Excavator boom potential energy recovery system based on oil-electric hybrid
By adopting a hybrid potential energy recovery system on the excavator boom, the problems of potential energy waste and hydraulic shock in traditional hydraulic systems are solved, and efficient energy recovery and protection of system components are achieved.
Patent Information
- Application Number
- CN202510351986.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2025-06-06
AI Technical Summary
The traditional excavator hydraulic system will cause waste of potential energy when the boom descends, and hydraulic shock will occur when the boom is frequently operated, damage the system components and affect the service life.
The potential energy recovery system of the excavator boom arm is adopted based on a hybrid oil-electrical excavator boom. Through the cooperation of the hydraulic pump/motor and motor, the potential energy is converted into electrical energy when the boom descends and stored. The hydraulic shock is buffered using components such as accumulators and proportional flow control valves to reduce energy loss.
It improves the recovery efficiency of potential energy of the excavator boom, reduces the damage to system components by hydraulic shock, extends the service life, and reduces carbon emissions and environmental pollution.
Smart Images
Figure CN120100780A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of engineering hydraulic control, and in particular is a potential energy recovery system for an excavator boom based on an oil-electric hybrid. Background Art
[0002] In the process of working, the boom of a traditional excavator will release a large amount of potential energy when it is lowered. The gravitational potential energy wasted in the process of lowering the boom of the excavator is about 15% of the output energy of the hydraulic pump. This is because the traditional excavator hydraulic system has energy losses such as throttling loss and overflow loss at the inlet and outlet of the multi-way valve. These energies are usually dissipated in the form of heat or other forms of loss. Therefore, fully recovering the gravitational potential energy plays an important role in improving the energy efficiency of the hydraulic system of the excavator. The boom potential energy recovery system can store the potential energy released when the boom is lowered through a series of mechanical structures and electronic control systems, and convert it into electrical energy and hydraulic energy for storage, thereby realizing the reuse of energy. Excavators using the new boom potential energy recovery system can achieve efficient use of energy, reduce dependence on traditional energy, and also reduce carbon emissions and environmental pollution, which is in line with the concept of sustainable development. The research and development and application of this technology will have a positive impact on the excavator industry and promote the development of the construction machinery field in a more environmentally friendly and intelligent direction. Summary of the invention
[0003] In order to solve the problem of energy recovery and low-carbon environmental protection during the work of an excavator, the present invention invents a potential energy recovery system for an excavator boom based on an oil-electric hybrid.
[0004] The present invention adopts the following technical scheme: a potential energy recovery system for an excavator boom based on an oil-electric hybrid, comprising: a control module connected to a hydraulic cylinder, a rod chamber control module II connected to a rod chamber of a hydraulic cylinder and a rodless chamber control module I connected to a rodless chamber of a hydraulic cylinder, the control module components specifically comprising: a motor, a hydraulic pump / motor, an accumulator, an electric switch valve, a driver, a bidirectional DC-DC, a super capacitor, a controller, and a pressure sensor; the rodless chamber control module I or the rod chamber control module II comprises: a motor driving a hydraulic pump / motor, an oil outlet of the hydraulic pump / motor being connected to the rodless chamber of the hydraulic cylinder, an oil inlet of the hydraulic pump / motor sucking oil, an inlet and outlet of the hydraulic pump / motor The circuit between the ports is provided with electric switch valves in parallel, the hydraulic pump / motor outlet is connected to a pressure sensor and a hydraulic cylinder, the hydraulic pump / motor outlet is connected to the circuit of the hydraulic cylinder and an electric switch valve is set outside and connected to its inlet, the outlet of the electric switch valve is connected to the accumulator, the rodless cavity control module I and the rod cavity control module II share an accumulator, the driver is provided with a bidirectional DC-DC, and is respectively connected to a supercapacitor and a driver, the rodless cavity control module I and the rod cavity control module II of the hydraulic cylinder are connected and controlled by the same controller, the controller is respectively connected to the driver and the bidirectional DC-DC in the control module, and the controller is respectively connected to the electric switch valve and the pressure sensor of the two control modules.
[0005] Furthermore, the electric switch valve is a proportional flow control valve or a proportional reversing valve.
