阅读说明：本技术 一种辅助线控制动的能量回收系统及其控制方法 (Energy recovery system assisting brake-by-wire and control method thereof ) 是由 储雨凯 周小川 赵万忠 栾众楷 章波 吴金卫 王睿 于 2021-08-17 设计创作，主要内容包括：本发明公开了一种辅助线控制动的能量回收系统及其控制方法,包括：油门踏板、油门踏板压力传感器、车速传感器、制动踏板、制动踏板压力传感器、电子液压制动系统总成、柱塞泵离合装置、柱塞泵高压回路总成及主控制器；本发明具备节约能源的功能,能在汽车制动时利用自车动能通过地面摩檫力带动汽车车轮旋转,再通过汽车传动系统带动变速器输出轴旋转,再通过柱塞泵离合装置带动柱塞泵工作,以此来补充蓄能器的能量,能大大减少汽车在长下坡制动或减速制动时消耗的能量。(The invention discloses an energy recovery system assisting brake-by-wire and a control method thereof, wherein the energy recovery system comprises: the system comprises an accelerator pedal, an accelerator pedal pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor, an electronic hydraulic brake system assembly, a plunger pump clutch device, a plunger pump high-pressure loop assembly and a main controller; the energy-saving brake device has the function of saving energy, can drive the wheels of the automobile to rotate by utilizing the kinetic energy of the automobile through the ground friction force when the automobile is braked, then drives the output shaft of the speed changer to rotate through the automobile transmission system, and then drives the plunger pump to work through the plunger pump clutch device, so as to supplement the energy of the energy accumulator, and can greatly reduce the energy consumed when the automobile is braked on a long downhill or decelerated.)

1. An energy recovery system to assist brake-by-wire, comprising: the system comprises an accelerator pedal, an accelerator pedal pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor, an electronic hydraulic brake system assembly, a plunger pump clutch device, a plunger pump high-pressure loop assembly and a main controller; wherein the content of the first and second substances,

the accelerator pedal is connected with an accelerator pedal pressure sensor;

the accelerator pedal pressure sensor is connected with the main controller;

the vehicle speed sensor is connected with the main controller;

the brake pedal is connected with a brake pedal pressure sensor;

the brake pedal pressure sensor is connected with the main controller;

the electro-hydraulic brake system assembly includes: the device comprises an oil storage tank, a motor pump, a first one-way check valve, a third one-way check valve, an energy accumulator pressure sensor, an overflow valve, a pressure increasing valve, a pressure reducing valve, a wheel cylinder pressure sensor, a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve and a fifth three-way valve; the overflow valve, the pressure increasing valve, the pressure reducing valve and the motor pump are all connected with and controlled by the main controller; the energy accumulator pressure sensor and the wheel cylinder pressure sensor are both connected with the main controller; the oil storage tank is connected with an oil inlet of the first three-way valve through an oil pipe, a first oil outlet of the first three-way valve is connected with the motor pump through the oil pipe, and a second oil outlet of the first three-way valve is closed; a first one-way check valve is arranged on an oil pipe between the first three-way valve and the motor pump, so that hydraulic oil flows to the motor pump from the first three-way valve; the motor pump is connected with a first oil inlet of the second three-way valve through an oil pipe, a second oil inlet of the second three-way valve is closed, a third one-way check valve is installed between the motor pump and the second three-way valve, hydraulic oil flows to the second three-way valve from the motor pump, an oil outlet of the second three-way valve is connected with an energy accumulator through an oil pipe, the energy accumulator is connected with an oil inlet of the third three-way valve through an oil pipe, an energy accumulator pressure sensor is installed in the oil pipe between the third three-way valve and the energy accumulator, a first oil outlet of the third three-way valve is connected with an overflow valve through an oil pipe, the overflow valve is connected with a first oil inlet of the fifth three-way valve through an oil pipe, a second oil outlet of the third three-way valve is connected with a pressure increasing valve through an oil pipe, the pressure increasing valve is connected with an oil inlet of the fourth three-way valve through an oil pipe, a first oil outlet of the fourth three-way valve is connected with a pressure reducing valve through an oil pipe, and a second oil outlet of the fourth three-way valve is connected with a wheel cylinder through an oil pipe, a wheel cylinder pressure sensor is arranged in an oil pipe between the fourth three-way valve and the wheel cylinder, the pressure reducing valve is connected with a second oil inlet of the fifth three-way valve through the oil pipe, and an oil outlet of the fifth three-way valve is connected with the oil storage tank through the oil pipe;

the plunger pump clutch device comprises: the clutch device comprises a transmission output shaft spline hub, a transmission output shaft driving gear combined gear ring, a synchronizer, a transmission output shaft driven gear, a combined sleeve and a clutch solenoid valve; the combination sleeve and the transmission output shaft spline hub synchronously rotate and slide on the transmission output shaft spline hub along the axial direction of the transmission output shaft, the transmission output shaft driving gear is closely attached to and synchronously rotates with the transmission output shaft driving gear in combination with the gear ring, the synchronizer is arranged between the transmission output shaft driving gear in combination with the gear ring and the transmission output shaft spline hub, and the transmission output shaft driving gear is meshed with the transmission output shaft driven gear; the clutch electromagnetic valve is connected with the outer ring of the combination sleeve;

plunger pump high pressure return circuit assembly includes: the plunger pump, the second one-way check valve and the fourth one-way check valve; a low-pressure inlet of the plunger pump is connected with a second oil outlet of the first three-way valve through an oil pipe, and a high-pressure outlet of the plunger pump is connected with a second oil inlet of the second three-way valve through an oil pipe; the second one-way check valve is arranged between the first three-way valve and the plunger pump and is used for enabling hydraulic oil to flow to the plunger pump from the first three-way valve; the fourth one-way check valve is arranged between the plunger pump and the second three-way valve and used for enabling hydraulic oil to flow from the plunger pump to the second three-way valve; the rotor of the plunger pump is coaxially connected with a driven gear of an output shaft of the transmission;

the main controller is connected with an overflow valve, a pressure increasing valve, a pressure reducing valve, a motor pump, an energy accumulator pressure sensor, a wheel cylinder pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor and an accelerator pedal pressure sensor through connecting wires; the main controller receives signals of the motor pump, the energy accumulator pressure sensor, the wheel cylinder pressure sensor, the vehicle speed sensor, the brake pedal pressure sensor and the accelerator pedal pressure sensor, and controls the opening and closing states of the overflow valve, the pressure increasing valve and the pressure reducing valve and the rotating speed of the motor pump.

