A car ESC controller hill start control system and method and a car

Abstract

This invention discloses a hill start control system and method for an automotive ESC controller, and an automotive vehicle, belonging to the field of vehicle engineering technology. In the system, a brake master cylinder hydraulic pressure sensor is installed in the brake master cylinder to monitor the brake hydraulic pressure value P1 applied by the driver; a hydraulic pressure sensor is installed in the HU actuator to monitor the wheel cylinder hydraulic pressure value P2; a longitudinal acceleration sensor is used to monitor the slope value of the vehicle's parking ramp; the ECU processor calculates the wheel cylinder hydraulic pressure value P3 based on the slope value of the vehicle's parking ramp; when the brake hydraulic pressure value P1 ≥ the wheel cylinder hydraulic pressure value P3, it is considered that there is no risk of the vehicle rolling backward, and the ECU processor does not issue a pressurization command to the HU actuator; when the brake hydraulic pressure value P1 < the wheel cylinder hydraulic pressure value P3, it is determined that there is a risk of the vehicle rolling backward, and the ECU processor controls the HU actuator to pressurize the wheel cylinders; when the monitored wheel cylinder hydraulic pressure value P2 reaches the wheel cylinder hydraulic pressure value P3, pressurization stops.

Description

Technical Field

[0001] This invention belongs to the field of vehicle engineering technology, specifically relating to a car ESC controller hill start control system and method, and a car. Background Technology

[0002] When a car is going uphill, after the driver stops by pressing the brake pedal, the hill start function in the ESC controller prevents the vehicle from rolling backward for a certain period of time after the driver releases the brake pedal. However, regardless of the reason, if the force applied to the brake pedal is too small (small pedal force, low oil pressure, and low pressure holding during hill start), the car will not be able to stay stationary within the specified time after the brake pedal is released and will roll backward.

[0003] The prior art provides a hill start assist method, and the invention patent with authorization announcement number CN104755342 B is to sense the hill start intention by the vehicle controller and convert the sensed hill resistance into target torque. The controller enables the engine to have sufficient torque reserve in advance. However, the vehicle controller often misjudges the hill start intention and cannot completely avoid the problem of the vehicle rolling back when parking on a slope. In addition, its structure is complex and cannot be widely applied.

[0004] In summary, existing technologies suffer from the problem of vehicles rolling backwards when stopped on slopes due to the extremely low braking force, resulting in low hydraulic pressure during hill starts and causing the vehicle to roll backwards when the vehicle's condition and operating environment momentarily exceed acceptable limits. Summary of the Invention

[0005] The purpose of this invention is to provide a hill start control system and method for an automotive ESC controller, as well as an automotive vehicle, to solve the problem in the prior art where, when a vehicle is parked on a slope, the low oil pressure generated due to very small brake pedal input force leads to insufficient oil pressure for hill start maintenance, causing the vehicle to roll back when the vehicle's condition and operating environment momentarily exceed acceptable limits. This invention prevents the vehicle from rolling back when starting on a slope, regardless of whether the driver is intentionally, unintentionally, or due to personal reasons unable to apply sufficient pedal force to maintain adequate oil pressure.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A hill start control system for an automotive ESC controller includes a brake master cylinder hydraulic pressure sensor, a hydraulic pressure sensor, a longitudinal acceleration sensor, a HU actuator, and an ECU processor.

[0008] The brake master cylinder hydraulic pressure sensor is installed inside the brake master cylinder to monitor the brake hydraulic pressure value P1 applied by the driver.

[0009] The oil pressure sensor is installed inside the HU actuator to monitor the wheel cylinder oil pressure value P2;

[0010] The longitudinal acceleration sensor is used to monitor the slope value of the vehicle parking ramp;

[0011] The brake master cylinder oil pressure sensor, oil pressure sensor, longitudinal acceleration sensor are connected to the ECU processor for data transmission;

[0012] The ECU processor calculates the wheel cylinder oil pressure value P3 based on the slope value of the vehicle parking ramp.

[0013] When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that there is no risk of the car rolling backward, and the ECU processor does not issue a pressurization command to the HU actuator.

