Knock signal analysis device, ignition control system, and knock signal analysis method

Abstract

The embodiment of the present application relates to the field of automobile power technology, and discloses a knock signal analysis device, an ignition control system and a knock signal analysis method, the device comprises: a preprocessing module, which is used for collecting a knock sensor voltage signal in real time and preprocessing the knock sensor voltage signal to obtain a preprocessed knock sensor voltage signal; the knock sensor voltage signal comprises a plurality of single pulse signals; a main processor connected with the preprocessing module, which is used for analyzing the preprocessed knock sensor voltage signal to obtain a voltage characteristic parameter; comparing the voltage characteristic parameter with a corresponding dynamic parameter threshold to obtain a knock intensity corresponding to the knock sensor voltage signal; an output module connected with the main processor, which is used for outputting a knock intensity signal according to the knock intensity; and a power stabilizing module, which is used for providing a stable power signal. The embodiment of the present application can effectively improve the accuracy of ignition control.

Description

Technical Field

[0001] This invention relates to the field of automotive internal combustion engine cylinder detection technology, specifically to a knock signal analysis device, an ignition control system, and a knock signal analysis method. Background Technology

[0002] Since the intensity of engine knock depends on the amplitude and duration of the knock sensor's output signal voltage, the shaped square wave signal is integrated to calculate the knock energy generated by the knock sensor. This energy is then compared with stored knock maps measured at different engine speeds to determine if knock of a certain intensity has occurred. When the integrated value exceeds the comparison threshold voltage, the comparator outputs a high level, indicating that knock has occurred. The ECU immediately issues a command to retard the ignition timing, typically by 0.2 to 1.5 crankshaft angles each time, until the knock is eliminated. When the integrated value is below the comparison reference voltage, the comparator outputs a low level, indicating that the knock has been eliminated. The ECU then increments the ignition timing by a certain amount until knock occurs again.

[0003] The intensity of knock is reflected in the bandwidth and voltage value of the detected square wave signal. Knock sensors are placed at different locations in the engine block or cylinder. When vibration or knocking occurs, it generates a small voltage peak; the greater the knocking or vibration, the larger the main peak value generated by the knock sensor. A certain high frequency indicates knocking or knocking, and the knock sensor is designed to measure a frequency range of 5-15kHz. Engine knocking generates pressure waves with a frequency of 1-10kHz. The pressure waves are transmitted to the cylinder block, causing the metal particles to vibrate and accelerate. The accelerometer knock sensor detects the intensity of knock pressure by measuring the vibration acceleration on the cylinder block surface. Premature ignition timing is a major cause of knocking. Because the engine is required to produce maximum power, to avoid power loss and knocking, current technology involves installing a knock sensor on the engine block side. This sensor detects knocking within the internal combustion engine and transmits a signal to the vehicle's ECU, causing the electronic control unit to automatically adjust the ignition timing.

[0004] When knocking occurs in an internal combustion engine, the high-temperature, high-pressure gases produced by combustion in the cylinder cause an imbalance in the piston's vertical movement, leading to engine vibration and adverse effects. Sensors detect and analyze the engine's mechanical vibration signals and send the received signals to a knock sensor module. This module analyzes the received signals to determine if knocking has occurred and then sends a signal to the electronic control system.

[0005] In practical applications, knock sensors are easily misinterpreted by external interference when receiving mechanical vibration signals, leading to incorrect information being transmitted to the vehicle's ECU. Therefore, knock sensor modules have emerged as a medium connecting the sensor and the ECU. A car engine uses a spark plug to ignite the air-fuel mixture, allowing the flame to propagate and burn within the mixture. If the ignition timing is too early or the fuel quality is poor, when the pressure abnormally increases during the flame's propagation, some parts of the air-fuel mixture may ignite before the flame reaches them, causing a momentary burst of combustion. The resulting gas shock wave impacts the cylinder walls, producing a metallic knocking sound. This phenomenon, identified by a microcontroller as the knock signal intensity, is called knocking. The main hazards caused by knocking are noise and vibration. Vibration can potentially damage the engine, especially under heavy load conditions.

[0006] Misjudgments and interference signals can both cause abnormal operation of the ignition module, making it unable to correctly determine the internal combustion status of gasoline in the engine. This leads to errors in the control logic of the ignition control module, which may result in the following adverse phenomena: The ignition control module has stopped working, and the car cannot start. This causes the control module to misjudge the cylinder, resulting in ignition in the wrong cylinder and ultimately the car not working. Incorrect ignition timing can lead to ignition failure, incomplete fuel combustion, or knocking, affecting vehicle power stability and hindering the reduction of vehicle exhaust emissions. Summary of the Invention

[0007] In view of the above problems, embodiments of the present invention provide a detonation signal analysis system and method to solve the problem of inaccurate detonation analysis leading to abnormal ignition control in the prior art.

