Self-learning calibration method and device of turbine actuator and turbine actuator

Abstract

The invention relates to the technical field of turbine actuators, in particular to a self-learning calibration method and device of a turbine actuator and the turbine actuator. The method comprises the steps that real-time working condition information of an engine is obtained through a vehicle-mounted network signal; according to the obtained working condition information, the state of the engine is recognized; when the engine is in a power-on non-starting state or an idling state, the turbine actuator enters a self-learning mode, and learning of left and right limit positions is carried out; calculating a proportional conversion coefficient between the opening percentage of the turbine actuator and the operation step number of the motor or the angle of the output shaft; and according to the proportion conversion coefficient, the requested opening percentage of the engine ECU is converted into the control angle of the turbine actuator or the operation step number of the motor, the drive motor is controlled according to the cascade PID, the turbine actuator executes the request of the ECU, and a target opening execution response is made. Self-calibration of the turbine actuator is achieved, it is guaranteed that the turbine actuator obtains the accurate absolute opening value all the time, and therefore the equipment installation cost is reduced.

Description

Technical Field

[0001] This application relates to the technical field of turbine actuators, and specifically relates to a self-learning calibration method, device, and turbine actuator for a turbine actuator. Background Art

[0002] Turbine actuators play a crucial role in automotive engine systems. They are mainly responsible for controlling the exhaust gas opening, and by adjusting the turbine speed and boost pressure, they optimize the engine performance. The technological development of turbine actuators can be traced back to the 19th century, and then turbocharging technology was gradually applied to aircraft and tank engine systems. Nowadays, turbochargers are widely used in the automotive industry, enabling the engine to obtain greater power and torque with the same displacement, thus enhancing vehicle performance.

[0003] In the prior art, there are many problems in the calibration learning work of turbine actuators. On the one hand, when the turbine is first installed, replaced, or needs calibration, it is necessary to complete the calibration learning with the help of a dedicated turbine calibrator or a specified automotive diagnostic device. Only by successfully obtaining the absolute stroke can the turbine actuator correctly respond to the request instructions of the engine ECU, otherwise it cannot work properly. This undoubtedly increases the product cost and installation cost of the equipment, and also poses specific requirements for the supporting equipment, making the installation and maintenance processes complex and costly.

[0004] On the other hand, existing turbine actuators rely on motor drive to achieve the opening and holding of a specified opening, and rely on sensors or the motor itself to count steps to obtain the absolute angle. Under the traditional passive learning calibration strategy, the calibration frequency is low, usually only calibrated once during installation or replacement. However, during long-term operation, factors such as carbon deposition conditions, sensor accuracy degradation, and motor operation skipping steps will cause cumulative errors in the turbine actuator, resulting in inaccurate execution of the opening. This will not only reduce the vehicle's power performance, but also cause insufficient air-fuel ratio mixing and incomplete fuel combustion, thereby increasing carbon deposition and fuel consumption, accelerating engine wear, and ultimately affecting the service life of the vehicle. Summary of the Invention

[0005] Aiming at the problem that under the traditional passive learning calibration strategy, calibration is usually only performed once during installation or replacement, resulting in cumulative errors in the turbine actuator and inaccurate execution of the opening, the present invention provides a self-learning calibration method, device, and turbine actuator for a turbine actuator.

[0006] In the first aspect, the technical solution of the present invention provides a self-learning calibration method for a turbine actuator, including the following steps: Obtain the real-time operating conditions of the engine through the in-vehicle network signal, including engine speed, throttle pedal opening, and engine requested torque percentage; According to the obtained operating condition information, identify the state of the engine, including the power-on but not started state, the idle state, and the working state; When the engine is in the power-on but not started state or the idle state, the turbine actuator enters the self-learning mode to learn the left and right limit positions; According to the learned limit positions, calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle; Through the proportional conversion coefficient, convert the requested opening percentage of the engine ECU into the control angle of the turbine actuator or the number of motor running steps, and drive the motor according to the cascade PID control, so that the turbine actuator executes the request of the ECU and makes a target opening execution response.

[0007] As a further limitation of the technical solution of the present invention, the steps of identifying the state of the engine according to the obtained operating condition information include: Judge according to the obtained operating condition information; The engine is powered on, the speed is equal to zero, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the power-on but not started state; The engine is powered on, the speed is at the low idle speed, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the idle state; The engine is powered on, the speed is higher than the low idle speed and is in a fluctuating state, and both the throttle pedal opening and the engine requested torque percentage are greater than zero and are in a fluctuating state; it is determined that the engine is in the working state.

[0008] As a further limitation of the technical solution of the present invention, when the engine is in the power-on but not started state or the idle state, the steps of the turbine actuator entering the self-learning mode to learn the left and right limit positions include: When the engine is in the power-on but not started state or the idle state, judge whether the turbine actuator is in the state of not completing self-learning after power-on; If so, the turbine actuator enters the self-learning mode to learn the left and right limit positions, and completes the self-learning work before the engine enters the working state; If not, the turbine actuator enters the initialization mode, and the turbine actuator enters the steady-state working state.