[0014] When the brake fluid pressure P1 is less than the wheel cylinder fluid pressure P3, it is determined that the car is at risk of rolling backward. The ECU processor controls the HU actuator to pressurize the wheel cylinder. When the monitored wheel cylinder fluid pressure P2 reaches the wheel cylinder fluid pressure P3, the pressurization stops.

[0015] Preferably, the ECU processor is equipped with a comparator module, which is used to compare the brake oil pressure value P1 and the wheel cylinder oil pressure value P3. Based on the comparison result output by the comparator module, the ECU processor controls the HU actuator.

[0016] Preferably, the longitudinal acceleration sensor is installed inside the passenger compartment.

[0017] Preferably, the wheel cylinder oil pressure value P3 is the limit value required for the vehicle to stop on the current slope under full load.

[0018] Preferably, the ECU processor controls the drive motor in the HU actuator to pressurize the four wheel cylinders and increase the oil pressure value P2 of the wheel cylinders.

[0019] Preferably, the brake master cylinder oil pressure sensor is selected from one or two of semiconductor piezoresistive sensors, elastic strain sensors, thick-film pressure sensors, and ceramic piezoresistive sensors.

[0020] Preferably, the longitudinal acceleration sensor is selected from one of the following: piezoelectric longitudinal acceleration sensor, piezoresistive longitudinal acceleration sensor, capacitive longitudinal acceleration sensor, or resonant longitudinal acceleration sensor.

[0021] A hill start control method for an automotive ESC controller, comprising,

[0022] The brake master cylinder hydraulic pressure sensor installed in the brake master cylinder monitors the brake hydraulic pressure value P1 applied by the driver, the hydraulic pressure sensor installed in the HU actuator monitors the wheel cylinder hydraulic pressure value P2, and the longitudinal acceleration sensor monitors the vehicle parking slope value. The brake hydraulic pressure value P1, the wheel cylinder hydraulic pressure value P2, and the vehicle parking slope value are all transmitted to the ECU processor. The ECU processor calculates the wheel cylinder hydraulic pressure value P3 required for the vehicle to stop on the current slope based on the vehicle parking slope value monitored by the longitudinal acceleration sensor.

[0023] When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that there is no risk of the car rolling backward, and the ECU processor does not issue a pressurization command to the HU actuator.

[0024] When the brake fluid pressure P1 is less than the wheel cylinder fluid pressure P3, it is determined that the car is at risk of rolling backward. The ECU processor controls the HU actuator to pressurize the wheel cylinder. When the monitored wheel cylinder fluid pressure P2 reaches the wheel cylinder fluid pressure P3, the pressurization stops.

[0025] Preferably, the formula for calculating the wheel cylinder hydraulic pressure value P3 is:

[0026] P3=(G*sin(A X )*g*R j *10 6 ) / [π*(D f 2 *μ f *R f +D R 2 *μ R *R R )]

[0027] Where G is the vehicle weight, in kg; A X The slope value is in degrees; g is the deceleration due to gravity, taken as 10.0 m / s². 2 ;R j D is the tire's static load radius, in mm. f The diameter of the front wheel piston is in mm; μ f R is the coefficient of friction of the front friction plate. f D is the effective radius of the front brake disc, in mm. R The diameter of the rear wheel piston is in mm; μ R R is the coefficient of friction of the rear friction plate. R The effective radius of the rear brake disc is in mm.

[0028] A car equipped with a hill start control system for an ESC controller as described in any one of the above-mentioned claims.

[0029] Compared with the prior art, the present invention has the following beneficial technical effects:

[0030] This invention provides a hill start control system for an automotive ESC controller. The ESC controller's ECU calculates the braking force required for a fully loaded vehicle at a given slope based on the gradient detected by a longitudinal acceleration sensor. This braking force is then converted into the required master cylinder hydraulic pressure. This pressure is compared with the actual measured master cylinder hydraulic pressure at that slope. If the detected master cylinder hydraulic pressure is lower than the theoretically calculated pressure, the ESC automatically increases the pressure to the theoretically calculated pressure. This avoids the problem of vehicle rollback when the actual input hydraulic pressure is too low (i.e., insufficient pressure holding during hill starts) and when the vehicle's condition or operating environment momentarily exceeds tolerances. This invention requires no additional hardware; only adjustments to the ESC controller's control strategy are needed. It is low-cost, highly operable, and safe and reliable. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a car ESC controller hill start control system according to Embodiment 1 of the present invention.

