Dual redundant single axis electro-hydraulic brake system and control method

Abstract

The present application relates to the technical field of braking system, in particular to a double-redundant single-axis electro-hydraulic braking system and control method. The double-redundant single-axis electro-hydraulic braking system is characterized in that: the brake fluid storage pot is a two-cavity brake fluid storage pot or a three-cavity brake fluid storage pot, the brake fluid storage pot comprises a first storage cavity, a second storage cavity and a third storage cavity, the first storage cavity is connected with a left brake control mechanism, the second storage cavity is connected with a right brake control mechanism, the left brake control mechanism and the right brake control mechanism are connected through a plurality of balance valves, and the plurality of balance valves are connected in parallel. Compared with the prior art, the redundancy mode of the brake control mechanism, the electromagnetic valve and the balance valve is increased, the working mode is not a single switching and starting mode, but a free and flexible replacement working mode according to the failure condition, which greatly increases the redundancy control condition of the braking system in response to various failure conditions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of braking system, in particular to a dual-redundant single-axle electro-hydraulic braking system and control method. BACKGROUND

[0002] The traditional central electro-hydraulic braking system architecture generally only has redundancy backup on electrical elements, and if composite function backup is required, an additional system needs to be added; the new distributed electro-mechanical braking system is almost unable to realize manual braking or the manual braking structure is very complex and inefficient under power failure.

[0003] The main purpose of the present application is to comply with the electronic and intelligent trend of automobiles, and to distinguish from the traditional central electro-hydraulic braking architecture based on solenoid valves to realize advanced braking functions, the present application provides a distributed braking architecture based on motors to directly realize advanced braking functions, which is applied in a distributed manner in units of single axle (bridge), and adapts to the future distributed application of electro-hydraulic and electro-mechanical braking systems between axles to form a reasonable distributed combination; the function redundancy backup in the same module is realized by the solenoid valves in the same module and the two sets of controllers independently powered, and the same braking effect as the traditional hydraulic braking system under power failure is also realized. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the present application provides a dual-redundant single-axle electro-hydraulic braking system and control method, which increases the redundancy mode of the braking control mechanism, solenoid valve and balance valve, and the working mode is not a single switching and starting mode, but a free and flexible replacement working mode according to failure conditions, which greatly increases the redundancy control conditions of the braking system in response to various failure conditions.

[0005] To achieve the above purpose, a dual-redundant single-axle electro-hydraulic braking system is designed, which comprises a brake fluid storage pot, characterized in that: the brake fluid storage pot is a two-cavity brake fluid storage pot or a three-cavity brake fluid storage pot, and the brake fluid storage pot comprises a first storage cavity, a second storage cavity and a third storage cavity; the first storage cavity is connected with a left brake control mechanism, and the second storage cavity is connected with a right brake control mechanism; a plurality of balance valves are connected between the left brake control mechanism and the right brake control mechanism in parallel.

[0006] The left brake control mechanism and the right brake control mechanism have the same structure, and the left brake control mechanism comprises a left electric brake actuator, a left pressure sensor and a left hydraulic brake; the first storage cavity is connected with a left solenoid valve, the left electric brake actuator and the left hydraulic brake through a circuit; and the left pressure sensor is connected to the connection circuit of the left electric brake actuator and the left hydraulic brake.

[0007] The brake fluid storage pot is connected in series with the left brake control mechanism and the right brake control mechanism through the manual brake mechanism, the manual brake mechanism includes a manual brake device, a stroke brake intention sensor, a brake master cylinder, a pressure brake intention sensor, an electromagnetic valve, a first storage cavity and a second storage cavity, the hydraulic output end of the first storage cavity and the second storage cavity is connected with the hydraulic input end of the brake master cylinder, the piston push rod of the brake master cylinder is connected with the manual brake device, the hydraulic output end of the brake master cylinder is connected with the input end of the left electromagnetic valve and the right electromagnetic valve respectively, the output end of the left electromagnetic valve is divided into two paths, one path is connected with the third storage cavity, and the other path is connected with the left brake control mechanism, the output end of the right electromagnetic valve is divided into two paths, one path is connected with the third storage cavity, and the other path is connected with the right brake control mechanism, the stroke brake intention sensor is connected on the line between the brake master cylinder and the manual brake device, and the pressure brake intention sensor is connected on the line between the brake master cylinder and the left electromagnetic valve.

