Four-quadrant oil pump system and control method thereof

Abstract

The invention belongs to a four-quadrant oil pump system in the technical field of hydraulic active suspensions, and further relates to a control method of the four-quadrant oil pump system. An upper actuator cavity (1-1) of the actuator (1) is communicated with the positive displacement pump (5) through a first pipeline (1-3), a lower actuator cavity (1-2) of the actuator (1) is communicated with the positive displacement pump (5) through a second pipeline (1-4), a first on-off valve (2-1) and a first energy accumulator (3-1) are arranged on the first pipeline (1-3), the positive displacement pump (5) is connected with a motor (7) through a third pipeline (1-5), the positive displacement pump (5) is connected with the motor (7), and a controller (8) is connected with a power source (9) and a domain controller (10). According to the four-quadrant oil pump system, flexible work switching under the active lifting working condition, the active descending working condition, the passive lifting working condition and the passive descending working condition can be achieved, kinetic energy generated in a hydraulic system in the running process is converted into electric energy, and the cruising ability of a vehicle and the use efficiency of a power source are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydraulic active suspension, and more specifically, relates to a four-quadrant oil pump system. The present invention also relates to a control method of the four-quadrant oil pump system. Background Art

[0002] There are many types of hydraulic active suspensions in the prior art. The electric oil pump in the hydraulic active suspension provides high-pressure hydraulic oil to the suspension system so that the suspension system can operate normally. The electric oil pump integrates a motor controller, a motor, and a positive displacement pump assembly. During use, the motor controller receives external signals, processes the external signals, and finally inputs voltage and current signals to the motor. The motor converts electrical energy into kinetic energy, so that the motor drives the positive displacement pump assembly to move and drives the hydraulic oil to flow.

[0003] Since the suspension system needs to provide a large lifting force during operation, the electric oil pump also needs to overcome a large hydraulic pressure; and the suspension system also has high requirements for operating speed, so the electric oil pump also needs to output a large flow rate. Due to the high pressure and large flow environment, the operating power of existing electric oil pumps is relatively large, with a rated power of more than 3kW and a peak power of more than 6kW.

[0004] During the driving process, due to unstable road conditions, the suspension system needs to operate frequently to adjust the vehicle body state. Since the electric oil pump has a large power, it consumes a lot of electricity, which will greatly reduce the vehicle's endurance.

[0005] In the prior art, there is a technology named "A pump-controlled hydraulic system and method for wave compensation" and the publication (announcement) number is "CN116517896A", which relates to a pump-controlled hydraulic system and method for wave compensation. The system includes a power module, a flow asymmetric compensation module, an oil replenishment module, a safety overflow module, a pressure temperature detection module, an actuator module and a hydraulic valve block for connecting various components. The power module, the pressure temperature detection module and a part of the oil replenishment module are connected to the upper side of the hydraulic valve block, the safety overflow module is connected to the right and front side of the hydraulic valve block, the flow asymmetric compensation module is connected to the left and right sides of the hydraulic valve block, and the pressure temperature detection module is connected to the front side of the hydraulic valve block. The present invention proposes a wave compensation control method, which combines the four quadrants of the pump control system with the wave motion to analyze the corresponding working conditions, uses the pump-controlled hydraulic system to perform displacement compensation and effective use of energy under the corresponding working conditions, effectively combines the four quadrants of the pump control system with the common DC bus technology, and realizes the energy management of the pump control system and the high-performance control of the hydraulic system.

[0006] However, this technology does not involve the technical problems and technical solutions of the present application. Summary of the invention

[0007] The technical problem to be solved by the present invention is: in view of the deficiencies in the prior art, a four-quadrant oil pump system is provided to make up for the shortcomings of the electric oil pump in the prior art, which can realize the switching of active lifting condition, active lowering condition, passive lifting condition and passive lowering condition, and convert the kinetic energy generated in the hydraulic system during operation into electrical energy, which is recovered and stored in the power supply of the whole vehicle, thereby improving the vehicle's endurance and power utilization efficiency, and improving the overall performance.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is:

