A method for estimating the steering wheel zero position applied to a redundant electric power steering system

Abstract

The present invention discloses a method for estimating the zero position of a steering wheel applied to a redundant electric power steering system, which includes the following steps: Step 1: After the system is powered on, the battery charges the small battery through the charging chip of System A and supplies power to the power management module of System A. The power management module of System A supplies power to the control module and the motor position sensor. In the present invention, by converting the relative rotation angle recorded by the motor position sensor into an absolute rotation angle to replace the torque angle sensor TAS to record the absolute rotation angle of the steering wheel, and redundant the motor position sensor. After the system is powered off, the motor position sensor enters the low-power mode, and the small battery supplies power to the rotor revolution recording module of the motor position sensor, which can maintain the angle information recording function, and the MCU interacts with the absolute rotation angle information of the steering wheel, enabling it to work alternately after the system is powered off; while reducing the usage cost, the accuracy of the angle information and the reliability of the system are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of steering systems, and particularly to a method for estimating the zero position of a steering wheel applied to a redundant electric power steering system. Background Art

[0002] With the gradual maturity of the electric power steering system EPS technology, the absolute steering wheel angle signal in EPS has become increasingly important; the absolute steering wheel angle signal is not only used for its own function, but also transmitted to other vehicle modules through communication; therefore, it is of great significance for the safety of the steering system and the vehicle.

[0003] The traditional corner recording system uses a torque angle sensor TAS to record the absolute angle of the steering wheel, and only a single motor position sensor is used in the redundant control unit to record the angle information; this method of using the torque angle sensor TAS to record the angle has a high cost, and the motor position sensor will increase the risk of failure when recording the angle information for a long time. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for estimating the zero position of a steering wheel applied to a redundant electric power steering system to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A method for estimating the zero position of a steering wheel applied to a redundant electric power steering system, including the following steps:

[0006] Step 1: After the system is powered on, the battery charges the small battery through the A-system charging chip and supplies power to the A-system power management module, and the A-system power management module supplies power to the control module and the motor position sensor; the battery charges the small battery through the B-system charging chip and supplies power to the B-system power management module, and the B-system power management module supplies power to the control module and the motor position sensor;

[0007] Step 2: When the A / B-system control module is powered on, determine whether the A / B-system motor position sensor is powered on for the first time; when it is determined that the A / B-system motor position sensor is powered on for the first time, jump to Step 3; when it is determined that the A / B-system motor position sensor is not powered on for the first time, jump to Step 4;

[0008] Step 3: The absolute steering wheel angle calculation module of the A / B-system motor position sensor performs zero position calibration of the steering wheel, and the A-system motor position sensor records the angle information, where the internal composition and functional roles of the A / B-system are exactly the same;

[0009] Step 4: The A / B-system MCU exchanges the absolute steering wheel angle information through the CAN transceiver TJA1051TK / 3, and the system runs and works normally;

[0010] Step 5: Power off the system and determine whether the angle information was recorded by the motor position sensor of System A before the previous power-off.

[0011] Step 6: When it is determined that the angle information was recorded by the motor position sensor of System A before the previous power-off, jump to Step 7; when it is determined that the angle information was not recorded by the motor position sensor of System A before the previous power-off, jump to Step 8.

[0012] Step 7: Power off the motor position sensor of System A, the motor position sensor of System B enters the low-power mode, only the rotor revolution counting module works, and the small battery of System B supplies power to the rotor revolution counting module of the motor position sensor through a buck chip.

[0013] Step 8: The motor position sensor of System A enters the low-power mode, only the rotor revolution counting module works, power off the motor position sensor of System B, and the small battery of System A supplies power to the rotor revolution counting module of the motor position sensor through a buck chip.

[0014] Step 9: The power management module of System A stops supplying power to the motor position sensor, and the power management module of System B stops supplying power to the motor position sensor.

[0015] Preferably, in Step 1, the storage battery charges the small battery through the charging chips of System A / B respectively. After the system is powered off, the small batteries of System A / B supply power to the rotor revolution counting module of the motor position sensor through buck chips respectively.

[0016] Preferably, in Step 3, when the motor position sensor of System A / B is powered on for the first time, the absolute steering wheel angle calibration is performed by the absolute angle calculation module of System A / B, and the motor position sensor of System A records the angle information.