[0008] According to one aspect of the present invention, a detonation signal analysis system is provided, the system comprising: The preprocessing module, connected to the detonation sensor, is used to acquire the detonation sensor voltage signal in real time and preprocess the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single pulse signals; The main processor, connected to the preprocessing module, is used to analyze the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; and to obtain the detonation intensity corresponding to the detonation sensor voltage signal by comparing the voltage characteristic parameters with the corresponding dynamic parameter thresholds; the voltage characteristic parameters include the peak and trough values ​​of each effective single pulse signal and the pulse width of the effective single pulse signal; The output module, connected to the main processor, is used to output a detonation intensity signal according to the detonation intensity. A power supply regulator module is used to provide a stable power signal.

[0009] In one alternative embodiment, the preprocessing module includes: The input signal protection unit is used to protect the original knock sensor voltage signal and suppress spike interference signals. The filtering unit is used to filter out high-frequency electromagnetic interference noise and low-frequency noise in the knock sensor voltage signal and extract the filtered knock sensor voltage signal. A reference voltage generation unit is used to provide a stable reference voltage; The operational amplifier unit is used to compare the filtered knock sensor voltage signal with the reference voltage and output the preprocessed knock sensor voltage signal.

[0010] In one alternative embodiment, the reference voltage generation unit includes an external reference voltage power supply and a voltage divider network; the operational amplifier unit includes an operational amplifier. The external reference voltage power supply is connected to the voltage divider network and the first input terminal of the operational amplifier, respectively; the output terminal of the filter unit is connected to the second input terminal of the operational amplifier.

[0011] In one alternative embodiment, the power module includes a power input protection unit, a power input filtering unit, and a voltage regulation output unit. Among them, the power input protection unit is used to filter out surges in the vehicle's power supply and to regulate the voltage of the input vehicle power supply. The power input filtering unit is used to filter out high-frequency ripples and low-frequency noise from the automotive power supply to obtain a filtered automotive power supply. The voltage regulator output unit is used to regulate the filtered automotive power supply and output a stable automotive power signal.

[0012] In one alternative approach, the preprocessed knock sensor voltage signal is analyzed to obtain voltage characteristic parameters, including: Obtain the current sampled value of the single-pulse signal; Compare the current sampled value with the previous sampled value. If the current sampled value is less than the previous sampled value, then update the previous sampled value into the peak array. Compare the current sampled value with the previous sampled value. If the current sampled value is greater than the previous sampled value, then update the previous sampled value to the valley array. The peak value and trough value of the single pulse signal are determined based on the peak array and the trough array. Based on the peak value and the trough value, based on the peak value and the trough value of the single pulse signal, and the upper voltage limit and the lower voltage limit, the effective single pulse signal in the knock sensor voltage signal is determined; Based on the peak and trough values ​​of the effective single pulse signals, the peak and trough values ​​of each effective single pulse signal, the pulse width of the effective single pulse signal, the number of peaks in the knock sensor voltage signal, and the average peak signal value are determined to obtain the voltage characteristic parameters; wherein, the pulse width of the effective single pulse signal is determined based on the time interval between adjacent effective single pulse signals and the signal duration of the effective single pulse signal.

[0013] In one alternative approach, the dynamic parameter threshold includes a dynamic voltage amplitude threshold; the output decision unit is specifically used for: Calculate the average time interval based on the time interval between adjacent valid single pulse signals; The dynamic average time interval threshold is determined based on the engine operating parameters; the engine operating parameters include engine speed. The detonation intensity of the detonation sensor voltage signal is determined by comparing the voltage characteristic parameters with the corresponding dynamic voltage amplitude threshold. The detonation intensity signal is output based on the detonation intensity.

[0014] In one alternative approach, the dynamic voltage amplitude threshold is determined as follows: Based on the engine's operating parameters, obtain the corresponding average reference peak value; The dynamic voltage amplitude threshold y is calculated based on the average reference peak value and the following formula: y = kww+t0; Where w is the average reference peak value, t0 represents the length of an effective single pulse signal, and k is a constant coefficient.

[0015] In one alternative embodiment, the output decision unit includes a first transistor, a positive power supply terminal connected to the emitter of the first transistor, the base of the first transistor connected to the output terminal of the detonation signal analysis unit via a fourth resistor, the collector of the first transistor connected to the decision signal output terminal via a fifth resistor, and the decision signal output terminal connected to a pull-up resistor and a pull-down resistor respectively.

[0016] According to another aspect of the present invention, an ignition control system is provided, the system including an electronic control unit and the aforementioned knock signal analysis device; The detonation signal analysis device outputs the decision results to the electronic control unit; The electronic control unit adjusts the ignition signal based on the decision result.

