CN110203028A - A kind of hydro-pneumatic suspension system having anti-roll function and its control method - Google Patents

Abstract

The invention discloses an oil-pneumatic suspension system with an anti-rolling function, comprising: a suspension, and a vehicle frame, which is arranged above the suspension; a first oil-pneumatic spring, one end of which is fixedly connected to the front end of the suspension; The spring includes a first piston rod. One end of the first piston rod is fixedly connected to one side of the frame, and the other end divides the first oil-pneumatic spring into a first upper cavity and a first lower cavity; Symmetrically arranged, one end is fixedly connected to the front end of the suspension, the second oil-pneumatic spring includes a second piston rod, one end of the second piston rod is fixedly connected to the other side of the vehicle frame, and the other end divides the second oil-pneumatic spring into the second upper chamber and the second Two lower chambers; the third oil-gas spring, one end of which is fixedly connected to the rear end of the suspension, the third oil-gas spring includes a third piston rod, one end of the third piston rod is fixedly connected to the vehicle frame, and is arranged on the same side as the first piston rod; The fourth oil-pneumatic spring is arranged symmetrically with the third oil-pneumatic spring, one end of which is fixedly connected to the rear end of the suspension, and the fourth oil-pneumatic spring includes a fourth piston rod.

Description

A hydro-pneumatic suspension system with anti-roll function and its control method

technical field

The invention relates to the field of automobile driving, in particular to an oil-pneumatic suspension system with an anti-roll function and a control method thereof.

Background technique

With the development of the automobile industry, vehicles are gradually used in more fields, and people's requirements for vehicles are getting higher and higher. As an important component of a car, the vehicle suspension system plays an important role in the ride comfort and driving safety of the vehicle. It plays a vital role. As a special suspension form, the oil-pneumatic suspension uses air pressure and hydraulic control technology to change and adjust the stiffness and damping characteristics of the suspension. After reasonable parameter settings, the oil-pneumatic suspension system can achieve When changing, the natural frequency of the vehicle is guaranteed to remain basically unchanged; the damping characteristics of the suspension can be changed by using electro-hydraulic control technology, so that the suspension damping under different load conditions can be optimal, and the ride comfort of the vehicle can be improved; through hydraulic control technology, Control the expansion and contraction of the oil-pneumatic cylinder, change the height of the vehicle and improve the off-road performance of the vehicle; control the expansion and contraction of the oil-pneumatic cylinder through the hydraulic control system, and adjust the posture of the vehicle body; the oil-pneumatic suspension has good nonlinear damping characteristics, simple structure and reliable performance And other performance advantages, in recent years, more manufacturers have paid attention to and applied this type of suspension.

At present, some heavy-duty vehicles, engineering vehicles and some military vehicles have been equipped with oil-pneumatic suspension systems, but there is insufficient research on oil-pneumatic suspension systems in terms of vehicle anti-rolling, and there is no clear solution. This patent solves the problem very well. the problem.

Contents of the invention

In order to solve the shortcomings of the current technology, the present invention provides an oil-pneumatic suspension system with an anti-rolling function, through the adjustment of the hydraulic pipeline of the oil-pneumatic suspension, the vehicle body height can be kept constant during parking and driving.

The invention can also independently adjust the height of the front axle and the height of the rear axle, so that the vehicle can automatically level the vehicle body and improve the passability and off-road performance of the vehicle.

The invention also provides a control method of the oil-pneumatic suspension system with the function of anti-rolling, which can adjust the oil intake amount of the oil-pneumatic spring according to the height difference between the front and rear axles, so that the height of the front and rear axles can be stabilized and consistent.