[0009] The present invention is a four-quadrant oil pump system, wherein the actuator upper chamber of the actuator is connected to the displacement pump through a first pipeline, the actuator lower chamber of the actuator is connected to the displacement pump through a second pipeline, a first opening and closing valve and a first accumulator are arranged on the first pipeline, a second opening and closing valve and a second accumulator are arranged on the second pipeline, the displacement pump is connected to a motor through a third pipeline, a throttle is arranged on the third pipeline, the displacement pump is connected to the motor, the motor is connected to a controller, the controller is connected to a power supply and a domain controller, the controller is connected to a sensor, the sensor is connected to the motor, the sensor, the displacement pump, the one-way valve, the motor, the controller, and the throttle are integrated together to form an electric oil pump.

[0010] The controller is connected to a first sensor and a second sensor. The first sensor is connected to the motor and the displacement pump through a fourth pipeline. The second sensor is connected to the motor and the displacement pump through a fifth pipeline. The first sensor and the second sensor are respectively integrated with a pressure sensor and a temperature sensor.

[0011] The actuator integrates a shock absorber and a spring, and the actuator connects the wheel and the vehicle body.

[0012] A first one-way valve is arranged on the fourth pipeline, and a second one-way valve is arranged on the fifth pipeline.

[0013] The motor can rotate forward or reverse, and can be used as an electric motor at the same time.

[0014] The four-quadrant oil pump system is configured as a structure capable of switching between active lifting working conditions, active lowering working conditions, passive lifting working conditions, and passive lowering working conditions.

[0015] When the motor drives the displacement pump to rotate forward, the upper part of the displacement pump is the oil suction port, the lower part of the displacement pump is the oil discharge port, the oil discharge port is finally connected to the actuator lower cavity of the actuator, and the oil suction port is finally connected to the actuator upper cavity of the actuator.

[0016] When the motor drives the displacement pump to rotate in the opposite direction, the upper part of the displacement pump is the oil discharge port, the lower part of the displacement pump is the oil suction port, the oil discharge port is finally connected to the actuator upper cavity of the actuator, and the oil suction port is finally connected to the actuator lower cavity of the actuator.

[0017] The present invention also relates to a control method for a four-quadrant oil pump system that can make up for the shortcomings of the electric oil pump in the prior art, can realize switching among active lifting conditions, active lowering conditions, passive lifting conditions, and passive lowering conditions, and convert the kinetic energy generated in the hydraulic system during operation into electrical energy, which is recovered and stored in the power supply of the entire vehicle, thereby improving the vehicle's endurance and power utilization efficiency and enhancing the overall performance.

[0018] The control steps of the control method of the four-quadrant oil pump system are as follows:

[0019] S1. When the four-quadrant oil pump system enters the active lifting condition, the domain controller sends a lifting command to the controller, and the controller transmits the electric energy of the power supply to the motor. The motor drives the displacement pump to rotate forward. At this time, the upper part of the displacement pump is the oil suction port, and the lower part of the displacement pump is the oil discharge port. The oil discharge port is finally connected to the lower cavity of the actuator, and the oil suction port is finally connected to the upper cavity of the actuator; a part of the oil flows into the motor through the throttle port to cool and lubricate the motor, and the oil in the motor flows back to the oil suction chamber of the displacement pump through the first one-way valve to replenish the displacement pump; the oil discharged by the displacement pump flows through the second accumulator and the second on-off valve, and then flows into the lower cavity of the actuator, the actuator extends, and the vehicle body is lifted; in this process, the motor performs work and consumes the electric energy of the power supply;

[0020] S2. When the four-quadrant oil pump system enters the active descent condition, the domain controller sends a descent command to the controller, and the controller transmits the electrical energy of the power supply to the motor. The motor drives the displacement pump to rotate in the opposite direction. At this time, the top of the displacement pump is the oil discharge port, and the bottom of the displacement pump is the oil suction port. The oil discharge port is finally connected to the upper cavity of the actuator, and the oil suction port is finally connected to the lower cavity of the actuator. A part of the oil flows into the motor through the throttle port to cool and lubricate the motor, and the oil in the motor flows back to the oil suction chamber of the displacement pump through the second one-way valve to replenish the displacement pump. The oil discharged by the displacement pump flows through the first accumulator and the first opening and closing valve, and then flows into the upper cavity of the actuator, the actuator shortens, and the vehicle body descends. In this process, the motor performs work and consumes electrical energy from the power supply.