[0017] According to another aspect of the present invention, a method for analyzing detonation signals is provided, comprising: The preprocessing module acquires the detonation sensor voltage signal in real time and preprocesses the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single pulse signals; The main processor analyzes the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; based on the comparison of the voltage characteristic parameters with the corresponding dynamic parameter threshold, the detonation intensity corresponding to the detonation sensor voltage signal is obtained; the voltage characteristic parameters include the peak and trough values ​​of each effective single pulse signal and the pulse width of the effective single pulse signal; The output module outputs a detonation intensity signal based on the detonation intensity.

[0018] In one alternative embodiment, the preprocessing module includes an input signal protection unit, a filtering unit, a reference voltage generation unit, and an operational amplifier unit. The input signal protection unit protects the original knock sensor voltage signal collected from the input and suppresses spike interference signals. The filtering unit filters out high-frequency electromagnetic interference noise and low-frequency noise from the knock sensor voltage signal and extracts the filtered knock sensor voltage signal. The reference voltage generation unit provides a stable reference voltage; The operational amplifier unit compares the filtered knock sensor voltage signal with the reference voltage and outputs the preprocessed knock sensor voltage signal.

[0019] This invention embodiment uses a preprocessing module connected to a knock sensor to acquire the knock sensor voltage signal in real time and preprocess it to obtain a preprocessed knock sensor voltage signal. The knock sensor voltage signal includes multiple single-pulse signals. A main processor, connected to the preprocessing module, analyzes the preprocessed knock sensor voltage signal to obtain voltage characteristic parameters. The knock intensity corresponding to the knock sensor voltage signal is obtained by comparing the voltage characteristic parameters with corresponding dynamic parameter thresholds. The voltage characteristic parameters include the peak and trough values ​​of each effective single-pulse signal and the pulse width of the effective single-pulse signal. An output module, connected to the main processor, outputs a knock intensity signal based on the knock intensity. A power supply regulator module provides a stable power signal. This invention embodiment determines the accurate knock intensity by determining the dynamic parameter threshold based on the engine speed, which greatly improves the timing of the ignition control module, ensures effective and stable ignition of the ignition coil, thereby guaranteeing vehicle power stability and reducing exhaust emissions.

[0020] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0021] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of the detonation signal analysis device provided in an embodiment of the present invention is shown; Figure 2 A schematic diagram of the circuit structure of a detonation signal analysis device provided in another embodiment of the present invention is shown; Figure 3 A schematic diagram of the morphology of the detonation signal in the detonation signal analysis device provided in an embodiment of the present invention is shown; Figure 4 A schematic flowchart of the detonation signal analysis method provided in an embodiment of the present invention is shown. Detailed Implementation

[0022] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0023] Modern engine knock control systems use knock sensors to detect knock intensity. Before knock occurs, the microcomputer automatically reduces the ignition advance angle, keeping the ignition timing near the knock boundary curve, thereby increasing engine power and reducing fuel consumption. Since the intensity of engine knock depends on the amplitude and pulse width of the knock sensor's output signal, such as a square wave voltage, the knock energy generated by the knock sensor is calculated by integrating the shaped square wave signal. This invention utilizes the voltage amplitude and pulse width of the acquired input signal square wave, along with the intensity identified by the ignition control module, to determine whether the ignition module is functioning correctly within the set maximum allowable intensity range.

[0024] Figure 1 A schematic diagram of the detonation signal analysis device provided in an embodiment of the present invention is shown. Figure 1 As shown, the device 100 includes the following units: The preprocessing module 110 is connected to the detonation sensor and is used to acquire the detonation sensor voltage signal in real time and preprocess the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single pulse signals. The main processor 120, connected to the preprocessing module 110, is used to analyze the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; and to obtain the detonation intensity corresponding to the detonation sensor voltage signal by comparing the voltage characteristic parameters with the corresponding dynamic parameter thresholds; the voltage characteristic parameters include the peak value and trough value of each effective single pulse signal and the pulse width of the effective single pulse signal; Output module 130, connected to the main processor 120, is used to output a detonation intensity signal according to the detonation intensity; The power supply regulator module 140 is used to provide a stable power signal to the detonation signal analysis device 100.

[0025] Among them, such as Figure 2 As shown, the preprocessing module 110 includes an input signal protection unit, a filtering unit, a reference voltage generation unit, and an operational amplifier unit. The input signal protection unit protects the acquired raw detonation sensor voltage signal and suppresses spike interference signals. The filtering unit filters out high-frequency electromagnetic interference noise and low-frequency noise from the detonation sensor voltage signal and extracts the filtered detonation sensor voltage signal. The reference voltage generation unit provides a stable reference voltage. The operational amplifier unit compares the filtered detonation sensor voltage signal with the reference voltage and outputs the preprocessed detonation sensor voltage signal. Specifically, the preprocessing module 110 is an integrated processing unit for the protection, filtering, reference, and discrimination of detonation sensor signals. It is subdivided into four sub-units according to signal flow and function, each sub-unit corresponding to a specific role. Among them, the input signal protection unit is composed of a current-limiting resistor R19 connected in series at the IN terminal, used to provide front-end protection for the raw analog signal input from the detonation sensor. IN is the analog signal output by the detonation sensor. The current-limiting resistor R19 is used to suppress signal overcurrent and prevent transient voltage or current from the sensor output from damaging the subsequent circuit. At the same time, the impedance of the sensor and the subsequent circuit is matched to prevent signal attenuation and reflection during signal transmission and to ensure the integrity of the original signal.

