Hybrid power system and control method thereof
By introducing a clutch into the hybrid system to achieve coupling/decoupling between the engine and the generator motor, the operating modes are enriched, the problem of the engine speed not being able to be adjusted independently is solved, and the system's energy saving and power output capabilities are improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANDONG LINGONG CONSTR MACHINERY CO LTD
- Filing Date
- 2026-03-24
- Publication Date
- 2026-05-12
AI Technical Summary
In existing clutchless hybrid systems, the engine and generator motor are coaxial and run at the same speed. The engine speed cannot be adjusted independently, resulting in weaker energy-saving performance compared to hybrid systems with clutches. Furthermore, the constant coupling between the engine and generator motor limits the operating scenarios of the hybrid system.
By introducing a clutch to achieve coupling/decoupling between the engine and the generator motor, the system's operating modes are enriched, the clutch state is controlled to adapt to different load requirements, and combined with the state of charge of the energy storage element, power output and energy saving are achieved.
It increases the freedom of engine speed, enables more flexible power mode switching, reduces dependence on pure oil output, and improves the system's energy-saving effect and power output capability.
Smart Images
Figure CN122009134A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of control technology related to hybrid power systems, and in particular to a hybrid power system and its control method. Background Technology
[0002] Existing clutchless hybrid power systems often employ a mechanical coupling structure of "engine-transfer case-generator motor → pump set-actuator". In this system, the engine and generator motor are always mechanically coupled through the transfer case. The engine cannot drive the pump set independently, and the transfer case does not have the ability to disconnect the mechanical coupling between the engine and the generator motor. The generator motor has both driving and power generation functions.
[0003] While existing clutchless hybrid systems are simple in structure, lower in cost, and have a fast system response, they have a core disadvantage: limited freedom of engine operating conditions. Specifically, when the engine and generator motor are coaxially connected through a transfer case, the engine and generator motor are coaxial and at the same speed, and the engine speed cannot be independently adjusted. When the load demand is low, the engine cannot operate independently of the generator motor in the optimal speed range, resulting in weaker energy-saving performance than hybrid systems with a clutch. Furthermore, the constant coupling between the engine and generator motor limits the operating scenarios of the hybrid system. Summary of the Invention
[0004] In view of this, the purpose of this application is to provide at least one hybrid power system and its control method, which realizes the coupling / decoupling between the engine and the generator motor through a clutch, enriches the system's operating modes, can be applied to more complex operating conditions, reduces dependence on pure oil output, and balances power output and energy saving.
[0005] This application mainly includes the following aspects: In a first aspect, embodiments of this application provide a control method for a hybrid power system. The hybrid power system includes an engine, a clutch, a generator motor, an energy storage element, a pump set, and an actuator. The engine is connected to the actuator via the clutch, the generator motor, and the pump set, and the energy storage element is connected to the generator motor. The method includes: acquiring the regulation and control mode corresponding to the hybrid power system; if the regulation and control mode corresponding to the hybrid power system is an intelligent mode, then performing: determining the current operating condition of the hybrid power system based on the load demand power of the excavator; determining the target drive mode of the hybrid power system based on the current operating condition of the hybrid power system and the state of charge of the energy storage element; and controlling the state of the clutch to cause the hybrid power system to output the load demand power in the target drive mode.
[0006] In one possible implementation, the step of determining the current operating condition of the hybrid power system based on the load demand power corresponding to the excavator includes: if the load demand power is less than the lower limit of the engine's efficient operating range, then the current operating condition of the hybrid power system is determined to be a light load condition; if the load demand power is within the engine's efficient operating range, then the current operating condition of the hybrid power system is determined to be a medium load condition; if the load demand power is greater than the upper limit of the engine's efficient operating range and / or the load demand power is greater than or equal to the engine's rated power, then the current operating condition of the hybrid power system is determined to be a heavy load condition.
[0007] In one possible implementation, the step of determining the target driving mode of the hybrid power system based on the current operating conditions of the hybrid power system and the state of charge of the energy storage element includes: when the operating conditions of the hybrid power system are light load conditions, performing the following: if the state of charge of the energy storage element is in the high state of charge range, then determining the target operating mode of the hybrid power system as a pure electric drive mode; if the state of charge of the energy storage element is in the medium state of charge range, then determining the target operating mode of the hybrid power system as an electric main drive with oil auxiliary drive mode; if the state of charge of the energy storage element is in the low state of charge range, then determining the target operating mode of the hybrid power system based on the vehicle operating conditions.