[0021] When the four-quadrant oil pump system enters the passive descent condition, it is also equivalent to the condition in which the wheels are lifted. This condition occurs when the vehicle passes over a raised road surface. During passive descent, the domain controller does not send any instructions to the controller. Due to external pressure, the actuator is shortened, and the oil flows out of the lower cavity of the actuator and flows into the upper cavity of the actuator. When the oil flows through the displacement pump, it drives the displacement pump to rotate, and the displacement pump drives the motor to rotate. At this time, the motor is used as a generator, and the electrical energy generated during the rotation of the displacement pump is transmitted to the power supply through the controller for storage.

[0022] When the four-quadrant oil pump system enters the passive lifting condition, it is also equivalent to the condition in which the wheels are lowered. This condition occurs when the vehicle passes through a pothole road. During passive lifting, the domain controller does not send any instructions to the controller. Due to the external pressure, the actuator extends. At this time, the oil flows in from the lower cavity of the actuator and flows out from the upper cavity of the actuator. When the oil flows through the volume pump, it drives the volume pump to rotate, and the volume pump drives the motor to rotate. At this time, the motor is used as a generator, and the electrical energy generated during the rotation of the volume pump is transmitted to the power supply through the controller for storage.

[0023] The technical solution of the present invention is adopted, and the working principle and beneficial effects are as follows:

[0024] The four-quadrant oil pump system described in the present invention has a structure in which the actuator integrates a shock absorber and a spring, and the actuator is used to connect the wheel and the body. The on-off valve is used to control the direction, flow rate and pressure of the hydraulic oil entering the actuator. The accumulator is used to store energy for the hydraulic circuit and absorb the vibration generated in the hydraulic system. The sensor integrates a pressure sensor and a temperature sensor to collect the pressure and temperature of the hydraulic system. The displacement pump is connected to the motor through a mechanical structure. After the controller issues an instruction, the motor can rotate forward and reverse, thereby driving the displacement pump to rotate forward and reverse. When the displacement pump rotates, it can provide high-pressure oil for the hydraulic system. The controller and the motor are connected through a wire, and the controller controls the power supply to transmit electric energy to the motor. The motor can rotate forward or reverse. The motor can also be used as a motor or a generator. The power supply is arranged at the vehicle end to provide electric energy to the controller and also recover stored energy. The domain controller inputs a command signal to the controller. The sensor, the displacement pump, the one-way valve, the motor, the controller, and the throttle are integrated together and are called an electric oil pump. The electric oil pump used in the hydraulic active suspension in the prior art cannot realize four-quadrant operation and can only be used in active lifting and active lowering conditions. It can only consume the electric energy of the vehicle power supply and cannot realize energy recovery. The present invention can make up for the shortcomings of the existing electric oil pump, so that the electric oil pump can be used in active lifting and active lowering conditions, and can also operate in passive lifting and passive lowering conditions, and can convert the kinetic energy generated in the hydraulic system during operation into electrical energy, and recover and store it in the vehicle power storage power supply, thereby improving the vehicle's endurance and power efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The following is a brief description of the contents and symbols in the drawings of this specification:

[0026] Figure 1 It is a structural schematic diagram of the four-quadrant oil pump system of the present invention;

[0027] Figure 2 A schematic diagram of the four quadrants, pressure and flow of the four-quadrant oil pump system of the present invention;

[0028] Figure 3 It is a cross-sectional structural schematic diagram of the four-quadrant oil pump system of the present invention;

[0029] The marks in the attached drawings are: 1, actuator; 1-1, actuator upper chamber; 1-2, actuator lower chamber; 1-3, first pipeline; 1-4, second pipeline; 1-5, third pipeline; 1-6, fourth pipeline; 1-7, fifth pipeline; 2-1, first opening and closing valve; 2-2, second opening and closing valve; 3-1, first accumulator; 3-2, second accumulator; 4, sensor; 4-1, first sensor; 4-2, second sensor; 5, positive displacement pump; 6, one-way valve ;6-1, first one-way valve;6-2, second one-way valve;7, motor;8, controller;9, power supply;10, domain controller;11, throttle;12, controller cover;13, controller assembly;14, main housing;15, motor stator assembly;16, motor rotor assembly;17, intermediate housing assembly;18, manifold;19, bushing;20, sensor;21, crescent plate;22, positive displacement pump gear;23, positive displacement pump ring gear;24, pump cover. DETAILED DESCRIPTION