[0009] As a further limitation of the technical solution of the present invention, the steps of the turbine actuator entering the self-learning mode to learn the left and right limit positions include: In the self-learning mode, drive the motor to rotate in the direction of closing the exhaust gas intake opening at a fixed speed, and judge whether the limit position is reached by the motor speed and the stall current; When the motor speed is less than the preset speed and the stall current is greater than the preset value, record the current limit position, and repeat the process to learn the limit position on the other side; If the turbine actuator is provided with an output shaft angle sensor, record the angle values reached at both limit positions; if the turbine actuator is not provided with an output shaft angle sensor, record the cumulative number of running steps of the motor from one limit position to the other limit position.

[0010] As a further limitation of the technical solution of the present invention, the steps of determining whether the limit position is reached by the motor speed and the stall current include: When the judgment condition is satisfied, it is considered that the limit position on one side is reached, and the learned motor position is recorded; the judgment condition is that the motor speed is less than the preset speed, the stall current is greater than the preset value, and the holding state accumulates to reach the first time threshold; If the judgment condition is not satisfied after exceeding the second time threshold, it is considered that the learning fails and enters the learning failure state.

[0011] As a further limitation of the technical solution of the present invention, the steps of calculating the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle according to the learned limit position include: When the recorded information is the angle values reached at both limit positions, calculate the proportional coefficient according to the output shaft angle and the opening percentage of the turbine actuator; When the recorded information is the cumulative number of running steps of the motor from one limit position to the other limit position, calculate the proportional coefficient according to the cumulative limit position, the number of motor running steps, and the opening percentage of the turbine actuator.

[0012] As a further limitation of the technical solution of the present invention, the method further includes: After the self-learning is completed, drive the turbine actuator to the default opening position required before the corresponding engine working state, and the turbine actuator enters the steady-state working state.

[0013] As a further limitation of the technical solution of the present invention, the cascade PID control includes an outer loop position PID control and an inner loop speed PID control. The outer loop is responsible for controlling the forward rotation, reverse rotation, and stop of the motor, and the inner loop is responsible for the specific speed regulation.

[0014] In a second aspect, the technical solution of the present invention further provides a self-learning calibration device for a turbine actuator, including a working condition information acquisition module, an engine state recognition module, a self-learning execution module, and a processing and control module; The working condition information acquisition module is used to obtain the real-time working condition information of the engine through the in-vehicle network signal, including the engine speed, the throttle pedal opening, and the engine requested torque percentage; The engine state recognition module is used to identify the state of the engine according to the obtained working condition information, including the power-on and not-started state, the idle state, and the working state; A self-learning execution module, which is used to enable the turbine actuator to enter the self-learning mode to learn the left and right limit positions when the engine is in the powered-on but not started state or the idle state; A processing and control module, which is used to calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle according to the learned limit positions; through the proportional conversion coefficient, convert the requested opening percentage of the engine ECU into the control angle or the number of motor running steps of the turbine actuator, and drive the motor according to the cascade PID control to make the turbine actuator execute the request of the ECU and make a target opening execution response.

[0015] As a further limitation of the technical solution of the present invention, an engine state recognition module judges according to the obtained working condition information; when the engine is powered on, the rotational speed is zero, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the powered-on but not started state; when the engine is powered on, the rotational speed is at the low idle speed, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the idle state; when the engine is powered on, the rotational speed is higher than the low idle speed and is in a fluctuating state, and both the throttle pedal opening and the engine requested torque percentage are greater than zero and are in a fluctuating state; it is determined that the engine is in the working state.

[0016] As a further limitation of the technical solution of the present invention, a self-learning execution module is used to judge whether the turbine actuator is in the state of not completing self-learning after being powered on when the engine is in the powered-on but not started state or the idle state; if so, the turbine actuator enters the self-learning mode to learn the left and right limit positions, and completes the self-learning work before the engine enters the working state; if not, the turbine actuator enters the initialization mode, and the turbine actuator enters the steady-state working state.

[0017] As a further limitation of the technical solution of the present invention, a self-learning execution module is used to drive the motor to rotate in the direction of closing the exhaust gas intake opening at a fixed speed in the self-learning mode, and judge whether the limit position is reached by the motor speed and the stall current; when the motor speed is less than the preset speed and the stall current is greater than the preset value, record the current limit position, and repeat the process to learn the limit position on the other side; if the turbine actuator is provided with an output shaft angle sensor, record the angle values reached by the limit positions on both sides; if the turbine actuator is not provided with an output shaft angle sensor, record the cumulative number of running steps of the motor from one limit position to the other limit position.

[0018] When the judgment condition is met, it is considered that the limit position on one side is reached, and the learned motor position is recorded; the judgment condition is that the motor speed is less than the preset speed, the stall current is greater than the preset value, and the holding state accumulates to reach the first time threshold; If the judgment condition is not met after exceeding the second time threshold, it is considered that the learning fails and enters the learning failure state.