[0032] Figure 2 This is a flowchart illustrating an ESC controller hill start control method according to Embodiment 2 of the present invention.

[0033] In the attached diagram: 1 is the brake master cylinder hydraulic pressure sensor; 2 is the hydraulic pressure sensor; 3 is the longitudinal acceleration sensor; 4 is the HU actuator; 5 is the ECU processor. Detailed Implementation

[0034] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0035] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0037] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0039] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0040] Example 1

[0041] The present invention provides a hill start control system for an automotive ESC controller, comprising a brake master cylinder hydraulic pressure sensor 1, a hydraulic pressure sensor 2, a longitudinal acceleration sensor 3, a HU actuator 4, and an ECU processor 5.

[0042] The brake master cylinder oil pressure sensor 1 is installed in the brake master cylinder to monitor the brake oil pressure value P1 applied by the driver.

[0043] The oil pressure sensor 2 is installed inside the HU actuator 4 to monitor the wheel cylinder oil pressure value P2;

[0044] The longitudinal acceleration sensor 3 is used to monitor the slope value of the vehicle parking ramp;

[0045] The brake master cylinder oil pressure sensor 1, oil pressure sensor 2, and longitudinal acceleration sensor 3 are connected to the ECU processor 5 for data transmission.

[0046] The ECU processor 5 calculates the wheel cylinder oil pressure value P3 based on the slope value of the vehicle parking ramp.

[0047] The formula for calculating the wheel cylinder hydraulic pressure value P3 is as follows:

[0048] P3=(G*sin(A X )*g*R j *10 6 ) / [π*(D f 2 *μ f *R f +D R 2 *μ R *R R )]

[0049] In the formula: G is the vehicle weight (fully loaded), in kg;

[0050] A X This is the slope value, in degrees;

[0051] g is the deceleration due to gravity, which is taken as 10.0 m / s² in this embodiment. 2 ;

[0052] R j This is the tire's static load radius, in mm.

[0053] D f This refers to the diameter of the front wheel piston, in mm.

[0054] μ f The coefficient of friction of the front friction plate;

[0055] R f The effective radius of the front brake disc is in mm.

[0056] D R This refers to the diameter of the rear wheel piston, in mm.

[0057] μ R The coefficient of friction of the rear friction plate;

[0058] R R The effective radius of the rear brake disc is in mm.

[0059] When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that there is no risk of the car rolling backward, and the ECU processor 5 does not issue a pressurization command to the HU actuator 4.

[0060] When the brake oil pressure value P1 is less than the wheel cylinder oil pressure value P3, it is determined that the car is at risk of rolling backward. The ECU processor 5 controls the HU actuator 4 to pressurize the wheel cylinder. When the monitored wheel cylinder oil pressure value P2 reaches the wheel cylinder oil pressure value P3, the pressurization stops.

[0061] In this embodiment of the invention, a comparator module is also included, which is used to compare the brake oil pressure value P1 and the wheel cylinder oil pressure value P3, and output the comparison result.

[0062] In this embodiment of the invention, the main functions of the ECU processor 5 include: 1) receiving the parking slope of the vehicle from the longitudinal acceleration sensor and calculating the brake oil pressure value required for the vehicle to stop at that slope; 2) receiving the actual oil pressure value of the brake master cylinder when the vehicle stops; 3) receiving the oil pressure value of the pressure sensor inside the actuator; 4) determining whether to instruct the actuator to add oil based on the calculated required oil pressure value, the measured oil pressure value of the brake master cylinder and the oil pressure value inside the actuator.

[0063] The function of brake master cylinder oil pressure sensor 1 is to monitor the actual oil pressure P1 of the brake master cylinder.

[0064] The function of oil pressure sensor 2 is to monitor the oil pressure value P2 inside the actuator.

[0065] The function of longitudinal acceleration sensor 3 is to monitor the actual slope value of the car.

[0066] The function of HU actuator 4 is to execute ECU processor instructions to pressurize the wheel cylinder.

[0067] Example 2

[0068] Figure 1 This is a schematic diagram of a car ESC controller hill start control system according to an embodiment of the present invention. Figure 1 The ESC controller hill start control system shown includes: brake master cylinder oil pressure sensor 1, oil pressure sensor 2, longitudinal acceleration sensor 3, HU actuator 4, and ECU processor 5.