[0008] In one possible implementation, the step of determining the target operating mode of the hybrid system based on the vehicle's operating state includes: if the vehicle is in an operating state, the target operating mode of the hybrid system is determined to be a pure gasoline drive mode; if the vehicle is in a non-operating state, the target operating mode of the hybrid system is determined to be an energy storage and charging mode.
[0009] In one possible implementation, the step of determining the target driving mode of the hybrid power system based on the current operating condition of the hybrid power system and the state of charge of the energy storage element includes: when the current operating condition of the hybrid power system is a medium load condition, performing the following: if the state of charge of the energy storage element is in the high state of charge range, then determining the target operating mode of the hybrid power system as electric-main-gasoline-assisted drive mode; if the state of charge of the energy storage element is in the medium state of charge range, then determining the target operating mode of the hybrid power system as gasoline-main-electric-assisted drive mode; if the state of charge of the energy storage element is in the low state of charge range, then determining the vehicle operating state, and based on the vehicle state, determining the target operating mode of the hybrid power system as energy storage charging mode.
[0010] In one possible implementation, the step of determining the target drive mode of the hybrid power system based on the current operating condition of the hybrid power system and the state of charge of the energy storage element includes: when the current operating condition of the hybrid power system is a heavy load condition, performing the following: if the state of charge of the energy storage element is in the high state of charge range or the medium state of charge range, then determining the target operating mode of the hybrid power system as a combined full output drive mode; if the state of charge of the energy storage element is in the low state of charge range, then determining the target operating mode of the hybrid power system as a pure oil drive mode.
[0011] In one possible implementation, the step of controlling the state of the clutch to enable the hybrid system to output the load demand power in the target drive mode includes: if the target drive mode is a pure electric drive mode, controlling the clutch to disengage to disconnect the engine and the generator motor, causing the engine to shut off or idle, and controlling the generator motor to independently output the load demand power to drive the pump assembly; if the target drive mode is a pure gasoline drive mode, controlling the clutch to disengage to disconnect the engine and the generator motor, and controlling the engine to independently output the load demand power to drive the pump assembly.
[0012] In one possible implementation, the step of controlling the state of the clutch to enable the hybrid system to output the load-demand power in the target drive mode further includes: if the target drive mode is an electric-main-cylinder-auxiliary drive mode, then controlling the clutch to engage, controlling the generator motor to output main power, and controlling the engine to compensate for the load-demand power output beyond the main power; if the target drive mode is an energy storage and charging mode, then controlling the clutch to engage, controlling the engine to operate at the optimal fuel consumption speed, and driving the generator motor to generate electricity at full power to charge the energy storage element; if the target drive mode is a diesel-main-electric-auxiliary drive mode, then controlling the clutch to engage, controlling the engine to operate at high-efficiency drive to output main torque, and the generator motor to output auxiliary torque in electric mode, so that the engine and generator motor work together to meet the load-demand power output; if the target drive mode is a combined full-output drive mode, then controlling the clutch to engage, controlling the engine to operate at rated power to output maximum continuous torque, and simultaneously controlling the generator motor to provide auxiliary output at peak power.
[0013] In one possible implementation, the method further includes: if the adjustment and control mode corresponding to the hybrid power system is a human-machine interaction mode, then: determine the target drive mode of the hybrid power system according to the pre-entered state of charge of the energy storage element and the operating condition of the hybrid power system; control the state of the clutch so that the hybrid power system outputs the load demand power in the target drive mode.
[0014] Secondly, this application embodiment also provides a hybrid power system, which includes an engine, a clutch, a generator motor, an energy storage element, a pump set, and an actuator. The engine is connected to the actuator through the clutch, the generator motor, and the pump set. The energy storage element is connected to the generator motor. The engine, clutch, generator motor, energy storage element, and pump set are all connected to a vehicle controller. The vehicle controller operates the control method of the hybrid power system provided in any of the above possible embodiments.
[0015] This application provides a hybrid power system and its control method. An engine is connected to an actuator via a clutch, a generator motor, and a pump set. The method includes: acquiring the corresponding adjustment and control mode of the hybrid power system; if the adjustment and control mode is an intelligent mode, then: determining the current operating condition of the hybrid power system based on the load demand power of the excavator; determining the target drive mode of the hybrid power system based on the current operating condition of the hybrid power system and the state of charge of the energy storage element; and controlling the state of the clutch to allow the hybrid power system to output the load demand power in the target drive mode. This application achieves coupling / decoupling between the engine and the generator motor through a clutch, enriching the system's operating modes, enabling it to be applicable to more complex operating conditions, reducing dependence on pure oil output, and balancing power output and energy saving.
