Pressure sensor null drift diagnosis method and device and vehicle

Abstract

The invention discloses a pressure sensor null drift diagnosis method and device and a vehicle. After a rotation stopping instruction for an engine is detected, the rotating speed of the engine is obtained; whether the current rotating speed of the engine meets a preset condition or not is judged, if the current rotating speed of the engine meets the preset condition, it is indicated that the engine executes an instruction of stopping rotating, the current of an oil cylinder electromagnetic valve matched with a pressure sensor is configured to be a first current value, and the oil cylinder electromagnetic valve works at the first current value for a first preset duration. And after the first preset duration is kept, the current value of the oil cylinder electromagnetic valve is detected, if the current value is about to reach a second current value, it is indicated that pressure relief of the hydraulic system is completed, and null drift diagnosis is conducted on the pressure sensor. Namely, when the engine is about to stop rotating, active pressure relief of the hydraulic system is realized by controlling the current of the electromagnetic valve of the oil cylinder, and the pressure relief time is shortened, so that the zero drift of the pressure sensor is quickly diagnosed.

Description

Technical Field

[0001] This application relates to the technical field of data processing, and in particular to a method and device for diagnosing zero drift of a pressure sensor and a vehicle. Background Art

[0002] As an important component on a vehicle, a pressure sensor needs to be fault-detected to ensure driving safety of the vehicle. Currently, the fault diagnosis of the pressure sensor is carried out after determining whether the hydraulic system has been depressurized based on the oil temperature of the hydraulic system and the depressurization time. However, in the above method, the depressurization time is affected by the oil temperature. The lower the oil temperature, the longer the automatic depressurization time. If the zero drift of the pressure sensor is detected in a state where the hydraulic system has not been fully depressurized, a fault of excessive zero drift may be falsely reported due to the residual pressure of the hydraulic system. Summary of the Invention

[0003] In view of this, this application provides a method and device for diagnosing zero drift of a pressure sensor and a vehicle to improve the diagnosis speed of the zero drift of the pressure sensor.

[0004] To solve the above problems, the technical solutions provided in this application are as follows:

[0005] In the first aspect of this application, a method for diagnosing zero drift of a pressure sensor is provided. The method includes:

[0006] In response to detecting a stop rotation instruction for the engine, obtain the rotational speed of the engine;

[0007] If the rotational speed meets a preset condition, configure the current of the oil cylinder solenoid valve matched with the pressure sensor to a first current value, and control the current of the oil cylinder solenoid valve to maintain the first current value for a first preset duration;

[0008] If the current value of the oil cylinder solenoid valve drops to a second current value after maintaining the first preset duration, perform zero drift diagnosis on the pressure sensor.

[0009] In a possible implementation manner, if the pressure sensor is an absolute pressure sensor and the pressure sensor is located on a plateau, before performing zero drift diagnosis on the pressure sensor, the method further includes:

[0010] Obtain a zero drift compensation value matched with the height of the plateau;

[0011] Use the zero drift compensation value to perform zero drift compensation on the pressure sensor.

[0012] In a possible implementation manner, obtaining a zero drift compensation value matched with the height of the plateau includes:

[0013] Obtain the current atmospheric pressure value corresponding to the plateau through a barometric pressure sensor;

[0014] Obtain a zero-drift compensation value based on the current atmospheric pressure value and the standard atmospheric pressure value.

[0015] In a possible implementation, the cylinder solenoid valve matched with the pressure sensor includes a main cylinder solenoid valve and / or a slave cylinder solenoid valve.

[0016] In a possible implementation, the preset condition includes that the rotational speed is less than a preset rotational speed value and the duration is not less than a second preset duration.

[0017] In a possible implementation, the method further includes:

[0018] If the rotational speed of the engine does not meet the preset condition during the period when the current of the cylinder solenoid valve remains at the first current value, adjust the current of the cylinder solenoid valve according to the rotational speed of the engine.

[0019] In a possible implementation, the method includes:

[0020] In response to the moment of engine startup, perform zero-drift diagnosis on the pressure sensor at 0 bar;

[0021] If the zero-drift diagnosis of the pressure sensor passes, use the offset value of the pressure sensor at 0 bar as the drift value at 1 bar.