[0006] Furthermore, a proportional flow control valve is arranged in parallel in the circuit between the inlet and outlet of the hydraulic pump / motor, and a second proportional flow control valve is arranged outside the circuit of the hydraulic pump / motor outlet connected to the hydraulic cylinder and connected to its inlet.
[0007] Furthermore, a springless check valve and a spring check valve are arranged on the oil circuit connecting the oil inlet of the hydraulic pump / motor and the oil suction, the inlet of the springless check valve is connected to the oil suction, and the outlet of the spring check valve is connected to the oil suction, and a springless check valve is arranged in parallel in the circuit between the inlet and outlet of the hydraulic pump / motor, and the outlet of the springless check valve is connected to the inlet of the spring check valve.
[0008] Furthermore, a second one-way valve is included, the outlet of the second proportional flow control valve is connected to the inlet of the second one-way valve, and the outlet of the second one-way valve is connected to the oil port of the hydraulic cylinder.
[0009] Furthermore, the second one-way valve has zero opening pressure.
[0010] Furthermore, the hydraulic pump / motor outlet is also connected to a relief valve, and the relief valve outlet is connected to an oil tank.
[0011] The use of motors as the power source of excavators provides convenient conditions for the application of electrical energy recovery and utilization methods. The electrical recovery method converts the gravitational potential energy of the working device into electrical energy for storage through a hydraulic motor or a hydraulic pump / motor-generator. In view of the shortcomings of the existing electric excavator using a multi-way valve control system, such as low energy efficiency, large battery installed capacity and short battery life, the present invention combines accumulators with electrical energy recovery to propose a new type of excavator boom potential energy recovery and reuse system. According to the area ratio of the two chambers of the boom hydraulic cylinder, the displacement of two hydraulic pumps / motors is configured to achieve flow matching and no throttling loss of the boom hydraulic cylinder. When the excavator boom is lowered, the oil in the rodless chamber of the hydraulic cylinder is discharged to the hydraulic pump / motor, and the hydraulic pump / motor discharges oil to the rod chamber of the hydraulic cylinder, pushing the hydraulic cylinder piston to retract. The oil in the rodless chamber of the hydraulic cylinder pushes the hydraulic pump / motor to rotate, and then drives the motor to rotate. At this time, the motor becomes a generator, generating electricity to generate electricity and storing it in a supercapacitor. However, when the hydraulic cylinder of the excavator boom moves frequently, a large hydraulic shock will be generated, which will damage the components in the system and affect the service life. Although the hydraulic shock pressure will overflow through the overflow valve at this time, the valve plays a role in protecting against overload, but it will cause energy loss and convert pressure energy into heat energy. The present invention combines an accumulator with electrical recovery of boom gravity potential energy to propose an oil-electric hybrid recovery of boom gravity potential energy to improve energy recovery efficiency and utilization. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 It is the hydraulic principle diagram of the present invention.
[0013] Among them, 1. Motor, 2. Hydraulic pump / motor, 3. Accumulator, 4. Springless check valve, 5. Spring check valve, 601. Proportional flow control valve, 602. Second proportional flow control valve, 7. Overflow valve, 8. Hydraulic cylinder, 9. Driver, 10. Bidirectional DC-DC, 11. Supercapacitor, 12. Controller, 13. Oil tank, 14. Pressure sensor, 15. Second check valve. DETAILED DESCRIPTION
[0014] As shown in FIG1 , a potential energy recovery system for an excavator boom based on an oil-electric hybrid type includes: a rod chamber control module II connected to the rod chamber of a hydraulic cylinder 8 and a rodless chamber control module I connected to the rodless chamber of the hydraulic cylinder 8, wherein the control module components specifically include: a motor 1, a hydraulic pump / motor 2, an accumulator 3, a springless check valve 4, a spring check valve 5, a proportional flow control valve 601, a second proportional flow control valve 602, a relief valve 7, a driver 9, a bidirectional DC-DC 10, a super capacitor 11, a controller 12, an oil tank 13, a pressure sensor 14, and a second check valve 15; wherein the rodless chamber control module I includes: the motor 1 drives the hydraulic pump / motor 2, the oil outlet of the hydraulic pump / motor 2 is connected to the rodless chamber of the hydraulic cylinder 8, the oil inlet of the hydraulic pump / motor is connected to the oil tank 13, and the oil circuit connecting the oil inlet of the hydraulic pump / motor to the oil tank 13 is