[0016] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 A schematic diagram of an existing clutchless hybrid power system architecture is shown; Figure 2 This application provides a schematic diagram of the architecture of a hybrid power system according to an embodiment of the present application. Figure 3 This application illustrates a second schematic diagram of the architecture of a conventional hybrid power system provided in an embodiment of the present application. Figure 4 This application provides a third schematic diagram of the architecture of a conventional hybrid power system. Figure 5 A flowchart of a control method for a hybrid power system provided in an embodiment of this application is shown; Figure 6 This paper illustrates a control flowchart of a hybrid power system under light load conditions according to an embodiment of this application. Figure 7 This paper illustrates a control flowchart of a hybrid power system under medium load conditions according to an embodiment of this application. Figure 8 This paper illustrates a control flowchart of a hybrid power system under heavy load conditions according to an embodiment of this application. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.
[0020] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0021] Against the backdrop of energy conservation and emission reduction, the construction machinery industry is accelerating its green transformation. New energy technologies, due to their advantages such as low operating costs, energy conservation and emission reduction, and strong power, are widely used in construction machinery products. Excavators, as one of the main types of machinery in the construction machinery field, experience drastic load fluctuations due to their digging operations. They periodically switch between no-load, light-load, medium-heavy-load, and even overload conditions. These load changes cause significant fluctuations in engine torque and speed, resulting in the engine frequently operating under transient conditions, leading to poor fuel economy and emissions. To improve fuel economy and emissions, medium and large-sized excavators commonly adopt hybrid electric powertrain technology, increasing work efficiency, reducing fuel consumption, and meeting energy conservation and emission reduction requirements. Further improvements in mechanical structure can further enhance the excavator's operational efficiency and achieve even greater energy savings.
[0022] Please see Figure 1 , Figure 1 A schematic diagram of an existing clutchless hybrid power system architecture is shown. Figure 1 As shown, existing clutchless hybrid power systems typically employ a mechanical coupling structure of "engine 1 - transfer case 2 - generator motor 3 → pump set 4 - actuator 5". In this system, engine 1 and generator motor 3 are always mechanically coupled through transfer case 2. Engine 1 cannot independently drive pump set 4, and transfer case 2 lacks the ability to disconnect the mechanical coupling between engine 1 and generator motor 3. Generator motor 3 performs both driving and power generation functions, without a clutch to switch between coupling / decoupling modes. Energy storage element 6 is connected to the bus side, such as... Figure 1 The existing clutchless hybrid power system shown has the following corresponding operating modes: pure generator drive mode, energy storage charging mode, hybrid drive mode, and energy recovery mode.
[0023] The energy flow in pure engine-driven mode is: engine 1 → transfer case 2 → generator motor 3 (as a motor) → pump set 4 → actuator 5. The applicable scenario is: when the energy storage element 6 has insufficient power / energy and the load demand is stable, the engine 1 directly drives the generator motor 3 to drive the pump set 4 to work, providing power to the actuator 5.
[0024] The energy flow in the energy storage and charging mode is: engine 1 → transfer case 2 → generator motor 3 (as a generator) → energy storage element 6. The applicable scenario is: when the load demand is low or when idling, engine 1 works in the high-efficiency range, drives generator motor 3 to generate electricity, and stores the excess energy in energy storage element 6 to prepare for subsequent high load or pure electric mode.
[0025] The energy flow of the hybrid drive mode is: engine 1 → transfer case 2 → generator motor 3 (electric motor) + energy storage element 6 → pump group 4 → actuator 5. The applicable scenario is: when the actuator 5 is under peak load (such as acceleration or heavy-load operation), the engine 1 and the energy storage element 6 output power together, and the generator motor 3 drives the pump group with superimposed torque to meet the short-term high power demand.
[0026] The energy flow in the energy recovery mode is: actuator 5 → pump group 4 → generator motor 3 (as a generator) → energy storage element 6. The applicable scenario is: when the actuator 5 decelerates, brakes, or lowers the load, the pump group 4 reverses to drive the generator motor 3 to generate electricity, recovering mechanical / hydraulic energy as electrical energy for storage, thereby improving the system's energy efficiency.
[0027] As can be seen from the above, although the existing clutchless hybrid system has a simple structure, reduced cost, and fast system response, it has a core disadvantage: the operating freedom of engine 1 is limited. Specifically, when engine 1 and generator motor 3 are coaxially connected through transfer case 2, engine 1 and generator motor 3 are coaxial and at the same speed. The speed of engine 1 cannot be adjusted independently. When the load demand is low, engine 1 cannot operate independently of generator motor 3 in the optimal speed range, and the energy saving effect is weaker than that of hybrid system with clutch.
