Vehicle Control System

Abstract

To provide a vehicle control system which can prevent occurrence of noise and vibration in a pressing control, and improve responsiveness of a brake.SOLUTION: A vehicle control system 1 comprises: a torque calculation part 102 which calculates torque to reduce backlash of a gear of a vehicle; a braking force calculation part 103 which calculates braking force requesting to a brake by use of the torque; a motor control part 104 which controls a motor based on the torque; and a brake control part 202 which controls the brake based on the braking force. The braking force calculation part 103 calculates request braking force by multiplying the torque and parameter, and calculates upper limit value of the braking force by multiplying the torque and a prescribed rate. The brake control part 202 controls the brake based on the braking force in which the upper limit value is an upper limit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle control system for controlling a vehicle. [Background technology]

[0002] Conventionally, in vehicles equipped with a motor, such as hybrid electric vehicles (HEVs), a pressing control is performed in which the motor outputs torque to eliminate gear backlash in order to prevent gear rattle noise that can occur when the vehicle starts moving.

[0003] As an example of such pressing control, the invention disclosed in Patent Document 1 applies rate processing to the requested reflection rate to calculate a target reflection rate, and multiplies the target reflection rate by the basic braking force to output the target braking force to the brake. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-114929 Summary of the Invention [Problem to be solved by the invention]

[0005] In this type of pressing control, there is a delay between when braking force is requested from the brake and when effective braking force is generated. In order to improve this brake responsiveness, the invention disclosed in Patent Document 1 considers increasing the value of the target reflection rate and outputting a large braking force to the brake. However, outputting excessive braking force to the brake poses a problem in that noise and vibration such as hydraulic pulsation are generated by the hydraulic brake.

[0006] In order to solve the above problems, an object of the present invention is to provide a vehicle control system that can prevent the generation of noise and vibration during pressing control and improve brake responsiveness. [Means for solving the problem]

[0007] A vehicle control system for controlling a vehicle equipped with a motor and a brake according to one aspect of the present invention includes: a torque calculation unit that calculates a torque for eliminating backlash in a gear provided in the vehicle; a braking force calculation unit that calculates a braking force required of the brake using the torque; a motor control unit that controls the motor based on the torque; a brake control unit that controls the brakes based on the braking force; Including, The braking force calculation unit The required braking force is calculated by multiplying the torque by a parameter. The upper limit of the braking force is calculated by multiplying the torque by a predetermined rate. The brake control unit controls the brakes based on the braking force up to the upper limit value. [Effects of the Invention]

[0008] The present invention can provide a vehicle control system that can prevent noise and vibration from occurring during pressing control and improve brake response. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of a vehicle control system according to an aspect of the present invention. [Figure 2] 1 is a block diagram showing a configuration of a motor control device according to an aspect of the present invention; [Figure 3] 1 is a block diagram showing a configuration of a brake control device according to one aspect of the present invention; [Figure 4] 4 is a flowchart illustrating a process executed in a vehicle control system according to an aspect of the present invention. [Figure 5] FIG. 10 is a diagram showing changes over time in pressing torque and braking force. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a diagram showing an example of a vehicle control system according to an embodiment of the present invention. The vehicle control system 1 is a system that controls a vehicle equipped with a motor, an engine, and a brake. Note that the vehicle controlled by the vehicle control system 1 does not necessarily have to be equipped with an engine.

[0011] The vehicle control system 1 includes a motor control device 10, a brake control device 20, and an engine control device 30. The motor control device 10 is a device that controls a motor mounted on a vehicle. The brake control device 20 is a device that controls a brake mounted on a vehicle. The engine control device 30 is a device that controls a motor mounted on a vehicle. Specific examples of the motor control device 10, the brake control device 20, and the engine control device 30 include an ECU (Electronic Control Unit). The motor control device 10, the brake control device 20, and the engine control device 30 can communicate data with each other via a network such as an in-vehicle LAN (Local Area Network).

[0012] 2 is a block diagram showing the configuration of a motor control device 10 according to one embodiment of the present invention. Motor control device 10 includes a calculation device 100, a communication interface (I / F) 110, and a storage device 120. Communication I / F 110 is an interface that transmits and receives signals between motor control device 10 and other devices installed in the vehicle.

[0013] The storage device 120 is a storage device that stores the vehicle control program executed by the arithmetic device 100 and various information processed by the arithmetic device 100 .

[0014] The arithmetic device 100 is an arithmetic device such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The arithmetic device 100 executes a vehicle control program 101 stored in a storage device 120, thereby performing a vehicle control method defined by the vehicle control program 101. The vehicle control program 101 includes a torque calculation unit 102, a braking force calculation unit 103, and a motor control unit 104. Note that an integrated circuit such as an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit) may execute the vehicle control program.

[0015] The torque calculation unit 102 is a program that calculates a torque (hereinafter referred to as "pushing torque") for eliminating backlash in the gears of the vehicle. As the pushing torque, a torque of a magnitude necessary and sufficient to eliminate backlash in the gears can be adopted.

[0016] The braking force calculation unit 103 is a program that calculates the brake braking force using the pushing torque calculated by the torque calculation unit 102. Specifically, the braking force calculation unit 103 calculates the required braking force by multiplying the pushing torque by a gain, which is a parameter. Target value The braking force calculation unit 103 calculates the upper limit of the braking force by multiplying the braking force by a predetermined rate. The predetermined rate is a value at which the braking force exceeds the pressing torque to ensure safety. The predetermined rate can be determined based on the variation in motor torque and the temperature characteristics of the magnet inside the motor. The braking force calculation unit 103 generates a command value for the braking force based on the calculated braking force and the upper limit of the braking force.