2. The brake-by-wire assisted energy recovery system of claim 1, wherein the first three-way valve is a one-in-two-out valve; the second three-way valve is a valve with two inlets and one outlet; the third three-way valve is a valve with one inlet and two outlets; the fifth three-way valve is a valve with two inlets and one outlet; the fourth three-way valve is a valve with one inlet and two outlets.

3. The energy recovery system for assisting brake-by-wire according to claim 1, wherein the vehicle speed sensor is used for collecting vehicle speed information and transmitting the vehicle speed information to the main controller, when the vehicle speed is zero, the main controller controls the plunger pump clutch device to realize a combined state, and only when the accelerator pedal pressure sensor transmits a signal that the accelerator pedal is stepped on to the main controller, the main controller controls the plunger pump clutch device to realize a separated state; when the vehicle speed is not zero, the main controller receives a brake pedal treaded signal sent by the brake pedal pressure sensor, controls the plunger pump clutch device to realize a combination state, receives a brake pedal released signal sent by the brake pedal pressure sensor, and controls the plunger pump clutch device to realize a separation state; when the pressure of the brake pedal is greater than zero, the brake pedal is stepped, and when the pressure of the brake pedal is equal to zero, the brake pedal is released; the pressure of the accelerator pedal is greater than zero, namely the accelerator pedal is pressed, and the pressure of the accelerator pedal is equal to zero, namely the accelerator pedal is released.

4. The brake-by-wire energy recovery system of claim 1, wherein the accumulator pressure sensor is configured to monitor a pressure in the accumulator, wherein there are an upper limit and a lower limit, the upper limit being controlled by the relief valve and the lower limit being controlled by the plunger pump and the motor pump.

5. The energy recovery system by-wire brake-assist according to claim 1, wherein the wheel cylinder pressure sensor is configured to monitor a pressure in a wheel cylinder, the pressure being controlled by a pressure increase valve and a pressure decrease valve; the magnitude of the braking force is controlled by controlling the pressure in the wheel cylinder to adjust the wheel slip ratio to maximize the adhesion coefficient of the wheel.

6. The energy recovery system of claim 1, wherein the plunger pump clutch device controls the connection between the coupling sleeve and the transmission output shaft driving gear coupling ring gear through the clutch solenoid valve, so that the transmission output shaft driving gear and the transmission output shaft spline hub synchronously rotate to drive the transmission output shaft driving gear to rotate, the synchronizer is located between the transmission output shaft spline hub and the transmission output shaft driving gear coupling ring gear to ensure the coupling between the transmission output shaft spline hub and the transmission output shaft driving gear coupling ring gear, and the transmission output shaft driving gear drives the transmission output shaft driven gear to rotate so as to drive the plunger pump to operate.

7. The brake-by-wire assisted energy recovery system of claim 1, wherein the plunger pump is a swash plate axial plunger pump comprising: the oil distribution disc comprises a return spring, a swash plate guide cover electromagnetic valve, a swash plate, a plunger cylinder body, an oil distribution disc and a plunger pump rotor; the oil distribution disc is characterized in that the return spring is positioned on one side, without the swash plate, of the swash plate guide cover and is connected with the swash plate guide cover, the electromagnetic valve of the swash plate guide cover is connected with the swash plate guide cover on one side with the swash plate, the swash plate guide cover is sleeved on a plunger pump rotor in an empty mode, the swash plate is tightly attached to the swash plate guide cover and is sleeved on the plunger pump rotor in an empty mode, six plungers uniformly distributed on the circumference of the swash plate are respectively connected with the plunger cylinder body, the plunger cylinder body is connected with the plunger pump rotor through splines and rotates synchronously, and the oil distribution disc tightly attached to the plunger cylinder body is sleeved on the plunger pump rotor in an empty mode.

8. A control method of an energy recovery system for assisting brake-by-wire based on the system of any one of claims 1 to 7, characterized by comprising the steps of:

1) the main controller respectively receives information collected by a vehicle speed sensor, an accelerator pedal pressure sensor and a brake pedal sensor, and controls the working state of the plunger pump clutch device according to the received information;

2) the main controller receives pressure information acquired by the pressure sensor of the energy accumulator, when the pressure value exceeds an upper threshold value, the main controller controls the overflow valve to be opened, the motor pump does not work, so that part of high-pressure oil directly returns to the oil storage tank without flowing through the wheel cylinder, and the upper threshold value is the limit pressure which can be born by the energy accumulator; when the pressure value is smaller than the lower threshold, the main controller controls the overflow valve to close, the motor pump works to pressurize the energy accumulator, the lower threshold is the lowest required pressure in the energy accumulator, and when the pressure value is between the upper threshold and the lower threshold, the main controller controls the overflow valve to close, and the motor pump does not work;

3) when the brake pedal is stepped on, the main controller calculates the required theoretical wheel cylinder pressure according to the brake pedal pressure, receives pressure information collected by the wheel cylinder pressure sensor and judges the pressure information, and when the pressure in the wheel cylinder is smaller than the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to be opened, the pressure reducing valve to be closed and supplements the pressure in the wheel cylinder; when the pressure in the wheel cylinder is equal to the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to close, the pressure reducing valve to close, and at the moment, the pressure in the wheel cylinder is the ideal pressure; when the pressure in the wheel cylinder is larger than the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to be closed, the pressure reducing valve to be opened and the pressure in the wheel cylinder to be released, so that the wheel cylinder pressure is controlled to be kept near the calculated theoretical wheel cylinder pressure.

9. The control method of the energy recovery system by wire-controlled braking according to claim 8, wherein the step 1) of controlling the working state of the plunger pump clutch device by the main controller specifically comprises the following steps:

11) the main controller receives a vehicle ignition signal, when the vehicle is in a flameout state, the main controller controls a clutch electromagnetic valve of the plunger pump clutch device to enable the combination sleeve to be combined with a transmission output shaft driving gear combination gear ring for a long time, the pressure reducing valve is always kept in a closed state, and the pressure increasing valve is always kept in an open state;

12) when the vehicle is in an ignition state and the vehicle speed is zero, the main controller controls a clutch solenoid valve of the plunger pump clutch device to enable the combination sleeve to be combined with the transmission output shaft driving gear combination gear ring, the pressure reducing valve is closed, and the pressure increasing valve is opened, so that the plunger pump is controlled to work;

13) when the vehicle is in an ignition state, the main controller receives a signal that the accelerator pedal is stepped on and sent by the accelerator pedal sensor, and controls a clutch electromagnetic valve of the plunger pump clutch device to enable the coupling sleeve to be separated from a transmission output shaft driving gear coupling gear ring, so that the plunger pump is controlled to stop working;

14) when the vehicle is in an ignition state, and the vehicle speed is zero and the accelerator pedal is stepped on, the main controller controls a clutch electromagnetic valve of the plunger pump clutch device to separate a combination sleeve from a transmission output shaft driving gear combination gear ring, so as to control the plunger pump to stop working;

15) when the vehicle is in an ignition state and the vehicle speed is not zero, the main controller receives a signal of the brake pedal sensor to control the working state of the plunger pump clutch device.