The technical solution provided by the present invention is: an oil-pneumatic suspension system with anti-roll function, including:

suspension, and

a vehicle frame disposed above the suspension;

The first oil-pneumatic spring, one end of which is fixedly connected to the front end of the suspension, the first oil-pneumatic spring includes a first piston rod, one end of the first piston rod is fixedly connected to one side of the vehicle frame, and the other end connects the The first oil and gas spring is divided into a first upper cavity and a first lower cavity;

The second oil-pneumatic spring is arranged symmetrically with the first oil-pneumatic spring, and one end is fixedly connected to the front end of the suspension. The second oil-pneumatic spring includes a second piston rod, and one end of the second piston rod is fixedly connected to the vehicle. On the other side of the frame, the other end divides the second oil-gas spring into a second upper cavity and a second lower cavity;

The third oil-pneumatic spring, one end of which is fixedly connected to the rear end of the suspension, the third oil-pneumatic spring includes a third piston rod, one end of the third piston rod is fixedly connected to the vehicle frame, and is connected with the first piston rod same side setting;

The fourth oil-pneumatic spring is arranged symmetrically with the third oil-pneumatic spring, one end of which is fixedly connected to the rear end of the suspension, and the fourth oil-pneumatic spring includes a fourth piston rod, which is arranged on the same side as the second piston rod ;

a first pipeline, the two ends of which communicate with the first upper chamber and the second lower chamber respectively;

a second pipeline, the two ends of which communicate with the second upper chamber and the first lower chamber respectively;

a third pipeline, the two ends of which are respectively connected to the third oil-pneumatic spring and the fourth oil-pneumatic spring;

The first front axle hydraulic control valve communicates with the second pipeline;

a second front axle hydraulic control valve, which communicates with the first pipeline and the first front axle hydraulic control valve;

Rear axle hydraulic control valve, which communicates with the third pipeline;

an oil tank, the oil outlet of which is respectively connected to the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve;

a hydraulic pump, the oil inlet of which is respectively connected to the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve;

A controller is connected to and controls the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve respectively.

Preferably, it also includes:

a first hydraulic control check valve, which is arranged between the second pipeline and the first front axle hydraulic control valve;

a second hydraulic control check valve, which is arranged between the first pipeline and the second front axle hydraulic control valve;

A third hydraulically controlled one-way valve is arranged between the third pipeline and the hydraulic control valve of the rear axle.

Preferably, it also includes:

An increase and decrease control valve is arranged at the oil inlet of the hydraulic pump.

Preferably,

The first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve are all three-position four-way electromagnetic reversing valves.

Preferably, it also includes:

a suspension connecting plate, which is arranged on the suspension;

Four vehicle body height sensors are respectively arranged at the four corners of the vehicle body, one end of which is connected to the vehicle frame, and the other end is connected to the suspension connecting plate.

Preferably, it also includes:

The increase and decrease control valve is a two-position three-way electromagnetic reversing valve, one end of which communicates with the oil outlet of the fuel tank and the oil inlet of the hydraulic pump, and the other end communicates with the hydraulic control valve.

Preferably, it also includes:

An overflow valve, one end of which communicates with the oil outlet of the fuel tank, and the other end communicates with the pressure increase and decrease control valve, and communicates with the hydraulic control valve.

Preferably,

The vehicle frame includes two longitudinal beams and two cross beams;

Wherein, the beam is vertically arranged with the longitudinal beam;

The oil-gas spring is fixedly connected with the longitudinal beam.

A method for controlling a hydropneumatic suspension system with an anti-roll function, comprising:

When the vehicle body height sensor detects that the heights of the front and rear axles are inconsistent, adjust the hydraulic control valve at the corresponding position of the low-height axle and the oil flow of the corresponding oil and gas spring to meet:

Among them, λ1 is the _first correction coefficient, h is the target height, Δh is the absolute value of the height difference between the front and rear axles, v is the vehicle speed during adjustment, V is the volume of the oil-pneumatic spring, and a is the oil in the corresponding oil-pneumatic spring Height, S is the distance between the frame and the axle, _Q0 is the rated oil flow of the hydraulic pump.

Beneficial effects of the present invention: the present invention can realize self-regulation of the roll condition of the vehicle by installing an oil-pneumatic suspension system with an anti-roll function, and through automatic adjustment of the hydraulic pipeline of the oil-pneumatic suspension, the The elongation heights of the four oil-pneumatic springs installed above the four wheels are equal to keep the height of the vehicle body unchanged during parking and driving, especially when the vehicle undergoes a large axle load transfer such as steering, so as to ensure that the vehicle is in such a state The body does not tilt under working conditions, which improves the handling stability of the vehicle in steering, braking and other working conditions; at the same time, the height of the front axle and the height of the rear axle can be adjusted independently. Off-road performance, the ability to achieve certain specific actions according to the purpose. The present invention also provides a method for controlling an oil-pneumatic suspension system with an anti-roll function, which can adjust the amount of oil entering the corresponding oil-pneumatic spring according to the height difference between the front and rear axles (that is, adjust the amount of oil pumped out by the hydraulic pump), so that The height of the front and rear axles is stable and consistent.