[0008] The manual brake device is a lever brake device or a cable brake device.

[0009] The left electromagnetic valve and the left brake control mechanism are connected in series through a redundant left electromagnetic valve, and the right electromagnetic valve and the right brake control mechanism are connected in series through a redundant right electromagnetic valve.

[0010] A control method of a double-redundant single-shaft electro-hydraulic brake system, including a control method of any one of the left side and the right side failure, a control method of the left side and the right side simultaneous failure, and a control method of the balance valve failure.

[0011] The specific process of the control method of any one of the left side and the right side failure is as follows:

[0012] S11, it is judged whether the left brake control mechanism fails completely, if yes, step S12 is performed, otherwise, step S13 is performed;

[0013] S12, when the left brake control mechanism fails completely, the system directly starts the right brake control mechanism to perform the whole vehicle braking work;

[0014] S13, when the left brake control mechanism fails partially, step S14 is performed, otherwise, step S11 is returned;

[0015] S14, it is judged whether the left electromagnetic valve fails, if yes, step S18 is performed, otherwise, step S15 is performed;

[0016] S15, it is judged whether the left pressure sensor fails, if yes, step S19 is performed, otherwise, step S16 is performed;

[0017] S16, it is judged whether the left electric brake actuator fails, if yes, step S20 is performed, otherwise, step S17 is performed;

[0018] S17, determining whether the left hydraulic brake fails, if yes, going to step S21; otherwise, returning to step S13;

[0019] S18, when the left electromagnetic valve fails, the right electromagnetic valve of the right brake control mechanism substitutes the left electromagnetic valve to continue working;

[0020] S19, when the left pressure sensor fails, using a backup algorithm to control the braking force, and calibrating and assisting the control of the backup algorithm through the balance valve and the right pressure sensor of the right brake control mechanism;

[0021] S20, when the left electric brake actuator fails, the right electric brake actuator of the right brake control mechanism substitutes the left electric brake actuator to continue working;

[0022] S21, when the left hydraulic brake fails, the left pressure sensor displays failure data; going to step S19.

[0023] In the step S18, when the control circuit of the left electromagnetic valve fails, the right electromagnetic valve of the right brake control mechanism substitutes the left electromagnetic valve to continue working; when the left electromagnetic valve mechanically fails, the left brake control mechanism is braked by the manual brake device, and the right brake control mechanism is braked by the right electric brake actuator and the right hydraulic brake.

[0024] The specific process of the control method when the left and right brake control mechanisms fail simultaneously is as follows:

[0025] S21, when the left and right brake control mechanisms fail simultaneously, the manual brake device directly brakes.

[0026] The specific process of the control method when the balance valve fails is as follows:

[0027] S31, when the balance valve fails, determining whether there is a redundant balance valve, if yes, going to step S32; otherwise, going to step S33;

[0028] S32, when there is a redundant balance valve connected in parallel with the balance valve, when the balance valve fails, the redundant balance valve is started to substitute the balance valve to continue working;

[0029] S33, when there is no redundant balance valve, the left brake control mechanism and the right brake control mechanism are controlled respectively, and an alarm is sent to prompt to repair as soon as possible.

[0030] Compared with the prior art, the application provides a redundancy control system and method based on a single-axis electro-hydraulic review braking system, redundancy modes of a braking control mechanism, an electromagnetic valve and a balance valve are added, and the working mode is not a single switching and starting mode, but a free and flexible replacement working mode according to failure conditions, so that the redundancy control conditions of the braking system are greatly increased in response to various failure conditions. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a connection schematic diagram of the application scheme one.

[0032] Figure 2 It is a connection schematic diagram of the application scheme two.

[0033] Figure 3 It is a connection schematic diagram of the application scheme three.

[0034] Figure 4 It is a connection schematic diagram of the application scheme four.

[0035] Figure 5 It is a connection schematic diagram of information interaction between sensors.

[0036] Figure 6 It is an interaction connection schematic diagram of the electromagnetic valve, the balance valve and the electric brake actuator.

[0037] Figure 7 It is a schematic diagram of the principle of the normal two-side independent electro-hydraulic braking triggered by manpower.

[0038] Figure 8 It is a schematic diagram of the principle of the electro-hydraulic braking under the condition of one-side failure.