10. The method of claim 8, wherein the electronic hydraulic brake system assembly and the plunger pump high pressure circuit assembly are divided into two parts according to whether the oil path is directly connected to the oil reservoir, one part is a low pressure oil path directly connected to the oil reservoir, the hydraulic oil in the low pressure oil path is low pressure oil, the other parts are high pressure oil paths, and the hydraulic oil in the high pressure oil path is high pressure oil.

Technical Field

The invention belongs to the technical field of automobile brake systems, and particularly relates to an energy recovery system assisting brake-by-wire and a control method thereof.

Background

Under the influence of petroleum crisis and frequent occurrence of traffic accidents, people pay more and more attention to fuel economy and driving safety of automobiles, and a braking system is of great importance to driving safety and energy consumption of automobiles; the existing household automobile brake system is only a service brake system and a parking brake system, and the service brake system is usually arranged by adopting a cross pipeline, so that the running safety of an automobile is improved; the auxiliary braking system is generally used on heavy vehicles, and the energy recovery system is generally used on new energy vehicles.

In the prior auxiliary braking technology, the chinese patent application No. CN201520509777.0 discloses an exhaust braking system, which reuses the redundant high-pressure gas exhausted from an exhaust pipe through a pressure relief gas control device, i.e. the original redundant compressed air to be exhausted, which is generated in the exhaust braking process, is returned to an intake pipe through a series of control elements, thereby enhancing the intake of the intake pipe, improving the efficiency of exhaust braking, and shortening the time of exhaust braking. However, the above-mentioned technology needs to stop the fuel injection pump and close the exhaust pipe during braking, and this state cannot be maintained for a long time or may cause great damage to the engine.

In the existing braking energy recovery system, a dragging motor is adopted to reversely rotate so that the speed of the vehicle is reduced and the power is generated. For example: the Chinese invention patent application No. CN201710508913.8 discloses a series braking energy recovery system and a method; the series braking energy recovery system and the method provided by the patent enable the electric braking force and the hydraulic braking force to be generated firstly, on one hand, at most of time, due to the provision of the electric braking force, the loading frequency of the hydraulic braking force is reduced, and the integral energy recovery rate is improved; on the other hand, when the hydraulic braking force is generated, a superposition process is adopted, so that the discomfort of a user caused by the over-speed loading of the braking force is avoided, and the driving experience is improved; however, the above-described technology has a low efficiency of converting the kinetic energy of the vehicle into electric energy, a low efficiency of utilizing the kinetic energy possessed by the vehicle itself, and cannot effectively suppress the increase in the vehicle speed when the vehicle runs down a slope.

Disclosure of Invention

In view of the above-mentioned deficiencies of the prior art, the present invention aims to provide an energy recovery system for assisting brake-by-wire and a control method thereof, so as to solve the problems that the utilization efficiency of the vehicle's own kinetic energy is low, the energy consumption is high during the vehicle driving braking, the auxiliary braking system cannot continuously work during a long downhill, the vehicle speed of sliding down a slope is increased too fast, and the like, which are difficult to realize in the prior art.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

the invention relates to an energy recovery system for assisting brake-by-wire, which comprises: the system comprises an accelerator pedal, an accelerator pedal pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor, an electronic hydraulic brake system assembly, a plunger pump clutch device, a plunger pump high-pressure loop assembly and a main controller; wherein the content of the first and second substances,

the accelerator pedal is connected with an accelerator pedal pressure sensor;

the accelerator pedal pressure sensor is connected with the main controller;

the vehicle speed sensor is connected with the main controller;

the brake pedal is connected with a brake pedal pressure sensor;

the brake pedal pressure sensor is connected with the main controller;

the electro-hydraulic brake system assembly includes: the device comprises an oil storage tank, a motor pump, a first one-way check valve, a third one-way check valve, an energy accumulator pressure sensor, an overflow valve, a pressure increasing valve, a pressure reducing valve, a wheel cylinder pressure sensor, a first three-way valve, a second three-way valve, a third three-way valve, a fourth three-way valve and a fifth three-way valve; the overflow valve, the pressure increasing valve, the pressure reducing valve and the motor pump are all connected with and controlled by the main controller; the energy accumulator pressure sensor and the wheel cylinder pressure sensor are both connected with the main controller; the oil storage tank is connected with an oil inlet of the first three-way valve through an oil pipe, a first oil outlet of the first three-way valve is connected with the motor pump through the oil pipe, and a second oil outlet of the first three-way valve is closed; a first one-way check valve is arranged on an oil pipe between the first three-way valve and the motor pump, so that hydraulic oil flows to the motor pump from the first three-way valve; the motor pump is connected with a first oil inlet of the second three-way valve through an oil pipe, a second oil inlet of the second three-way valve is closed, a third one-way check valve is installed between the motor pump and the second three-way valve, hydraulic oil flows to the second three-way valve from the motor pump, an oil outlet of the second three-way valve is connected with an energy accumulator through an oil pipe, the energy accumulator is connected with an oil inlet of the third three-way valve through an oil pipe, an energy accumulator pressure sensor is installed in the oil pipe between the third three-way valve and the energy accumulator, a first oil outlet of the third three-way valve is connected with an overflow valve through an oil pipe, the overflow valve is connected with a first oil inlet of the fifth three-way valve through an oil pipe, a second oil outlet of the third three-way valve is connected with a pressure increasing valve through an oil pipe, the pressure increasing valve is connected with an oil inlet of the fourth three-way valve through an oil pipe, a first oil outlet of the fourth three-way valve is connected with a pressure reducing valve through an oil pipe, and a second oil outlet of the fourth three-way valve is connected with a wheel cylinder through an oil pipe, a wheel cylinder pressure sensor is arranged in an oil pipe between the fourth three-way valve and the wheel cylinder, the pressure reducing valve is connected with a second oil inlet of the fifth three-way valve through the oil pipe, and an oil outlet of the fifth three-way valve is connected with the oil storage tank through the oil pipe;