Description of drawings

Fig. 1 is a general layout diagram of the hydro-pneumatic suspension system with anti-rolling function of the present invention.

Fig. 2 is a schematic diagram of the installation of the oil-pneumatic spring and the vehicle height sensor on the vehicle frame according to the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings, so that those skilled in the art can implement it with reference to the description.

As shown in Figures 1-2, a hydropneumatic suspension system with an anti-roll function of the present invention includes: a suspension, and a vehicle frame 110 is arranged above the suspension, including two longitudinal beams 111 and two cross beams 112, the longitudinal beam 111 and the cross beam 112 are arranged vertically. The suspension is provided with a suspension connecting plate 114, and the vehicle body height sensor 113 is installed between the vehicle frame 110 and the suspension connecting plate 114, and four vehicle height sensors are provided, respectively arranged at four corners of the vehicle frame, Measure the height of the front and rear axles separately. The upper end of the oil-pneumatic spring is connected to the vehicle frame 110 , and the lower end is connected to the suspension connecting plate 114 through a pin shaft 115 . Similarly, there are four oil and gas springs, which are symmetrically distributed before and after the longitudinal beam.

As shown in Figure 1, the oil and gas spring includes a first oil and gas spring 120, one end of which is fixedly connected to the front end of the suspension, and the first oil and gas spring 120 includes a first piston rod 123, and one end of the first piston rod 123 is fixedly connected to the front end of the suspension. One side of the vehicle frame 110 (the front end of the left longitudinal beam 111 ) and the other end divide the first oil-pneumatic spring 120 into a first upper cavity 121 and a first lower cavity 122 .

The second oil-pneumatic spring 130 is arranged symmetrically with the first oil-pneumatic spring 120, and one end is fixedly connected to the front end of the suspension. The second oil-pneumatic spring 130 includes a second piston rod 133, and one end of the second piston rod 133 is fixed Connecting to the other side of the vehicle frame (the front end of the right longitudinal beam 111 ), the other end divides the second oil-pneumatic spring 130 into a second upper cavity 131 and a second lower cavity 132 .

One end of the third oil-pneumatic spring 140 is fixedly connected to the rear end of the suspension, and the third oil-pneumatic spring 140 includes a third piston rod 143, and one end of the third piston rod 143 is fixedly connected to the vehicle frame (the left longitudinal beam 111 rear end), which is set on the same side as the first piston rod 123 , and the third piston rod 143 divides the third oil-pneumatic spring 140 into a third upper chamber 142 and a third lower chamber 141 .

The fourth oil-pneumatic spring 150 is arranged symmetrically with the third oil-pneumatic spring 140, and one end thereof is fixedly connected to the rear end of the suspension. Set on the same side, the fourth piston rod 153 divides the fourth oil-pneumatic spring 150 into a fourth upper chamber 152 and a fourth lower chamber 151 .

The two ends of the first pipeline 191 communicate with the first upper chamber 121 and the second lower chamber 132 respectively; the two ends of the second pipeline 192 communicate with the second upper chamber 131 and the first lower chamber 122 respectively; Both ends of the pipeline 193 communicate with the third oil-pneumatic spring 140 (third lower chamber 141 ) and the fourth oil-pneumatic spring 150 (fourth lower chamber 151 ), respectively. The first front axle hydraulic control valve 164 communicates with the second pipeline 192; the second front axle hydraulic control valve 165 communicates with the first front axle hydraulic control valve 191 and the first front axle hydraulic control valve 164 respectively; the rear axle hydraulic control valve 166 Connected to the third pipeline 193;

The oil outlet (T port) of the fuel tank 171 is respectively connected to the first front axle hydraulic control valve 164, the second front axle hydraulic control valve 165 and the rear axle hydraulic control valve 166; the hydraulic pump 172 oil inlet (P port) communicate with the first front axle hydraulic control valve 164, the second front axle hydraulic control valve 165 and the rear axle hydraulic control valve 166 respectively; the controller 180 is respectively connected to and controls the first front axle hydraulic control valve valve 164 , the second front axle hydraulic control valve 165 and the rear axle hydraulic control valve 166 .