[0028] Furthermore, because the existing hybrid power system is always mechanically coupled with the generator motor 3, the engine connection cannot be disconnected. As a result, the system lacks a pure electric operation mode, has a lot of energy waste, weak continuous working capacity, and cannot achieve long-term pure electric operation. Moreover, when the engine 1 is cold-started, the generator motor 3 needs to drive the shaft system to rotate to start the speed. Under the rigid mechanical connection, the torque fluctuation of the engine 1 ignition will be directly transmitted to the pump group 4, which will cause impact.
[0029] Based on this, this application provides a hybrid power system and its control method, which achieves controllable coupling / decoupling between the generator and the generator motor through a clutch, allowing the engine to operate independently within its optimal speed range while enabling flexible switching of the hybrid power system's operating modes, thus balancing power and energy saving, as detailed below: Please see Figure 2 , Figure 2 A schematic diagram of the architecture of a hybrid power system provided in an embodiment of this application is shown. Figure 2 As shown, the hybrid power system provided in this application includes an engine 1, a clutch 7, a generator motor 3, an energy storage element 6, a pump set 4, and an actuator 5. The engine 1 is connected to the generator motor 3 through the clutch 7, the generator motor 3 is connected to the actuator 5 through the pump set 4, and the energy storage element 6 is connected to the generator motor 3.
[0030] Preferably, the engine 1, clutch 7, generator motor 3, energy storage element 6, and pump group 4 are all connected to the vehicle control unit (VCU). The VCU controls the engine 1, clutch 7, generator motor 3, energy storage element 6, and pump group 4 to realize the power output of the hybrid power system. Specifically, by controlling the state of the clutch 7, the coupling / decoupling between the engine 1 and the generator motor 3 is realized. When the clutch 7 is engaged, the mechanical shaft between the engine 1 and the generator motor 3 is coupled. When the clutch 7 is disengaged, the mechanical shaft between the engine 1 and the generator motor 3 is decoupled, and the engine 1 can independently output power to the pump group 4.
[0031] Please see Figure 3 , Figure 3 This is a second schematic diagram of the architecture of a conventional hybrid power system provided in an embodiment of this application. Figure 3 As shown, the existing technology in Figure 1 Based on the hybrid power system shown, an improvement is made by connecting a clutch 7 in series between the engine area and the transfer case 2. The output of the transfer case is divided into two branches. One branch is connected to the actuator 5 through the pump set 4, and the other branch is connected to the generator motor 3. Similarly, the energy storage element 6 is connected to the generator motor 3. The transfer case 2 splits the power to the generator motor 3 and the pump set 4. Under the control of the vehicle controller VCU, the clutch 7 decouples / couples the engine 1 and the transfer case 2 to achieve multiple working modes. Specifically, when the clutch 7 is disengaged, the engine 1 and the transfer case 2 are decoupled. At this time, the engine 1 cannot participate in the pump set drive (i.e., the pure oil drive mode is missing). The generator motor 3 drives the actuator 5 alone through the pump set 4. When the engine 1 and the transfer case 2 are coupled, the engine 1 and the generator motor 3 jointly drive the pump set 4.
[0032] Therefore, Figure 3 The existing hybrid system shown also introduces a clutch 7, but its clutch 7 is connected in series between the engine 1 and the transfer case 2, which not only makes the structure complex and causes excessive cost, but also lacks a pure oil drive mode.
[0033] Please see Figure 4 , Figure 4 This is shown as a third schematic diagram of the architecture of a conventional hybrid power system provided in an embodiment of this application. Figure 4 As shown, the existing technology in Figure 1 An improvement was made to the hybrid power system shown, by removing the transfer case 2, introducing a clutch 7, and connecting the clutch 7 in series between the generator motor 3 and the pump set 4. Although this architecture has some function, its significance is not great.
[0034] Therefore, Figure 3 and Figure 4 The installation positions of the clutch 7 shown cannot achieve the effect that the installation position of the clutch 7 in this application can achieve.
[0035] In addition, there are many types of energy storage components for hybrid power systems. In this application, energy storage components can be replaced according to actual needs based on different energy storage components. Different energy storage components will bring different effects. If the hybrid power system uses a battery as an energy storage system, an external charging port can be added to the battery to achieve better replenishment of the battery's state of charge and further save energy.
[0036] Table 1 shows an application table for a high-capacity energy storage element.
[0037] Table 1
[0038] Please see Figure 5 , Figure 5 A flowchart illustrating a control method for a hybrid power system provided in an embodiment of this application is shown. Figure 5 The control method shown is applied to the vehicle control unit (VCU), and the VCU is connected to... Figure 2 The hybrid power system shown further includes the following methods: S100: Obtain the corresponding adjustment and control mode of the hybrid power system.