the plunger pump clutch device comprises: the clutch device comprises a transmission output shaft spline hub, a transmission output shaft driving gear combined gear ring, a synchronizer, a transmission output shaft driven gear, a combined sleeve and a clutch solenoid valve; the combination sleeve and the transmission output shaft spline hub synchronously rotate and slide on the transmission output shaft spline hub along the axial direction of the transmission output shaft, the transmission output shaft driving gear is closely attached to and synchronously rotates with the transmission output shaft driving gear in combination with the gear ring, the synchronizer is arranged between the transmission output shaft driving gear in combination with the gear ring and the transmission output shaft spline hub, and the transmission output shaft driving gear is meshed with the transmission output shaft driven gear; the clutch electromagnetic valve is connected with the outer ring of the combination sleeve;

plunger pump high pressure return circuit assembly includes: the plunger pump, the second one-way check valve and the fourth one-way check valve; a low-pressure inlet of the plunger pump is connected with a second oil outlet of the first three-way valve through an oil pipe, and a high-pressure outlet of the plunger pump is connected with a second oil inlet of the second three-way valve through an oil pipe; the second one-way check valve is arranged between the first three-way valve and the plunger pump and is used for enabling hydraulic oil to flow to the plunger pump from the first three-way valve; the fourth one-way check valve is arranged between the plunger pump and the second three-way valve and used for enabling hydraulic oil to flow from the plunger pump to the second three-way valve; the rotor of the plunger pump is coaxially connected with a driven gear of an output shaft of the transmission;

the main controller is connected with an overflow valve, a pressure increasing valve, a pressure reducing valve, a motor pump, an energy accumulator pressure sensor, a wheel cylinder pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor and an accelerator pedal pressure sensor through connecting wires; the main controller receives signals of the motor pump, the energy accumulator pressure sensor, the wheel cylinder pressure sensor, the vehicle speed sensor, the brake pedal pressure sensor and the accelerator pedal pressure sensor, and controls the opening and closing states of the overflow valve, the pressure increasing valve and the pressure reducing valve and the rotating speed of the motor pump.

Further, the first three-way valve is a valve with one inlet and two outlets.

Further, the second three-way valve is a valve with two inlets and one outlet.

Further, the third three-way valve is a valve with one inlet and two outlets.

Further, the fifth three-way valve is a valve with two inlets and one outlet.

Further, the fourth three-way valve is a valve with one inlet and two outlets.

Furthermore, the vehicle speed sensor is used for collecting vehicle speed information and transmitting the vehicle speed information to the main controller, when the vehicle speed is zero, the main controller controls the plunger pump clutch device to realize a combination state, and only when the accelerator pedal pressure sensor transmits a signal that the accelerator pedal is stepped to the main controller, the main controller controls the plunger pump clutch device to realize a separation state; when the vehicle speed is not zero, the main controller receives a brake pedal treaded signal sent by the brake pedal pressure sensor, controls the plunger pump clutch device to realize a combination state, receives a brake pedal released signal sent by the brake pedal pressure sensor, and controls the plunger pump clutch device to realize a separation state; when the pressure of the brake pedal is greater than zero, the brake pedal is stepped, and when the pressure of the brake pedal is equal to zero, the brake pedal is released; the pressure of the accelerator pedal is greater than zero, namely the accelerator pedal is pressed, and the pressure of the accelerator pedal is equal to zero, namely the accelerator pedal is released.

Further, the accumulator pressure sensor is used for monitoring the pressure in the accumulator, the pressure has an upper limit and a lower limit, the upper limit is controlled by the overflow valve, and the lower limit is controlled by the plunger pump and the motor pump.

Further, the wheel cylinder pressure sensor is used for monitoring the pressure in a wheel cylinder, and the pressure is controlled by a pressure increasing valve and a pressure reducing valve; the magnitude of the braking force is controlled by controlling the pressure in the wheel cylinder to adjust the wheel slip ratio to maximize the adhesion coefficient of the wheel.

Furthermore, the plunger pump clutch device controls the connection between the combination sleeve and the transmission output shaft driving gear combination gear ring through the clutch solenoid valve so that the transmission output shaft driving gear and the transmission output shaft spline hub synchronously rotate, the transmission output shaft driving gear is driven to rotate, the synchronizer is arranged between the transmission output shaft spline hub and the transmission output shaft driving gear combination gear ring, the combination of the transmission output shaft spline hub and the transmission output shaft driving gear combination gear ring is ensured, and the transmission output shaft driving gear drives the transmission output shaft driven gear to rotate, so that the plunger pump is driven to work.

Further, the plunger pump is a swash plate type axial plunger pump, including: the oil distribution disc comprises a return spring, a swash plate guide cover electromagnetic valve, a swash plate, a plunger cylinder body, an oil distribution disc and a plunger pump rotor; the oil distribution disc is characterized in that the return spring is positioned on one side, without the swash plate, of the swash plate guide cover and is connected with the swash plate guide cover, the electromagnetic valve of the swash plate guide cover is connected with the swash plate guide cover on one side with the swash plate, the swash plate guide cover is sleeved on a plunger pump rotor in an empty mode, the swash plate is tightly attached to the swash plate guide cover and is sleeved on the plunger pump rotor in an empty mode, six plungers uniformly distributed on the circumference of the swash plate are respectively connected with the plunger cylinder body, the plunger cylinder body is connected with the plunger pump rotor through splines and rotates synchronously, and the oil distribution disc tightly attached to the plunger cylinder body is sleeved on the plunger pump rotor in an empty mode.