The first hydraulic control check valve 161 is arranged between the second pipeline 192 and the first front axle hydraulic control valve 164; the second hydraulic control check valve 162 is arranged between the first pipeline 191 and the first front axle hydraulic control valve 164; Between the two front axle hydraulic control valves 165 ; the third hydraulic control check valve 166 is arranged between the third pipeline 193 and the rear axle hydraulic control valve 166 . The hydraulic control check valve is a valve body with a control port, which is used to control the one-way flow of oil. When the control port is not connected to high-pressure oil, the hydraulic control check valve can only flow oil in one direction. , and when the control port is connected to high-pressure oil, the hydraulic control check valve is equivalent to a pipeline connection, and the hydraulic control check valve can be conducted in both forward and reverse directions.

The increase and decrease control valve 167 is arranged at the oil inlet of the hydraulic pump 172 and is electrically connected to the controller shown.

The increase and decrease control valve 167 is a two-position three-way electromagnetic reversing valve, with two connecting ports on one side communicating with the oil return port and the oil inlet respectively, and one connecting port at the other end connecting with the front and rear axles. When the control unit judges that the system needs to adjust the height of the front axle or rear axle, the pressure increase and decrease control valve 167 is closed. The electromagnetic coil of the valve 167 is energized, the increase and decrease control valve 167 is opened, and the high-pressure oil enters the system. The height of the rear axle, if the system performs a downward action at this time, the corresponding hydraulic control valves of the front and rear axles will control the high-pressure oil to enter the control port of the hydraulic control check valve. At this time, the hydraulic control check valve communicates in reverse, and the front and rear axles The high-pressure oil in the tank flows to the oil return port through the oil return pipeline through the increase and decrease control valve 167, so as to complete the purpose of pressure relief and reduce the height of the front and rear axles.

One end of the overflow valve 168 is connected to the outlet of the oil tank 171, and the other end is connected to the increase and decrease control valve 167. The overflow valve is used to control the pressure of the hydraulic fluid in the entire system. When the oil pressure of the oil is higher than the threshold set by the relief valve, the high-pressure oil will cause the relief valve 168 to open. At this time, the high-pressure oil entering from the pressure increase and decrease control valve 167 will pass through the relief valve 168 and flow from the connected oil tank The port flows back to the oil tank, so as to ensure that the high-pressure oil in the system will not exceed the set threshold under any circumstances, and ensure the safety and normal service life of each component in the system.

The first front axle hydraulic control valve 164 , the second front axle hydraulic control valve 165 and the rear axle hydraulic control valve 166 are all three-position four-way electromagnetic reversing valves. Taking the structure of the second front axle hydraulic control valve 165 as an example, it has two working positions and a middle static position. The left end and the right end of the valve body respectively have a spring and an electromagnetic coil, in which the first electromagnet (DT1) is energized. , The second electromagnet (DT2) is de-energized, and the solenoid valve switches to the right. At this time, corresponding to the first working position, the first electromagnet (DT1) is de-energized, the second electromagnet (DT2) is energized, and the solenoid valve turns left Reversing, at this time corresponding to the second working position, the control unit (ECU) can control the power-on and power-off of the first electromagnet (DT1) and the second electromagnet (DT2) on the solenoid valve, when the first electromagnet ( DT1) and the second electromagnet (DT2) are de-energized, and the valve body is in the middle static position under the action of the springs on both sides. The control port is connected to the low-pressure oil return port T. At this time, the hydraulic control check valve has one-way flow. At this time, the hydraulic oil in the front and rear axles cannot flow out to form a closed space; when the control unit (ECU) controls the first electromagnet (DT1) is energized, and the second electromagnet (DT2) is de-energized. At this time, the first electromagnet (DT1) overcomes the spring force and pushes the solenoid valve to the right, and the first working position is turned on. At this time, the hydraulic control check valve The control port of the control port is connected with the low-pressure oil return port T, and the hydraulic control check valve is forward-guided and reverse-blocked. After entering the control valve from the P port, the high-pressure oil can enter the hydraulic system of the front and rear axles through the hydraulic control check valve in the forward direction. , to raise the height of the front and rear axles; when the control unit (ECU) controls the first electromagnet (DT1) to be de-energized, the second electromagnet (DT2) is energized, and at this time the first electromagnet (DT1) overcomes the force of the spring to Push the solenoid valve to the left, and the second working position is conducted. At this time, the high-pressure oil enters the control valve from the P port and communicates with the control of the hydraulic control check valve. The forward and reverse directions of the hydraulic control check valve can be conducted. The high-pressure oil in the hydraulic system of the rear axle can pass through the hydraulic control check valve in reverse, and flow back to the oil tank from the T port, so as to achieve the purpose of reducing the height of the front and rear axles.