[0039] Preferably, the adjustment and control modes of the hybrid power system include intelligent control mode and manual control mode. Intelligent control means that the vehicle controller (VCU) automatically adjusts the power output of the hybrid power system according to the load demand power collected and the state of charge (SOC) corresponding to the energy storage element 6. Manual control mode means that the vehicle controller (VCU) adjusts the system according to the state of charge (SOC) corresponding to the energy storage element 6 and the operating conditions of the hybrid power system pre-entered by the driver.
[0040] If the regulation and control mode corresponding to the hybrid power system is intelligent mode, then the following will be executed: S200. Determine the current operating conditions of the hybrid power system based on the power demand of the excavator's load.
[0041] S300: Determine the target driving mode of the hybrid power system based on the current operating conditions of the hybrid power system and the state of charge of the energy storage components.
[0042] S400 controls the state of the clutch, allowing the hybrid system to output the power required by the load in the target drive mode.
[0043] If the regulation and control mode corresponding to the hybrid power system is the human-machine interaction mode, then the following will be executed: S500: Based on the pre-entered state of charge of the energy storage element and the operating conditions of the hybrid power system, determine the target drive mode of the hybrid power system.
[0044] S600 controls the state of the clutch, allowing the hybrid system to output the power required by the load in the target drive mode.
[0045] In a specific implementation, the hybrid power system of this application is applied to an excavator. In step S200, when the hybrid power system is in intelligent mode, power calculation parameters are collected in real time. For example, the power calculation parameters include, but are not limited to, at least one of the following: the vehicle's braking signal, gear signal, and throttle signal. Based on the power calculation parameters, the current load demand power of the vehicle is calculated. Then, based on the calculated load demand power, the current operating condition of the hybrid power system is determined. Furthermore, the operating condition of the hybrid power system includes, but is not limited to, at least one of the following: light load condition, medium load condition, heavy load condition, and regenerative braking condition.
[0046] In a preferred embodiment, step 200 includes: If the load demand power is less than the lower limit of the engine's efficient operating range, the current operating condition of the hybrid system is determined to be a light load condition. If the load demand power is within the engine's efficient operating range, the current operating condition of the hybrid system is determined to be a medium load condition. If the load demand power is greater than the upper limit of the engine's efficient operating range and / or the load demand power is greater than or equal to the engine's rated power, the current operating condition of the hybrid system is determined to be a heavy load condition.
[0047] In step S300, the state of charge of the energy storage element is divided into a high state of charge interval, a medium state of charge interval, and a low state of charge interval.
[0048] In another preferred embodiment, step S300 further includes: If the state of charge of the energy storage element is in the high state of charge range, it indicates that the energy storage element has sufficient power, and the target operating mode of the hybrid system is determined to be the pure electric drive mode. If the state of charge of the energy storage element is in the medium state of charge range, it indicates that the energy storage element is in a normal output state, and the target operating mode of the hybrid system is determined to be the electric main and oil auxiliary drive mode. If the state of charge of the energy storage element is in the low state of charge range, it indicates that the energy storage element cannot provide output, and the target operating mode of the hybrid system is determined according to the overall vehicle operating status.
[0049] In one specific embodiment, the step of determining the target operating mode of the hybrid power system based on the vehicle's operating state includes: If the vehicle is in operation, the target operating mode of the hybrid system is determined to be pure gasoline drive mode; if the vehicle is not in operation, the target operating mode of the hybrid system is determined to be energy storage and charging mode.
[0050] In a preferred embodiment, please refer to Figure 6 , Figure 6 This illustration shows a control flowchart of a hybrid power system under light load conditions according to an embodiment of this application. Figure 6As shown, when the hybrid system is under light load, steps S300 to S400 include: S2001. Determine the state of charge of the energy storage element.
[0051] S2002. If the state of charge of the energy storage element is in the high state of charge range, then the target operating mode of the hybrid power system is determined to be the pure electric drive mode.
[0052] S2003, Control clutch disengagement.
[0053] S2004: Turn off the engine or allow it to idle, and control the generator motor to independently output the power required by the load to drive the pump set.
[0054] S2005. If the state of charge of the energy storage element is in the medium-charge range, then the target operating mode of the hybrid power system is determined to be the electric main and oil auxiliary drive mode.
[0055] S2006, Control clutch engagement.
[0056] S2007. Control the generator motor to output main power, and control the engine to output the remaining power other than the main power to compensate for the load demand.