[0039] Figure 9 It is a schematic diagram of the principle of the manpower braking under the condition of two-side failure. DETAILED DESCRIPTION

[0040] The application will be further described below according to the drawings.

[0041] As shown in the figure, it is a redundancy system in a pure line control mode without personnel intervention, and the brake fluid storage pot 1 is a two-cavity brake fluid storage pot. Figure 4 The brake fluid storage pot 1 includes a first storage cavity T1 and a second storage cavity T2. The first storage cavity T1 is connected with a left brake control mechanism, and the second storage cavity T2 is connected with a right brake control mechanism. The left brake control mechanism and the right brake control mechanism are connected through a plurality of balance valves EMV3, and the plurality of balance valves EMV3 are connected in parallel.

[0042] The left brake control mechanism is consistent with the right brake control mechanism, the left brake control mechanism comprises a left electric brake actuator, a left pressure sensor and a left hydraulic brake, the first liquid storage cavity T1 is connected with the left electromagnetic valve EMV1, the left electric brake actuator 2 and the left hydraulic brake 4 through a line, and the left pressure sensor 3 is connected to the connecting line between the left electric brake actuator 2 and the left hydraulic brake 4.

[0043] As shown in Figure 1 , Figure 2 , on the basis of the pure drive-by-wire mode, a redundant system of the manual brake mode is added, the manual brake mechanism is connected in series between the brake liquid storage pot 1 and the left brake control mechanism and the right brake control mechanism, the manual brake mechanism comprises a manual brake device, a stroke type brake intention sensor, a brake master cylinder, a pressure type brake intention sensor and an electromagnetic valve, the hydraulic output ends of the first liquid storage cavity T1 and the second liquid storage cavity T3 are connected with the hydraulic input end of the brake master cylinder 7, the piston push rod of the brake master cylinder 7 is connected with the manual brake device 6, the hydraulic output end of the brake master cylinder 7 is connected with the input ends of the left electromagnetic valve EMV1 and the right electromagnetic valve EMV2 respectively, the output end of the left electromagnetic valve EMV1 is connected with the third liquid storage cavity T0 and the left brake control mechanism in two ways, the output end of the right electromagnetic valve EMV2 is connected with the third liquid storage cavity T0 and the right brake control mechanism in two ways, the stroke type brake intention sensor 5 is connected to the line between the brake master cylinder 7 and the manual brake device 6, and the pressure type brake intention sensor 8 is connected to the line between the brake master cylinder 7 and the left electromagnetic valve EMV1.

[0044] The manual brake device is a lever type brake device or a cable type brake device.

[0045] As shown in Figure 7 , when the manual brake mechanism works, the brake master cylinder 7 works, the left electromagnetic valve EMV1 and the right electromagnetic valve EMV2 are electrified at the same time, so that the left brake control mechanism and the right brake control mechanism work normally at the same time.

[0046] As shown in Figure 3 , on the basis of Figure 2 , the left electromagnetic valve EMV1 and the right electromagnetic valve EMV2 are connected in series with the redundant left electromagnetic valve EMV1' and the redundant right electromagnetic valve EMV2' between the left brake control mechanism and the right brake control mechanism.

[0047] As shown in Figure 5 , Figure 6As shown, a control method of a dual-redundant single-axis electro-hydraulic braking system, the redundancy control method includes a control method for failure of either the left or right side, a control method for simultaneous failure of the left and right sides, and a control method for failure of the balance valve EMV3.

[0048] The specific process of the control method for failure of either the left or right side is as follows:

[0049] S11, determine whether the left brake control mechanism has failed completely, if yes, proceed to step S12; otherwise, proceed to step S13;

[0050] S12, when the left brake control mechanism has failed completely, the system directly activates the right brake control mechanism to perform vehicle braking;

[0051] S13, when the left brake control mechanism has failed partially, proceed to step S14; otherwise, return to step S11;

[0052] S14, determine whether the left electromagnetic valve EMV1 has failed, if yes, proceed to step S18; otherwise, proceed to step S15;

[0053] S15, determine whether the left pressure sensor 3 has failed, if yes, proceed to step S19; otherwise, proceed to step S16;

[0054] S16, determine whether the left electric brake actuator 2 has failed, if yes, proceed to step S20; otherwise, proceed to step S17;

