A range extending energy saving system for a construction machine

Abstract

This invention discloses a range-extended energy-saving system for construction machinery, belonging to the technical field of energy-saving systems for construction machinery. It includes an energy storage mechanism and a range extender mechanism, connected to the energy storage mechanism. The range extender mechanism includes a generator set, which is electrically connected to a battery. The battery is connected to a permanent magnet synchronous motor, and the permanent magnet synchronous motor is connected to a hydraulic pump. This invention employs the aforementioned range-extended energy-saving system for construction machinery. The range extender mechanism converts the mechanical energy generated during engine operation into electrical energy to power the active hydraulic components. The energy storage hydraulic components convert the potential energy of the excavator boom during descent into mechanical energy, providing a boost when the excavator boom rises, thus achieving energy savings. The combined action of the generator set, battery, and permanent magnet synchronous motor ensures that the operation of the permanent magnet synchronous motor is unaffected by engine speed fluctuations, achieving peak shaving and valley filling of speed and fuel consumption, and guaranteeing stable operation.

Description

Technical Field

[0001] This invention relates to the field of energy-saving systems for construction machinery, and in particular to a range-extended energy-saving system for construction machinery. Background Technology

[0002] Currently, excavators and other construction machinery generally employ a traditional pure fuel-powered mechanical transmission + hydraulic drive system. The core power source is a diesel engine directly driving the main hydraulic pump, which in turn drives various hydraulic actuators to complete digging, lifting, slewing, and traveling operations. During sudden heavy-load operations such as lifting the excavator boom and digging, the main hydraulic pump and the front-end power source are subjected to impact loads. Traditional solutions rely solely on the engine or electric motor's output power, requiring the power unit to frequently handle peak loads. This not only increases fuel consumption and accelerates wear on power components but also easily leads to problems such as delayed response, hydraulic pressure fluctuations, and overall machine vibration, affecting operational smoothness and the user experience. Furthermore, the excavator boom is a high-frequency lifting mechanism. The significant amount of gravitational potential energy generated when the boom descends during operation cannot be effectively recovered and utilized in traditional models or ordinary pure electric motor models. This energy is mostly dissipated through hydraulic throttling and frictional heat generation, resulting in serious energy waste and a rapid increase in hydraulic system oil temperature, accelerating the aging of hydraulic components and shortening their lifespan. Summary of the Invention

[0003] The purpose of this invention is to provide a range-extended energy-saving system for construction machinery. The system is equipped with a range-extending mechanism that converts the mechanical energy of the engine during operation into electrical energy to power the active hydraulic components. The energy storage hydraulic components can convert the potential energy of the excavator boom during descent into mechanical energy and provide a boost when the excavator boom rises, thereby achieving energy saving. The generator set, battery, and permanent magnet synchronous motor work together to ensure that the operation of the permanent magnet synchronous motor is not affected by engine speed fluctuations, thereby achieving peak shaving and valley filling of speed and fuel consumption and ensuring stable operation.

[0004] To achieve the above objectives, the present invention provides a range-extended energy-saving system for engineering machinery, including an energy storage mechanism and a range extender mechanism. The range extender mechanism is connected to the energy storage mechanism. The range extender mechanism includes a generator set, which is electrically connected to a battery. The battery is connected to a permanent magnet synchronous motor, and the permanent magnet synchronous motor is connected to a hydraulic pump.

[0005] Preferably, the generator set includes an engine and a generator, with the engine and generator being coaxially and directly connected.

[0006] Preferably, both the generator set and the battery are connected to the overall controller.

[0007] Preferably, the energy storage mechanism includes an energy storage hydraulic component and an active hydraulic component. The energy storage hydraulic component includes an energy storage hydraulic cylinder, which is connected to the energy storage device through an energy storage valve group.

[0008] Preferably, the accumulator includes an energy storage shell, an inflation valve is provided at the top of the energy storage shell, an oil valve body interface is provided at the bottom of the energy storage shell, a mushroom valve is provided inside the oil valve body interface, and a telescopic air bladder is provided inside the energy storage shell, which is connected to the inflation valve.

[0009] Preferably, a blind plug is provided on the oil valve body interface, and a telescopic spring is connected between the mushroom valve and the oil valve body interface.

[0010] Preferably, the active hydraulic assembly includes two active hydraulic cylinders, both of which are connected to a hydraulic pump via an active valve group, and the hydraulic pump is connected to a hydraulic oil tank.

[0011] Preferably, the active hydraulic cylinder and the accumulator hydraulic cylinder have the same structure, and both active hydraulic cylinders and one accumulator hydraulic cylinder are hinged to the excavator boom.

[0012] Therefore, the present invention adopts the above-mentioned range-extended energy-saving system for engineering machinery. The range-extending mechanism converts the mechanical energy of the engine during operation into electrical energy to provide power for the active hydraulic components. The energy storage hydraulic components can convert the potential energy of the excavator boom descending into mechanical energy and provide a boost when the excavator boom rises, thereby achieving energy saving. The generator set, battery and permanent magnet synchronous motor work together to ensure that the operation of the permanent magnet synchronous motor is not affected by the engine speed fluctuation, thereby achieving peak shaving and valley filling of speed and fuel consumption and ensuring stable operation.