[0019] As a further limitation of the technical solution of the present invention, the processing and control module is specifically configured to calculate the proportionality coefficient according to the output shaft angle and the opening percentage of the turbine actuator when the recorded information is the angle value reached by the two-side limit positions; and calculate the proportionality coefficient according to the cumulative number of motor running steps from one side limit to the other side limit position of the motor and the opening percentage of the turbine actuator when the recorded information is the cumulative number of motor running steps.

[0020] As a further limitation of the technical solution of the present invention, the device further includes a post-learning processing module, which is used to drive the opening of the turbine actuator to the default opening position required before the corresponding engine working state after the self-learning is completed, and the turbine actuator enters the steady-state working state.

[0021] The cascade PID control includes an outer-loop position PID control and an inner-loop speed PID control. The outer loop is responsible for controlling the forward rotation, reverse rotation and stop of the motor, and the inner loop is responsible for the specific speed regulation.

[0022] In a third aspect, the technical solution of the present invention further provides a turbine actuator, and the turbine actuator executes the request of the ECU as described in the first aspect and makes a target opening execution response.

[0023] As can be seen from the above technical solutions, the present application has the following advantages: By self-identifying various specified working conditions of the vehicle and performing self-learning of the turbine actuator, self-calibration of the turbine actuator is achieved, ensuring that the turbine actuator always obtains an accurate absolute opening value, thereby reducing the equipment installation cost and maintenance cost, ensuring the fuel economy and power reliability of the engine, reducing the risk of carbon deposition, reducing the loss of the vehicle engine, and thus extending the safe service life of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the present application, the drawings required for description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic flowchart of the method provided by the embodiment of the present invention.

[0026] Figure 2 It is a block diagram of the device provided by the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To make the application purpose, features, and advantages of this application more obvious and understandable, specific embodiments and accompanying drawings will be used below to clearly and completely describe the technical solutions protected by this application. Obviously, the embodiments described below are only a part of the embodiments of this application, rather than all embodiments. Based on the embodiments in this patent, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this patent.

[0028] As Figure 1 shown, an embodiment of the present invention provides a self-learning calibration method for a turbine actuator, including the following steps: S1: Obtain the real-time working condition information of the engine through the in-vehicle network signal, including the engine speed, accelerator pedal opening, and engine requested torque percentage; Through the in-vehicle network signal, obtain information such as the engine speed, accelerator pedal opening, and engine requested torque percentage to identify the power-on but not started state, idle state, and working state of the engine; the in-vehicle network signal includes but is not limited to bus communication methods such as CAN, LIN, and FlexRay.

[0029] S2: Identify the state of the engine according to the obtained working condition information, including the power-on but not started state, idle state, and working state; In this step, judge according to the obtained working condition information; The engine is powered on, the speed is equal to zero, and both the accelerator pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the power-on but not started state; The engine is powered on, the speed is at the low idle speed, and both the accelerator pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the idle state; The engine is powered on, the speed is higher than the low idle speed and is in a fluctuating state, and both the accelerator pedal opening and the engine requested torque percentage are greater than zero and are in a fluctuating state; it is determined that the engine is in the working state.

[0030] It should be noted here that the low idle speed is generally 500 - 800 rpm / min for a diesel engine and 700 - 1000 rpm / min for a gasoline engine.

[0031] S3: When the engine is in the power-on but not started state or the idle state, the turbine actuator enters the self-learning mode to learn the left and right extreme positions; Transmit the real-time engine working condition to the turbine state machine. When the engine is in the power-on but not started state and the idle state, and the turbine actuator is in the state of not completing self-learning after power-on, the turbine state machine jumps to the self-learning mode and completes the self-learning work before the engine enters the working state; the self-learning process is prohibited when the engine is in the working state.

[0032] S4: Calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle based on the learned limit positions. S5: Convert the requested opening percentage of the engine ECU into the control angle of the turbine actuator or the number of motor running steps through the proportional conversion coefficient, and drive the motor according to the cascade PID control, so that the turbine actuator executes the request of the ECU and makes a target opening execution response.

[0033] In the self-learning mode, drive the motor to learn the left and right limits respectively, and by default, one limit position is the opening 0 position; adopt a single speed loop control method to drive the motor to rotate at a fixed speed in the direction of closing the exhaust gas intake opening of the turbine actuator; judge by analyzing the running condition of the motor, combining the motor speed and the locked-rotor current magnitude obtained from the sampling resistance of the three-phase terminals of the motor. When the motor speed < 5 rpm / min and the locked-rotor current is greater than the tested locked-rotor current of the selected motor (usually five times the rated current of the selected motor), and both of the above two judgment conditions are satisfied and the state is accumulated and reaches 300 milliseconds, it is considered that one limit position is reached, and the learned motor position is saved; if the above judgment conditions are not satisfied within 10 s, it is considered that the learning fails and enters the learning failure state; after learning one limit position, learn and record the other limit position in the opposite direction in the same way as above; according to whether there is an output shaft angle sensor, record the angle values corresponding to the two limit positions or the cumulative number of motor running steps, calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the actual number of motor running steps or the output shaft angle; convert the requested turbine opening percentage of the engine ECU into the actual control angle of the turbine actuator or the number of motor running steps through the proportional conversion coefficient, and drive the motor according to the cascade PID control, so that the turbine actuator executes the requested opening of the ECU.