[0057] S2008. If the state of charge of the energy storage element is in the low state of charge range, then the working state of the whole vehicle is determined.
[0058] S2009. If the vehicle is in operation, the target operating mode of the hybrid system is determined to be pure gasoline drive mode.
[0059] S2010, Control clutch disengagement.
[0060] S2011, Control the independent output power demand of the generator motor to drive the pump group.
[0061] S2012. If the vehicle is in a non-operating state, the target operating mode of the hybrid power system is determined to be the energy storage and charging mode.
[0062] S2013, Control clutch engagement.
[0063] S2014. Control the engine to run at the optimal fuel consumption speed, drive the generator motor to generate electricity at full power, and charge the energy storage element.
[0064] In a specific example, in steps S2002 to S2004, when the hybrid system is under light load and the energy storage element is sufficiently charged, there is no need for engine 1 to intervene. The engine is shut down, clutch 7 is disengaged, and engine 1 is decoupled from generator motor, allowing the hybrid system to enter pure electric operating mode. Generator motor 3 outputs the load demand power to drive pump group 4, avoiding the idling fuel consumption of engine 1.
[0065] In steps S2005 to S2007, when the hybrid power system is under light load and the energy storage element 6 is in a medium-load state, that is, it can provide a certain output, the clutch 7 is engaged to couple the generator motor 3 with the engine 1. Specifically, the generator motor 3 is a motor driven by the energy storage element 6, and the output of the generator motor 3 is the main output, while the output of the engine 1 is the auxiliary output to compensate for the remaining power output.
[0066] In steps S2008 to S2011, when the hybrid system is under light load and the energy storage element 6 is in a low charge state range, the energy storage element 6 can no longer drive the output of the generator motor 3. At this time, combined with the vehicle's working state, the vehicle is in a working state, indicating that the hybrid system needs to provide power output to support the vehicle's operation. In this case, the clutch 7 is disengaged to decouple the generator motor 3 from the engine 1, and the engine is controlled to independently output the load demand power to drive the pump group.
[0067] In steps S2012 to S2014, when the hybrid system is under light load and the energy storage element 6 is in a low charge state range, if the vehicle is not in operation, it means that the hybrid system does not need to provide power output to the load. In this case, the energy storage element 6 needs to be charged. Specifically, the generator motor 3 is made to work in generator mode, and the clutch 7 is engaged to couple the generator motor 3 with the engine 1, and the engine 1 is controlled to drive the generator motor 3 to charge the energy storage element 6.
[0068] Please see Figure 7 , Figure 7 This illustration shows a control flowchart of a hybrid power system under medium load conditions according to an embodiment of this application. Figure 7 As shown, when the hybrid power system is under medium load conditions, steps S300 to S400 include: S3001. Determine the state of charge of the energy storage element.
[0069] S3002. If the state of charge of the energy storage element is in the high state of charge range, then the target operating mode of the hybrid power system is determined to be electric main and oil auxiliary drive mode.
[0070] S3003, Controls clutch engagement.
[0071] S3004. Control the generator motor to output main power, and control the engine to output the remaining power other than the main power to compensate for the load demand.
[0072] S3005. If the state of charge of the energy storage element is in the medium-charge range, then the target operating mode of the hybrid power system is determined to be the oil-based main drive mode with electric auxiliary drive mode.
[0073] S3006, Control clutch engagement.
[0074] S3007 controls the engine to operate in high-efficiency mode to output main torque, while the generator motor outputs auxiliary torque in electric mode, so that the engine and generator motor work together to meet the power output required by the load.
[0075] S3008. If the state of charge of the energy storage element is in the low state of charge range, then the working state of the whole vehicle is determined.
[0076] S3009. If the vehicle is in operation, the target operating mode of the hybrid system is determined to be pure gasoline drive mode.
[0077] S3010, Control clutch disengagement.
[0078] S3011, Controls the independent output power demand of the generator motor to drive the pump set.
[0079] S3012. If the vehicle is in a non-operating state, the target operating mode of the hybrid power system is determined to be the energy storage and charging mode.
[0080] S3013, Control clutch engagement.
[0081] S3014. Control the engine to run at the optimal fuel consumption speed, drive the generator motor to generate electricity at full power, and charge the energy storage element.
[0082] Under the medium load conditions provided in steps S3001 to S3014, if the actuator 5 drives the pump group 4 in the reverse direction due to inertial force, the pump group 4 drives the generator motor 3 to generate electricity and recover energy due to inertial force. In this case, when the clutch 7 is engaged, the speed of the engine 1 is stable, and the torque of the generator motor 3 is controlled within the power generation range to perform energy storage and charging mode. When the clutch 7 is disengaged, the generator motor 3 recovers energy independently, which is more efficient.