[0030] The following is a further detailed description of the specific implementation of the present invention, such as the shape, structure, mutual position and connection relationship between the various components involved, the function and working principle of each part, etc., through the description of the embodiments with reference to the accompanying drawings:

[0031] As attached Figure 1 -Attached Figure 3As shown, the present invention is a four-quadrant oil pump system, the actuator upper chamber 1-1 of the actuator 1 is connected to the displacement pump 5 through the first pipeline 1-3, the actuator lower chamber 1-2 of the actuator 1 is connected to the displacement pump 5 through the second pipeline 1-4, the first pipeline 1-3 is provided with a first opening and closing valve 2-1 and a first accumulator 3-1, the second pipeline 1-4 is provided with a second opening and closing valve 2-2 and a second accumulator 3-2, the displacement pump 5 is connected to the motor 7 through the third pipeline 1-5, the third pipeline 1-5 is provided with a throttle 11, the displacement pump 5 is connected to the motor 7, the motor 7 is connected to the controller 8, the controller 8 is connected to the power supply 9 and the domain controller 10, the controller 8 is connected to the sensor 4, the sensor is connected to the motor 7, the sensor 4, the displacement pump 5, the one-way valve 6, the motor 7, the controller 8, and the throttle 11 are integrated together to form an electric oil pump. The above structure proposes an improved technical solution for the deficiencies in the prior art. When the structure is set, the actuator 1 integrates the shock absorber and the spring, and the actuator 1 is used to connect the wheel and the body. The on-off valve is used to control the direction, flow rate and pressure of the hydraulic oil entering the actuator 1. The accumulator is used to store energy for the hydraulic circuit and absorb the vibration generated in the hydraulic system. The sensor 4 integrates the pressure sensor and the temperature sensor to collect the pressure and temperature of the hydraulic system. The displacement pump 5 is connected to the motor 7 through a mechanical structure. After the controller 8 issues an instruction, the motor 7 can rotate forward and reverse, thereby driving the displacement pump 5 to rotate forward and reverse. When the displacement pump 5 rotates, it can provide high-pressure oil for the hydraulic system. The controller 8 is connected to the motor 7 through a wire, and the controller 8 controls the power supply 9 to transmit electric energy to the motor 7. The motor 7 can rotate forward or reverse. The motor 7 can also be used as a motor or a generator. The power supply 9 is arranged at the vehicle end to provide power to the controller 8 and also recover energy storage. The domain controller 10 inputs a command signal to the controller 8. The sensor 4, the displacement pump 5, the one-way valve 6, the motor 7, the controller 8, and the throttle 11 are integrated together and are called an electric oil pump. The electric oil pump used in the hydraulic active suspension in the prior art cannot realize four-quadrant operation, can only be used in active lifting conditions and active lowering conditions, can only consume the electric energy of the vehicle power supply, and cannot realize energy recovery. The present invention can make up for the shortcomings of the existing electric oil pump, so that the electric oil pump can be used in active lifting conditions and active lowering conditions, and can also operate under passive lifting and passive lowering conditions, and can convert the kinetic energy generated in the hydraulic system during operation into electric energy, and recover and store it in the vehicle power supply, thereby improving the vehicle's endurance and power efficiency. The four-quadrant oil pump system described in the present invention can make up for the shortcomings of the electric oil pump in the prior art, can realize active lifting conditions, active lowering conditions, passive lifting conditions, and passive lowering conditions, and can switch flexibly, and convert the kinetic energy generated in the hydraulic system during operation into electric energy, and recover and store it in the vehicle power supply, thereby improving the vehicle's endurance and power efficiency, and improving overall performance.