[0034] In some embodiments, when the engine is in the power-on but not started state or the idle state, the steps for the turbine actuator to enter the self-learning mode and learn the left and right limit positions include: When the engine is in the power-on but not started state or the idle state, judge whether the turbine actuator is in the state of not completing self-learning after power-on. If so, the turbine actuator enters the self-learning mode, learns the left and right limit positions, and completes the self-learning work before the engine enters the working state. If not, the turbine actuator enters the initialization mode, and the turbine actuator enters the steady-state working state.

[0035] In some embodiments, the steps for the turbine actuator to enter the self-learning mode and learn the left and right limit positions include: In the self-learning mode, the drive motor runs at a fixed speed in the direction of closing the exhaust gas intake opening, and determines whether the limit position is reached by the motor speed and the stall current; When the motor speed is less than the preset speed and the stall current is greater than the preset value, record the current limit position, and repeat the process to learn the limit position on the other side; If the turbine actuator is equipped with an output shaft angle sensor, record the angle values reached at the limit positions on both sides; if the turbine actuator is not equipped with an output shaft angle sensor, record the cumulative number of running steps of the motor from one limit position to the other limit position.

[0036] When the judgment conditions are met, it is considered that the limit position on one side is reached, and record the learned motor position; the judgment conditions are that the motor speed is less than the preset speed, the stall current is greater than the preset value, and the holding state accumulates to reach the first time threshold; If the judgment conditions are not met after exceeding the second time threshold, it is considered that the learning fails and enters the learning failure state.

[0037] The turbine actuator is fixed on the engine turbine structure assembly by mechanical connection, and is connected to the vehicle network and communicates with the engine ECU through in-vehicle network communication signal lines (including but not limited to bus communication methods such as CAN, LIN, FlexRay, etc.); the turbine actuator mainly consists of a circuit board, a DC motor and an external structure.

[0038] After the vehicle is powered on, the engine ECU and the turbine actuator communicate through in-vehicle network signals (including but not limited to bus communication methods such as CAN, LIN, FlexRay, etc.); In the turbine actuator software, there are two parts: the operation logic of the turbine state machine and the motor control logic; the operation logic of the turbine state machine mainly consists of an initialization mode, a diagnostic mode, a fault mode, an abnormal mode, and a self-learning mode; after being powered on, the turbine actuator enters the initialization mode, makes judgments through the judgment conditions between modes, performs jumps between modes, and executes corresponding work processes in their respective modes; among them, the engine condition recognition module and the self-learning mode together constitute the self-learning calibration function of the turbine actuator.

[0039] Transmit the engine working conditions to the turbine state machine in real time. The turbine state machine will accurately judge the self-learning timing according to the engine working condition state and perform the processing of whether to perform learning; when the engine is in the state of being powered on but not started and the idle state, and the turbine actuator is in the state of not completing self-learning after being powered on, the turbine state jumps to the self-learning mode, and the self-learning work must be completed before the engine enters the working state; when the engine is in the working state, the self-learning process is prohibited to avoid affecting the normal working response state of the engine.

[0040] The self-learning mode will drive the motor to learn towards the left and right extreme positions respectively. By default, one extreme position is the opening degree 0 position; in the self-learning mode, a single speed loop control method is adopted to drive the motor to rotate in the direction of closing the exhaust gas intake opening of the drive turbine actuator at a fixed speed (e.g., 500 rpm / min) (the basis for judging the left and right directions); by analyzing the operation of the motor, combined with the motor speed and the locked-rotor current magnitude obtained from the sampling resistors at the three-phase terminals of the motor for judgment; when the motor speed is close to 0, that is, the motor speed < 5 rpm / min, and the locked-rotor current is greater than the tested locked-rotor current of the selected motor (usually five times the rated current of the selected motor is used as the judgment standard); when both of the above two judgment conditions are met and the state is maintained for a cumulative 300 milliseconds, it can be considered that one extreme position has been reached, and the learned motor position is saved; if the above judgment conditions are not met within 10 s, it is considered that the learning fails, there is an abnormality, and the learning mode is entered; if the learning of one extreme position is successful, then in the opposite direction, in the same way and with the same judgment method as above, the motor is driven and the other extreme position is learned and recorded; For the processing and conversion of the two extreme positions, if the turbine actuator design has an output shaft angle sensor, record an angle value that can be reached by the two extreme positions at this time. If there is no output shaft angle sensor, record the cumulative number of running steps of the motor from one extreme 0 to the other extreme position; calculate a corresponding proportional conversion coefficient between the opening percentage of the turbine actuator and the actual number of running steps of the motor or the output shaft angle through a formula; through the proportional conversion coefficient, the requested turbine actuator opening percentage of the engine ECU can be converted into the actual control angle of the turbine actuator or the number of running steps of the motor according to the above formula; then, according to the cascade PID control, the motor can be driven to make the turbine actuator execute the request of the ECU and make an accurate target opening execution response.