[0069] The outputs of the brake master cylinder oil pressure sensor 1, oil pressure sensor 2 and longitudinal acceleration sensor 3 are all connected to the input of the ECU processor 5, and the output of the ECU processor 5 is connected to the input of the HU actuator 4.

[0070] The brake master cylinder oil pressure sensor 1 is installed inside the brake master cylinder and is used to monitor the brake oil pressure value P1 applied by the driver.

[0071] The hydraulic pressure sensor 2 is installed inside the HU actuator and is used to monitor the oil pressure value P2 of the wheel cylinder.

[0072] The longitudinal acceleration sensor 3 is used to monitor the slope value of the parking ramp, and these signals are transmitted to the ECU processor 5. Based on the slope value of the parking ramp monitored by the longitudinal acceleration sensor 3, the ECU processor 5 calculates and estimates the wheel cylinder oil pressure value P3 required for the car to stop on the slope under full load.

[0073] The formula for calculating the wheel cylinder hydraulic pressure value P3 is as follows:

[0074] P3=(G*sin(A X )*g*R j *10 6 ) / [π*(D f 2 *μ f *R f +D R 2 *μ R *R R )]

[0075] In the formula: G is the vehicle weight (fully loaded), in kg;

[0076] A X This is the slope value, in degrees;

[0077] g is the deceleration due to gravity, which is taken as 10.0 m / s² in this embodiment. 2 ;

[0078] R j This is the tire's static load radius, in mm.

[0079] D f This refers to the diameter of the front wheel piston, in mm.

[0080] μ f The coefficient of friction of the front friction plate;

[0081] R f The effective radius of the front brake disc is in mm.

[0082] D R This refers to the diameter of the rear wheel piston, in mm.

[0083] μ R The coefficient of friction of the rear friction plate;

[0084] R R The effective radius of the rear brake disc is in mm.

[0085] When the brake oil pressure value P1 is less than the wheel cylinder oil pressure value P3, it is determined that the car is at risk of rolling backward. Therefore, a command is issued to the HU actuator 4 to pressurize the wheel cylinder. When the monitored wheel cylinder oil pressure value P2 reaches the wheel cylinder oil pressure value P3, the pressurization is stopped.

[0086] When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that there is no risk of the car rolling backward, and the ECU processor 5 does not issue a pressurization command to the HU actuator 4.

[0087] In this embodiment of the invention, the ECU processor 5 is provided with a comparator module, which is used to compare the brake oil pressure value P1 and the wheel cylinder oil pressure value P3. Based on the comparison result output by the comparator module, the ECU processor 5 controls the HU actuator 4.

[0088] In this embodiment of the invention, the brake master cylinder oil pressure sensor 1 and oil pressure sensor 2 may be selected from one or two of semiconductor piezoresistive sensors, elastic strain sensors, thick film pressure sensors and ceramic piezoresistive sensors.

[0089] In this embodiment of the invention, the longitudinal acceleration sensor 3 may be selected from one of the following: piezoelectric longitudinal acceleration sensor, piezoresistive longitudinal acceleration sensor, capacitive longitudinal acceleration sensor, or resonant longitudinal acceleration sensor.

[0090] In this embodiment of the invention, the longitudinal acceleration sensor 3 can accurately measure the slope value of the parking ramp by measuring the component of gravitational acceleration in the axial direction of the acceleration sensor.

[0091] A longitudinal accelerometer measures the slope of a parking ramp, i.e., the car's tilt angle, based on the component of gravitational acceleration along the sensor's axis. When a car tilts, the direction of gravitational acceleration changes accordingly, and the longitudinal accelerometer detects this change. When the car tilts, longitudinal gravitational acceleration produces components along different axes of the accelerometer. For example, in a dual-axis (XY) accelerometer, gravitational acceleration produces components along both the X and Y axes. By measuring these components, the car's tilt angle, i.e., the parking ramp slope, can be calculated. Specifically, if the components of gravitational acceleration along the X and Y axes (Ax and Ay) are known, the tilt angle α can be calculated using the arctangent function, i.e., α = arctan(Ax / Ay).