The oil-pneumatic suspension system has the function of anti-rolling. Generally, when the vehicle is driving on a slope or turning, the vehicle has a lateral axle load transfer, and the suspension on one side is subject to greater compression while the other side due to the load The smaller the suspension compression is, the smaller it is, which causes the body to roll to a certain extent, and the car is in a dangerous working condition. When the axle load is transferred to the vehicle installed with this system, the oil and gas springs on the left and right sides of the front axle interact with each other. Connected arrangement, in which the lower chamber of the left oil-pneumatic spring is connected with the upper chamber of the right oil-pneumatic spring, and the upper chamber of the left oil-pneumatic spring is connected with the lower chamber of the right oil-pneumatic spring, thus ensuring that the left lower chamber of the oil-pneumatic spring is connected with the upper right chamber. The oil pressure of the chamber and the oil pressure of the upper left chamber and the lower right chamber of the oil-pneumatic spring are always kept the same, and at this time the two hydraulic control check valves are closed. The hydraulic system of the front axle is closed because the oil-pneumatic spring The piston can move up and down freely, so when the system is balanced, the oil pressure of the upper and lower chambers of the oil-pneumatic spring is the same, so because of the special connection of the left and right oil-pneumatic springs, the oil pressure of the four chambers of the left and right oil-pneumatic springs is even The same, to ensure that the extension length of the piston rod is always the same, that is, the height of the left and right beams of the frame is the same, and the frame and the body fixed on the frame are both rigid bodies, so that it can be guaranteed that when the lateral axle load transfer occurs, the vehicle will pass through The pressure transmitted by the crossbeam and the piston rod to the oil-pneumatic springs on the left and right sides of the front axle is different, and the height of the left and right sides of the vehicle body is always the same to achieve the purpose of anti-rolling and improve the driving safety of the vehicle.

This system can realize the function of freely adjusting the height of the vehicle body. When the vehicle is stationary or driving at low speed, the system can be used to automatically level the body, raise the whole body, lower the whole body, or adjust the height of the front axle and rear axle separately to realize the adjustment of the body. This function can cooperate with other devices installed on the vehicle body to achieve certain functions. The input signal of the oil-pneumatic suspension control strategy is the signal of the vehicle height sensor and the button on the console of the cab, and the output is the input value of the oil-pneumatic suspension. Oil flow and hydraulic valve switch.

In order to satisfy the driver's degree of freedom in adjusting the height of the vehicle body, the working mode of the oil-pneumatic suspension is divided into two types, namely automatic mode and manual mode. To adjust the height of the vehicle body, in the manual mode, the driver can adjust the height through the buttons of "overall raising of the body", "overall lowering of the body", "front axle down", "front axle up", "rear axle down", "rear axle up" The height of the vehicle body, the chassis controller receives the button signal through the bus, and controls the hydraulic valve and hydraulic pump according to the driver's demand to achieve a calibrated fixed speed to adjust the suspension height of the four wheels. The driver must keep pressing the button to achieve height adjustment, and once the hand is off the button, the suspension will stop at the current position. The chassis controller will detect the real-time value of the height sensor, and when the suspension has moved to the limit position, the controller will cut off the hydraulic pump and valve switch. When operating in the manual mode, the driver can press the button set to the calibration value at any current position, and the controller will set the current height position as the new default vehicle height value.