[0041] The opening percentage of the turbine actuator represents the opening degree of the turbine actuator (for example, 0% means fully closed and 100% means fully open). In order to achieve precise control, it is necessary to convert the requested opening percentage sent by the engine ECU (electronic control unit) into the actual control parameters of the turbine actuator, that is, the number of running steps of the motor or the angle of the output shaft.

[0042] The proportional conversion coefficient is a mathematical relationship used to correspond the opening percentage with the actual control parameters (number of motor steps or output shaft angle). Through this coefficient, the requested opening percentage of the ECU can be converted into the specific actions that the turbine actuator needs to execute (such as how many steps the motor rotates or how many degrees the output shaft rotates).

[0043] When the recorded information is the angle values reached by the two extreme positions, that is, when there is an output shaft angle sensor, calculate the proportional coefficient according to the output shaft angle and the opening percentage of the turbine actuator; ; This formula represents the output shaft angle corresponding to each 1% opening percentage.

[0044] Since the turbine actuator has two limit positions during operation: the left limit position (usually corresponding to the fully closed state of the turbine actuator) and the right limit position (usually corresponding to the fully open state of the turbine actuator). To ensure that the turbine actuator can accurately respond to the requested opening of the ECU, it is necessary to know the specific control parameters (angle values or motor steps) corresponding to these two limit positions.

[0045] During the self-learning process, the turbine actuator records the output shaft angle values corresponding to the left and right limit positions. For example: Left limit position: The output shaft angle is 0 degrees.

[0046] Right limit position: The output shaft angle is 90 degrees.

[0047] In this way, the opening range of the turbine actuator is from 0 degrees to 90 degrees, and the opening percentage and the output shaft angle can be corresponding through a proportional conversion coefficient.

[0048] ; Opening percentage range = 100% (i.e., from 0% to 100%); Proportional conversion coefficient: 90 degrees / 100% = 0.9 degrees / %.

[0049] If the ECU requests an opening of 50%, the turbine actuator needs to rotate the output shaft to 45 degrees (50% × 0.9 degrees / %).

[0050] When the recorded information is the cumulative number of motor steps from one limit position to the other limit position of the motor, that is, when there is no output shaft sensor, calculate the proportional coefficient according to the cumulative limit position motor steps and the opening percentage of the turbine actuator.

[0051] , this formula represents the number of motor steps corresponding to each 1% opening percentage; If the turbine actuator does not have an output shaft angle sensor, the angle of the output shaft cannot be directly measured. At this time, the turbine actuator indirectly represents the opening through the number of motor steps. During the self-learning process, the turbine actuator records the cumulative number of motor steps from the left limit position to the right limit position. For example: Left limit position: The number of motor steps is 0 steps.

[0052] Right limit position: The number of motor steps is 1000 steps.

[0053] In this way, the opening range of the turbine actuator is from 0 steps to 1000 steps, and the percentage opening can be corresponded to the motor steps through a proportional conversion coefficient.

[0054] Left limit position: The motor steps are 0 steps.

[0055] Right limit position: The motor steps are 1000 steps.

[0056] Proportional conversion coefficient: 1000 steps / 100% = 10 steps / %

[0057] If the ECU requests an opening of 50%, the turbine actuator needs to run the motor 500 steps (50% × 10 steps / % ).

[0058] Percentage opening range = 100% (i.e., from 0% to 100% ).

[0059] ; According to the above formula, the number of steps at the left limit position = 0 steps; The number of steps at the right limit position = 1000 steps; Range of the cumulative running steps of the motor = 1000 steps - 0 steps = 1000 steps; Proportional conversion coefficient = 1000 steps / 100% = 10 steps / % ; If the ECU requests an opening of 50%, the running steps of the motor = 50% × 10 steps / % = 500 steps.

[0060] Through the above formula, the turbine actuator can accurately calculate the angle that the output shaft needs to rotate or the number of steps that the motor needs to run according to the requested opening percentage of the ECU, so as to achieve accurate control of the turbine opening.

[0061] After the self - learning is completed, drive the turbine actuator to the default opening position required before the corresponding engine working state, and the turbine actuator enters the steady - state working state.

[0062] On the one hand, it is possible to cancel the accessory package of the separate turbine actuator calibrator or the calibration process using a dedicated vehicle diagnostic instrument, reducing the product cost and installation cost of the turbine actuator, simplifying the installation or replacement process and improving the installation efficiency; on the other hand, by adding an active learning calibration function, compared with the traditional passive learning calibration function, the calibration frequency of the turbine actuator is increased, so as to ensure the long - term accuracy of the turbine actuator opening, thereby reducing phenomena such as carbon deposition and knocking caused by uneven mixture due to inaccurate intake in the vehicle, ensuring the fuel economy and power reliability of the vehicle, thus reducing the vehicle maintenance cost and extending the normal service life of the vehicle.