[0026] The filtering unit includes a first capacitor C4, a second capacitor C5, a first resistor R21, a third capacitor C1, and a fourth capacitor C2, used to purify the noise of the knock signal. Specifically, the first capacitor C4 and the second capacitor C5 form a high-frequency filtering network to filter out high-frequency electromagnetic interference radiated from the engine wiring harness; the first resistor R21, the third capacitor C1, and the fourth capacitor C2 form a low-pass filtering network to eliminate low-frequency noise introduced by power supply ripple and mechanical vibration; finally, a clean and stable analog signal is output, providing a reliable input for subsequent comparison and discrimination.

[0027] The reference voltage generation unit includes a second resistor R23 and a third resistor R24, used to provide a stable comparison reference threshold. A precise 2.5V external reference voltage is generated through a resistor divider network composed of the second resistor R23 and the third resistor R24, serving as the "baseline" for the LM2904 to distinguish knock signals, ensuring the consistency and accuracy of signal amplitude comparison. The relationship between the second resistor R23 and the third resistor R24, the external reference voltage, and the input power supply can be expressed as follows: .in, This is the input power supply.

[0028] The operational amplifier unit includes an LM2904 operational amplifier for real-time, rapid detection of knock signals. The filtered analog knock signal is compared in real-time with a 2.5V reference voltage. When the signal amplitude exceeds the reference voltage, a high-level digital signal (OUT1) is immediately output. Leveraging the LM2904's typical 0.3μs response time, low-latency capture of the knock event is achieved, while direct digital signal output simplifies the MCU's read logic. The use of the LM2904 operational amplifier ensures fast circuit response, meeting engine real-time requirements; the direct digital signal output from the LM2904 simplifies the MCU's read logic and system design.

[0029] The preprocessing module 110 performs anti-interference and filtering operations on the signal input from the knock sensor, ensuring the comparator receives a relatively clean and stable analog signal. The LM2904 operational amplifier plays a signal discrimination role in this circuit, comparing the amplitude of the received analog signal with a reference voltage. Specifically, the LM2904VQPWRQ1 is an automotive-grade dual-channel operational amplifier. This circuit amplifies the IN signal output from the knock sensor with unity gain. Because the LM2904 series op-amps have a large unity-gain bandwidth (1.2MHz), this circuit operates without causing severe signal distortion, exhibiting high stability, lower offset voltage, and lower quiescent current. OUT1 is the knock signal processed by the ADC. This unity-gain amplifier acts as a buffer, ensuring the signal is completely preserved during transmission, while also providing impedance matching and signal isolation. When the signal amplitude exceeds the reference voltage value, the comparator immediately outputs a high-level digital signal, which serves as the ADC signal input to the MCU as an indicator of knock detection. The MCU uses this high-level signal to control the ignition timing to prevent knocking inside the cylinder block.

[0030] The main processor 120 is connected to the preprocessing module 110. After obtaining the preprocessed digital signal, it analyzes the preprocessed knock sensor voltage signal to obtain voltage characteristic parameters. The main processor 120 is an S9S08SG16E1WTGR chip. Based on the preprocessed digital signal, it filters valid signals and extracts features. The circuit of the main processor 120 is built around the S9S08SG16E1WTGR chip. The fifth capacitor C7 serves the following purposes: 1. Providing delay control for the reset signal; 2. Ensuring the microcontroller ends the reset state only after the power supply stabilizes; 3. Filtering out power supply noise and interference. The fourth resistor R4 acts as a pull-up resistor for the RESET programming interface. The fourth resistor R4 and the fifth capacitor C7 form an RC circuit. The RC charging and discharging process controls the reset time, ensuring the reset signal duration meets the microcontroller's requirements and preventing accidental resets. During a high-level reset, the capacitor charges, causing the RESET pin voltage to gradually decrease. The reset must be completed before the voltage drops below the reset threshold. The fifth resistor, R3, is a surge protector. Its main function is to suppress surge current, protect the LDO from overvoltage surges, and ensure stable output voltage. The sixth capacitor, C18, filters out low-frequency fluctuations, stabilizes the voltage during the programming process, and prevents data errors or device damage caused by voltage instability during programming. The seventh capacitor, C17, suppresses high-frequency noise. The eighth capacitor, C16, decouples the power supply and smooths power supply voltage fluctuations through energy storage and release, reducing voltage instability caused by load changes or external interference. The fifth resistor, R27, the sixth resistor, R28, and the seventh resistor, R29, are a set of marking resistors; the presence or absence of these resistors on different pins indicates different programming functions. Pins 15 and 16 of the S9S08SG16E1WTGR are the input terminals for analyzing the knock signal, and pin 13, PTA3, is the output knock intensity signal.