In automatic mode, PID control is used to keep the heights of the front and rear axles the same within the limit range of the suspension. In this design, the heights of both sides of the front axle are always kept the same, and the heights of both sides of the rear axle are always kept the same. Therefore, the leveling strategy In order to detect the lower side first, raise it to the same height as the higher side, and then adjust the overall height of the vehicle body to the preset value.

When adjusting the height of the vehicle body, the four vehicle body height sensors 113 first collect four vehicle body notification signals and send them to the electronic control unit 180 for processing, and control the corresponding valve body to realize functions such as vehicle body leveling, front and rear axle individual lifting, and overall lifting , the process of raising and lowering the front and rear axles will be described in detail below, and the above-mentioned various vehicle body height adjustments are all realized based on this.

The process of raising the height of the front axle:

The electronic control unit (ECU) 180 controls the pressure increase and decrease control valve 167 to open, the first electromagnet (DT1) of the front axle hydraulic control valve is energized, and the second electromagnet (DT2) is de-energized. At this time, the first electromagnet (DT1 ) against the spring force to push the solenoid valve to the right, the first working position is turned on, and at this time, the control ports of the first hydraulic control check valve 161 and the second hydraulic control check valve 162 communicate with the low-pressure oil return port T, and the liquid The control check valve leads in the forward direction and reverses in the reverse direction. The hydraulic pump 172 pumps the high-pressure hydraulic oil into the system. The axle hydraulic control valve 165 enters into the hydraulic system of the front axle through the first hydraulic control check valve 161 and the second hydraulic control check valve 162 in the forward direction, and raises the height of the front axle. Explanation of the special connection form, the left and right sides of the front axle will rise synchronously and always keep the same height;

The process of lowering the height of the front axle: the electronic control unit 180 controls the increase and decrease control valve 167 to open, the first electromagnet (DT1) of the front axle hydraulic control valve is de-energized, and the second electromagnet (DT2) is energized. At this time, the first electromagnet (DT1) overcome the spring force and push the electromagnetic valve to the left, the second working position is turned on, the hydraulic pump 172 pumps high-pressure hydraulic oil into the system, and the high-pressure oil enters the front axle from P port and flows through the pressure increase and decrease control valve The back of the hydraulic control valve is connected to the control of the hydraulic control check valve. At this time, the hydraulic control check valve can be conducted in both forward and reverse directions. Flow back to the fuel tank, so as to achieve the purpose of reducing the height of the front and rear axles.

The rear axle adopts the same hydraulic control valve and hydraulic control check valve as the front axle, and its left and right sides are also connected structures that rise and fall at the same time. The ascending and descending process is basically the same, except that the control unit controls the rear axle hydraulic control valve installed on the rear axle and the hydraulic control check valve on the rear axle, and the others are the same as the working process of the front axle.

When the vehicle body height sensor detects that the heights of the front and rear axles are inconsistent, adjust the hydraulic control valve at the corresponding position of the low-height axle and the oil flow of the corresponding oil and gas spring to meet:

Wherein, λ1 is the _first correction coefficient, h is the target height (i.e. the height corresponding to the higher height axle), unit cm; Δh is the absolute value of the height difference of the front and rear axles, unit cm; v is the vehicle speed during adjustment, The unit is km/h; V is the volume of the oil and gas spring, the unit is L; a is the oil height in the corresponding oil and gas spring, the unit is cm; S is the distance between the frame and the axle, the unit is cm; Q ₀ is the rated value of the hydraulic pump The oil output flow rate is in L/s; the oil flow rate of the oil and gas spring is adjusted by adjusting the corresponding solenoid valve and hydraulic pump.

Although the embodiment of the present invention has been disclosed as above, it is not limited to the use listed in the specification and implementation, it can be applied to various fields suitable for the present invention, and it can be easily understood by those skilled in the art Therefore, the invention is not limited to the specific details and examples shown and described herein without departing from the general concept defined by the claims and their equivalents.