[0063] In the embodiment of the present invention, the cascade PID control includes an outer-loop position PID control and an inner-loop speed PID control. The outer loop is responsible for controlling the forward rotation, reverse rotation and stopping of the motor, and the inner loop is responsible for the specific speed regulation. Through this hierarchical control, more accurate and stable control of the opening of the turbine actuator can be achieved.

[0064] The main objective of the outer-loop position PID control is to control the opening position of the turbine actuator, that is, according to the requested opening percentage from the engine ECU, calculate the target position (output shaft angle or motor running steps) that the turbine actuator needs to reach, and achieve the control of the target position by adjusting the rotation direction and stopping of the motor. The specific control process is as follows: Input: The requested opening percentage sent by the engine ECU.

[0065] Target position calculation: Convert the requested opening percentage into the target position (output shaft angle or motor running steps) according to the proportional conversion coefficient.

[0066] Position error calculation: Compare the actual position of the current turbine actuator with the target position, and calculate the position error.

[0067] Position error = Target position - Actual position PID regulation: According to the position error, use the PID controller to calculate the control signal of the motor (usually the rotation direction, speed and stop command of the motor).

[0068]

[0069] Among them, is the proportional gain, which is used to quickly respond to the position error. is the integral gain, which is used to eliminate the steady-state error. is the derivative gain, which is used to suppress the oscillation of the system.

[0070] Output: Transmit the control signal to the inner-loop speed PID controller as the target speed of the inner loop.

[0071] When the target position is greater than the actual position, the outer loop controls the motor to rotate forward, so that the turbine actuator moves in the opening direction. When the target position is less than the actual position, the outer loop controls the motor to rotate in reverse, so that the turbine actuator moves in the closing direction. When the target position is consistent with the actual position, the outer loop controls the motor to stop, and maintains the current position of the turbine actuator.

[0072] The main objective of the inner-loop speed PID control is to control the rotational speed of the motor, that is, according to the target speed output by the outer-loop position PID controller, adjust the actual rotational speed of the motor to make it reach the target speed quickly and smoothly. The specific control process is as follows: Input: The target speed output by the outer-loop position PID controller.

[0073] Speed error calculation: Compare the actual speed of the motor with the target speed and calculate the speed error.

[0074] Speed error = Target speed - Actual speed PID regulation: Based on the speed error, use a PID controller to calculate the drive signal for the motor (usually a PWM signal or a voltage signal).

[0075]

[0076] Among them, is the proportional gain, which is used to quickly respond to the speed error. is the integral gain, which is used to eliminate the steady-state error. is the derivative gain, which is used to suppress the oscillation of the system.

[0077] Output: Transmit the drive signal to the motor, adjust the speed of the motor, and make it reach the target speed.

[0078] According to the target speed of the outer loop, accurately control the speed of the motor to ensure that the turbine actuator can reach the target position smoothly and quickly. When the motor starts, stops, or changes direction, the inner-loop speed PID controller can respond quickly to avoid sudden changes in the motor speed, reduce system oscillation and overshoot.

[0079] In the embodiment of the present invention, the outer-loop position PID controller calculates the target position of the turbine actuator according to the requested opening percentage of the engine ECU and outputs the target speed to the inner-loop speed PID controller. The inner-loop speed PID controller adjusts the actual speed of the motor according to the target speed of the outer loop, so that the motor can reach the target speed quickly and smoothly. The motor rotates forward, backward, or stops according to the drive signal of the inner loop, driving the turbine actuator to reach the target position. The actual position of the turbine actuator and the actual speed of the motor are fed back to the outer-loop and inner-loop controllers through sensors to form a closed-loop control, ensuring the accuracy and stability of the system.

[0080] Assume that the engine ECU requests the opening of the turbine actuator to be 50%, and the opening range of the turbine actuator is 0% to 100%, corresponding to the output shaft angle of 0 degrees to 90 degrees.

[0081] Outer-loop position PID control: Target position = 50% × 0.9 degrees / % = 45 degrees.

[0082] Actual position = 30 degrees (assuming the current opening of the turbine actuator is 30%).

[0083] Position error = 45 degrees - 30 degrees = 15 degrees.

[0084] The outer - loop PID controller calculates the target speed (for example, the motor needs to rotate forward at a speed of 500 rpm / min).

[0085] Inner - loop speed PID control: The target speed = 500 rpm / min.

[0086] The actual speed = 300 rpm / min (assuming the current motor speed is 300 rpm / min).

[0087] The speed error = 500 rpm / min - 300 rpm / min = 200 rpm / min.

[0088] The inner - loop PID controller calculates the drive signal to adjust the motor speed to reach 500 rpm / min.

[0089] Motor response: The motor rotates forward at a speed of 500 rpm / min, driving the turbine actuator to move in the opening direction until the actual position reaches 45 degrees.

[0090] When the actual position approaches 45 degrees, the outer - loop PID controller gradually reduces the target speed, and the inner - loop PID controller gradually reduces the motor speed, finally making the turbine actuator stop stably at the 45 - degree position. Through the coordinated control of the outer - loop and the inner - loop, the turbine actuator can accurately and stably respond to the requested opening of the engine ECU, ensuring the normal operation of the turbocharging system.