[0022] In a possible implementation, the method further includes:

[0023] Determine a command pressure value according to the hydraulic control target value and the drift value.

[0024] In a second aspect of the present application, there is provided a pressure sensor zero-drift diagnosis device, the device includes:

[0025] An acquisition unit, configured to obtain the rotational speed of the engine in response to detecting a stop rotation instruction for the engine;

[0026] A configuration unit, configured to, if the rotational speed meets the preset condition, configure the current of the cylinder solenoid valve matched with the pressure sensor to a first current value, and control the current of the cylinder solenoid valve to maintain the first current value for a first preset duration;

[0027] A diagnosis unit, configured to perform zero-drift diagnosis on the pressure sensor if the current value of the cylinder solenoid valve drops to a second current value.

[0028] In a possible implementation, if the pressure sensor is an absolute pressure sensor and the pressure sensor is located on the plateau, before performing zero-drift diagnosis on the pressure sensor, the device further includes: a compensation unit;

[0029] The obtaining unit is further configured to obtain a zero-drift compensation value matching the altitude of the plateau;

[0030] The compensation unit is configured to perform zero-drift compensation on the pressure sensor by using the zero-drift compensation value.

[0031] In a possible implementation manner, the obtaining unit is specifically configured to obtain a current atmospheric pressure value corresponding to the plateau through a barometric pressure sensor; and obtain a zero-drift compensation value based on the current atmospheric pressure value and a standard atmospheric pressure value.

[0032] In a possible implementation manner, the oil cylinder solenoid valve equipped with the pressure sensor includes a main oil cylinder solenoid valve and / or a slave oil cylinder solenoid valve.

[0033] In a possible implementation manner, the preset condition includes that the rotational speed is less than a preset rotational speed value and the duration is not less than a second preset duration.

[0034] In a possible implementation manner, the device further includes: an adjustment unit;

[0035] The adjustment unit is configured to, if the rotational speed of the engine does not meet the preset condition during the period when the current of the oil cylinder solenoid valve remains at the first current value, adjust the current of the oil cylinder solenoid valve according to the rotational speed of the engine.

[0036] In a possible implementation manner, the diagnosis unit is further configured to perform zero-drift diagnosis on the pressure sensor at 0 bar in response to the instant when the engine starts;

[0037] The configuration unit is further configured to, if the zero-drift diagnosis of the pressure sensor passes, use the offset value of the pressure sensor at 0 bar as the drift value at 1 bar.

[0038] In a possible implementation manner, the device further includes: a determination unit;

[0039] The determination unit is configured to determine a command pressure value according to a hydraulic control target value and the drift value.

[0040] In a third aspect of the present application, a vehicle is provided, including: a pressure sensor and the diagnosis device described in the second aspect;

[0041] The pressure sensor is configured to detect the pressure of the oil cylinder on the vehicle;

[0042] The diagnosis device is configured to perform zero-drift diagnosis on the pressure sensor.

[0043] In a fourth aspect of the present application, an electronic device is provided, including: a processor and a memory;

[0044] The memory is used to store computer-readable instructions or computer programs;

[0045] The processor is configured to read the computer-readable instructions or the computer program, so that the device implements the zero-drift diagnosis method of the pressure sensor described in the first aspect.

[0046] Thus, the present application has the following beneficial effects:

[0047] In the present application, after detecting a stop rotation instruction for the engine, the rotational speed of the engine is obtained. It is determined whether the rotational speed of the current engine meets a preset condition. If the preset condition is met, indicating that the engine is executing the stop rotation instruction, the current of the oil cylinder solenoid valve matched with the pressure sensor is configured to a first current value and the oil cylinder solenoid valve is made to work at the first current value for a first preset duration. After maintaining the first preset duration, the current value of the oil cylinder solenoid valve is detected. If its current value drops to a second current value, indicating that the hydraulic system has been depressurized, zero-drift diagnosis of the pressure sensor is performed. That is, when the engine is about to stop rotating, active pressure relief of the hydraulic system is achieved by controlling the current of the oil cylinder solenoid valve, shortening the pressure relief time, thereby enabling rapid zero-drift diagnosis of the pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the composition structure of a hydraulic system provided by an embodiment of the present application;