[0031] In this embodiment of the invention, the main processor 120 is also connected to the AD sampling circuit 150. During analysis, the main processor 120 requires AD sampling to obtain the voltage drop of the sampling current, and the AD sampling circuit 150 acquires the external voltage. Because the main processor 120 has a minimum operating voltage, it can acquire the external voltage change via pin 9. The AD sampling circuit 150 converts the input power signal into a voltage signal that can be processed by the main processor 120 through the eighth resistor R34 and the ninth resistor R7. Noise is filtered out through the ninth capacitor C19 and the tenth resistor R8 to avoid interfering with the sampling accuracy.

[0032] Specifically, the main processor 120 acquires the current sampled value of the single-pulse signal; compares the current sampled value with the previous sampled value; if the current sampled value is less than the previous sampled value, the previous sampled value is updated in the peak array; compares the current sampled value with the previous sampled value; if the current sampled value is greater than the previous sampled value, the previous sampled value is updated in the trough array; determines the peak value and trough value of the single-pulse signal based on the peak array and the trough array; determines the effective single-pulse signal in the knock sensor voltage signal based on the peak value and the trough value, the peak value and the trough value of the single-pulse signal, the upper voltage limit and the lower voltage limit; and determines the peak value and trough value of each effective single-pulse signal, the time interval between adjacent effective single-pulse signals, the signal duration of the effective single-pulse signal, the number of peaks in the knock sensor voltage signal, and the average peak signal value based on the peak value and trough value of the effective single-pulse signal, to obtain the voltage characteristic parameters. The voltage characteristic parameters include the peak value and trough value of each effective single-pulse signal and the pulse width of the effective single-pulse signal.

[0033] Among them, the effective single pulse signal screening is carried out by comparing the peak value and trough value of each single pulse signal with the preset upper and lower voltage limits, thereby filtering out invalid pulses caused by noise, such as interference pulses with too small amplitude.

[0034] Next, feature parameters are extracted. For each valid single-pulse signal, its peak value (the highest voltage point of the pulse), trough value (the lowest voltage point of the pulse), and signal duration are calculated. The signal duration is the time from pulse initiation to termination. The relationship between valid single-pulse signals is determined, and the time interval between adjacent valid single pulses (the time difference between the peak points of two pulses) is calculated. For the overall detonation voltage signal, the number of peaks and the average peak signal value are counted. The average peak signal value is the average of the peak values ​​of all valid single pulses; the number of peaks is the total number of valid single pulses. These voltage feature parameters are then compared with corresponding dynamic parameter thresholds to determine the detonation intensity signal corresponding to the detonation sensor voltage signal. The dynamic parameter threshold is determined based on the engine operating parameters corresponding to the detonation sensor voltage signal. In one implementation, the engine operating parameters include engine speed.

[0035] Specifically, such as Figure 3As shown, since the intensity of the detonation is directly related to the voltage amplitude of the pulse, the main processor 120 compares the voltage characteristic parameters with the corresponding dynamic voltage amplitude threshold to determine the detonation intensity of the detonation sensor voltage signal. This is achieved by comparing the current voltage amplitude with the dynamic voltage amplitude threshold; the more the peak value exceeds the threshold, the stronger the vibrational energy of the detonation and the higher the detonation intensity. The current voltage amplitude can be the peak value or average peak value of an effective single pulse; this embodiment of the invention does not impose specific limitations. In this embodiment, the intensity of the detonation signal can be divided into multiple levels according to preset levels.

[0036] The inventors of this application discovered that the normal interval of the knock pulse varies at different engine speeds; for example, the higher the engine speed, the shorter the knock pulse interval, and the knock intensity also varies. Therefore, this application sets the dynamic parameter threshold to be dynamic, rather than a fixed value. The main processor 120 of this embodiment also pre-establishes a mapping relationship between knock voltage intensity and engine operating conditions (e.g., real-time current engine speed), thereby identifying knock based on voltage characteristic parameters and retrieving the dynamic voltage amplitude threshold at the corresponding engine speed according to a preset operating condition-threshold mapping table. This threshold is the dynamic voltage amplitude threshold that the actual knock signal should have under the current operating conditions. This embodiment of the invention determines the dynamic voltage amplitude threshold in the following manner: Based on the current engine operating parameters, obtain the corresponding average reference peak value; The dynamic voltage amplitude threshold y is calculated based on the average reference peak value and the following formula: y = kww+t0; Where w is the average reference peak value, t0 represents the length of an effective single pulse signal, and k is a constant coefficient.