[0032] The controller 8 is connected to the first sensor 4-1 and the second sensor 4-2. The first sensor 4-1 is connected to the motor 7 and the displacement pump 5 through the fourth pipeline 1-6. The second sensor 4-2 is connected to the motor 7 and the displacement pump 5 through the fifth pipeline 1-7. The first sensor 4-1 and the second sensor 4-2 are respectively integrated with a pressure sensor and a temperature sensor. In the above structure, the sensor 4 includes the first sensor 4-1 and the second sensor 4-2, and the two sensors are respectively used to collect pressure and temperature information of the hydraulic system, and feed back the collected information to the controller 8.

[0033] The actuator 1 integrates the shock absorber and the spring, and the actuator 1 connects the wheel and the vehicle body. In the above structure, the actuator 1 integrates the shock absorber and the spring, and when the upper chamber of the actuator and the lower chamber of the actuator are filled with oil respectively, the length of the actuator can be adjusted to achieve lifting and lowering of the vehicle body.

[0034] The fourth pipeline 1-6 is provided with a first one-way valve 6-1, and the fifth pipeline 1-7 is provided with a second one-way valve 6-2. With the above structure, the one-way valve 6 realizes one-way flow control. When in the active lifting condition, the oil in the motor 7 flows back to the oil suction chamber of the displacement pump 5 through the first one-way valve 6-1 to replenish the oil for the displacement pump 5; when in the active descending condition, the oil in the motor 7 flows back to the oil suction chamber of the displacement pump 5 through the second one-way valve 6-2 to replenish the oil for the displacement pump 5.

[0035] The motor 7 can rotate forward or reverse, and the motor 7 can also be used as an electric motor. In the above structure, when the passive lowering or passive lifting working condition is in progress, when the oil flows through the displacement pump 5, it will drive the displacement pump 5 to rotate, and the displacement pump 5 will drive the motor 7 to rotate. At this time, the motor 7 is used as a generator, and the generated electric energy is transmitted to the power supply 9 for storage during the rotation process.

[0036] The four-quadrant oil pump system is configured to be able to switch between active lifting conditions, active lowering conditions, passive lifting conditions, and passive lowering conditions. The four-quadrant oil pump system of the present invention enables the electric oil pump to be used in active lifting conditions and active lowering conditions, and can also operate in passive lifting and passive lowering conditions, and has four operating modes.

[0037] When the motor 7 drives the displacement pump 5 to rotate forward, the upper part of the displacement pump 5 is the oil suction port, the lower part of the displacement pump 5 is the oil discharge port, the oil discharge port is finally connected to the actuator lower chamber 1-2 of the actuator 1, and the oil suction port is finally connected to the actuator upper chamber 1-1 of the actuator 1. When the motor 7 drives the displacement pump 5 to rotate reversely, the upper part of the displacement pump 5 is the oil discharge port, the lower part of the displacement pump 5 is the oil suction port, the oil discharge port is finally connected to the actuator upper chamber 1-1 of the actuator 1, and the oil suction port is finally connected to the actuator lower chamber 1-2 of the actuator 1. The above structure can conveniently and reliably realize the control of lifting and lowering.

[0038] The present invention also relates to a control method for a four-quadrant oil pump system that can make up for the shortcomings of the electric oil pump in the prior art, can realize switching among active lifting conditions, active lowering conditions, passive lifting conditions, and passive lowering conditions, and convert the kinetic energy generated in the hydraulic system during operation into electrical energy, which is recovered and stored in the power supply of the entire vehicle, thereby improving the vehicle's endurance and power utilization efficiency and enhancing the overall performance.

[0039] The control steps of the control method of the four-quadrant oil pump system are as follows:

[0040] S1. When the four-quadrant oil pump system enters the active lifting condition, the domain controller 10 sends a lifting command to the controller 8, and the controller 8 transmits the electric energy of the power supply 9 to the motor 7. The motor 7 drives the displacement pump 5 to rotate forward. At this time, the upper part of the displacement pump 5 is the oil suction port, and the lower part of the displacement pump 5 is the oil discharge port. The oil discharge port is finally connected to the lower cavity of the actuator, and the oil suction port is finally connected to the upper cavity of the actuator; a part of the oil flows into the motor 7 through the throttle port 11 to cool and lubricate the motor 7, and the oil in the motor 7 flows back to the oil suction cavity of the displacement pump 5 through the first one-way valve 6-1 to replenish the displacement pump 5; the oil discharged by the displacement pump 5 flows through the second accumulator 3-2 and the second opening and closing valve 2-2, and then flows into the lower cavity 1-2 of the actuator, the actuator 1 extends, and the vehicle body is lifted; in this process, the motor 7 does work and consumes the electric energy of the power supply 9. ; S2. When the four-quadrant oil pump system enters the active descending condition, the domain controller 10 sends a descending command to the controller 8, and the controller 8 transmits the electric energy of the power supply 9 to the motor 7. The motor 7 drives the displacement pump 5 to rotate in the opposite direction. At this time, the upper part of the displacement pump 5 is the oil discharge port, and the lower part of the displacement pump 5 is the oil suction port. The oil discharge port is finally connected to the upper cavity of the actuator, and the oil suction port is finally connected to the lower cavity of the actuator; a part of the oil flows into the motor 7 through the throttle port 11 to cool and lubricate the motor 7, and the oil in the motor 7 flows back to the oil suction cavity of the displacement pump 5 through the second one-way valve 6-2 to replenish the displacement pump 5; the oil discharged by the displacement pump 5 flows through the first accumulator 3-1 and the first opening and closing valve 2-1, and then flows into the upper cavity 1-1 of the actuator, the actuator 1 is shortened, and the vehicle body descends; in this process, the motor 7 performs work and consumes the electric energy of the power supply.

[0041] When the four-quadrant oil pump system enters the passive descent condition, it is also equivalent to the condition in which the wheels are lifted. This condition occurs when the vehicle passes over a raised road surface. During passive descent, the domain controller 10 does not send any instructions to the controller 8. Due to the external pressure, the actuator 1 is shortened, and the oil flows out of the lower chamber 1-2 of the actuator and flows into the upper chamber 1-1 of the actuator. When the oil flows through the displacement pump 5, it drives the displacement pump 5 to rotate, and the displacement pump 5 drives the motor 7 to rotate. At this time, the motor 7 is used as a generator, and the electric energy generated during the rotation of the displacement pump 5 is transmitted to the power supply 9 through the controller 8 for storage.

[0042] When the four-quadrant oil pump system enters the passive lifting condition, it is also equivalent to the condition in which the wheels are lowered. This condition will occur when the vehicle passes through a pothole road. During passive lifting, the domain controller 10 does not send any instructions to the controller 8. Due to the external pressure, the actuator 1 is extended. At this time, the oil flows in from the lower chamber 1-2 of the actuator, and the oil flows out from the upper chamber 1-1 of the actuator. When flowing through the displacement pump 5, it will drive the displacement pump 5 to rotate, and the displacement pump 5 drives the motor 7 to rotate. At this time, the motor 7 is used as a generator, and the electric energy generated during the rotation of the displacement pump 5 is transmitted to the power supply 9 through the controller 8 for storage.

[0043] In the system described in the present invention, one controller cover plate 12 is provided; one controller assembly 13 is provided; one main housing 14 is provided; two motor stator assemblies 15 are provided; two motor rotor assemblies 16 are provided; two intermediate housings 17 are provided; four manifolds 18 are provided; two bushings 19 are provided; four sensors 20 are provided; two crescent plates 21 are provided; two gears of the displacement pump 22 are provided; two displacement pump gear rings 23 are provided; and two pump covers 24 are provided.