[0083] Please see Figure 8 , Figure 8 This illustration shows a control flowchart of a hybrid power system under heavy load conditions according to an embodiment of this application. Figure 8 As shown, when the hybrid power system is under heavy load, steps S300 to S400 include: S4001. Determine the state of charge of the energy storage element.
[0084] S4002. If the state of charge of the energy storage element is in the high state of charge range or the medium state of charge range, then the target operating mode of the hybrid power system is determined to be the combined full output drive mode.
[0085] S4003, Controls clutch engagement.
[0086] S4004 controls the engine to operate at rated power to output maximum continuous torque, while controlling the generator motor to provide auxiliary output at peak power.
[0087] S4005. If the state of charge of the energy storage element is in the low state of charge range, then the target operating mode of the hybrid power system is determined to be pure oil drive mode.
[0088] S4006, Control clutch disengagement.
[0089] S4007, Controls the engine's independent output load demand power to drive the pump set.
[0090] Under the heavy-load conditions provided in steps S4001 to S4007, when the boom is lowered or the vehicle is slewing braked after heavy-load operation and the inertial force is large, the engine 1 maintains a stable speed, and the generator motor 3 absorbs the huge inertial torque in the power generation mode, converting mechanical energy into electrical energy and storing it in the energy storage element 6, while avoiding excessive pressure in the hydraulic system of the pump group.
[0091] In steps S500 to S600, the vehicle controller (VCU) of this application can also be linked to the display. The energy storage element status input component and the operating condition input component are pre-designed in the relevant interface for the hybrid power system provided by the display. The driver can input the energy storage element charge state and operating condition through the energy storage element status input component and the operating condition input component, so that the vehicle controller can trigger the control of the hybrid power system based on the energy storage element charge state and operating condition input by the driver.
[0092] In this application, by providing a setting for the adjustment and control mode of the hybrid power system, the triggering method for the vehicle controller (VCU) to control the hybrid power system is actually determined. In intelligent mode, the vehicle controller is triggered to execute steps S200 to S400 by the detection event of the load demand power. In manual mode, the vehicle controller executes steps S200 to S400 by the input command issued by the driver or user regarding the operating conditions of the hybrid power system and the state of charge of the energy storage elements.
[0093] In summary, the advantages of this application are: 1. The core advantage of a hybrid system with a clutch is that the engine speed has a high degree of freedom. It can operate in the optimal speed range by decoupling the clutch, thus achieving operation in the optimal fuel consumption range, which is more energy-efficient than a hybrid system without a clutch.
[0094] 2. Engaging or disengaging the clutch can couple or decouple the power of the engine and the generator motor. When the clutch is engaged, it can achieve two modes: hybrid power or direct engine drive. When disengaged, it can achieve a range-extending mode where the engine drives the motor to charge, or a pure electric mode where the drive motor outputs power independently, making it suitable for low-emission areas.
[0095] 3. The hybrid power system provided in this application has more flexible power mode switching compared to a clutchless system, can cope with more complex working conditions, and has relatively lower generator motor power requirements, resulting in better cost.
[0096] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division; in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces; the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.
[0097] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0098] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.
[0099] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0100] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A control method for a hybrid power system, characterized in that, The hybrid power system includes an engine, a clutch, a generator motor, an energy storage element, a pump assembly, and an actuator. The engine is connected to the actuator via the clutch, the generator motor, and the pump assembly, and the energy storage element is connected to the generator motor. The method includes: Obtain the adjustment and control mode corresponding to the hybrid power system; If the adjustment and control mode corresponding to the hybrid power system is intelligent mode, then the following is executed: determine the current operating condition of the hybrid power system according to the load demand power of the excavator; Based on the current operating conditions of the hybrid power system and the state of charge of the energy storage elements, the target driving mode of the hybrid power system is determined. Control the state of the clutch so that the hybrid power system outputs the load demand power in the target drive mode.
2. The method according to claim 1, characterized in that, The step of determining the current operating condition of the hybrid power system based on the power demand of the excavator includes: If the load demand power is less than the lower limit of the engine's efficient operating range, then the current operating condition of the hybrid power system is determined to be a light load condition. If the load demand power is within the engine's high-efficiency operating range, then the current operating condition of the hybrid power system is determined to be a medium load condition. If the load demand power is greater than the upper limit of the engine's efficient operating range and / or the load demand power is greater than or equal to the engine's rated power, then the current operating condition of the hybrid power system is determined to be a heavy load condition.