The invention relates to a control method of an energy recovery system for assisting brake-by-wire, which is based on the system and comprises the following steps:

1) the main controller respectively receives information collected by a vehicle speed sensor, an accelerator pedal pressure sensor and a brake pedal sensor, and controls the working state of the plunger pump clutch device according to the received information;

2) the main controller receives pressure information acquired by the pressure sensor of the energy accumulator, when the pressure value exceeds an upper threshold value, the main controller controls the overflow valve to be opened, the motor pump does not work, so that part of high-pressure oil directly returns to the oil storage tank without flowing through the wheel cylinder, and the upper threshold value is the limit pressure which can be born by the energy accumulator; when the pressure value is smaller than the lower threshold, the main controller controls the overflow valve to close, the motor pump works to pressurize the energy accumulator, the lower threshold is the lowest required pressure in the energy accumulator, and when the pressure value is between the upper threshold and the lower threshold, the main controller controls the overflow valve to close, and the motor pump does not work;

3) when the brake pedal is stepped on, the main controller calculates the required theoretical wheel cylinder pressure according to the brake pedal pressure, receives pressure information collected by the wheel cylinder pressure sensor and judges the pressure information, and when the pressure in the wheel cylinder is smaller than the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to be opened, the pressure reducing valve to be closed and supplements the pressure in the wheel cylinder; when the pressure in the wheel cylinder is equal to the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to close, the pressure reducing valve to close, and at the moment, the pressure in the wheel cylinder is the ideal pressure; when the pressure in the wheel cylinder is larger than the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve to be closed, the pressure reducing valve to be opened and the pressure in the wheel cylinder to be released, so that the wheel cylinder pressure is controlled to be kept near the calculated theoretical wheel cylinder pressure.

Further, the step 1) of controlling the working state of the plunger pump clutch device by the main controller specifically includes the following steps:

11) the main controller receives a vehicle ignition signal, when the vehicle is in a flameout state, the main controller controls a clutch electromagnetic valve of the plunger pump clutch device to enable the combination sleeve to be combined with a transmission output shaft driving gear combination gear ring for a long time, the pressure reducing valve is always kept in a closed state, and the pressure increasing valve is always kept in an open state;

12) when the vehicle is in an ignition state and the vehicle speed is zero, the main controller controls a clutch solenoid valve of the plunger pump clutch device to enable the combination sleeve to be combined with the transmission output shaft driving gear combination gear ring, the pressure reducing valve is closed, and the pressure increasing valve is opened, so that the plunger pump is controlled to work;

13) when the vehicle is in an ignition state, the main controller receives a signal that the accelerator pedal is stepped on and sent by the accelerator pedal sensor, and controls a clutch electromagnetic valve of the plunger pump clutch device to enable the coupling sleeve to be separated from a transmission output shaft driving gear coupling gear ring, so that the plunger pump is controlled to stop working;

14) when the vehicle is in an ignition state, and the vehicle speed is zero and the accelerator pedal is stepped on, the main controller controls a clutch electromagnetic valve of the plunger pump clutch device to separate a combination sleeve from a transmission output shaft driving gear combination gear ring, so as to control the plunger pump to stop working;

15) when the vehicle is in an ignition state and the vehicle speed is not zero, the main controller receives a signal of the brake pedal sensor to control the working state of the plunger pump clutch device.

Further, the step 12) of controlling the plunger pump clutch device to be in the engaged state by the main controller so as to control the plunger pump to work specifically includes the following steps:

121) the main controller enables the combination sleeve to be combined with the transmission output shaft driving gear combination gear ring by controlling the clutch electromagnetic valve;

122) the transmission output shaft and the transmission output shaft driving gear synchronously rotate;

123) the driving gear of the output shaft of the speed changer is meshed with the driven gear of the output shaft of the speed changer and drives the driven gear of the output shaft of the speed changer to rotate at a certain transmission ratio;

124) the driven gear of the output shaft of the speed changer is connected with the rotor of the plunger pump through a spline, so that the driven gear of the output shaft of the speed changer and the rotor of the plunger pump synchronously rotate, the plunger pump sucks oil from an oil storage tank with low oil pressure, and high-pressure oil is released into an energy accumulator.

Further, the step 15) of the main controller receiving the signal of the brake pedal sensor to control the working state of the plunger pump clutch device specifically includes the following steps:

151) the main controller receives a signal transmitted by the brake pedal pressure sensor, and if the brake pedal is stepped, the main controller controls the clutch solenoid valve to enable the combination sleeve to be combined with the transmission output shaft driving gear combination gear ring, so that the plunger pump is controlled to work;

152) the main controller receives a signal transmitted by the brake pedal pressure sensor, and if the brake pedal is released, the main controller controls the clutch electromagnetic valve to separate the combination sleeve from the transmission output shaft driving gear combination gear ring, so that the plunger pump is controlled to stop working.

Further, the pressure build-up process in the operation of the plunger pump in step 151) is as follows:

1511) the plunger pump is a swash plate type axial plunger pump, the number of plungers of the swash plate type axial plunger pump is a, the diameter of the plungers is D, the included angle between the plane of a swash plate and the normal plane of the axis of a rotor of the plunger pump is alpha, and the rotating diameter of the axis of the plunger around the axis of the rotor of the plunger pump is D;

1512) the starting working time t of the swash plate type axial plunger pump is 0, and the pressure of the energy accumulator is P at the moment₀Volume of gas in accumulator is V₀Gas density is rho₀And the pressure of the energy accumulator is higher than a lower threshold and lower than an upper threshold, and the following pressure formula is obtained according to the working characteristics of the swash plate type axial plunger pump:

where n is the wheel speed, i₀Is the main reducer transmission ratio i₁Is the transmission ratio of the clutch device of the plunger pump, t is the working time of the swash plate type plunger pump, m₀Is the mass of gas in the accumulator.

The pressure of the energy accumulator is higher than the lower threshold and lower than the upper threshold, and the pressure of the energy accumulator is influenced by the included angle between the normal plane of the swash plate axis and the normal plane of the plunger pump rotor axis, the wheel rotating speed and the working time of the plunger pump.

Further, in the electronic hydraulic brake system assembly and the plunger pump high-pressure loop assembly, the oil path can be divided into two parts according to whether the oil path is directly connected with the oil storage tank or not, one part is called a low-pressure oil path which is directly communicated with the oil storage tank, hydraulic oil in the low-pressure oil path is called low-pressure oil, the rest oil paths are collectively called high-pressure oil paths, and hydraulic oil in the high-pressure oil paths is collectively called high-pressure oil.

The invention has the beneficial effects that:

the energy-saving brake device has the function of saving energy, can drive the wheels of the automobile to rotate by utilizing the kinetic energy of the automobile through the ground friction force when the automobile is braked, then drives the output shaft of the speed changer to rotate through the automobile transmission system, and then drives the plunger pump to work through the plunger pump clutch device, so as to supplement the energy of the energy accumulator, and can greatly reduce the energy consumed when the automobile is braked on a long downhill or decelerated.