[0049] Figure 2 It is a schematic diagram of the flow of a zero-drift diagnosis method of a pressure sensor provided by an embodiment of the present application;

[0050] Figure 3 It is a schematic diagram of the relationship between the current of an oil cylinder solenoid valve and pressure provided by an embodiment of the present application;

[0051] Figure 4 It is a schematic diagram of active pressure relief data comparison provided by an embodiment of the present application;

[0052] Figure 5 It is a schematic diagram of the difference in pressure accuracy under different pressures provided by an embodiment of the present application;

[0053] Figure 6 It is a structural diagram of a zero-drift diagnosis device for a pressure sensor provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] To make the above objects, features, and advantages of the present application more obvious and understandable, the following further details the embodiments of the present application in conjunction with the accompanying drawings and specific embodiments.

[0055] With the consideration of fuel economy and emission standards, the application of the start-stop function of vehicles has attracted more and more attention. The start-stop function is the engine automatic start-stop function. Engine automatic start-stop means that when the vehicle stops temporarily during driving (such as waiting for a red light), the engine will automatically turn off; when it is necessary to move forward again, the system will automatically restart the engine. To ensure the normal operation of the start-stop function, it is necessary to perform fault diagnosis on the pressure sensor under the start-stop function.

[0056] Currently, the zero-drift diagnosis of the pressure sensor is mainly based on the oil temperature of the hydraulic system and the pressure relief time. After determining that the hydraulic system has completed pressure relief, the fault diagnosis of the pressure sensor is carried out. Among them, the composition of the hydraulic system is as Figure 1 shown. This system includes an active cylinder, a driven cylinder, an active cylinder pressure regulating valve, a driven cylinder pressure regulating valve, a main oil circuit pressure regulating valve, an engine, a suction filter, an oil pan, and an engine oil pressure sensor EOP. EOP actively fills the oil cavity when the engine is not started, so that the system response time is relatively fast. The oil supply flow rate of the oil pump increases with the increase of the engine speed. The system adjusts the main oil circuit pressure through the main oil circuit pressure regulating valve, which is used as the input of the direct drive solenoid valves of the active cylinder and the driven cylinder. By controlling the direct drive valves, the pressures of the main and driven cylinders are controlled, thereby changing the steel belt speed ratio; the excess flow is overflowed to the secondary oil circuit through the main oil circuit pressure regulating valve to supply the actuator and lubrication and cooling, etc.

[0057] Since the pressure relief time is affected by the oil temperature, the automatic pressure relief time is longer when the oil temperature is lower, which affects the diagnosis efficiency. Among them, the fault diagnosis of the pressure sensor is mainly to judge whether the zero drift of the pressure sensor exceeds the threshold. If it exceeds the threshold, it is determined that the pressure sensor is faulty. Among them, the zero-point drift of the pressure sensor means that under the specified test conditions, when the input pressure of the pressure sensor is zero, its corresponding output value jumps positively, negatively, or up and down over the specified index (threshold) with time.

[0058] Based on this, when the vehicle is about to stop, this application makes the hydraulic system quickly complete pressure relief by increasing the active pressure relief method, and then realizes the rapid fault diagnosis of the pressure sensor. At the same time, this application performs zero-drift diagnosis on the pressure sensor on the premise that the hydraulic system is completely pressure-relieved, so as to avoid misreporting the fault of excessive zero drift when there is residual pressure in the hydraulic system.

[0059] To facilitate the understanding of the technical solution of this application, it will be described below with reference to the accompanying drawings.

[0060] See Figure 2 , this figure is a flowchart of a method for diagnosing zero drift of a pressure sensor provided by an embodiment of this application. As Figure 2 shown, this method includes:

[0061] S201: In response to detecting a stop rotation instruction for the engine, obtain the engine speed.