[0013] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0014] Figure 1 This is a simplified structural diagram of the range extender mechanism of a range extender energy-saving system for engineering machinery according to the present invention; Figure 2 This is a schematic diagram of the energy storage mechanism of a range-extended energy-saving system for engineering machinery according to the present invention; Figure 3 This is a structural diagram of an energy storage device for a range-extended energy-saving system of engineering machinery according to the present invention.

[0015] Figure Labels 1. Generator set; 2. Battery; 3. Permanent magnet synchronous motor; 4. Hydraulic pump; 5. Controller; 6. Energy storage housing; 7. Air charging valve; 8. Oil valve body interface; 9. Mushroom valve; 10. Telescopic airbag; 11. Blind plug; 12. Telescopic spring. Detailed Implementation

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention. Furthermore, it should be understood that after reading the contents of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims and are all within the protection scope of the present invention.

[0017] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0018] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0019] Example 1 like Figures 1 to 3As shown, this invention provides a range-extended energy-saving system for engineering machinery, including an energy storage mechanism and a range extender mechanism. The range extender mechanism is connected to the energy storage mechanism. The range extender mechanism includes a generator set 1, which is connected to a battery 2. The generator set 1 includes an engine and a generator, forming a composite power generation component. The engine and generator are coaxially and directly connected, with the engine directly driving the generator. This results in a low failure rate, a short transmission path, direct power transmission, reduced energy consumption, and a compact structure, saving installation space. When the engine is working, it outputs the chemical energy of burning fuel as rotational mechanical energy. The generator converts the engine's mechanical energy into electrical energy, which is stored in the battery 2. When the battery 2 is low on power, the generator set 1 starts, continuously replenishing the battery 2 with electrical energy. The battery 2 is electrically connected to a permanent magnet synchronous motor 3, which is connected to a hydraulic pump 4. The permanent magnet synchronous motor 3 converts electrical energy into mechanical torque, driving the hydraulic pump 4 to operate. The hydraulic pump 4 converts mechanical energy into hydraulic energy, providing pressurized oil for the hydraulic operation of the entire machine. The generator set 1, the battery 2 and the permanent magnet synchronous motor 3 work together to ensure that the operation of the permanent magnet synchronous motor 3 is not affected by the engine speed fluctuation, thereby achieving peak shaving and valley filling of speed and fuel consumption, ensuring stable operation and reducing engine energy consumption when the excavator boom is working.

[0020] Both generator set 1 and battery 2 are connected to the overall controller 5. The overall controller 5 can control the engine operation to improve engine performance and fuel economy; control the generator operation to ensure stable power output, achieve coordinated matching of various power units, stabilize power output, and avoid voltage and power fluctuations; manage the charging and discharging process of battery 2 to ensure its safe operation and optimize its range. The overall controller 5 is used to control the working mode of generator set 1 and battery 2, coordinate energy matching and optimization, realize intelligent energy management, improve overall efficiency and performance, start generator set 1 to generate electricity when battery 2's charge is below 20%, and automatically shut down generator set 1 when the battery charge reaches 100%, ensuring normal operation of the vehicle.

[0021] The energy storage mechanism includes an energy storage hydraulic assembly and an active hydraulic assembly. The energy storage hydraulic assembly stores energy when the excavator boom descends under the action of the active hydraulic assembly and provides main thrust when the excavator boom rises under the action of the active hydraulic assembly. The energy storage hydraulic assembly includes an energy storage hydraulic cylinder, which is connected to the accumulator via an energy storage valve assembly. The extension and retraction of the energy storage hydraulic cylinder during excavator boom operation drives the flow of hydraulic oil inside the cylinder. The energy storage valve assembly regulates the circulation of hydraulic oil between the energy storage hydraulic cylinder and the accumulator, thereby achieving energy storage and release. The energy storage valve assembly controls the on / off of the oil circuit between the energy storage hydraulic cylinder and the accumulator, regulates pressure, and enables one-way locking.