[0037] The above method can be used to establish a mapping relationship between knock voltage intensity and engine operating conditions, and obtain the dynamic voltage amplitude threshold.

[0038] In one embodiment of the present invention, the main processor 120 further determines the interference intensity of the knock sensor voltage signal based on the average time interval and the dynamic average time interval threshold. This is determined by comparing the current average time interval with the dynamic average time interval threshold: if the current average time interval is close to the dynamic average time interval threshold, it indicates a stable pulse interval, a high probability of a real knock, and low interference intensity; if the current average time interval deviates from the dynamic average time interval threshold, such as fluctuating length, it indicates random pulses, a high probability of electromagnetic interference or mechanical noise, and high interference intensity. The final decision is based on the knock intensity and the severity of the interference. If the knock intensity is high and the interference intensity is low, it is determined to be a real strong knock, and a signal requiring adjustment of the ignition advance angle is output. If the knock intensity is high but the interference intensity is also high, it is determined to be a false knock caused by interference, and no adjustment signal is output. If the knock intensity is low and the interference intensity is low, it is determined to be a minor knock, and a signal for a small adjustment is output. In this embodiment of the present invention, the main processor 120 also pre-establishes a mapping relationship between knock voltage intensity and engine operating conditions, thereby achieving dynamic anti-interference processing based on knock identification of voltage characteristic parameters. The process involves: calculating an average time interval based on the time interval between adjacent effective single-pulse signals; obtaining current engine operating parameters and determining a dynamic average time interval threshold based on these parameters; determining the interference intensity of the knock sensor voltage signal based on the average time interval and the dynamic average time interval threshold; determining the knock intensity of the knock sensor voltage signal by comparing the voltage characteristic parameters with the corresponding dynamic voltage amplitude threshold; and outputting a decision result based on the knock intensity and interference intensity. In this embodiment, a mapping relationship between knock voltage intensity and engine operating conditions is pre-established, thereby achieving dynamic anti-interference processing based on knock identification using voltage characteristic parameters. Specifically, the dynamic average time interval threshold is determined as follows: based on the current engine operating parameters, the corresponding average reference peak value, the average reference value of the interval between peak values, and the corresponding correction coefficient are obtained; the dynamic average time interval threshold ΔT is calculated using the following formula: △T= w*w(1+△t*△t / 32) + f(w); Where w is the average reference peak value, Δt is the average reference value between peak values, and f(w) is the lookup table correction function; the lookup table correction function is determined based on a constant table based on the average reference peak value.

[0039] Output unit 130 includes a first transistor Q1, with its emitter grounded. The base of transistor Q1 is connected to the output terminal of the detonation signal analysis unit via resistor R10, and the collector is connected to the detonation intensity signal output terminal via resistor R11. Specifically, the detonation intensity signal comes from the MCU processor and is input to the base of Q1 via resistor R26 to control the on / off state of Q1, thereby changing the level of the output terminal IGF. When the decision result is high: the base potential of Q1 is higher than the emitter (grounded), Q1 is turned on, the collector is pulled to ground potential, and the IGF terminal outputs a low level. When the decision result is low: the base potential of Q1 is equal to the emitter potential, Q1 is turned off, the collector is pulled to the power supply level via resistor R10, and the IGF terminal outputs a high level. Output unit 130 amplifies the weak control signal from the main controller 120 and outputs a stable detonation intensity signal (IGF). Q1 is an NPN transistor, used as a switching device to amplify the weak signal output by the MCU and enhance its driving capability. Resistors R9 and R10 are transistor bias resistors, used to control the on or off state of Q1, ensuring that the level and amplitude of the IGF signal meet the ECU's receiving requirements. IGF is the final output knock intensity signal, transmitted to the vehicle ECU for ignition control adjustment.

[0040] The power supply regulator module 140 provides a stable power signal. It includes the input power supply B+, a first diode D1 (SM4007PLHE3-P), surge protectors R1 and R2, filter capacitors C1 and C2, a second diode D2 (SMAJ33CAHE3-P), and a voltage regulator U1 (NCV4264-2CST50T3G). This power supply regulator module 140 provides a stable and safe automotive-grade power supply for the entire module. The first diode D1 is a reverse polarity protection diode to prevent damage to the circuit from reverse polarity; R1 / R2 are surge protectors to suppress transient high voltage or high current surges from the automotive power supply; C1 / C2 are filter capacitors to smooth power supply voltage fluctuations and eliminate power supply ripple; D2 is a Zener diode to limit the upper limit of the input voltage (33V) to prevent overvoltage damage; U1 is an automotive-grade LDO regulator that converts the automotive B+ power supply (typically 12~24V) to a stable 5V (VCC) to power subsequent modules.

