Energy-saving hydraulic system with kinetic energy recovery function

Abstract

The utility model relates to an energy-saving hydraulic system with a kinetic energy recovery function, and belongs to the field of metallurgical machinery technology and petroleum machinery. The system comprises mechanical equipment, a hydraulic system connected with the mechanical equipment, and an electric power system connected with the hydraulic system. Wherein the hydraulic system comprises a hydraulic cylinder, and the output end of the hydraulic cylinder is connected with mechanical equipment; a first oil port and a second oil port are respectively formed in the top and the bottom of the hydraulic cylinder, and the hydraulic pump is respectively connected to the first oil port and the second oil port through pipelines so as to supply oil to the hydraulic cylinder; the hydraulic motor is connected to the first oil port and the second oil port through pipelines so as to receive return oil of the hydraulic cylinder, kinetic energy of mechanical equipment in the speed reduction or descending process can be recycled in the whole process, the recycled kinetic energy is converted into electric energy to be stored in the electricity storage device, and the electricity storage device uses the recycled electric energy for power supply of the hydraulic system. The system efficiency is improved, the external power supply power of the hydraulic system is greatly reduced, and energy is saved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to metallurgical machinery technology, petroleum machinery field relates to a kind of energy-saving hydraulic system with kinetic energy recovery function. BACKGROUND

[0002] There are a large number of heavy machinery in the metallurgical and oil exploitation industry, and the operation of mechanical equipment is often driven by hydraulic pressure, and these devices repeat simple reciprocating motion and repeated acceleration and deceleration during movement. In order to meet the acceleration requirements of the equipment, a high-power electric hydraulic pump is often provided for the hydraulic system to drive the equipment. When the equipment needs to decelerate, only the valve can be used to apply resistance to the hydraulic cylinder, and the kinetic energy of the mechanical equipment during deceleration is completely consumed in the hydraulic components, resulting in not only capacity loss but also heating of the hydraulic system.

[0003] The existing energy-saving hydraulic system generally uses N2 accumulator to recover the gravitational potential energy of the mechanical equipment, and due to the characteristics of N2 accumulator, the gravitational potential energy of the mechanical equipment cannot be completely recovered, and the kinetic energy of the horizontal motion equipment cannot be recovered, resulting in a large amount of energy waste. UTILITY MODEL CONTENTS

[0004] Therefore, the utility model aims to provide an energy-saving hydraulic system with kinetic energy recovery function for recovering the kinetic energy of the mechanical equipment in operation and converting the kinetic energy into electric energy to provide power to the hydraulic pump, greatly reducing the power supply power of the external power supply of the system and saving energy.

[0005] To achieve the above purpose, the utility model provides an energy-saving hydraulic system with kinetic energy recovery function: including mechanical equipment, hydraulic system connected with the mechanical equipment, and power system connected with the hydraulic system;

[0006] The hydraulic system includes a hydraulic cylinder, the output end of the hydraulic cylinder is connected with the mechanical equipment;The top and bottom of the hydraulic cylinder are respectively provided with a first oil port and a second oil port, and the hydraulic pump is connected to the first oil port and the second oil port through a pipeline to supply oil to the hydraulic cylinder;The hydraulic motor is connected to the first oil port and the second oil port through a pipeline to receive the return oil of the hydraulic cylinder;

[0007] The power system includes a power storage device, the hydraulic motor and the hydraulic pump are connected to the power storage device, the output end of the power storage device is connected to the hydraulic pump to supply power to the hydraulic pump;The hydraulic motor is connected to the input end of the power storage device through a generator to convert the external work of the hydraulic motor into electric energy storage.

[0008] Optionally, the connection lines of the hydraulic pump and the first oil port and the second oil port are respectively provided with a first valve and a third valve, and the connection lines of the hydraulic motor and the first oil port and the second oil port are respectively provided with a second valve and a fourth valve.

[0009] Optionally, the hydraulic pump is connected with the input end of the hydraulic motor, and a fifth valve is arranged on the connecting line.

[0010] Optionally, a first switch is arranged on the line connecting the hydraulic pump with the power storage device; and an external power source is connected with the power storage device, and a second switch is arranged on the connecting line.

[0011] Optionally, the energy-saving hydraulic system further comprises a bypass, one end of the bypass being connected to the line connecting the external power source with the power storage device, and the other end of the bypass being connected to the line connecting the hydraulic pump with the power storage device, and a third switch being arranged on the bypass.

[0012] Optionally, the comprehensive control system is electrically connected with the power storage device, the generator and the mechanical equipment; and the comprehensive control system is electrically connected with the first valve, the second valve, the third valve, the fourth valve and the fifth valve.

[0013] Optionally, the energy-saving hydraulic system is composed of one or more hydraulic systems in parallel.