3. The method according to claim 1, characterized in that, The step of determining the target driving mode of the hybrid power system based on the current operating conditions of the hybrid power system and the state of charge of the energy storage elements includes: When the hybrid power system is operating under light load, the following is executed: If the state of charge of the energy storage element is in the high state of charge range, then the target operating mode of the hybrid power system is determined to be the pure electric drive mode. If the state of charge of the energy storage element is in the medium charge range, then the target operating mode of the hybrid power system is determined to be electric main and oil auxiliary drive mode. If the state of charge of the energy storage element is in the low state of charge range, the target operating mode of the hybrid power system is determined according to the overall vehicle operating status.
4. The method according to claim 3, characterized in that, The step of determining the target operating mode of the hybrid power system based on the overall vehicle operating status includes: If the vehicle is in operation, the target operating mode of the hybrid power system is determined to be pure gasoline drive mode. If the vehicle is not in operation, the target operating mode of the hybrid power system is determined to be the energy storage and charging mode.
5. The method according to claim 1, characterized in that, The step of determining the target driving mode of the hybrid power system based on the current operating conditions of the hybrid power system and the state of charge of the energy storage elements includes: When the current operating condition of the hybrid power system is a medium load condition, perform the following: If the state of charge of the energy storage element is in the high state of charge range, then the target operating mode of the hybrid power system is determined to be electric main and oil auxiliary drive mode. If the state of charge of the energy storage element is in the medium charge range, then the target operating mode of the hybrid power system is determined to be the oil-based main drive mode with electric auxiliary drive mode. If the state of charge of the energy storage element is in the low state of charge range, the vehicle's operating state is determined. Based on the vehicle's operating state, the target operating mode of the hybrid power system is determined to be the energy storage charging mode.
6. The method according to claim 1, characterized in that, The step of determining the target driving mode of the hybrid power system based on the current operating conditions of the hybrid power system and the state of charge of the energy storage elements includes: When the current operating condition of the hybrid power system is heavy load, execute: If the state of charge of the energy storage element is in the high state of charge range or the medium state of charge range, then the target operating mode of the hybrid power system is determined to be the combined full output drive mode. If the state of charge of the energy storage element is in the low state of charge range, then the target operating mode of the hybrid power system is determined to be pure oil drive mode.
7. The method according to claim 1, characterized in that, The steps of controlling the state of the clutch to cause the hybrid power system to output the load demand power in the target drive mode include: If the target driving mode is pure electric driving mode, then the clutch is disengaged to disconnect the engine from the generator motor, causing the engine to shut off or idle, and the generator motor to independently output the power required by the load to drive the pump group. If the target drive mode is pure oil drive mode, then the clutch is disengaged to disconnect the engine from the generator motor, and the engine is controlled to independently output the power required by the load to drive the pump group.
8. The method according to claim 1, characterized in that, The step of controlling the state of the clutch to enable the hybrid system to output the load demand power in the target drive mode further includes: If the target drive mode is an electric main drive mode with hydraulic auxiliary drive mode, then control the clutch to engage, control the generator motor to output main power, and control the engine to output the remaining power other than the main power to compensate for the load demand. If the target driving mode is the energy storage and charging mode, then the clutch is controlled to engage, the engine is controlled to run at the optimal fuel consumption speed, and the generator motor is driven to generate electricity at full power to charge the energy storage element. If the target drive mode is a hydraulic main drive mode with electric auxiliary drive mode, then the clutch is controlled to engage, the engine is controlled to run in high-efficiency drive mode to output main torque, and the generator motor outputs auxiliary torque in electric mode, so that the engine and generator motor work together to meet the power output required by the load. If the target drive mode is a combined full-output drive mode, then the clutch is controlled to engage, the engine is controlled to operate at rated power to output maximum continuous torque, and the generator motor is controlled to provide auxiliary output at peak power.
9. The method according to claim 1, characterized in that, The method further includes: If the adjustment and control mode corresponding to the hybrid power system is the human-machine interaction mode, then execute: The target drive mode of the hybrid power system is determined based on the pre-entered state of charge of the energy storage element and the operating conditions of the hybrid power system. Control the state of the clutch so that the hybrid power system outputs the load demand power in the target drive mode.
10. A hybrid power system, characterized in that, The hybrid power system includes an engine, a clutch, a generator motor, an energy storage element, a pump assembly, and an actuator. The engine is connected to the actuator via the clutch, the generator motor, and the pump assembly, and the energy storage element is connected to the generator motor. The engine, clutch, generator motor, energy storage element, and pump group are all connected to the vehicle controller, which operates the control method of the hybrid power system according to any one of claims 1-9.