[0017] The motor control unit 104 is a program that controls the motor based on the pushing torque calculated by the torque calculation unit 102. The motor control unit 104 causes the motor to output the pushing torque and applies the torque to the propeller shaft, thereby preventing gear rattle noise.

[0018] 3 is a block diagram showing the configuration of a brake control device 20 according to one embodiment of the present invention. The brake control device 20 includes a calculation device 200, a communication I / F 210, and a storage device 220. The communication I / F 210 is an interface for transmitting and receiving signals between the brake control device 20 and other devices installed in the vehicle.

[0019] The storage device 220 is a storage device that stores the vehicle control program executed by the arithmetic device 200 and various information processed by the arithmetic device 200 .

[0020] The arithmetic device 200 is an arithmetic device such as a CPU or an MPU. The arithmetic device 200 executes a vehicle control program 201 stored in the storage device 220, thereby performing a vehicle control method defined by the vehicle control program 201. The vehicle control program 201 includes a brake control unit 202. Note that an integrated circuit such as an FPGA or an ASIC may execute the vehicle control program.

[0021] The brake control unit 202 is a program that controls the brakes provided in the vehicle. Specifically, the brake control unit 202 controls the brake wheel cylinders via the brake actuators based on the command value of the brake braking force generated by the braking force calculation unit 103. In other words, the brake control unit 202 controls the brakes based on the brake braking force whose upper limit is the braking force upper limit value.

[0022] Fig. 4 is a flowchart showing an example of processing executed by the vehicle control system 1. The processing shown in Fig. 4 is executed when a request to start the engine is made while the shift lever is set to the parking range.

[0023] In step S1, the motor control device 10 calculates a target value of the pushing torque. In step S2, the motor control device 10 calculates a target value of the pushing torque. toIn step S3, the motor control device 10 calculates the braking force upper limit by multiplying the target value of the pushing torque by a predetermined rate. In step S4, the motor control device 10 generates a command value for the braking force based on the calculated braking force and the braking force upper limit.

[0024] In step S5, the motor control device 10 notifies the brake control device 20 of the brake braking force command value. When the brake control device 20 is notified of the brake braking force command value from the motor control device 10, the brake control device 20 calculates the target value of the brake braking force in step S6. Here, when multiple brake braking force requests compete with each other, the brake braking force command value related to the brake braking force request with the highest priority is selected as the target value of the brake braking force.

[0025] In step S7, the brake control device 20 controls the brake wheel cylinders via the brake actuators based on the calculated target value of the braking force.

[0026] Next, in step S8, the motor control device 10 controls the motor based on the target value of the pushing torque, and the motor starts to output the pushing torque. Once the motor has completed outputting the pushing torque, in step S9, the engine control device 30 starts cranking the engine, thereby starting the engine.

[0027] Fig. 5 is a diagram showing changes over time in the pushing torque and the braking force, which are based on the present invention and the pushing torque and the braking force calculated based only on gain processing.

[0028] As shown in Figure 5, when calculating the brake braking force based only on gain processing, the gain must be reduced to achieve the same upper limit value of the braking force as the upper limit value of the present invention. As a result, the slope of the brake braking force becomes smaller, and the response time Tm until the upper limit value of the braking force is reached becomes longer, resulting in a decrease in brake responsiveness. In addition, the actual braking force, which corresponds to the difference between the brake braking force and the pushing torque, becomes smaller, which may cause the vehicle to move during pushing control.

[0029] On the other hand, in the present invention, the gain is not reduced, and the braking force calculation unit 103 of the motor control device 10 calculates the required braking force by multiplying the gain by the pushing torque, and calculates the braking force upper limit value by multiplying the pushing torque by a predetermined rate. Then, the brake control unit 202 of the brake control device 20 controls the brakes based on the braking force whose upper limit is the braking force upper limit value. As a result, compared to braking force based only on gain processing, the slope of the braking force is larger and the response time Tm is shorter, thereby improving brake responsiveness. Furthermore, compared to technology that employs braking force based only on gain processing, the actual braking force can be made larger, making it possible to prevent the vehicle from moving during pushing control.

[0030] In the above examples, the program includes instructions (or software code) that, when loaded into a computer, cause the computer to perform one or more functions described in the embodiments. The program may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable medium or tangible storage medium includes random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disk (DVD), Blu-ray® disk or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The program may also be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable medium or communication medium includes electrical, optical, acoustic, or other forms of propagated signals.

[0031] The present invention is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0032] 1. Vehicle control system 10 Motor control device 20 Brake control device 30 Engine control device 100 Computing equipment 101 Vehicle Control Program 102 Torque calculation unit 103 Braking force calculation section 104 Motor control unit 110 Communication I / F 120 Storage device 200 Computing equipment 201 Vehicle Control Program 202 Brake control unit 210 Communication I / F 220 Storage device

Claims

[Claim 1] A vehicle control system for controlling a vehicle equipped with a motor and a brake, a torque calculation unit that calculates a pushing torque that increases toward a fixed target value in order to eliminate backlash in a gear provided in the vehicle; a braking force calculation unit that calculates a braking force required for the brake; a motor control unit that controls the motor based on the pressing torque; a brake control unit that controls the brakes based on the braking force; Including, The braking force calculation unit calculating an upper limit value of the braking force by multiplying the target value of the pushing torque by a predetermined rate that is a value at which the braking force exceeds the target value of the pushing torque; multiplying the pressing torque by a gain that is greater than the predetermined rate to calculate a required braking force of the brake; generating a command value for the required braking force with the calculated upper limit value as an upper limit, and notifying the brake control unit of the command value; the brake control unit, when notified of a plurality of the command values, selects the command value relating to a brake braking force request with a high priority; controlling the brake based on the required braking force corresponding to the selected command value and the upper limit value, with the upper limit value being the upper limit; Vehicle control system.

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