[0092] Example 3

[0093] An embodiment of the present invention provides a hill start control method for an automotive ESC controller, comprising the following processes:

[0094] The brake master cylinder hydraulic pressure sensor 1, installed in the brake master cylinder, monitors the brake hydraulic pressure value P1 applied by the driver; the hydraulic pressure sensor 2, installed in the HU actuator, monitors the wheel cylinder hydraulic pressure value P2; and the longitudinal acceleration sensor 3, located in the passenger compartment, monitors the vehicle's parking ramp gradient value A. XThese signals are all transmitted to the ECU processor 5. Among them, the parking ramp gradient value A, monitored by the longitudinal acceleration sensor 3, is... X After logical calculation by the ECU processor, the required wheel cylinder oil pressure value P3 for the car to stop on the slope when fully loaded is calculated.

[0095] The formula for calculating the wheel cylinder hydraulic pressure value P3 is as follows:

[0096] P3=(G*sin(A X )*g*R j *10 6 ) / [π*(D f 2 *μ f *R f +D R 2 *μ R *R R )]

[0097] In the formula: G is the vehicle weight (fully loaded), in kg;

[0098] A X This is the slope value, in degrees;

[0099] g is the deceleration due to gravity, which is taken as 10.0 m / s² in this embodiment. 2 ;

[0100] R j This is the tire's static load radius, in mm.

[0101] D f This refers to the diameter of the front wheel piston, in mm.

[0102] μ f The coefficient of friction of the front friction plate;

[0103] R f The effective radius of the front brake disc is in mm.

[0104] D R This refers to the diameter of the rear wheel piston, in mm.

[0105] μ R The coefficient of friction of the rear friction plate;

[0106] R R The effective radius of the rear brake disc is in mm.

[0107] Figure 2It is a schematic diagram of the control strategy for the ramp start function of an ESC controller according to the present invention. The ECU processor 5 makes a logical comparison between P1 and P3. If P1 < P3, it is considered that the vehicle has a risk of rolling back. Then, an instruction is sent to the HU actuator 4 to pressurize the wheel cylinder, that is, the ECU processor 5 turns on the drive motor in the HU actuator 4, and the four-wheel pipeline is pressurized by the motor. When the monitored P2 value reaches the P3 value, the pressurization is stopped. This process is a closed-loop process.

[0108] If P1 ≥ P3, it is considered that the vehicle has no risk of rolling back, and the ECU processor 5 does not send a pressurization instruction to the HU actuator 4.

[0109] It should be noted that the P3 value is an upper limit target value (the value under the most severe conditions, such as full load) to ensure that the vehicle does not roll back on a certain slope. However, it must be ensured that when applying an extremely small pedal force, the vehicle can park on the slope, and after releasing the brake pedal, the ramp start function can maintain the pressure P3 to ensure no rolling back.

[0110] The embodiment of the present invention provides a vehicle, on which the above-mentioned ramp start control system of an automotive ESC controller is installed. By applying the ramp start control system of an automotive ESC controller in the embodiment of the present invention, the vehicle can avoid the problem of the vehicle rolling back when the actual input oil pressure is too low, that is, the ramp start pressure maintaining is too low, and the vehicle state and the use environment are instantaneously extremely poor. The strategy of the ramp start function of an automotive ESC controller of the present invention. The present invention does not require additional hardware, only needs to adjust the strategy of the ESC controller, so it has low cost, strong operability, and is safe and reliable.

[0111] The above shows and describes the basic principles, main features and advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0112] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A hill start control system for an automotive ESC controller, characterized in that, Includes brake master cylinder oil pressure sensor (1), oil pressure sensor (2), longitudinal acceleration sensor (3), HU actuator (4), and ECU processor (5); The brake master cylinder oil pressure sensor (1) is installed in the brake master cylinder to monitor the brake oil pressure value P1 applied by the driver; The oil pressure sensor (2) is installed inside the HU actuator (4) to monitor the oil pressure value P2 of the wheel cylinder; The longitudinal acceleration sensor (3) is used to monitor the slope value of the parking ramp; The brake master cylinder oil pressure sensor (1), oil pressure sensor (2), and longitudinal acceleration sensor (3) are connected to the ECU processor (5) for data transmission; The ECU processor (5) calculates the wheel cylinder oil pressure value P3 based on the slope value of the vehicle parking ramp; When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that the car has no risk of rolling backward, and the ECU processor (5) does not issue a pressurization command to the HU actuator (4). When the brake oil pressure value P1 < the wheel cylinder oil pressure value P3, it is determined that the car is at risk of rolling backward. The ECU processor (5) controls the HU actuator (4) to pressurize the wheel cylinder. When the monitored wheel cylinder oil pressure value P2 reaches the wheel cylinder oil pressure value P3, the pressurization stops.