The automobile brake system has the function of auxiliary braking, can utilize the kinetic energy of the automobile to brake under the condition that the automobile service brake system fails, the faster the rotating speed of the wheel is, the larger the braking force can be provided, and the slower the rotating speed of the wheel is, the smaller the braking force can be provided, and the automobile can be rapidly braked and stopped by the characteristic that the kinetic energy of the automobile and the braking force are in negative correlation. Therefore, the invention also has the function of inhibiting the slope slipping speed of the automobile, can utilize the kinetic energy of the automobile to brake when the parking brake system fails or the automobile slips when a driver stops the automobile without flameout, can effectively reduce the slope slipping speed of the automobile, and can solve the problem and reduce the slope slipping harm for the driver with sufficient time.

Drawings

FIG. 1 is a schematic diagram of the architecture of the system of the present invention;

FIG. 2 is a schematic view of a plunger pump clutching device of the present invention;

FIG. 3 is a schematic view of the plunger pump;

FIG. 4 is a cross-sectional view of FIG. 3;

FIG. 5 is a block diagram of the principle flow of the method of the present invention;

in fig. 1: 1-an oil storage tank, 2-a first three-way valve, 3-a fifth three-way valve, 4-a pressure reducing valve, 5-a wheel cylinder, 6-a second one-way check valve, 7-a plunger pump, 8-a fourth one-way check valve, 9-a motor pump, 10-a third one-way check valve, 11-a first one-way check valve, 12-an overflow valve, 13-a pressure increasing valve, 14-a fourth three-way valve, 15-a wheel cylinder pressure sensor, 16-an energy accumulator, 17-an energy accumulator pressure sensor, 18-a second three-way valve and 19-a third three-way valve;

in fig. 2: 7-a plunger pump, 20-a transmission output shaft, 21-a clutch electromagnetic valve, 22-a synchronizer, 23-a transmission output shaft driving gear, 24-a transmission output shaft spline hub, 25-a combination sleeve, 26-a transmission output shaft driving gear combination gear ring and 27-a transmission output shaft driven gear;

in fig. 3: 30-a swash plate guide cover electromagnetic valve, 31-a swash plate, 32-a plunger, 33-a plunger cylinder body, 34-an oil distribution disc and 35-a plunger pump rotor.

Detailed Description

In order to facilitate understanding of those skilled in the art, the present invention will be further described with reference to the following examples and drawings, which are not intended to limit the present invention.

Referring to fig. 1 to 4, an energy recovery system for assisting brake-by-wire according to the present invention includes: the system comprises an accelerator pedal, an accelerator pedal pressure sensor, a vehicle speed sensor, a brake pedal pressure sensor, an electronic hydraulic brake system assembly, a plunger pump clutch device, a plunger pump high-pressure loop assembly and a main controller; wherein the content of the first and second substances,

the accelerator pedal is connected with an accelerator pedal pressure sensor;

the accelerator pedal pressure sensor is connected with the main controller;

the vehicle speed sensor is connected with the main controller;

the brake pedal is connected with a brake pedal pressure sensor;

the brake pedal pressure sensor is connected with the main controller;

the electro-hydraulic brake system assembly includes: the device comprises an oil storage tank 1, a motor pump 9, a first one-way check valve 11, a third one-way check valve 10, an accumulator 16, an accumulator pressure sensor 17, an overflow valve 12, a pressure increasing valve 13, a pressure reducing valve 4, a wheel cylinder 5, a wheel cylinder pressure sensor 15, a first three-way valve 2, a second three-way valve 18, a third three-way valve 19, a fourth three-way valve 14 and a fifth three-way valve 3; the overflow valve 12, the booster valve 13, the pressure reducing valve 4 and the motor pump 9 are all connected with and controlled by a main controller; the energy accumulator pressure sensor 17 and the wheel cylinder pressure sensor 15 are both connected with the main controller; the oil storage tank 1 is connected with an oil inlet of the first three-way valve 2 through an oil pipe, a first oil outlet of the first three-way valve 2 is connected with the motor pump 9 through an oil pipe, and a second oil outlet of the first three-way valve 2 is closed; a first one-way check valve 11 is arranged on an oil pipe between the first three-way valve 2 and the motor pump 9, so that hydraulic oil flows to the motor pump 9 from the first three-way valve 2; the motor pump 9 is connected with a first oil inlet of a second three-way valve 18 through an oil pipe, a second oil inlet of the second three-way valve 18 is closed, a third one-way check valve 10 is installed between the motor pump 9 and the second three-way valve 18, hydraulic oil flows from the motor pump 9 to the second three-way valve 18, an oil outlet of the second three-way valve 18 is connected with an energy accumulator 16 through an oil pipe, the energy accumulator 16 is connected with an oil inlet of a third three-way valve 19 through an oil pipe, an energy accumulator pressure sensor 17 is installed in the oil pipe between the third three-way valve 19 and the energy accumulator 16, a first oil outlet of the third three-way valve 19 is connected with an overflow valve 12 through an oil pipe, the overflow valve 12 is connected with a first oil inlet of a fifth three-way valve 3 through an oil pipe, a second oil outlet of the third three-way valve 19 is connected with a pressure increasing valve 13 through an oil pipe, the pressure increasing valve 13 is connected with an oil inlet of a fourth three-way valve 14 through an oil pipe, a first oil outlet of the fourth three-way valve 14 is connected with a pressure reducing valve 4 through an oil pipe, a second oil outlet of the fourth three-way valve 14 is connected with the wheel cylinder 5 through an oil pipe, a wheel cylinder pressure sensor 15 is installed in the oil pipe between the fourth three-way valve 14 and the wheel cylinder 5, the pressure reducing valve 4 is connected with a second oil inlet of the fifth three-way valve 3 through an oil pipe, and an oil outlet of the fifth three-way valve 3 is connected with the oil storage tank 1 through an oil pipe;

the plunger pump clutch device comprises: a transmission output shaft spline hub 24, a transmission output shaft driving gear 23, a transmission output shaft driving gear combined gear ring 26, a synchronizer 22, a transmission output shaft driven gear 27, a combined sleeve 25 and a clutch electromagnetic valve 21; the coupling sleeve 25 rotates synchronously with the transmission output shaft spline hub 24 and slides on the transmission output shaft spline hub 24 along the axial direction of the transmission output shaft 20, the transmission output shaft driving gear coupling ring gear 26 is tightly attached to the transmission output shaft driving gear 23 and rotates synchronously, the synchronizer 22 is arranged between the transmission output shaft driving gear coupling ring gear 25 and the transmission output shaft spline hub 24, and the transmission output shaft driving gear 23 is meshed with the transmission output shaft driven gear 27; the clutch electromagnetic valve 21 is connected with the outer ring of the combination sleeve 25;

