states are controlled by the microprocessor. A current sampling unit is connected in series in the discharge circuit of the primary winding to collect the primary current signal in real time at a preset high-frequency sampling rate and feed it back to the microprocessor. The microprocessor calculates the slope of the primary current signal in real time. When it detects a first abrupt change in the slope that indicates the spark plug gap has been broken down, it turns off the discharge switch to end the initial pulse and controls the discharge switch to be turned on multiple times after a preset interval to output a sustaining pulse sequence.

9. The ignition control system for high-energy scenarios according to claim 8, characterized in that, The boost circuit adopts a push-pull topology and includes a push-pull transformer, a first switching transistor, a second switching transistor, and a rectifier and filter circuit. The primary winding of the push-pull transformer has a center tap, which is connected to the external power supply. The two ends of the primary winding are respectively connected to the first switch and the second switch. The secondary winding of the push-pull transformer has a center tap, which is connected to the reference ground of the primary side discharge circuit. The two ends of the secondary winding are respectively connected to the anodes of the first rectifier diode and the second rectifier diode. The cathodes of the first rectifier diode and the second rectifier diode are connected together and then connected to the energy storage capacitor through a filter inductor. The voltage sampling unit includes an isolated voltage conversion circuit. The input terminal of the isolated voltage conversion circuit collects the high voltage output of the energy storage capacitor, and its output terminal feeds back the stepped-down and isolated voltage signal to the analog-to-digital conversion input terminal of the microprocessor. The microprocessor adjusts the pulse width modulation signal output to the first switch and the second switch accordingly.

10. The ignition control system for high-energy scenarios according to claim 8, characterized in that, The current sampling unit includes a sampling resistor and a signal conditioning circuit; The sampling resistor is connected in series between the low-potential end of the primary winding and the reference ground; The signal conditioning circuit is connected between the sampling resistor and the analog-to-digital converter input terminal of the microprocessor, and is used to amplify and filter the voltage signal across the sampling resistor before inputting it into the microprocessor. The microprocessor is also connected to a communication interface, which is used to communicate with the engine control unit to obtain the current speed and current load of the engine. The microprocessor queries a pre-stored pulse parameter mapping table based on the obtained current speed and current load to obtain the target pulse number and target duty cycle, and controls the discharge switch to output the sustaining pulse sequence accordingly.

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