2. The automobile ESC controller hill start control system according to claim 1, characterized in that, The ECU processor (5) is equipped with a comparator module, which is used to compare the brake oil pressure value P1 and the wheel cylinder oil pressure value P3. Based on the comparison result output by the comparator module, the ECU processor (5) controls the HU actuator (4).

3. The automobile ESC controller hill start control system according to claim 1, characterized in that, The longitudinal acceleration sensor (3) is installed inside the passenger cabin.

4. The automobile ESC controller hill start control system according to claim 1, characterized in that, The wheel cylinder oil pressure value P3 is the limit value required for the vehicle to stop on the current slope when fully loaded.

5. A hill start control system for an automotive ESC controller according to claim 1, characterized in that, The ECU processor (5) controls the drive motor in the HU actuator (4) to pressurize the four wheel cylinders and increase the oil pressure value P2 of the wheel cylinders.

6. A car ESC controller hill start control system according to claim 1, characterized in that, The brake master cylinder oil pressure sensor (1) and oil pressure sensor (2) are selected from one or two of semiconductor piezoresistive sensors, elastic strain sensors, thick film pressure sensors and ceramic piezoresistive sensors.

7. A car ESC controller hill start control system according to claim 1, characterized in that, The longitudinal acceleration sensor (3) is selected from one of the following: piezoelectric longitudinal acceleration sensor, piezoresistive longitudinal acceleration sensor, capacitive longitudinal acceleration sensor or resonant longitudinal acceleration sensor.

8. A hill start control method for an automotive ESC controller, characterized in that, include, The brake master cylinder hydraulic pressure sensor (1) installed in the brake master cylinder monitors the brake hydraulic pressure value P1 applied by the driver, the hydraulic pressure sensor (2) installed in the HU actuator monitors the wheel cylinder hydraulic pressure value P2, and the longitudinal acceleration sensor (3) monitors the vehicle parking slope value. The brake hydraulic pressure value P1, the wheel cylinder hydraulic pressure value P2 and the vehicle parking slope value are all transmitted to the ECU processor (5). The ECU processor (5) calculates the wheel cylinder hydraulic pressure value P3 required for the vehicle to stop on the current slope based on the vehicle parking slope value monitored by the longitudinal acceleration sensor (3). When the brake oil pressure value P1 is greater than or equal to the wheel cylinder oil pressure value P3, it is considered that the car has no risk of rolling backward, and the ECU processor (5) does not issue a pressurization command to the HU actuator (4). When the brake oil pressure value P1 < the wheel cylinder oil pressure value P3, it is determined that the car is at risk of rolling backward. The ECU processor (5) controls the HU actuator (4) to pressurize the wheel cylinder. When the monitored wheel cylinder oil pressure value P2 reaches the wheel cylinder oil pressure value P3, the pressurization stops.

9. A hill start control method for an automotive ESC controller according to claim 8, characterized in that, The formula for calculating the cylinder hydraulic pressure value P3 is as follows: P3=(G*sin(A X )*g*R j *10 6 ) / [π*(D f 2 *m f *R f +D R 2 *m R *R R )] Where G is the vehicle weight, in kg; A X The slope value is in degrees; g is the deceleration due to gravity, taken as 10.0 m / s². 2 ;R j D is the tire's static load radius, in mm. f The diameter of the front wheel piston is in mm; μ f R is the coefficient of friction of the front friction plate. f D is the effective radius of the front brake disc, in mm. R The diameter of the rear wheel piston is in mm; μ R R is the coefficient of friction of the rear friction plate. R The effective radius of the rear brake disc is in mm.

10. A car, characterized in that, An automotive ESC controller hill start control system according to any one of claims 1 to 7 is installed.

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