[0017] Preferably, in Step 4, when the motor position sensor of System A / B is not powered on for the first time, the MCU of System A / B exchanges the absolute steering wheel angle information, and the system works normally.

[0018] Preferably, in Step 7, when the angle information was recorded by the motor position sensor of System A before the previous power-off, the motor position sensor of System A is powered off during this power-off, the motor position sensor of System B enters the low-power mode, only the rotor revolution counting module works, and the small battery of System B supplies power to the rotor revolution counting module of the motor position sensor through a buck chip.

[0019] Preferably, in the eighth step, if the non-A system motor position sensor records the angular information before the previous power-off, then when powering off this time, the A system motor position sensor enters the low-power mode, only the rotor revolution counting module works, the B system motor position sensor is powered off, and the small battery of the A system supplies power to the rotor revolution counting module of the motor position sensor through a buck chip.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] The present invention converts the relative rotation angle recorded by the motor position sensor into an absolute rotation angle to replace the torque angle sensor TAS to record the absolute rotation angle of the steering wheel, and redundant the motor position sensor. After the system is powered off, the motor position sensor enters the low-power mode, and the small battery supplies power to the rotor revolution counting module of the motor position sensor, which can maintain the angle information recording function, and the MCU interacts with the absolute rotation angle information of the steering wheel to make it work alternately after the system is powered off; while reducing the use cost, it ensures the accuracy of the angle information and the reliability of the system. Description of the Drawings

[0022] Figure 1 is the flowchart of the present invention;

[0023] Figure 2 is the functional block diagram of the present invention;

[0024] Figure 3 is the charging and discharging circuit diagram of the small battery of the present invention. Detailed Embodiments

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] Please refer to Figures 1-3 , the present invention provides a technical solution: a steering wheel zero position estimation method applied to a redundant electric power steering system, including the following steps:

[0027] Step 1: After the system is powered on, the battery charges the small battery through the A system charging chip and supplies power to the A system power management module. The A system power management module supplies power to the control module and the motor position sensor; the battery charges the small battery through the B system charging chip and supplies power to the B system power management module. The B system power management module supplies power to the control module and the motor position sensor;

[0028] Step 2: After the A / B system control module is powered on, determine whether the A / B system motor position sensor is powered on for the first time; if it is determined that the A / B system motor position sensor is powered on for the first time, jump to Step 3; if it is determined that the A / B system motor position sensor is not powered on for the first time, jump to Step 4;

[0029] Step 3: The A / B system motor position sensor absolute rotation angle calculation module performs steering wheel zero position calibration, and the A system motor position sensor records angle information, where the internal composition and functional roles of the A / B system are exactly the same;

[0030] Step 4: The A / B system MCU exchanges the absolute rotation angle information of the steering wheel through the CAN transceiver TJA1051TK / 3, and the system runs and works normally;

[0031] Step 5: When the system is powered off, determine whether the angle information was recorded by the A system motor position sensor before the previous power-off;

[0032] Step 6: If it is determined that the angle information was recorded by the A system motor position sensor before the previous power-off, jump to Step 7; if it is determined that the angle information was not recorded by the A system motor position sensor before the previous power-off, jump to Step 8;

[0033] Step 7: The A system motor position sensor is powered off, and the B system motor position sensor enters the low-power mode. Only the rotor revolution counting module works, and the B system small battery supplies power to the rotor revolution counting module of the motor position sensor through a step-down chip;

[0034] Step 8: The A system motor position sensor enters the low-power mode. Only the rotor revolution counting module works, and the B system motor position sensor is powered off. The A system small battery supplies power to the rotor revolution counting module of the motor position sensor through a step-down chip;

[0035] Step 9: The A system power management module stops supplying power to the motor position sensor, and the B system power management module stops supplying power to the motor position sensor.

[0036] In the above Step 1, the storage battery charges the small battery through the A / B system charging chip respectively. After the system is powered off, the A / B system small batteries supply power to the rotor revolution counting module of the motor position sensor through the step-down chip respectively.

[0037] In the above Step 3, when the A / B system motor position sensor is powered on for the first time, the A / B system absolute rotation angle calculation module performs steering wheel zero position calibration, and the A system motor position sensor records angle information.

[0038] In the fourth step, when the A / B system motor position sensor is not powered on for the first time, the A / B system MCU exchanges the absolute steering wheel angle information and the system works normally.