provided with a springless check valve 4 and a spring check valve 5, the inlet of the springless check valve 4 is connected to the oil tank 13, and the spring check valve 5 is connected to the oil tank 13. The outlet of the check valve 5 is connected to the oil tank 13, and the circuit between the inlet and outlet of the hydraulic pump / motor is provided with a springless check valve 4 and a proportional flow control valve 601 in parallel. The outlet of the springless check valve 4 is connected to the inlet of the spring check valve 5. The springless check valve 4 and the second check valve 15 have zero opening pressure, and the spring check valve 5 has an opening pressure. The outlet of the hydraulic pump / motor 2 is respectively connected to the pressure sensor 14, the relief valve 7, the second check valve 15, and the second proportional flow control valve 602. The outlet of the relief valve 7 is connected to the oil tank 13, and the outlet of the hydraulic pump / motor 2 is connected to the inlet of the second proportional flow control valve 602. The outlet of the second proportional flow control valve 602 is connected to the accumulator 3 and the inlet of the second check valve 15. The difference between the rod chamber control module II and the rodless chamber control module is that the outlet of the second proportional flow control valve 602 of the rod chamber control module II is also connected to the accumulator 3, and the two second check valves 15 in the rod chamber control module II and the rodless chamber control module are connected.
[0015] A bidirectional DC-DC is provided for the driver 9, and is respectively connected to a supercapacitor 11 and the driver 9, and is connected to the rod chamber and rodless chamber control modules I of the hydraulic cylinder 8, which are respectively connected and controlled by the same controller 12. The controller 12 is respectively connected to the driver 9 and the bidirectional DC-DC 10 in the control module, and the controller 12 respectively controls the proportional flow control valve 601, the second proportional flow control valve 602, and the pressure sensor 14 of the two control modules.
[0016] The one-way valve 4 has zero opening pressure, and the spring one-way valve 5 has an opening pressure.
[0017] When the hydraulic shock is generated by the lowering of the boom, the proportional flow control valve can be opened, and the oil enters the accumulator 3 to absorb the hydraulic shock. The oil buffered by the accumulator 3 is released to the rod chamber of the hydraulic cylinder 8, reducing the input flow of the hydraulic pump / motor 2 of the rod chamber control module II, reducing the driving power of the motor connected thereto, and avoiding the loss of hydraulic energy; when the hydraulic shock is generated by the rapid rising of the boom, the proportional flow control valve 602 of the rod chamber control module II is opened, and the oil enters the accumulator 3 to absorb the hydraulic shock. The oil buffered by the accumulator 3 is released to the rodless chamber of the hydraulic cylinder 8, reducing the input flow of the hydraulic pump / motor 2 of the rodless chamber control module I, reducing the driving power of the motor connected thereto, and avoiding the loss of hydraulic energy.
[0018] Energy recovery process Working process: 1. Rapid arm movement, A. Rapid boom rise: During the rapid lifting of the boom, the motor 1 of the rodless chamber control module I drives the hydraulic pump / motor 2, and the hydraulic oil of the hydraulic pump / motor 2 quickly enters the rodless chamber of the hydraulic cylinder 8, and the oil in the rod chamber of the hydraulic cylinder (8) enters the hydraulic pump / motor 2 of the rod chamber control module II; when the hydraulic cylinder is under light load, both chambers of the hydraulic cylinder 8 will generate impact energy, and the rodless chamber will generate greater hydraulic impact energy due to the large amount of oil. In this process, the proportional flow control valve 602 is opened, and the oil in the rodless chamber enters the accumulator 3. The oil after buffering and releasing the impact energy enters the rod chamber of the hydraulic cylinder through the second one-way valve 15 of the rod chamber control module II to replenish the oil. After the hydraulic cylinder runs smoothly, the proportional flow control valve 602 is closed. The hydraulic oil drives the hydraulic pump / motor 2 of the rod chamber control module II to rotate, and drives the motor 1 to generate electricity, which is stored in the supercapacitor 11. When the boom is running smoothly, the proportional flow control valve 601 of the rod chamber control module II is powered on and opened. At this time, the pressure difference between the inlet and outlet of the hydraulic pump / motor 2 of the rod chamber control module II is basically zero, and the oil will return to the oil tank 13 through the spring-loaded check valve 5 of the rod chamber control module II. At this time, the motor 1 does not generate electricity, but the driving power of the motor 1 will be reduced.