[0091] As Figure 2 shown, the embodiment of the present invention also provides a self - learning calibration device for a turbine actuator, including a working condition information acquisition module, an engine state recognition module, a self - learning execution module, and a processing and control module; The working condition information acquisition module is used to obtain the real - time working condition information of the engine through the in - vehicle network signal, including the engine speed, the throttle pedal opening, and the engine requested torque percentage; The engine state recognition module is used to identify the state of the engine according to the acquired working condition information, including the power - on but not started state, the idle state, and the working state; The self - learning execution module is used to enable the turbine actuator to enter the self - learning mode to perform the learning of the left and right limit positions when the engine is in the power - on but not started state or the idle state; The processing control module is used to calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle according to the learned limit positions; through the proportional conversion coefficient, convert the requested opening percentage of the engine ECU into the control angle or the number of motor running steps of the turbine actuator, and drive the motor according to the cascade PID control to make the turbine actuator execute the request of the ECU and make a target opening execution response.

[0092] In some embodiments, the engine state recognition module judges according to the obtained operating condition information; the engine is powered on, the rotational speed is zero, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the powered-on but not started state; the engine is powered on, the rotational speed is at the low idle speed, and both the throttle pedal opening and the engine requested torque percentage are zero; it is determined that the engine is in the idle state; the engine is powered on, the rotational speed is higher than the low idle speed and is in a fluctuating state, and both the throttle pedal opening and the engine requested torque percentage are greater than zero and are in a fluctuating state; it is determined that the engine is in the working state.

[0093] In some embodiments, the self-learning execution module is used to judge whether the turbine actuator is in the state of not completing self-learning after being powered on when the engine is in the powered-on but not started state or the idle state; if so, the turbine actuator enters the self-learning mode, learns the left and right limit positions, and completes the self-learning work before the engine enters the working state; if not, the turbine actuator enters the initialization mode, and the turbine actuator enters the steady-state working state.

[0094] In some embodiments, the self-learning execution module is used to drive the motor to rotate in the direction of closing the exhaust gas intake opening at a fixed speed in the self-learning mode, and judge whether the limit position is reached by the motor speed and the stall current; when the motor speed is less than the preset speed and the stall current is greater than the preset value, record the current limit position, and repeat the process to learn the limit position on the other side; if the turbine actuator is provided with an output shaft angle sensor, record the angle values reached by the two limit positions; if the turbine actuator is not provided with an output shaft angle sensor, record the cumulative number of running steps of the motor from one limit position to the other limit position.

[0095] When the judgment condition is satisfied, it is considered that the limit position on one side is reached, and the learned motor position is recorded; the judgment condition is that the motor speed is less than the preset speed, the stall current is greater than the preset value, and the holding state accumulates to reach the first time threshold; If the judgment condition is not satisfied after exceeding the second time threshold, it is considered that the learning fails and enters the learning failure state.

[0096] In some embodiments, the processing control module is specifically used to calculate the proportional coefficient according to the output shaft angle and the opening percentage of the turbine actuator when the recorded information is the angle values reached by the two limit positions; ;

[0097] When the recorded information is the cumulative number of running steps of the motor from one side limit to the other side limit position, the proportionality coefficient is calculated according to the cumulative number of running steps of the motor at the limit position and the opening percentage of the turbine actuator.

[0098] ;

[0099] When the recorded information is the cumulative number of running steps of the motor from one side limit to the other side limit position, the proportionality coefficient is calculated according to the cumulative number of running steps of the motor at the limit position and the opening percentage of the turbine actuator.

[0100] The device further includes a post-learning processing module, which is used to drive the opening of the turbine actuator to the default opening position required before the corresponding engine working state after the self-learning is completed, and the turbine actuator enters the steady-state working state.

[0101] The cascade PID control includes an outer-loop position PID control and an inner-loop speed PID control. The outer loop is responsible for controlling the forward rotation, reverse rotation and stop of the motor, and the inner loop is responsible for the specific speed regulation. It should be noted that the self-learning execution module and the processing control module belong to the turbine actuator. The turbine actuator receives the engine state information output by the engine state recognition module, and transmits the engine working condition to the turbine state machine in real time. The turbine state machine will accurately judge the self-learning opportunity according to the engine working condition state and perform the processing of whether to perform learning.

[0102] An embodiment of the present invention further provides a turbine actuator, and the turbine actuator executes the request of the ECU according to the method described in the above embodiment and makes a target opening execution response.

[0103] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A self-learning calibration method for a turbine actuator, characterized in that: The steps include: Obtain real-time engine operating information through vehicle network signals, including engine speed, accelerator pedal opening, and engine requested torque percentage; According to the acquired working condition information, the engine status is identified, including the power-on but not started status, the idle status and the working status; When the engine is powered on but not started or in idling state, the turbine actuator enters the self-learning mode to learn the left and right limit positions; According to the learned limit position, the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle is calculated; The requested opening percentage of the engine ECU is converted into the control angle of the turbine actuator or the number of motor running steps through the proportional conversion coefficient. The drive motor is controlled according to the cascade PID control, so that the turbine actuator executes the request of the ECU and makes a target opening execution response.