[0039] In the seventh step, if the A system motor position sensor recorded the angle information before the previous power-off, then when powering off this time, the A system motor position sensor is powered off, the B system motor position sensor enters the low-power mode, only the rotor revolution recording module works, and the B system small battery supplies power to the rotor revolution recording module of the motor position sensor through a buck chip.

[0040] In the eighth step, if the angle information was not recorded by the A system motor position sensor before the previous power-off, then when powering off this time, the A system motor position sensor enters the low-power mode, only the rotor revolution recording module works, the B system motor position sensor is powered off, and the A system small battery supplies power to the rotor revolution recording module of the motor position sensor through a buck chip.

[0041] It should 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 actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are 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.

[0042] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A steering wheel zero position estimation method applied to a redundant electric power steering system, characterized in that: The steps include: Step 1: After the system is powered on, the battery charges the small battery through the A system charging chip, and supplies power to the A system power management module, and the A system power management module supplies power to the control module and the motor position sensor; the battery charges the small battery through the B system charging chip, and supplies power to the B system power management module, and the B system power management module supplies power to the control module and the motor position sensor; Step 2: After the A / B system control module is powered on, determine whether the A / B system motor position sensor is powered on for the first time; if it is determined that the A / B system motor position sensor is powered on for the first time, jump to step 3; If it is determined that the A / B system motor position sensor is not powered on for the first time, jump to step 4; Step 3: The absolute angle calculation module of the motor position sensor of the A / B system performs steering wheel zero position calibration, and the motor position sensor of the A system records the angle information. The internal structure and functions of the A / B system are exactly the same; Step 4: The A / B system MCU exchanges the steering wheel absolute angle information through the CAN transceiver TJA1051TK / 3, and the system runs and works normally; Step 5: Power off the system and determine whether the motor position sensor of system A recorded angle information before the last power off. Step 6: If it is determined that the angle information was recorded by the motor position sensor of system A before the last power-off, jump to step 7; if it is determined that the angle information was not recorded by the motor position sensor of system A before the last power-off, jump to step 8; Step 7: The motor position sensor of system A is powered off, and the motor position sensor of system B enters low power consumption mode. Only the rotor revolution recording module works. The small battery of system B supplies power to the rotor revolution recording module of the motor position sensor through the step-down chip. Step 8: The motor position sensor of system A enters low power consumption mode, and only the rotor revolution recording module works. The motor position sensor of system B is powered off, and the small battery of system A supplies power to the rotor revolution recording module of the motor position sensor through the step-down chip. Step nine: The power management module of system A stops supplying power to the motor position sensor, and the power management module of system B stops supplying power to the motor position sensor.

2. The method for estimating the zero position of a steering wheel applied to a redundant electric power steering system according to claim 1, characterized in that: In the step 1, the storage battery charges the small battery through the A / B system charging chip respectively. When the system is powered off, the A / B system small battery supplies power to the motor position sensor rotor revolution recording module through the step-down chip respectively.

3. The method for estimating the zero position of a steering wheel applied to a redundant electric power steering system according to claim 2, characterized in that: In the step three, when the A / B system motor position sensor is powered on for the first time, the A / B system absolute angle calculation module performs steering wheel zero position calibration, and the A system motor position sensor records angle information.

4. The method for estimating the zero position of a steering wheel applied to a redundant electric power steering system according to claim 3, characterized in that: In the step 4, when the A / B system motor position sensor is not powered on for the first time, the A / B system MCU exchanges the steering wheel absolute angle information, and the system works normally.

5. The method for estimating zero position of a steering wheel applied to a redundant electric power steering system according to claim 4, characterized in that: In step seven, when the motor position sensor of system A recorded the angle information before the last power-off, the motor position sensor of system A is powered off during this power-off, and the motor position sensor of system B enters a low power consumption mode, with only the rotor revolution recording module working, and the small battery of system B supplies power to the rotor revolution recording module of the motor position sensor through the step-down chip.

6. The method for estimating the zero position of a steering wheel applied to a redundant electric power steering system according to claim 5, characterized in that: In step eight, when the motor position sensor of the non-system A recorded angle information before the last power-off, the motor position sensor of the system A enters a low power consumption mode during this power-off, and only the rotor revolutions recording module works. The motor position sensor of the system B is powered off, and the small battery of the system A supplies power to the rotor revolutions recording module of the motor position sensor through the step-down chip.

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