[0019] B. Rapid descent of the boom During the rapid descent of the boom, when the motor 1 of the rod chamber control module II does not work, the hydraulic oil of the hydraulic pump / motor 2 connected thereto quickly enters the rod chamber of the hydraulic cylinder 8. The oil discharge volume of the hydraulic pump / motor 2 does not reach the required flow rate, which is easy to cause air suction. The oil of the accumulator 3 enters the rod chamber of the hydraulic cylinder 8 through the second one-way valve 15 of the rod chamber control module II for fluid replenishment. When the oil of the accumulator 3 is released, if the oil is still insufficient, the oil will be replenished twice through the two one-way valves 4 of the rod chamber control module II. This is because the resistance of the oil when passing through the two one-way valves 4 is much smaller than that of the hydraulic pump / motor 2. At this time, the two one-way valves 4 will open, and the oil will enter the rod chamber of the hydraulic cylinder 8 to avoid air suction. Since there is more oil in the rodless chamber of the hydraulic cylinder 8, it will generate a large hydraulic impact energy. If the proportional flow control valve 602 is not opened, the oil will affect the sealing effect and service life of the components. At this time, the proportional flow control valve 602 is opened, and the oil with hydraulic impact energy enters the accumulator 3. When the system releases the impact oil, the proportional flow control valve 602 is closed. The oil in the accumulator 3 will enter the low-pressure chamber of the hydraulic cylinder 8 through the two second one-way valves 15, reducing the flow of the hydraulic pump / motor 2 of the rod chamber control module II, reducing the power of driving the hydraulic pump / motor 2, and then the rodless chamber oil drives the hydraulic pump / motor 2 of the rodless chamber control module I to rotate, and drives the motor 1 connected thereto to generate electricity. The converted electrical energy is stored in the supercapacitor 11, and is used to drive the hydraulic pump / motor 2 when the boom is lifted.
[0020] 2. Smooth arm movement, A. Boom lowering: When the boom is lightly loaded and steadily lowered, the proportional flow control valves 601 and 602 of the two control modules are not opened. When the motor 1 of the rod chamber control module II is not working, the hydraulic cylinder 8 can be regarded as a single-piston pump due to the gravitational potential energy of the load. The oil in the rod chamber of the hydraulic cylinder 8 enters the rod chamber of the hydraulic cylinder 8 through the two one-way valves 4 of the rod chamber control module II; the oil in the rodless chamber of the hydraulic cylinder 8 is discharged through the hydraulic pump / motor 2 of the rodless chamber control module I and drives the motor 1 to rotate and generate electricity. At this time, the gravitational potential energy of the boom is converted into electrical energy for storage.
[0021] When the boom is overloaded, the proportional flow control valve 601 and the proportional flow control valve 602 of the two control modules are not opened. Due to the gravitational potential energy of the load, the hydraulic cylinder 8 can be regarded as a single-piston pump, and the motor 1 of the rod chamber control module II is started to work. If the oil is insufficient, the oil in the rod chamber of the hydraulic cylinder 8 enters the rod chamber of the hydraulic cylinder 8 through the two one-way valves 4 of the rod chamber control module II for oil replenishment, thereby reducing the driving power of the motor 1.