[0055] S17, determine whether the left hydraulic brake 4 has failed, if yes, proceed to step S21; otherwise, return to step S13;

[0056] S18, when the left electromagnetic valve EMV1 has failed, the right electromagnetic valve EMV2 of the right brake control mechanism replaces the left electromagnetic valve EMV1 to continue working;

[0057] S19, when the left pressure sensor 3 has failed, use a backup algorithm for brake force control, and use the balance valve EMV3 and the right pressure sensor of the right brake control mechanism for backup algorithm calibration and auxiliary control;

[0058] S20, when the left electric brake actuator 2 has failed, the right electric brake actuator of the right brake control mechanism replaces the left electric brake actuator 2 to continue working;

[0059] S21, when the left hydraulic brake 4 has failed, the left pressure sensor 3 will display failure data; proceed to step S19.

[0060] When the control circuit of the left electromagnetic valve EMV1 fails in step S18, the right electromagnetic valve EMV2 of the right brake control mechanism replaces the left electromagnetic valve EMV1 to continue working, as shown in Figure 8 When the left electromagnetic valve EMV1 fails mechanically, the left brake control mechanism is braked by the manual brake device 6, and the right brake control mechanism is braked by the right electric brake actuator and the right hydraulic brake.

[0061] As shown in Figure 9 When both the left and right sides fail simultaneously, the specific process of the control method of the system is as follows:

[0062] S21, when the left and right brake control mechanisms fail simultaneously, the manual brake device 6 directly brakes.

[0063] The specific process of the control method when the balance valve EMV3 fails is as follows:

[0064] S31, when the balance valve EMV3 fails, it is determined whether there is a redundant balance valve, if yes, step S32 is performed; otherwise, step S33 is performed.

[0065] S32, when there is a redundant balance valve in parallel with the balance valve EMV3, when the balance valve EMV3 fails, the redundant balance valve is started to replace the balance valve EMV3 to continue working;

[0066] S33, when there is no redundant balance valve, the left brake control mechanism and the right brake control mechanism are controlled respectively, and an alarm is issued to prompt to repair as soon as possible.

[0067] The application scenario of the application is a single-shaft electro-hydraulic composite brake system, which has a double brake redundancy performance. When one side of the electric control or brake fails, the electric control and the execution system of the other side can control the other side. When the power is completely cut off, manual or other mechanical force can be used for backup braking.

[0068] The application targets single-shaft braking needs, controls the left side of the shaft independently, and has a mutual backup redundancy safety braking architecture. The electric brake actuator has an ABS function and can independently adjust the side braking force. The wheel edge hydraulic brake actuator is low-cost and reliable. It has a distributed arrangement and is suitable for multi-shaft special vehicles. It is particularly suitable for new energy electric vehicles and the combination of wheel edge mechanical braking and hydraulic braking between different shafts.