[0014] Optionally, the plurality of parallel hydraulic systems each have an independent oil tank, or share one oil tank.

[0015] Optionally, the hydraulic cylinder is one or a plurality of cylinders arranged in parallel with each other, and the hydraulic pump is one or a plurality of pumps arranged in parallel with each other.

[0016] The energy-saving hydraulic system has the following advantages:

[0017] 1. The output power of the generator and the hydraulic motor is controlled to control the oil return pressure of the hydraulic cylinder, so that the kinetic energy of the mechanical equipment can be fully recovered, and the energy of the hydraulic system during standby operation can also be recovered, so that the energy can be recovered to the limit.

[0018] 2. Due to the unstable energy during the deceleration of the mechanical equipment, the power generation of the generator fluctuates, and the electric energy is difficult to utilize. The power storage device is arranged in the electric power system of the present application, which can store the electric energy recovered by the generator and be used to supply power to the electric hydraulic pump, so as to avoid outputting electric energy to the power grid and causing impact on the power grid.

[0019] 3. The external power source is arranged to supply power to the power storage device to compensate for the energy loss during the operation of the system.

[0020] 4. The comprehensive control system automatically controls the charging power of the power storage device according to the electric quantity of the power storage device, and ensures the service life of the power storage device under the condition of meeting the power demand of the hydraulic pump.

[0021] The other advantages, objects, and features of the present application will become more apparent in light of the following detailed description of the application. The objects and other advantages of the present application can be realized and attained by means of the instrumentalities and combinations particularly pointed out in the following description. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to make the objects, technical solutions and advantages of the present application clearer, the preferred embodiments of the present application will be described in detail below with reference to the drawings, in which:

[0023] Figure 1 A system flow chart of the energy-saving hydraulic system with kinetic energy recovery function is provided in the present application;

[0024] Reference signs:

[0025] 1, mechanical equipment; 11, oil tank; 12, hydraulic pump; 13, hydraulic cylinder; 14, first valve; 15, second valve; 16, third valve; 17, fourth valve; 18, fifth valve; 19, hydraulic motor; 21, generator; 22, power storage device; 23, first switch; 24, second switch; 25, third switch; 26, external power supply; 31, integrated control system. DETAILED DESCRIPTION

[0026] The other advantages and effects of the present application can be easily understood by those skilled in the art from the content disclosed in the present specification. The present application can also be implemented or applied in different specific embodiments, and the details in the present specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0027] It should be noted that the drawings provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0028] The same or similar reference signs in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it should be understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "front", "back", etc. are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, therefore, the terms describing the positional relationships in the drawings are only used for exemplary illustration, and cannot be understood as a limitation on the present application, for ordinary skilled persons in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0029] Please refer to Figure 1 It is an energy-saving hydraulic system with kinetic energy recovery function: including mechanical equipment 1, hydraulic system connected with mechanical equipment 1, and power system connected with hydraulic system. In the hydraulic system, the output end of the hydraulic cylinder 13 is directly connected to the mechanical equipment 1, which is used to drive or assist the movement of the mechanical equipment. The top and bottom of the hydraulic cylinder 13 are respectively provided with first oil port and second oil port, and the two oil ports are respectively connected with hydraulic pump 12 and hydraulic motor 19 through pipeline. The hydraulic pump 12 is responsible for providing necessary power for the hydraulic cylinder 13, and the hydraulic motor 19 can recover the energy of the hydraulic cylinder 13 under the drive of the comprehensive control system 31.

[0030] The power storage device 22 is connected to the output end of the hydraulic pump 12 as an energy storage unit, which provides power for the hydraulic pump 12. When the hydraulic motor 19 does work outside, the hydraulic motor 19 converts this part of energy into electric energy through the generator 21 and stores it into the power storage device 22, realizing the recovery of kinetic energy.

[0031] First valve 14 and third valve 16 are respectively arranged on the connection line of hydraulic pump 12 and first oil port and second oil port, which are used to control the flow direction and flow of hydraulic oil. Similarly, second valve 15 and fourth valve 17 are respectively arranged on the connection line of hydraulic motor 19 and first oil port and second oil port, to realize similar control function.

[0032] The fifth valve 18 is connected between the input end of the hydraulic pump 12 and the hydraulic motor 19, which is used to allow the hydraulic pump 12 to directly drive the hydraulic motor 19 in some operation modes, or isolate the two in some cases, to improve the operation efficiency and flexibility of the system.

[0033] In order to enhance the energy diversity of the system, second switch 24 is respectively arranged between generator 21 and power storage device 22, and between external power supply 26 and power storage device 22. This allows the system to obtain electric energy from external power supply 26 when needed, or automatically switch to external power supply 26 power supply mode when the electric energy generated by generator 21 is insufficient.