Claims (9)

1. A hydropneumatic suspension system with anti-roll function, characterized in that it comprises: suspension, and a vehicle frame disposed above the suspension; The first oil-pneumatic spring, one end of which is fixedly connected to the front end of the suspension, the first oil-pneumatic spring includes a first piston rod, one end of the first piston rod is fixedly connected to one side of the vehicle frame, and the other end connects the The first oil and gas spring is divided into a first upper cavity and a first lower cavity; The second oil-pneumatic spring is arranged symmetrically with the first oil-pneumatic spring, and one end is fixedly connected to the front end of the suspension. The second oil-pneumatic spring includes a second piston rod, and one end of the second piston rod is fixedly connected to the vehicle. On the other side of the frame, the other end divides the second oil-gas spring into a second upper cavity and a second lower cavity; The third oil-pneumatic spring, one end of which is fixedly connected to the rear end of the suspension, the third oil-pneumatic spring includes a third piston rod, one end of the third piston rod is fixedly connected to the vehicle frame, and is connected with the first piston rod same side setting; The fourth oil-pneumatic spring is arranged symmetrically with the third oil-pneumatic spring, one end of which is fixedly connected to the rear end of the suspension, and the fourth oil-pneumatic spring includes a fourth piston rod, which is arranged on the same side as the second piston rod ; a first pipeline, the two ends of which communicate with the first upper chamber and the second lower chamber respectively; a second pipeline, the two ends of which communicate with the second upper chamber and the first lower chamber respectively; a third pipeline, the two ends of which are respectively connected to the third oil-pneumatic spring and the fourth oil-pneumatic spring; The first front axle hydraulic control valve communicates with the second pipeline; a second front axle hydraulic control valve, which communicates with the first pipeline and the first front axle hydraulic control valve; Rear axle hydraulic control valve, which communicates with the third pipeline; an oil tank, the oil outlet of which is respectively connected to the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve; a hydraulic pump, the oil inlet of which is respectively connected to the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve; A controller is connected to and controls the first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve respectively. 2. The hydropneumatic suspension system with anti-roll function according to claim 1, further comprising: a first hydraulic control check valve, which is arranged between the second pipeline and the first front axle hydraulic control valve; a second hydraulic control check valve, which is arranged between the first pipeline and the second front axle hydraulic control valve; A third hydraulically controlled one-way valve is arranged between the third pipeline and the hydraulic control valve of the rear axle. 3. The hydropneumatic suspension system with anti-roll function according to claim 2, further comprising: An increase and decrease control valve is arranged at the oil inlet of the hydraulic pump. 4. The hydropneumatic suspension system with anti-roll function according to claim 3, characterized in that, The first front axle hydraulic control valve, the second front axle hydraulic control valve and the rear axle hydraulic control valve are all three-position four-way electromagnetic reversing valves. 5. The hydropneumatic suspension system with anti-roll function according to claim 4, further comprising: a suspension connecting plate, which is arranged on the suspension; Four vehicle body height sensors are respectively arranged at the four corners of the vehicle body, one end of which is connected to the vehicle frame, and the other end is connected to the suspension connecting plate. 6. The hydropneumatic suspension system with anti-roll function according to claim 5, characterized in that, The increase and decrease control valve is a two-position three-way electromagnetic reversing valve, one end of which communicates with the oil outlet of the fuel tank and the oil inlet of the hydraulic pump, and the other end communicates with the hydraulic control valve. 7. The hydropneumatic suspension system with anti-roll function according to claim 6, further comprising: An overflow valve, one end of which communicates with the oil outlet of the fuel tank, and the other end communicates with the pressure increase and decrease control valve, and communicates with the hydraulic control valve. 8. The hydropneumatic suspension system with anti-roll function according to claim 1, characterized in that, The vehicle frame includes two longitudinal beams and two cross beams; Wherein, the beam is vertically arranged with the longitudinal beam; The oil-gas spring is fixedly connected with the longitudinal beam. 9. A method for controlling a hydropneumatic suspension system with an anti-roll function, characterized in that it comprises: When the vehicle body height sensor detects that the heights of the front and rear axles are inconsistent, adjust the hydraulic control valve at the corresponding position of the low-height axle and the oil flow of the corresponding oil and gas spring to meet: Among them, λ1 is the _first correction coefficient, h is the target height, Δh is the absolute value of the height difference between the front and rear axles, v is the vehicle speed during adjustment, V is the volume of the oil-pneumatic spring, and a is the oil in the corresponding oil-pneumatic spring Height, S is the distance between the frame and the axle, _Q0 is the rated oil flow of the hydraulic pump.