plunger pump high pressure return circuit assembly includes: a plunger pump 7, a second one-way check valve 6, a fourth one-way check valve 8; a low-pressure inlet of the plunger pump 7 is connected with a second oil outlet of the first three-way valve 2 through an oil pipe, and a high-pressure outlet of the plunger pump 7 is connected with a second oil inlet of the second three-way valve 18 through an oil pipe; the second one-way check valve 6 is arranged between the first three-way valve 2 and the plunger pump 7 and is used for enabling hydraulic oil to flow from the first three-way valve 2 to the plunger pump 7; the fourth one-way check valve 8 is arranged between the plunger pump 7 and the second three-way valve 18 and is used for enabling hydraulic oil to flow from the plunger pump 7 to the second three-way valve 18; the rotor of the plunger pump 7 is coaxially connected with a transmission output shaft driven gear 27;

the main controller is connected with an overflow valve 12, a pressure increasing valve 13, a pressure reducing valve 3, a motor pump 9, an energy accumulator pressure sensor 17, a wheel cylinder pressure sensor 15, a vehicle speed sensor, a brake pedal pressure sensor and an accelerator pedal pressure sensor through connecting wires; the main controller receives signals of the motor pump 9, the energy accumulator pressure sensor 17, the wheel cylinder pressure sensor 15, the vehicle speed sensor, the brake pedal pressure sensor and the accelerator pedal pressure sensor, and controls the opening and closing states of the overflow valve 12, the pressure increasing valve 13 and the pressure reducing valve 3 and the rotating speed of the motor pump 9.

In a preferred example, the first three-way valve 2 is a valve with one inlet and two outlets; the second three-way valve 18 is a two-in one-out valve; the third three-way valve 19 is a valve with one inlet and two outlets; the fifth three-way valve 3 is a valve with two inlets and one outlet; the fourth three-way valve 14 is a one-in two-out valve.

In a preferred example, the vehicle speed sensor is used for acquiring vehicle speed information and transmitting the vehicle speed information to the main controller, when the vehicle speed is zero, the main controller controls the plunger pump clutch device to realize a combination state, and only when the accelerator pedal pressure sensor transmits a signal that the accelerator pedal is stepped to the main controller, the main controller controls the plunger pump clutch device to realize a separation state; when the vehicle speed is not zero, the main controller receives a brake pedal treaded signal sent by the brake pedal pressure sensor, controls the plunger pump clutch device to realize a combination state, receives a brake pedal released signal sent by the brake pedal pressure sensor, and controls the plunger pump clutch device to realize a separation state; when the pressure of the brake pedal is greater than zero, the brake pedal is stepped, and when the pressure of the brake pedal is equal to zero, the brake pedal is released; the pressure of the accelerator pedal is greater than zero, namely the accelerator pedal is pressed, and the pressure of the accelerator pedal is equal to zero, namely the accelerator pedal is released.

In the preferred example, the accumulator pressure sensor 17 is used to monitor the pressure in the accumulator 16, which has an upper limit controlled by the relief valve 12 and a lower limit controlled by the plunger pump 7 and the motor pump 9.

In a preferred example, the wheel cylinder pressure sensor 15 is used to monitor the pressure in the wheel cylinder 5, which is controlled by the pressure increasing valve 13 and the pressure reducing valve 4; the magnitude of the braking force is controlled by controlling the pressure in the wheel cylinder 5 to adjust the wheel slip ratio to maximize the adhesion coefficient of the wheel.

In a preferred example, the plunger pump clutch device controls the connection between the coupling sleeve 25 and the transmission output shaft driving gear coupling gear ring 26 through the clutch solenoid valve 21, so that the transmission output shaft driving gear 23 and the transmission output shaft spline hub 24 synchronously rotate, and the transmission output shaft driving gear 23 is driven to rotate, the synchronizer 22 is located between the transmission output shaft spline hub 24 and the transmission output shaft driving gear coupling gear ring 26, and the coupling between the transmission output shaft spline hub 24 and the transmission output shaft driving gear coupling gear ring 26 is ensured, and the transmission output shaft driving gear 23 drives the transmission output shaft driven gear 27 to rotate, so that the plunger pump 7 is driven to work.

In a preferred example, the plunger pump 7 is a swash plate type axial plunger pump, comprising: a return spring 28, a swash plate guide cover 29, a swash plate guide cover solenoid valve 30, a swash plate 31, a plunger 32, a plunger cylinder block 33, an oil distribution pan 34, and a plunger pump rotor 35; the return spring 28 is positioned on the side without the swash plate of the swash plate guide cover 29 and is connected with the swash plate guide cover 29, the swash plate guide cover electromagnetic valve 30 is connected with the swash plate guide cover 29 on the side with the swash plate, the swash plate guide cover 29 is sleeved on the plunger pump rotor 35 in an empty way, the swash plate 31 is tightly attached to the swash plate guide cover 29 and is sleeved on the plunger pump rotor 35 in an empty way, the swash plate 31 is respectively connected with the plunger cylinder block 33 through six plungers 32 which are uniformly distributed on the circumference, the plunger cylinder block 33 is connected with the plunger pump rotor 35 through a spline and rotates synchronously, and the oil distribution disc 34 tightly attached to the plunger cylinder block 33 is sleeved on the plunger pump rotor 35 in an empty way.