[0062] S202: If the rotational speed of the engine meets a preset condition, configure the current of the oil cylinder solenoid valve equipped with a pressure sensor to a first current value, and control the current of the oil cylinder solenoid valve to maintain the first current value for a first preset duration.

[0063] In this embodiment, after detecting a stop rotation instruction for the engine, obtain the rotational speed of the engine and determine whether the rotational speed meets the preset condition. If it meets the preset condition, it indicates that the engine is executing the stop instruction, then configure the current of the oil cylinder solenoid valve equipped with a pressure sensor to the first current value and control the current of the oil cylinder solenoid valve to maintain the first current value for the first preset duration. That is, active pressure relief is achieved by setting the current of the oil cylinder solenoid valve to the first current value, accelerating the pressure relief. If the preset condition is not met, it indicates that the engine is still operating normally, then determine the current value of the oil cylinder solenoid valve according to the rotational speed of the engine to enable the normal operation of the vehicle.

[0064] Among them, the preset condition can be set according to the actual application situation. Specifically, the preset condition includes that the rotational speed is less than a preset rotational speed threshold and the duration is not less than a second preset duration. For example, the preset condition is that the rotational speed of the engine is less than 10 rpm and the duration is not less than 50 ms.

[0065] Among them, the first current value and the first preset duration can also be set according to the actual application situation, as long as it can enable the oil cylinder to achieve active pressure relief. The relationship between the current of the oil cylinder solenoid valve and the pressure of the oil cylinder can be obtained through experimental data, as Figure 3 shown. Through Figure 3 it can be known that when the solenoid valve current is greater than 800 mA, the pressure of the oil cylinder can be quickly reduced to 0 bar. At the same time, considering that the greater the current, the greater the corresponding power consumption, in order to reduce the power consumption and accelerate the pressure relief, the first current value can be set to 1050 mA and the first preset duration is 1 s.

[0066] Among them, the oil cylinder solenoid valve equipped with a pressure sensor can include an active oil cylinder solenoid valve and / or a driven oil cylinder solenoid valve. Specifically, set the currents of both the active oil cylinder solenoid valve and the driven oil cylinder solenoid valve to the first current value and maintain the first preset duration.

[0067] S203: If the current value of the oil cylinder solenoid valve drops to a second current value after maintaining the first preset duration, perform zero drift diagnosis on the pressure sensor.

[0068] In this embodiment, since the current of the oil cylinder solenoid valve remains at the first current value for the first preset duration, when the holding time exceeds the first preset duration, the current of the oil cylinder solenoid valve starts to decrease. When it drops to the second current value, it indicates that the oil cylinder has completed pressure relief, and then zero drift diagnosis of the pressure sensor is performed. Specifically, the real-time pressure value of the pressure sensor is obtained, and it is judged whether the difference between the real-time pressure value of the pressure sensor and the atmospheric pressure value exceeds the pressure difference threshold. If it does not exceed, the zero drift diagnosis passes; otherwise, the zero drift diagnosis fails.

[0069] It should be noted that to ensure complete pressure relief of the hydraulic system, after the current value of the oil cylinder solenoid valve is detected to reach the second current value, it still continues for the third preset duration. Among them, the second current value can be set according to the actual application scenario. For example, the second current value is 0 mA and the third preset duration is 1 s.

[0070] In one application scenario, during the period when the current of the oil cylinder solenoid valve remains at the first current value, if the engine speed does not meet the preset condition, it indicates that the engine starts, and then the current of the oil cylinder solenoid valve is adjusted according to the engine speed to ensure normal operation of the engine.

[0071] To show that this embodiment can accelerate pressure relief, refer to Figure 4 the comparison of two different methods shown in the figure. The abscissa is the time axis. When the engine stops rotating and reaches the flameout flag position, the automatic pressure relief curve is as Figure 4 shown by the dotted line, and it takes a certain period of time to complete pressure relief; while the active pressure relief strategy is that when reaching the flameout flag position, the starting solenoid valve current is controlled at 1050 mA and maintained for 1 s; under active pressure relief, the oil pressure in the cylinder responds in milliseconds, and the active pressure relief is completed in 170 milliseconds, greatly improving the pressure relief rate and the diagnosis speed of the pressure sensor.