[0034] The third switch 25 is located on the connection bypass between the external power source 26 and the hydraulic pump 12. This switch allows, in specific cases, to power the hydraulic pump 12 directly from the external power source 26, bypassing the energy storage device 22, to face emergency or high energy demand.

[0035] In order to realize intelligent control of the whole system, a comprehensive control system 31 is introduced, which is electrically connected with the energy storage device 22, the generator 21 and the mechanical equipment 1. The comprehensive control system 31 can monitor the working state of each component, automatically adjust the valve state, switch the power supply, control the working mode of the hydraulic pump 12 and the hydraulic motor 19, etc. according to the preset logic or algorithm, so as to achieve the optimization of energy efficiency and performance.

[0036] The comprehensive control system 31 is also electrically connected with the first valve 14 to the fifth valve 18, realizing accurate control of all key valves and further improving the automation level and response speed of the system.

[0037] In order to meet the application scenarios of different scales and demands, the embodiment provides an energy-saving hydraulic system composed of multiple parallel hydraulic systems. Each hydraulic system can work independently or cooperatively to provide greater driving force or recover more kinetic energy. These parallel hydraulic systems can share an oil tank 11, or each can be equipped with an independent oil tank 11 to adapt to different installation and layout requirements.

[0038] According to actual needs, an independent oil tank 11 can be selected for each parallel hydraulic system to ensure the cleanliness and independence of the hydraulic oil; or, in order to simplify the structure and reduce the cost, all parallel systems can share an oil tank 11.

[0039] Finally, the number of hydraulic cylinders 13 and hydraulic pumps 12 is expanded. Whether it is a hydraulic cylinder 13 or a hydraulic pump 12, it can be set to single or multiple parallel configuration according to actual needs. Multiple parallel hydraulic cylinders 13 can provide greater thrust or more flexible motion control; while multiple parallel hydraulic pumps 12 can increase the hydraulic output capacity of the system and improve the overall performance and reliability of the system.

[0040] The working principle of the energy-saving hydraulic system with kinetic energy recovery function provided by the utility model is as follows:

[0041] Energy recovery state 1

[0042] When the hydraulic cylinder 13 is extended to push the mechanical device 1, the hydraulic cylinder 13 works outwardly in the early stage, the comprehensive control system 31 controls the fifth valve 18, the fourth valve 17, the first valve 14 to be closed, the second valve 15, the third valve 16 to be opened, the hydraulic motor 19 is in the state of not working outwardly, the hydraulic pump 12 is started to push the mechanical device 1. When the mechanical device 1 needs to decelerate, the comprehensive control system 31 controls the hydraulic pump 12 to reduce the power or stop, and simultaneously starts the hydraulic motor 19 to work outwardly, controls the deceleration of the mechanical device 1 by adjusting the output power of the generator 21, and the generator 21 charges the power storage device 22.

[0043] Energy recovery state 2

[0044] When the hydraulic cylinder 13 is retracted to pull the mechanical device 1, the comprehensive control system 31 controls the second valve 15, the third valve 16, the fifth valve 18 to be closed, the first valve 14, the fourth valve 17 to be opened;

[0045] If the mechanical device 1 is in a horizontal state and needs the hydraulic pump 12 to work to move, the comprehensive control system 31 controls the hydraulic motor 19 not to work outwardly, and the hydraulic pump 12 is started to start pulling the mechanical device 1, when the mechanical device 1 needs to decelerate in the later stage of the pulling, the comprehensive control system 31 controls the hydraulic pump 12 to reduce the power or stop, and simultaneously starts the hydraulic motor 19 to work outwardly, controls the deceleration of the mechanical device 1 by adjusting the output power of the generator 21, and the generator 21 charges the power storage device 22.

[0046] If the mechanical device 1 is in a vertical or inclined state, and the hydraulic cylinder 13 can be retracted by the potential energy of the mechanical device 1, the comprehensive control system 31 directly controls the hydraulic pump 12 to reduce the power or stop, and simultaneously starts the hydraulic motor 19 to work outwardly, controls the deceleration of the mechanical device 1 by adjusting the output power of the generator 21, and the generator 21 charges the power storage device 22.

[0047] Energy recovery state 3

[0048] When the hydraulic system is provided with the fifth valve 18, the hydraulic pump 12 needs to be continuously operated, and the mechanical device 1 is in a stopped state, the comprehensive control system 31 controls the first valve 14, the second valve 15, the third valve 16, the fourth valve 17 to be closed, and the fifth valve 18 to be opened, the comprehensive control system 31 controls the output power of the hydraulic motor 19 according to the minimum output power requirement of the hydraulic pump 12, drives the generator 21 to charge the power storage device 22.