Referring to fig. 5, the control method of the energy recovery system for assisting brake-by-wire according to the present invention, based on the above system, includes the following steps:

1) the main controller respectively receives information collected by a vehicle speed sensor, an accelerator pedal pressure sensor and a brake pedal sensor, and controls the working state of the plunger pump clutch device according to the received information;

the main controller controls the working state of the plunger pump clutch device to specifically comprise the following steps:

11) the main controller receives a vehicle ignition signal, when the vehicle is in a flameout state, the main controller controls the clutch electromagnetic valve 21 of the plunger pump clutch device to enable the combination sleeve 25 to be combined with the transmission output shaft driving gear combination gear ring 26 for a long time, the pressure reducing valve 4 is always kept in a closed state, and the pressure increasing valve 13 is always kept in an open state;

12) when the vehicle is in an ignition state and the vehicle speed is zero, the main controller controls a clutch electromagnetic valve 21 of the plunger pump clutch device to enable a combination sleeve 25 to be combined with a transmission output shaft driving gear combination gear ring 26, a pressure reducing valve 4 is closed, a pressure increasing valve 13 is opened, and therefore the plunger pump 7 is controlled to work;

13) when the vehicle is in an ignition state, the main controller receives a signal that the accelerator pedal is stepped on and sent by the accelerator pedal sensor, and controls the clutch electromagnetic valve 21 of the plunger pump clutch device to separate the combination sleeve 25 from the transmission output shaft driving gear combination gear ring 26, so as to control the plunger pump 7 to stop working;

14) when the vehicle is in an ignition state, and the vehicle speed is zero and the accelerator pedal is stepped on, the main controller controls a clutch electromagnetic valve 21 of the plunger pump clutch device to separate a combination sleeve 25 from a transmission output shaft driving gear combination gear ring 26, so as to control the plunger pump 7 to stop working;

15) when the vehicle is in an ignition state and the vehicle speed is not zero, the main controller receives a signal of the brake pedal sensor to control the working state of the plunger pump clutch device.

The main controller controls the plunger pump clutch device to be in a combined state so as to control the plunger pump 7 to work, and the method specifically comprises the following steps:

121) the main controller enables the combination sleeve 25 to be combined with the transmission output shaft driving gear combination gear ring 26 by controlling the clutch electromagnetic valve 21;

122) the transmission output shaft 20 rotates synchronously with the transmission output shaft drive gear 23;

123) the transmission output shaft driving gear 23 is meshed with the transmission output shaft driven gear 27 and drives the transmission output shaft driven gear 27 to rotate at a certain transmission ratio;

124) the transmission output shaft driven gear 27 is connected with the rotor of the plunger pump 7 through a spline, so that the transmission output shaft driven gear 27 and the rotor of the plunger pump 7 rotate synchronously, the plunger pump 7 sucks oil from the oil storage tank 1 with low oil pressure, and releases high-pressure oil to the energy accumulator 16.

The main controller receives a signal of a brake pedal sensor to control the working state of the plunger pump clutch device, and the method specifically comprises the following steps:

151) the main controller receives a signal transmitted by the brake pedal pressure sensor, and if the brake pedal is stepped, the main controller controls the clutch electromagnetic valve 21 to enable the combination sleeve 25 to be combined with the transmission output shaft driving gear combination gear ring 26, so that the plunger pump 7 is controlled to work;

152) the master controller receives the signal from the brake pedal pressure sensor, and if the brake pedal is released, the master controller controls the clutch solenoid valve 21 to separate the coupling sleeve 25 from the transmission output shaft driving gear coupling ring gear 26, so as to control the plunger pump 7 to stop working.

The pressure building process of the plunger pump 7 during operation is as follows:

1511) the plunger pump 7 is a swash plate type axial plunger pump, the number of plungers 32 of the swash plate type axial plunger pump is a, the diameter of the plungers 32 is D, the included angle between the plane of the swash plate 31 and the normal plane of the axis of the plunger pump rotor 35 is alpha, and the rotating diameter of the axis of the plungers 32 around the axis of the plunger pump rotor 35 is D;

1512) the starting working time t of the swash plate type axial plunger pump is 0, and the pressure of the energy accumulator 16 is P at the moment₀Volume of gas in accumulator 16 is V₀Gas density is rho₀When the pressure of the accumulator 16 is higher than the lower threshold and lower than the upper threshold, the following pressure formula is obtained according to the operating characteristics of the swash plate type axial plunger pump:

where n is the wheel speed, i₀Is the main reducer transmission ratio i₁Is the transmission ratio of the clutch device of the plunger pump, t is the working time of the swash plate type plunger pump, m₀Is the mass of gas in the accumulator.

The pressure of the accumulator 16 is higher than the lower threshold and lower than the upper threshold, and the pressure of the accumulator 16 is influenced by the included angle between the normal plane of the axis of the swash plate 31 and the normal plane of the axis of the plunger pump rotor 35, the rotating speed of wheels and the working time of the plunger pump 7.

2) The main controller receives pressure information collected by the energy accumulator pressure sensor 17, when the pressure value exceeds an upper threshold value, the main controller controls the overflow valve 12 to be opened, the motor pump 9 does not work, so that part of high-pressure oil directly returns to the oil storage tank 1 without flowing through the wheel cylinder 5, and the upper threshold value is the limit pressure which can be borne by the energy accumulator 16; when the pressure value is smaller than the lower threshold value, the main controller controls the overflow valve 12 to close, the motor pump 9 works to pressurize the energy accumulator 16, the lower threshold value is the lowest required pressure in the energy accumulator 16, and when the pressure value is between the upper threshold value and the lower threshold value, the main controller controls the overflow valve 12 to close, and the motor pump 9 does not work;

3) when the brake pedal is stepped on, the main controller calculates the required theoretical wheel cylinder pressure according to the brake pedal pressure, receives the pressure information collected by the wheel cylinder pressure sensor 15 and judges the pressure information, and when the pressure in the wheel cylinder 5 is smaller than the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve 13 to be opened, the pressure reducing valve 4 to be closed and supplements the pressure in the wheel cylinder 5; when the pressure in the wheel cylinder 5 is equal to the theoretical wheel cylinder pressure, the main controller controls the pressure increasing valve 13 to be closed, the pressure reducing valve 4 to be closed, and at the moment, the pressure in the wheel cylinder 5 is the ideal pressure; when the pressure in the wheel cylinder 5 is larger than the theoretical wheel cylinder pressure, the main controller controls the pressure-increasing valve 13 to close, the pressure-decreasing valve 4 to open, and the pressure in the wheel cylinder 5 is released, thereby controlling the wheel cylinder pressure to be maintained in the vicinity of the calculated theoretical wheel cylinder pressure.

In addition, in the electro-hydraulic brake system assembly and the plunger pump high-pressure circuit assembly, the oil path may be divided into two parts according to whether the oil path is directly connected with the oil reservoir 1, one part is called a low-pressure oil path which is directly communicated with the oil reservoir 1, the hydraulic oil in the low-pressure oil path is called low-pressure oil, the other oil paths are collectively called high-pressure oil paths, and the hydraulic oil in the high-pressure oil path is collectively called high-pressure oil.

While the invention has been described in terms of its preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.