[0072] Through the technical solution provided by this application, after detecting the stop rotation instruction for the engine, the engine speed is obtained. It is judged whether the current engine speed meets the preset condition. If it meets the preset condition, it indicates that the engine is executing the stop rotation instruction, and then the current of the oil cylinder solenoid valve matched with the pressure sensor is configured as the first current value and the oil cylinder solenoid valve is allowed to work at the first current value for the first preset duration. After maintaining the first preset duration, the current value of the oil cylinder solenoid valve is detected. If its current value drops to the second current value, it indicates that the hydraulic system has completed pressure relief, and then zero drift diagnosis of the pressure sensor is performed. That is, when the engine is about to stop rotating, the active pressure relief of the hydraulic system is realized by controlling the current of the oil cylinder solenoid valve, shortening the pressure relief time, so as to quickly diagnose the zero drift of the pressure sensor.

[0073] Since the current mainstream type of pressure sensor is the absolute pressure type, when a vehicle (equipped with a low-limit component of the pressure sensor) travels on the plateau, due to the low atmospheric pressure, the display value of the absolute pressure sensor is low under the plateau, resulting in an over-limit zero drift reported under the plateau and increasing the false alarm rate of the pressure sensor. To solve the above problems, this application provides a solution, that is, if the pressure sensor is an absolute pressure sensor and is located on the plateau, before zero drift diagnosis, the zero drift compensation value corresponding to the altitude of the plateau is obtained; the zero drift compensation value is used to perform zero drift compensation on the pressure sensor. Among them, obtaining the zero drift compensation value includes: obtaining the current atmospheric pressure value corresponding to the plateau through a barometric pressure sensor; obtaining the zero drift compensation value based on the current atmospheric pressure value and the standard atmospheric pressure value.

[0074] Specifically, first according to absolute pressure = gauge pressure + current atmospheric pressure;

[0075] Gauge pressure sensor: Gauge pressure display value = oil pressure;

[0076] Absolute pressure sensor: Absolute pressure display value = oil pressure + current atmospheric pressure.

[0077] For easy reading, it is necessary to output the display value of the absolute pressure sensor in the form of gauge pressure. The absolute pressure sensor is calibrated under the standard atmospheric pressure, so:

[0078] Gauge pressure display value of the absolute pressure sensor = oil pressure + current atmospheric pressure - standard atmospheric pressure

[0079] Based on the above formula, the compensation formula for compensating the atmospheric pressure difference of the absolute pressure sensor can be obtained:

[0080] Zero drift compensation value = standard atmospheric pressure - current atmospheric pressure.

[0081] For example, when the absolute pressure sensor is at 4000 meters, the atmospheric pressure is 0.6 bar and the standard atmospheric pressure is 1 bar, then the zero drift compensation value is 0.4 bar.

[0082] Furthermore, due to the individual differences of the pressure sensors and their different sensitivities to temperature and pressure, it is impossible to perform unified compensation on them, making the traditional closed-loop control unable to take into account the pressure deviation of the pressure sensor, with a rough control strategy, resulting in low economic benefits of the start-stop function and inaccurate control. Based on this, the embodiment of this application provides a solution. At the moment when the engine starts, if the zero drift diagnosis of the pressure sensor passes, its zero drift value is equivalently replaced with the output error under the environment of 1 bar (that is, the zero drift value under the environment of 1 bar), so as to perform zero drift compensation control.

[0083] In this embodiment, through experimental data, it can be known that the pressure accuracy difference between the pressure sensors at 0 bar and 1 bar is within 0.1 bar, such as Figure 5As shown above. Based on the above characteristics, when the zero-drift diagnosis of the pressure sensor at 0 bar passes, its zero-drift value is used as the correction value of the pressure sensor at 1 bar, realizing zero-drift compensation control, improving the closed-loop control accuracy of the low-pressure section of the oil cylinder, reducing the load power of starting and stopping the electronic oil pump, and improving the accuracy of the starting and stopping functions.