Claims

1. A control method of a dual redundant single shaft electro-hydraulic brake system, characterized by: The system comprises a brake fluid storage tank (1), the brake fluid storage tank (1) is a three-cavity brake fluid storage tank, the brake fluid storage tank (1) comprises a first storage cavity (T1), a second storage cavity (T2) and a third storage cavity (T0), the first storage cavity (T1) is connected with a left brake control mechanism, the second storage cavity (T2) is connected with a right brake control mechanism, the left brake control mechanism and the right brake control mechanism are connected through a plurality of balance valves (EMV3), and the plurality of balance valves (EMV3) are connected in parallel; The left brake control mechanism and the right brake control mechanism are identical in structure, the left brake control mechanism comprises a left electric brake actuator, a left pressure sensor and a left hydraulic brake, the first storage cavity (T1) is connected with a left electromagnetic valve (EMV1), the left electric brake actuator (2) and the left hydraulic brake (4) through lines, and the left pressure sensor (3) is connected to the connection line between the left electric brake actuator (2) and the left hydraulic brake (4); The control method comprises a control method for failure of any one of the left side and the right side, a control method for simultaneous failure of the left side and the right side and a control method for failure of the balance valve (EMV3); The specific process of the control method for failure of any one of the left side and the right side is as follows: S11, determining whether the left brake control mechanism fails completely, if yes, proceeding to step S12; otherwise, proceeding to step S13; S12, when the left brake control mechanism fails completely, the system directly starts the right brake control mechanism to perform vehicle braking work; S13, when the left brake control mechanism fails partially, if yes, proceeding to step S14; otherwise, returning to step S11; S14, determining whether the left electromagnetic valve (EMV1) fails, if yes, proceeding to step S18; otherwise, proceeding to step S15; S15, determining whether the left pressure sensor (3) fails, if yes, proceeding to step S19; otherwise, proceeding to step S16; S16, determining whether the left electric brake actuator (2) fails, if yes, proceeding to step S20; otherwise, proceeding to step S17; S17, determining whether the left hydraulic brake (4) fails, if yes, proceeding to step S21; otherwise, returning to step S13; S18, when the left electromagnetic valve (EMV1) fails, the right electromagnetic valve (EMV2) of the right brake control mechanism replaces the left electromagnetic valve (EMV1) to continue working; S19, when the left pressure sensor (3) fails, a backup algorithm is used to control braking force, and the backup algorithm is calibrated and assisted by the right pressure sensor of the right brake control mechanism through the balance valve (EMV3); S20, when the left electric brake actuator (2) fails, the right electric brake actuator of the right brake control mechanism replaces the left electric brake actuator (2) to continue working; S21, when the left hydraulic brake (4) fails, the left pressure sensor (3) displays failure data; proceeding to step S19; ​ The control method for simultaneous failure of the left and right sides is that when the left and right brake control mechanisms simultaneously fail, the manual brake device (6) directly brakes; The specific process of the control method for failure of the balance valve (EMV3) is as follows: S31, when the balance valve (EMV3) fails, it is determined whether there is a redundant balance valve, if yes, step S32 is performed; otherwise, step S33 is performed; S32, when there is a redundant balance valve in parallel with the balance valve (EMV3), when the balance valve (EMV3) fails, the redundant balance valve is started to replace the balance valve (EMV3) to continue to work; S33, when there is no redundant balance valve, the left brake control mechanism and the right brake control mechanism are controlled respectively, and an alarm is issued to prompt to repair as soon as possible.

2. The control method of a dual redundant single shaft electro-hydraulic brake system according to claim 1, characterized in that: The manual brake mechanism is connected in series between the brake liquid storage pot (1) and the left brake control mechanism and the right brake control mechanism, and the manual brake mechanism includes a manual brake device, a travel type brake intention sensor, a brake master cylinder, a pressure type brake intention sensor, a solenoid valve, a first storage cavity (T1) and a second storage cavity (T3) hydraulic output end connected to the hydraulic input end of the brake master cylinder (7), the piston push rod of the brake master cylinder (7) is connected to the manual brake device (6), the hydraulic output end of the brake master cylinder (7) is respectively connected to the input end of the left solenoid valve (EMV1) and the right solenoid valve (EMV2), the output end of the left solenoid valve (EMV1) is connected to the third storage cavity (T0) in one way and connected to the left brake control mechanism in another way, the output end of the right solenoid valve (EMV2) is connected to the third storage cavity (T0) in one way and connected to the right brake control mechanism in another way, the travel type brake intention sensor (5) is connected between the brake master cylinder (7) and the manual brake device (6), and the pressure type brake intention sensor (8) is connected between the brake master cylinder (7) and the left solenoid valve (EMV1).

3. The control method of a dual redundant single shaft electro-hydraulic brake system according to claim 2, characterized in that: The manual brake device (6) is a lever type brake device or a cable type brake device.

4. The control method of a dual redundant single shaft electro-hydraulic brake system according to claim 2, characterized in that: The left solenoid valve (EMV1) and the left brake control mechanism are connected in series with a redundant left solenoid valve (EMV1'), and the right solenoid valve (EMV2) and the right brake control mechanism are connected in series with a redundant right solenoid valve (EMV2').

5. The control method of a dual redundant single shaft electro-hydraulic brake system according to claim 1, characterized in that: In step S18, when the control circuit of the left solenoid valve (EMV1) fails, the right solenoid valve (EMV2) of the right brake control mechanism replaces the left solenoid valve (EMV1) to continue to work; when the left solenoid valve (EMV1) mechanically fails, the left brake control mechanism is braked by the manual brake device (6), and the right brake control mechanism is jointly braked by the right electric brake actuator and the right hydraulic brake.

Images