[0041] This invention embodiment uses a preprocessing module connected to a knock sensor to acquire the knock sensor voltage signal in real time and preprocess it to obtain a preprocessed knock sensor voltage signal. The knock sensor voltage signal includes multiple single-pulse signals. A main processor, connected to the preprocessing module, analyzes the preprocessed knock sensor voltage signal to obtain voltage characteristic parameters. The knock intensity corresponding to the knock sensor voltage signal is obtained by comparing the voltage characteristic parameters with corresponding dynamic parameter thresholds. The voltage characteristic parameters include the peak and trough values ​​of each effective single-pulse signal and the pulse width of the effective single-pulse signal. An output module, connected to the main processor, outputs a knock intensity signal based on the knock intensity. A power supply regulator module provides a stable power signal. This invention embodiment determines the accurate knock intensity by determining the dynamic parameter threshold based on the engine speed, which greatly improves the timing of the ignition control module, ensures effective and stable ignition of the ignition coil, thereby guaranteeing vehicle power stability and reducing exhaust emissions.

[0042] Figure 4 A flowchart of a knock signal analysis method provided in an embodiment of the present invention is shown, which is executed by an automotive engine system. Figure 4 As shown, the method includes the following steps: Step 110: The preprocessing module acquires the detonation sensor voltage signal in real time and preprocesses the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single-pulse signals; Step 120: The main processor analyzes the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; based on the voltage characteristic parameters and the corresponding dynamic parameter thresholds, the detonation intensity corresponding to the detonation sensor voltage signal is obtained; the voltage characteristic parameters include the peak and trough values ​​of each effective single pulse signal and the pulse width of the effective single pulse signal; Step 130: The output module outputs a detonation intensity signal based on the detonation intensity.

[0043] In one embodiment of the present invention, the preprocessing module includes an input signal protection unit, a filtering unit, a reference voltage generation unit, and an operational amplifier unit. The input signal protection unit protects the acquired raw detonation sensor voltage signal and suppresses spike interference signals; the filtering unit filters out high-frequency electromagnetic interference noise and low-frequency noise from the detonation sensor voltage signal, extracting the filtered detonation sensor voltage signal; the reference voltage generation unit provides a stable reference voltage; and the operational amplifier unit compares the filtered detonation sensor voltage signal with the reference voltage and outputs the preprocessed detonation sensor voltage signal.

[0044] In this embodiment of the invention, the specific execution steps are generally consistent with the specific working process of each unit of the aforementioned device, and will not be described in detail here.

[0045] According to another aspect of the present invention, an ignition control system is provided, the system including an electronic control unit and the aforementioned knock signal analysis device; The detonation signal analysis device outputs the decision results to the electronic control unit; The electronic control unit adjusts the ignition signal based on the decision result.

[0046] This invention employs a detonation signal acquisition unit to acquire detonation sensor voltage signals in real time. These signals include multiple single-pulse signals. A detonation signal analysis unit analyzes the voltage characteristic parameters of the detonation sensor voltage signals. An output decision unit compares the voltage characteristic parameters with dynamic parameter thresholds to determine the detonation intensity and interference intensity of the detonation sensor voltage signals, and outputs the decision result. This effectively eliminates interference signals and accurately analyzes the detonation situation, resulting in more accurate and stable ignition control. The dynamic anti-interference processing algorithm in this invention improves detection reliability and response speed in complex electromagnetic environments.

[0047] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system, or other device. Various general-purpose systems can also be used in conjunction with the teachings herein. The required structure for constructing such systems is apparent from the above description. Furthermore, the embodiments of the present invention are not directed to any particular programming language. It should be understood that the content of the invention described herein can be implemented using various programming languages, and the above description of specific languages ​​is for the purpose of disclosing the best mode of implementation of the invention.

[0048] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0049] Similarly, it should be understood that, in order to streamline the invention and aid in understanding one or more of the various aspects of the invention, features of the embodiments of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the invention. However, this disclosure should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim.

[0050] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0051] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A detonation signal analysis device, characterized in that, The device includes: The preprocessing module, connected to the detonation sensor, is used to acquire the detonation sensor voltage signal in real time and preprocess the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single pulse signals; The main processor, connected to the preprocessing module, is used to analyze the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; and to obtain the detonation intensity corresponding to the detonation sensor voltage signal by comparing the voltage characteristic parameters with the corresponding dynamic parameter thresholds; the voltage characteristic parameters include the peak and trough values ​​of each effective single pulse signal and the pulse width of the effective single pulse signal; The output module, connected to the main processor, is used to output a detonation intensity signal according to the detonation intensity. A power supply regulator module is used to provide a stable power signal.