[0084] For easy understanding, take a certain pressure sensor with an actual offset of -0.56 bar at 0 bar and an offset of -0.58 bar at 1 bar. If the hydraulic control target is 1 bar and the pressure error is not considered, the commanded pressure is 1 bar, and the actual pressure given is 1 + (-0.58) = 0.42 bar. The error from the control target of 1 bar is (0.42 - 1) / 1 * 100% = -58%. After adopting the closed-loop control strategy with zero-drift compensation, the offset of -0.56 bar at 0 bar is regarded as the offset at 1 bar, and the control target is 1 bar. Considering that the pressure sensor error needs to be filled, the commanded pressure needs to be 1 - (-0.56) = 1.56 bar, and the actual pressure given is 1.56 + (-0.58) = 0.98 bar. The error from the control target of 1 bar is (0.98 - 1) / 1 * 100% = -2%.

[0085] Based on the above method embodiments, the embodiments of the present application further provide a pressure sensor zero-drift diagnosis device, which will be described below with reference to the accompanying drawings.

[0086] See Figure 6 , this figure is a structural diagram of a pressure sensor zero-drift diagnosis device provided by the embodiments of the present application. As Figure 6 shown, the device 600 includes: an acquisition unit 601, a configuration unit 602, and a diagnosis unit 603.

[0087] The acquisition unit 601 is configured to obtain the engine speed in response to detecting a stop rotation instruction for the engine.

[0088] The configuration unit 602 is configured to, if the speed meets a preset condition, configure the current of the oil cylinder solenoid valve matching the pressure sensor to a first current value, and control the current of the oil cylinder solenoid valve to maintain the first current value for a first preset duration.

[0089] The diagnosis unit 603 is configured to perform zero-drift diagnosis on the pressure sensor if the current value of the oil cylinder solenoid valve drops to a second current value.

[0090] In a possible implementation manner, if the pressure sensor is an absolute pressure sensor and the pressure sensor is located on the plateau, before performing zero-drift diagnosis on the pressure sensor, the device further includes: a compensation unit;

[0091] The obtaining unit 601 is further configured to obtain a zero-drift compensation value matching the altitude of the plateau;

[0092] The compensation unit is configured to perform zero-drift compensation on the pressure sensor by using the zero-drift compensation value.

[0093] In a possible implementation manner, the obtaining unit 601 is specifically configured to obtain the current atmospheric pressure value corresponding to the plateau through a barometric pressure sensor; and obtain a zero-drift compensation value based on the current atmospheric pressure value and the standard atmospheric pressure value.

[0094] In a possible implementation manner, the oil cylinder solenoid valve equipped with a pressure sensor includes a main oil cylinder solenoid valve and / or a slave oil cylinder solenoid valve.

[0095] In a possible implementation manner, the preset condition includes that the rotational speed is less than a preset rotational speed value and the duration is not less than a second preset duration.

[0096] In a possible implementation manner, the device further includes: an adjustment unit;

[0097] The adjustment unit is configured to, if the rotational speed of the engine does not meet the preset condition during the period when the current of the oil cylinder solenoid valve remains at the first current value, adjust the current of the oil cylinder solenoid valve according to the rotational speed of the engine.

[0098] In a possible implementation manner, the diagnosis unit 603 is further configured to perform zero-drift diagnosis on the pressure sensor at 0 bar in response to the instant when the engine starts;

[0099] The configuration unit 602 is further configured to, if the zero-drift diagnosis of the pressure sensor passes, use the offset value of the pressure sensor at 0 bar as the drift value at 1 bar.

[0100] In a possible implementation manner, the device further includes: a determination unit;

[0101] The determination unit is configured to determine a command pressure value according to the hydraulic control target value and the drift value.

[0102] It should be noted that the specific implementation of each unit in this embodiment can refer to the relevant descriptions in the above method embodiment, and will not be elaborated herein.