[0049] Energy use and control

[0050] The energy recovered by the system is converted into electric energy by the hydraulic motor 19 and the generator 21 and stored in the electric storage device 22, which supplies power to the hydraulic pump 12. Due to the energy loss during the operation of the system, the lost energy is supplemented to the electric storage device 22 by the external power supply 26.

[0051] The electric quantity of the electric storage device 22 is controlled by the integrated control system 31. When the electric quantity of the electric storage device 22 is higher than a set value, such as 80%, the external power supply 26 stops charging the electric storage device 22. When the electric quantity of the electric storage device 22 is lower than a set value, such as 20%, the external power supply 26 starts charging the electric storage device 22.

[0052] According to the needs, the power system can be switched by the first switching switch 23, the second switching switch 24 and the third switching switch 25. When the first switching switch 23 and the second switching switch 24 are connected and the third switching switch 25 is disconnected, the electric storage device 22 is put into operation; when the first switching switch 23 and the second switching switch 24 are disconnected and the third switching switch 25 is connected, the electric storage device 22 stops operating and the power supply of the hydraulic pump 12 is provided by the external power supply 26.

[0053] It should be noted that the above is only one embodiment of the present application, but the protection scope is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered within the protection scope of the present application. For example, the first valve 14 and the second valve 15 are combined into one three-way valve, the third valve 16 and the fourth valve 17 are combined into one three-way valve, the oil tank 11 is combined when multiple hydraulic systems are connected in parallel, and the hydraulic cylinder 13 is increased, etc.

[0054] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limited. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions, which should be covered within the scope of the claims of the present application.

[0055] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limited. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions, which should be covered within the scope of the claims of the present application.

Claims

1. An energy-saving hydraulic system with kinetic energy recovery function, characterized in that: The energy-saving hydraulic system comprises a mechanical device (1), a hydraulic system connected with the mechanical device (1), and an electric system connected with the hydraulic system. The hydraulic system comprises a hydraulic cylinder (13), the output end of the hydraulic cylinder (13) being connected with the mechanical device (1); the top and bottom of the hydraulic cylinder (13) are respectively provided with a first oil port and a second oil port, a hydraulic pump (12) being connected with the first oil port and the second oil port through pipelines to supply oil to the hydraulic cylinder (13); and a hydraulic motor (19) being connected with the first oil port and the second oil port through pipelines to receive the back oil of the hydraulic cylinder (13). The electric system comprises a power storage device (22), the hydraulic pump (12) and the hydraulic motor (19) being connected with the power storage device (22), the output end of the power storage device (22) being connected with the hydraulic pump (12) to supply energy to the hydraulic pump (12); and the hydraulic motor (19) being connected with the input end of the power storage device (22) through a generator (21) to convert the external work of the hydraulic motor (19) into electric energy to be stored through the generator (21).

2. The energy-saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: First and third valves (14) and (16) are respectively arranged on the connection lines of the hydraulic pump (12) and the first and second oil ports, and second and fourth valves (15) and (17) are respectively arranged on the connection lines of the hydraulic motor (19) and the first and second oil ports.

3. The energy-saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: The hydraulic pump (12) is connected with the input end of the hydraulic motor (19), and a fifth valve (18) is arranged on the connection line thereof.

4. The energy-saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: A first switch (23) is arranged on the line through which the hydraulic pump (12) is connected with the power storage device (22), and a second switch (24) is arranged on the line through which an external power supply (26) is connected with the power storage device (22).

5. The energy saving hydraulic system with kinetic energy recovery function according to claim 4, characterized in that: A connection bypass is arranged, one end of the connection bypass being connected to the line through which the external power supply (26) is connected with the power storage device (22), and the other end of the connection bypass being connected to the line through which the hydraulic pump (12) is connected with the power storage device (22), and a third switch (25) being arranged on the connection bypass.

6. The energy saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: A comprehensive control system (31) is electrically connected with the power storage device (22), the generator (21) and the mechanical device (1), and is electrically connected with the first, second, third, fourth and fifth valves (14), (15), (16), (17) and (18).

7. The energy saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: The hydraulic system further comprises an oil tank (11), the input end of the hydraulic pump (12) being connected with the oil tank (11), and the output end of the hydraulic motor (19) being connected with the oil tank (11).

8. The energy saving hydraulic system with kinetic energy recovery function according to claim 7, characterized in that: The energy-saving hydraulic system is composed of one or more hydraulic systems in parallel.

9. The energy saving hydraulic system with kinetic energy recovery function according to claim 8, characterized in that: The plurality of parallel hydraulic systems are each provided with an independent oil tank (11), or share one oil tank (11).

10. The energy saving hydraulic system with kinetic energy recovery function according to claim 1, characterized in that: The hydraulic cylinder (13) is one or a plurality of parallel hydraulic cylinders, and the hydraulic pump (12) is one or a plurality of parallel hydraulic pumps.

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