2. The apparatus according to claim 1, characterized in that, The preprocessing module includes: The input signal protection unit is used to protect the original knock sensor voltage signal and suppress spike interference signals. The filtering unit is used to filter out high-frequency electromagnetic interference noise and low-frequency noise in the knock sensor voltage signal and extract the filtered knock sensor voltage signal. A reference voltage generation unit is used to provide a stable reference voltage; The operational amplifier unit is used to compare the filtered knock sensor voltage signal with the reference voltage and output the preprocessed knock sensor voltage signal.

3. The apparatus according to claim 2, characterized in that, The reference voltage generation unit includes an external reference voltage power supply and a voltage divider network; the operational amplifier unit includes an operational amplifier. The external reference voltage power supply is connected to the voltage divider network and the first input terminal of the operational amplifier, respectively; the output terminal of the filter unit is connected to the second input terminal of the operational amplifier.

4. The apparatus according to claim 1, characterized in that, The power module includes a power input protection unit, a power input filtering unit, and a voltage regulation output unit; Among them, the power input protection unit is used to filter out surges in the vehicle's power supply and to regulate the voltage of the input vehicle power supply. The power input filtering unit is used to filter out high-frequency ripples and low-frequency noise from the automotive power supply to obtain a filtered automotive power supply. The voltage regulator output unit is used to regulate the filtered automotive power supply and output a stable automotive power signal.

5. The apparatus according to claim 1, characterized in that, Analyzing the preprocessed knock sensor voltage signal yields voltage characteristic parameters, including: Obtain the current sampled value of the single-pulse signal; Compare the current sampled value with the previous sampled value. If the current sampled value is less than the previous sampled value, then update the previous sampled value into the peak array. Compare the current sampled value with the previous sampled value. If the current sampled value is greater than the previous sampled value, then update the previous sampled value to the valley array. The peak value and trough value of the single pulse signal are determined based on the peak array and the trough array. Based on the peak value and the trough value, based on the peak value and the trough value of the single pulse signal, and the upper voltage limit and the lower voltage limit, the effective single pulse signal in the knock sensor voltage signal is determined; Based on the peak and trough values ​​of the effective single pulse signals, the peak and trough values ​​of each effective single pulse signal, the pulse width of the effective single pulse signal, the number of peaks in the knock sensor voltage signal, and the average peak signal value are determined to obtain the voltage characteristic parameters; wherein, the pulse width of the effective single pulse signal is determined based on the time interval between adjacent effective single pulse signals and the signal duration of the effective single pulse signal.

6. The apparatus according to claim 5, characterized in that, The dynamic parameter threshold includes a dynamic voltage amplitude threshold; the output decision unit is specifically used for: Calculate the average time interval based on the time interval between adjacent valid single pulse signals; The dynamic average time interval threshold is determined based on engine operating parameters; the engine operating parameters include engine speed. The detonation intensity of the detonation sensor voltage signal is determined by comparing the voltage characteristic parameters with the corresponding dynamic voltage amplitude threshold. The detonation intensity signal is output based on the detonation intensity.

7. The apparatus according to claim 6, characterized in that, The dynamic voltage amplitude threshold is determined in the following manner: Based on the engine's operating parameters, obtain the corresponding average reference peak value; The dynamic voltage amplitude threshold y is calculated based on the average reference peak value and the following formula: y = kww+t0; Where w is the average reference peak value, t0 represents the length of an effective single pulse signal, and k is a constant coefficient.

8. An ignition control system, characterized in that, The system includes an electronic control unit and a knock signal analysis device as described in any one of claims 1-7; The detonation signal analysis device outputs the decision results to the electronic control unit; The electronic control unit adjusts the ignition signal based on the decision result.

9. A method for analyzing detonation signals, characterized in that, The method includes: The preprocessing module acquires the detonation sensor voltage signal in real time and preprocesses the detonation sensor voltage signal to obtain the preprocessed detonation sensor voltage signal; the detonation sensor voltage signal includes multiple single pulse signals; The main processor analyzes the preprocessed detonation sensor voltage signal to obtain voltage characteristic parameters; based on the comparison of the voltage characteristic parameters with the corresponding dynamic parameter threshold, the detonation intensity corresponding to the detonation sensor voltage signal is obtained; the voltage characteristic parameters include the peak and trough values ​​of each effective single pulse signal and the pulse width of the effective single pulse signal; The output module outputs a detonation intensity signal based on the detonation intensity.

10. The method according to claim 9, characterized in that, The preprocessing module includes an input signal protection unit, a filtering unit, a reference voltage generation unit, and an operational amplifier unit. The input signal protection unit protects the original knock sensor voltage signal collected from the input and suppresses spike interference signals. The filtering unit filters out high-frequency electromagnetic interference noise and low-frequency noise from the knock sensor voltage signal and extracts the filtered knock sensor voltage signal. The reference voltage generation unit provides a stable reference voltage; The operational amplifier unit compares the filtered knock sensor voltage signal with the reference voltage and outputs the preprocessed knock sensor voltage signal.

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