[0044] The four-quadrant oil pump system described in the present invention has a structure in which the actuator 1 integrates a shock absorber and a spring, and the actuator 1 is used to connect the wheel and the body. The on-off valve is used to control the direction, flow rate, and pressure of the hydraulic oil entering the actuator 1. The accumulator is used to store energy for the hydraulic circuit and absorb the vibration generated in the hydraulic system. The sensor 4 integrates a pressure sensor and a temperature sensor to collect the pressure and temperature of the hydraulic system. The displacement pump 5 is connected to the motor 7 through a mechanical structure. After the controller 8 issues an instruction, the motor 7 can rotate forward and reverse, thereby driving the displacement pump 5 to rotate forward and reverse. When the displacement pump 5 rotates, it can provide high-pressure oil for the hydraulic system. The controller 8 is connected to the motor 7 through a wire, and the controller 8 controls the power supply 9 to transmit electric energy to the motor 7. The motor 7 can rotate forward or reverse. The motor 7 can also be used as a motor or a generator. The power supply 9 is arranged at the vehicle end to provide electric energy to the controller 8 and also to recover stored energy. The domain controller 10 inputs a command signal to the controller 8. The sensor 4, the displacement pump 5, the one-way valve 6, the motor 7, the controller 8, and the throttle 11 are integrated together and are called an electric oil pump. The electric oil pump used in the hydraulic active suspension in the prior art cannot realize four-quadrant operation and can only be used in active lifting conditions and active lowering conditions. It can only consume the electric energy of the vehicle power supply and cannot realize energy recovery. The present invention can make up for the shortcomings of the existing electric oil pump, so that the electric oil pump can be used in active lifting conditions and active lowering conditions, and can also operate under passive lifting and passive lowering conditions, and can convert the kinetic energy generated in the hydraulic system during operation into electrical energy, and recover and store it in the vehicle power storage power supply, thereby improving the vehicle's endurance and power efficiency.

[0045] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A four-quadrant oil pump system, characterized in that: The actuator upper chamber (1-1) of the actuator (1) is connected to the displacement pump (5) through a first pipeline (1-3), the actuator lower chamber (1-2) of the actuator (1) is connected to the displacement pump (5) through a second pipeline (1-4), a first opening and closing valve (2-1) and a first accumulator (3-1) are arranged on the first pipeline (1-3), a second opening and closing valve (2-2) and a second accumulator (3-2) are arranged on the second pipeline (1-4), and the displacement pump (5) is connected to the displacement pump (5) through a third pipeline (1-5). The motor (7) is connected, a throttle (11) is arranged on the third pipeline (1-5), the displacement pump (5) is connected to the motor (7), the motor (7) is connected to the controller (8), the controller (8) is connected to the power supply (9) and the domain controller (10), the controller (8) is connected to the sensor (4), the sensor is connected to the motor (7), the sensor (4), the displacement pump (5), the one-way valve (6), the motor (7), the controller (8), and the throttle (11) are integrated together to form an electric oil pump.

2. The four-quadrant oil pump system according to claim 1, characterized in that: The controller (8) is connected to a first sensor (4-1) and a second sensor (4-2); the first sensor (4-1) is connected to a motor (7) and a displacement pump (5) via a fourth pipeline (1-6); the second sensor (4-2) is connected to a motor (7) and a displacement pump (5) via a fifth pipeline (1-7); and the first sensor (4-1) and the second sensor (4-2) are respectively integrated with a pressure sensor and a temperature sensor.

3. The four-quadrant oil pump system according to claim 2, characterized in that: The actuator (1) integrates a shock absorber and a spring, and the actuator (1) is connected to the wheel and the vehicle body; a first one-way valve (6-1) is arranged on the fourth pipeline (1-6), and a second one-way valve (6-2) is arranged on the fifth pipeline (1-7).

4. The four-quadrant oil pump system according to claim 1 or 2, characterized in that: The motor (7) can rotate forward or reverse, and the motor (7) can also be used as an electric motor.

5. The four-quadrant oil pump system according to claim 4, characterized in that: The four-quadrant oil pump system is configured as a structure capable of switching between active lifting working conditions, active lowering working conditions, passive lifting working conditions, and passive lowering working conditions.

6. The four-quadrant oil pump system according to claim 5, characterized in that: When the motor (7) drives the displacement pump (5) to rotate in the forward direction, the upper part of the displacement pump (5) is an oil suction port, and the lower part of the displacement pump (5) is an oil discharge port. The oil discharge port is ultimately connected to the actuator lower chamber (1-2) of the actuator (1), and the oil suction port is ultimately connected to the actuator upper chamber (1-1) of the actuator (1).