[0103] In addition, an embodiment of the present application provides a device, including: a processor, a memory;

[0104] The memory is used to store computer-readable instructions or computer programs;

[0105] The processor is configured to read the computer-readable instructions or the computer program, so that the device implements the zero-drift diagnosis method for the pressure sensor as described above.

[0106] An embodiment of the present application provides a computer-readable storage medium, including instructions or a computer program, which, when running on a computer, causes the computer to execute the zero-drift diagnosis method for the pressure sensor as described above.

[0107] It should be noted that the embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other. For the systems or devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions in the method part.

[0108] It should be understood that in the present application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally means an "or" relationship between the associated objects before and after. "At least one (one) of the following" or its similar expression means any combination of these items, including any combination of single item (one) or plural items (ones). For example, at least one (one) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a, b, and c", where a, b, and c can be single or multiple.

[0109] It should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the element.

[0110] The steps of the methods or algorithms described in connection with the embodiments disclosed herein may be implemented directly in hardware, in a software module executed by a processor, or in a combination thereof. The software module may be disposed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0111] The foregoing description of the disclosed embodiments enables those skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A zero-drift diagnosis method for a pressure sensor, characterized in that The method includes: In response to detecting a stop rotation instruction for the engine, obtaining the rotational speed of the engine; If the rotational speed meets a preset condition, configuring the current of the oil cylinder solenoid valve equipped with a pressure sensor to a first current value, and controlling the current of the oil cylinder solenoid valve to maintain the first current value for a first preset duration; If the current value of the oil cylinder solenoid valve drops to a second current value after maintaining the first preset duration, performing zero-drift diagnosis on the pressure sensor.

2. The method according to claim 1, characterized in that If the pressure sensor is an absolute pressure sensor and the pressure sensor is located on a plateau, before performing zero-drift diagnosis on the pressure sensor, the method further includes: Obtaining a zero-drift compensation value matching the height of the plateau; Using the zero-drift compensation value to perform zero-drift compensation on the pressure sensor.

3. The method according to claim 2, characterized in that Obtaining a zero-drift compensation value matching the height of the plateau includes: Obtaining the current atmospheric pressure value corresponding to the plateau through a barometric pressure sensor; Obtaining a zero-drift compensation value based on the current atmospheric pressure value and the standard atmospheric pressure value.

4. The method according to any one of claims 1-3, characterized in that The oil cylinder solenoid valve equipped with a pressure sensor includes a main oil cylinder solenoid valve and / or a slave oil cylinder solenoid valve.

5. The method according to claim 1, characterized in that The preset condition includes that the rotational speed is less than a preset rotational speed value and the duration is not less than a second preset duration.

6. The method according to claim 1, characterized in that The method further includes: If the rotational speed of the engine does not meet the preset condition during the period when the current of the oil cylinder solenoid valve remains at the first current value, adjusting the current of the oil cylinder solenoid valve according to the rotational speed of the engine.

7. The method according to claim 1, characterized in that The method includes: In response to the instant of engine startup, performing zero-drift diagnosis on the pressure sensor at 0 bar; If the zero-drift diagnosis of the pressure sensor passes, using the offset value of the pressure sensor at 0 bar as the drift value at 1 bar.

8. The method according to claim 7, characterized in that The method further includes: Determining a command pressure value according to the hydraulic control target value and the drift value.

9. A zero-drift diagnosis device for a pressure sensor, characterized in that The device includes: An acquisition unit, configured to obtain the rotational speed of the engine in response to detecting a stop rotation instruction for the engine; A configuration unit, configured to, if the rotational speed meets a preset condition, configure the current of the oil cylinder solenoid valve equipped with a pressure sensor to a first current value, and control the current of the oil cylinder solenoid valve to maintain the first current value for a first preset duration; A diagnosis unit, configured to perform zero-drift diagnosis on the pressure sensor if the current value of the oil cylinder solenoid valve drops to a second current value.

10. A vehicle, characterized in that Includes: A pressure sensor and the diagnosis device according to claim 9; The pressure sensor is configured to detect the oil cylinder pressure on the vehicle; The diagnosis device is configured to perform zero-drift diagnosis on the pressure sensor.

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