[0022] B. Boom rise During the stable lifting of the boom, the speed of the hydraulic cylinder 8 will be greatly reduced due to the heavy load. In the traditional excavator hydraulic system, the overflow safety valve will produce overflow loss, converting hydraulic energy into heat energy. Figure 1 In the system shown, the rotation speed of the motor 1 of the rodless cavity control module I is adjusted to match the system flow and reduce the overflow loss. At this time, the proportional flow control valve 601 of the rod cavity control module II is powered on and opened, reducing the pressure difference between the inlet and outlet of the hydraulic pump / motor 2 of the rod cavity control module II, and the proportional flow control valve 601, proportional flow control valve 602 of the rodless cavity control module I and the proportional flow control valve 601 of the rod cavity control module II are closed, and the rod cavity oil of the hydraulic cylinder 8 flows into the oil tank through the proportional flow control valve 601 of the rod cavity control module II and the one-way valve 5, reducing the pressure of the rod cavity of the hydraulic cylinder 8, thereby achieving the purpose of reducing the driving power of the motor 1, that is, reducing the electric energy required for the motor 1 to drive the hydraulic pump / motor.
Claims
1. A potential energy recovery system for an excavator boom based on an oil-electric hybrid, comprising: A control module connected to a hydraulic cylinder (8), characterized in that: a rod chamber control module II connected to the rod chamber of the hydraulic cylinder (8) and a rodless chamber control module I connected to the rodless chamber of the hydraulic cylinder (8), the control module components specifically comprising: a motor (1), a hydraulic pump / motor (2), an accumulator (3), an electric switch valve, a driver (9), a bidirectional DC-DC (10), a super capacitor (11), a controller (12), and a pressure sensor (14); the rodless chamber control module I or the rod chamber control module II comprises: the motor (1) drives the hydraulic pump / motor (2), the oil outlet of the hydraulic pump / motor (2) is connected to the rodless chamber of the hydraulic cylinder (8), the oil inlet of the hydraulic pump / motor sucks oil, the circuit between the inlet and outlet of the hydraulic pump / motor is provided with an electric switch valve in parallel, the hydraulic pump / motor The outlet of the motor (2) is connected to a pressure sensor (14) and a hydraulic cylinder (8). The outlet of the hydraulic pump / motor (2) is connected to the circuit of the hydraulic cylinder (8) and an electric switch valve is set externally and connected to its inlet. The outlet of the electric switch valve is connected to an accumulator (3). The rodless cavity control module I and the rod cavity control module II share an accumulator (3). The driver (9) is provided with a bidirectional DC-DC and is respectively connected to a super capacitor (11) and the driver (9). The rodless cavity control module I and the rod cavity control module II of the hydraulic cylinder (8) are respectively connected and controlled by the same controller (12). The controller (12) is respectively connected to the driver (9) and the bidirectional DC-DC (10) in the control module. The controller (12) is respectively connected to the electric switch valves and pressure sensors (14) of the two control modules.
2. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to claim 1, characterized in that: The electric on-off valve is a proportional flow control valve or a proportional reversing valve.
3. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to claim 2, characterized in that: A proportional flow control valve (601) is arranged in parallel in the circuit between the inlet and outlet of the hydraulic pump / motor (2), and a second proportional flow control valve (602) is arranged outside the circuit of the hydraulic pump / motor (2) outlet connected to the hydraulic cylinder (8) and connected to its inlet.
4. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to any one of claims 1 or 2, characterized in that: A non-spring check valve (4) and a spring check valve (5) are arranged on the oil circuit connecting the oil inlet of the hydraulic pump / motor (2) and the oil suction port. The inlet of the non-spring check valve (4) is connected to the oil suction port, and the outlet of the spring check valve (5) is connected to the oil suction port. The circuit between the inlet and outlet of the hydraulic pump / motor (2) is provided with a non-spring check valve (4) in parallel, and the outlet of the non-spring check valve (4) is connected to the inlet of the spring check valve (5).
5. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to claim 2, characterized in that: It also includes a second one-way valve (15), the outlet of the second proportional flow control valve (602) is connected to the inlet of the second one-way valve (15), and the outlet of the second one-way valve (15) is connected to the oil port of the hydraulic cylinder (8).
6. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to claim 5, characterized in that: The second non-return valve (15) has zero opening pressure.
7. The potential energy recovery system for an excavator boom based on a hybrid oil-electric excavator according to any one of claims 1 or 2, characterized in that: The outlet of the hydraulic pump / motor (2) is also connected to a relief valve (7), and the outlet of the relief valve (7) is connected to an oil tank (13).