[0022] The accumulator includes an accumulator housing 6, which is a pressure-bearing body capable of sealing and containing oil and gas media. An inflation valve 7 is located at the top of the accumulator housing 6, allowing it to connect to an inflation device to inject inert gas into the telescopic air bladder 10, establishing pre-charge pressure. An oil valve body interface 8 is located at the bottom of the accumulator housing 6, with a blind plug 11 installed on it. The oil valve body interface 8 serves as a hydraulic oil inlet and outlet channel, connecting to the accumulator valve assembly. The blind plug 11 seals off spare or unconnected hydraulic interfaces, preventing hydraulic oil leakage under system pressure and preventing dust, moisture, or impurities from entering the internal oil circuit, ensuring the cleanliness and reliability of the hydraulic system. It also preserves the interface structure for future functional upgrades without replacing the entire valve body, and temporarily seals pressurized interfaces during disassembly or component replacement, reducing the risk of accidental splashing or high-pressure release. A mushroom-shaped valve 9 is installed inside the oil valve body interface 8. A telescopic spring 12 connects the mushroom-shaped valve 9 to the oil valve body interface 8. The mushroom-shaped valve 9 is installed at the oil inlet and is shaped like a mushroom head. It can be opened under the action of hydraulic oil pressure to allow oil to enter and exit. When there is no pressure or low pressure, it is closed under the action of the elastic potential energy of the telescopic spring 12 to prevent oil backflow or abnormal impact. A telescopic air bladder 10 is installed inside the energy storage housing 6. The telescopic air bladder 10 is connected to the inflation valve 7. The telescopic air bladder 10 can separate hydraulic oil and inert gas. When the excavator boom drives the energy storage hydraulic cylinder to retract, the oil compresses the inert gas in the telescopic air bladder 10 to store energy. When the excavator boom drives the energy storage hydraulic cylinder to extend, the inert gas in the telescopic air bladder 10 expands and releases energy, pushing the oil back into the system to replenish the flow, stabilize the pressure, and assist the excavator boom, reducing the peak load of the permanent magnet synchronous motor 3 and the hydraulic pump 4.

[0023] The active hydraulic assembly includes two active hydraulic cylinders, both connected to a hydraulic pump via an active valve group. The hydraulic pump is connected to a hydraulic oil tank. The hydraulic oil tank stores, cools, and filters the hydraulic oil, supplying oil to the entire hydraulic circuit. The active valve group distributes oil circuits and controls the extension and retraction of the active hydraulic cylinders. The two active hydraulic cylinders convert hydraulic energy into linear mechanical energy, driving the excavator boom to perform digging, lifting, and other operations. Their paired arrangement provides strong load capacity and balanced force distribution, improving output thrust and operational smoothness. The pressurized oil output from the hydraulic pump is distributed through the valve group, driving the two hydraulic cylinders to operate synchronously, completing the engineering machinery operations.

[0024] The active hydraulic cylinder and the accumulator hydraulic cylinder have the same structure, and the commonality of components can reduce production and maintenance costs. Furthermore, both active hydraulic cylinders and one accumulator hydraulic cylinder are hinged to the excavator boom, resulting in a short energy recovery path, reducing energy loss and improving energy recovery efficiency. The structure and connections of each component in both the accumulator and active hydraulic assemblies utilize existing technologies.

[0025] Therefore, the present invention adopts the above-mentioned range-extended energy-saving system for engineering machinery. The range-extending mechanism converts the mechanical energy of the engine during operation into electrical energy to provide power for the active hydraulic components. The energy storage hydraulic components can convert the potential energy of the excavator boom descending into mechanical energy and provide a boost when the excavator boom rises, thereby achieving energy saving. The generator set, battery and permanent magnet synchronous motor work together to ensure that the operation of the permanent magnet synchronous motor is not affected by the engine speed fluctuation, thereby achieving peak shaving and valley filling of speed and fuel consumption and ensuring stable operation.

[0026] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A range extending energy saving system for a construction machine, characterized by: It includes an energy storage mechanism and a range extender mechanism. The range extender mechanism is connected to the energy storage mechanism. The range extender mechanism includes a generator set, which is electrically connected to a battery. The battery is connected to a permanent magnet synchronous motor, and the permanent magnet synchronous motor is connected to a hydraulic pump.

2. The range extending energy saving system of the engineering machine according to claim 1, characterized in that: A generator set consists of an engine and a generator, with the engine and generator directly connected coaxially.

3. The range extending energy saving system of the engineering machine according to claim 2, characterized in that: Both the generator set and the battery are connected to the overall controller.

4. The range extending energy saving system of the engineering machine according to claim 3, characterized in that: The energy storage mechanism includes an energy storage hydraulic component and an active hydraulic component. The energy storage hydraulic component includes an energy storage hydraulic cylinder, which is connected to the accumulator through an energy storage valve group.

5. The range extending energy saving system of the engineering machine as claimed in claim 4 wherein: The accumulator includes an energy storage shell, an inflation valve at the top of the energy storage shell, an oil valve body interface at the bottom of the energy storage shell, a mushroom-shaped valve inside the oil valve body interface, and a telescopic air bladder inside the energy storage shell, which is connected to the inflation valve.

6. The range extending energy saving system of a working machine according to claim 5, characterized in that: A blind plug is provided on the oil valve body interface, and a telescopic spring connects the mushroom valve to the oil valve body interface.

7. The range extending energy saving system of a construction machine according to claim 6, characterized by: The active hydraulic assembly includes two active hydraulic cylinders, both of which are connected to a hydraulic pump via an active valve group. The hydraulic pump is connected to a hydraulic oil tank.

8. The range-extended energy-saving system for engineering machinery according to claim 7, characterized in that: The active hydraulic cylinder and the accumulator hydraulic cylinder have the same structure, and both active hydraulic cylinders and one accumulator hydraulic cylinder are hinged to the excavator boom.

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