2. The self-learning calibration method for a turbine actuator according to claim 1, characterized in that: According to the acquired operating condition information, the steps of identifying the state of the engine include: Judge based on the working condition information obtained; The engine is powered on, the speed is zero, and the accelerator pedal opening and the engine request torque percentage are both zero; it is determined that the engine is in a powered-on but not started state; The engine is powered on, the speed is at the idle low speed, and the accelerator pedal opening and the engine request torque percentage are both zero; the engine is judged to be in the idle state; The engine is powered on, the speed is higher than the idle low speed and is in a fluctuating state, the accelerator pedal opening and the engine requested torque percentage are both greater than zero and are in a fluctuating state; it is determined that the engine is in a working state.

3. The self-learning calibration method for a turbine actuator according to claim 2, characterized in that: When the engine is powered on but not started or in idling state, the turbine actuator enters the self-learning mode. The steps for learning the left and right limit positions include: When the engine is powered on but not started or in an idling state, determine whether the turbine actuator is in a state where self-learning has not been completed after power-on; If so, the turbine actuator enters the self-learning mode, learns the left and right limit positions, and completes the self-learning work before the engine enters the working state; If not, the turbine actuator enters the initialization mode and the turbine actuator enters the steady-state working state.

4. The self-learning calibration method for a turbine actuator according to claim 3, characterized in that: The turbine actuator enters the self-learning mode, and the steps for learning the left and right limit positions include: In the self-learning mode, the drive motor runs at a fixed speed in the direction of closing the exhaust gas intake opening, and determines whether the limit position has been reached by the motor speed and the stall current; When the motor speed is less than the preset speed and the stall current is greater than the preset value, the current limit position is recorded and the process is repeated to learn the limit position on the other side; If the turbine actuator is equipped with an output shaft angle sensor, record the angle values ​​reached at the extreme positions on both sides; if the turbine actuator is not equipped with an output shaft angle sensor, record the cumulative number of running steps of the motor from the extreme position on one side to the extreme position on the other side.

5. The self-learning calibration method for a turbine actuator according to claim 4, characterized in that: The steps of judging whether the limit position has been reached by the motor speed and the stall current include: When the judgment condition is met, it is considered that the limit position on one side is reached, and the learned motor position is recorded; the judgment condition is that the motor speed is less than the preset speed and the stall current is greater than the preset value and the holding state reaches the first time threshold cumulatively; If the second time threshold is exceeded and the judgment condition is not met, it is considered that the learning has failed and the learning has entered a learning failure state.

6. The self-learning calibration method for a turbine actuator according to claim 5, characterized in that: The steps of calculating the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor operation steps or the output shaft angle according to the learned limit position include: When the recorded information is the angle value reached by the extreme positions on both sides, the proportional coefficient is calculated based on the output shaft angle and the opening percentage of the turbine actuator; When the recorded information is the cumulative number of running steps of the motor from the limit position on one side to the limit position on the other side, the proportional coefficient is calculated based on the cumulative number of running steps of the motor at the limit position and the opening percentage of the turbine actuator.

7. The self-learning calibration method for a turbine actuator according to claim 6, characterized in that: The method further includes: After the self-learning is completed, the turbine actuator is driven to open to the default opening position required before the corresponding engine working state, and the turbine actuator enters a steady-state working state.

8. The self-learning calibration method for a turbine actuator according to claim 7, characterized in that: The cascade PID control includes an outer loop position PID control and an inner loop speed PID control, wherein the outer loop is responsible for controlling the forward rotation, reverse rotation and stop of the motor, and the inner loop is responsible for specific speed regulation.

9. A self-learning calibration device for a turbine actuator, characterized in that: It includes a working condition information acquisition module, an engine state recognition module, a self-learning execution module and a processing control module; The working condition information acquisition module is used to obtain the real-time working condition information of the engine through the vehicle network signal, including the engine speed, the accelerator pedal opening, and the engine requested torque percentage; The engine state recognition module is used to recognize the state of the engine according to the acquired working condition information, including the power-on but not started state, the idle state and the working state; The self-learning execution module is used for the turbine actuator to enter the self-learning mode and learn the left and right limit positions when the engine is powered on but not started or in the idling state; The processing control module is used to calculate the proportional conversion coefficient between the opening percentage of the turbine actuator and the number of motor running steps or the output shaft angle according to the learned limit position; the opening percentage requested by the engine ECU is converted into the control angle of the turbine actuator or the number of motor running steps through the proportional conversion coefficient, and the motor is driven according to the cascade PID control so that the turbine actuator executes the request of the ECU and makes a target opening execution response.

10. A turbine actuator, characterized in that: The turbine actuator executes the method according to any one of claims 1 to 8 to execute the request of the ECU and make a target opening execution response.

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