7. The four-quadrant oil pump system according to claim 5, characterized in that: When the motor (7) drives the displacement pump (5) to rotate in the reverse direction, the upper part of the displacement pump (5) is an oil discharge port, and the lower part of the displacement pump (5) is an oil suction port. The oil discharge port is ultimately connected to the actuator upper chamber (1-1) of the actuator (1), and the oil suction port is ultimately connected to the actuator lower chamber (1-2) of the actuator (1).

8. A control method for a four-quadrant oil pump system, characterized in that: The control steps of the control method of the four-quadrant oil pump system are as follows: S1. When the four-quadrant oil pump system enters the active lifting condition, the domain controller (10) sends a lifting command to the controller (8), and the controller (8) transmits the electric energy of the power supply (9) to the motor (7), and the motor (7) drives the displacement pump (5) to rotate in the forward direction. At this time, the upper part of the displacement pump (5) is the oil suction port, and the lower part of the displacement pump (5) is the oil discharge port. The oil discharge port is finally connected to the lower chamber of the actuator, and the oil suction port is finally connected to the upper chamber of the actuator; a part of the oil passes through the throttle port (11 ) flows into the motor (7) to cool and lubricate the motor (7), and the oil in the motor (7) flows back to the oil suction chamber of the displacement pump (5) through the first non-return valve (6-1) to replenish the displacement pump (5); the oil discharged by the displacement pump (5) flows through the second accumulator (3-2) and the second opening and closing valve (2-2), and then flows into the actuator lower chamber (1-2), the actuator (1) extends, and the vehicle body is lifted; in this process, the motor (7) performs work and consumes the electric energy of the power supply (9); S2. When the four-quadrant oil pump system enters the active descending condition, the domain controller (10) sends a descending instruction to the controller (8), and the controller (8) transmits the electric energy of the power supply (9) to the motor (7), and the motor (7) drives the displacement pump (5) to rotate in the opposite direction. At this time, the upper part of the displacement pump (5) is the oil discharge port, and the lower part of the displacement pump (5) is the oil suction port. The oil discharge port is finally connected to the upper cavity of the actuator, and the oil suction port is finally connected to the lower cavity of the actuator; a part of the oil flows into the motor (7) through the throttle port (11) to cool and lubricate the motor (7), and the oil in the motor (7) flows back to the oil suction chamber of the displacement pump (5) through the second one-way valve (6-2) to replenish the oil for the displacement pump (5); the oil discharged by the displacement pump (5) flows through the first accumulator (3-1) and the first opening and closing valve (2-1), and then flows into the upper cavity (1-1) of the actuator, the actuator (1) is shortened, and the vehicle body descends; in this process, the motor (7) performs work and consumes the electric energy of the power supply.

9. The control method of the four-quadrant oil pump system according to claim 8, characterized in that: When the four-quadrant oil pump system enters the passive descent condition, it is also equivalent to the condition in which the wheels are lifted. This condition occurs when the vehicle passes over a raised road surface. During passive descent, the domain controller (10) does not send any instructions to the controller (8). Due to the external pressure, the actuator (1) is shortened, and the oil flows out of the actuator lower chamber (1-2) and flows into the actuator upper chamber (1-1). When the oil flows through the displacement pump (5), it drives the displacement pump (5) to rotate, and the displacement pump (5) drives the motor (7) to rotate. At this time, the motor (7) is used as a generator. During the rotation of the displacement pump (5), the generated electric energy is transmitted to the power supply (9) through the controller (8) for storage.

10. The control method of the four-quadrant oil pump system according to claim 8, characterized in that: When the four-quadrant oil pump system enters the passive lifting condition, it is also equivalent to the condition in which the wheels are lowered. This condition occurs when the vehicle passes through a pothole road. During passive lifting, the domain controller (10) does not send any instructions to the controller (8). Due to the external pressure, the actuator (1) is extended. At this time, oil flows into the actuator lower chamber (1-2) and flows out of the actuator upper chamber (1-1). When the oil flows through the displacement pump (5), it drives the displacement pump (5) to rotate, and the displacement pump (5) drives the motor (7) to rotate. At this time, the motor (7) is used as a generator. During the rotation of the displacement pump (5), the generated electric energy is transmitted to the power supply (9) through the controller (8) for storage.

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