Range-extending energy system and control method thereof

Abstract

The invention is suitable for the technical field of new energy, and provides a range-extending energy system and a control method thereof, and the control method comprises the steps: obtaining the electric quantity of a battery pack; when the electric quantity of the battery pack is greater than the power guarantee threshold value and less than the pure power threshold value, controlling the range extending energy system to adopt a hybrid mode; the method for controlling the extended-range energy system to adopt the hybrid mode comprises the following steps: acquiring a change trend of output power of a battery pack along with time; when the fluctuation range of the output power of the battery pack is smaller than a first threshold value, the ratio of the output power of the battery pack to the output power of the range extender is adjusted, so that the range extender works at an efficient working point; and when the fluctuation range of the output power of the battery pack is greater than a first threshold value, adjusting the output power of the range extender according to the change of the output power of the battery pack. Therefore, the power change of the external load is indirectly judged by detecting the power change of the battery pack, so that the output power of the range extender is adjusted to complement the requirement of the external load, and the working stability of the engineering machinery can be effectively ensured.

Description

Technical Field

[0001] The present invention belongs to the field of new energy technology, and in particular relates to a range-extended energy system and a control method thereof. Background Art

[0002] There are a large number of construction machinery and equipment on the market. However, at present, power supply facilities are relatively scarce in most construction areas in China. Most of them use traditional high-power diesel generator sets to provide power for outdoor construction machinery and equipment. Because traditional high-power diesel generator sets have high emissions, loud noise and high fuel consumption when generating electricity, they are not conducive to project cost control and energy conservation and environmental protection.

[0003] With the increasing development of new energy vehicles, there are range-extending solutions in which the engine and battery pack are used to drive the vehicle motor. However, the range-extending solution for new energy vehicles uses the range extender to charge the battery pack, and the battery pack drives the motor to rotate. When supplying power to various types of outdoor engineering machinery and equipment, the output of electricity from the battery pack alone is difficult to meet the high-power requirements of the engineering machinery and equipment, and the battery pack is prone to overload. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a control method for an extended-range energy system, aiming to solve the problem that in the existing control scheme of the extended-range energy system, the output of electricity from the battery pack alone is difficult to meet the high-power requirements of engineering machinery equipment, and the battery pack is easily overloaded.

[0005] The embodiment of the present application is implemented as follows: a control method for an extended-range energy system, the control method comprising: Get the power of the battery pack; When the power of the battery pack is greater than the pure electric threshold, the range-extended energy system is controlled to adopt a pure electric mode, and the battery pack supplies power to the load; When the power level of the battery pack is greater than a power conservation threshold and less than a pure power threshold, controlling the range-extended energy system to adopt a hybrid mode, wherein the power conservation threshold is less than the pure power threshold; When the power of the battery pack is less than the power conservation threshold, the range extender energy system is controlled to adopt a power conservation mode, and the range extender supplies power to the external load and the battery pack; The method for controlling the extended-range energy system to adopt a hybrid mode specifically includes: Obtain the changing trend of battery pack output power over time; When the fluctuation range of the output power of the battery pack is less than the first threshold, adjusting the output power ratio of the battery pack and the range extender so that the range extender operates at a high-efficiency operating point, wherein when operating at the high-efficiency operating point, the oil-to-electricity conversion rate of the range extender is the highest; When the fluctuation range of the output power of the battery pack is greater than a first threshold, the output power of the range extender is adjusted according to the change of the output power of the battery pack.

[0006] In a preferred embodiment of the present application, the method for adjusting the output power ratio of the battery pack and the range extender specifically includes: Obtaining the current load power, and determining whether the current load power is greater than the rated output power of the battery pack; When the current load power is greater than the rated output power of the battery pack, the target power generation range of the range extender is calculated by using the current load power and the rated output power of the battery pack, and a high-efficiency operating point is selected in the target power generation range and the range extender is operated at the high-efficiency operating point.

[0007] In a preferred embodiment of the present application, the method of selecting a high-efficiency working point in the target power generation interval and making the range extender operate at the high-efficiency working point specifically includes: By testing the engine of the range extender, a universal characteristic diagram of the engine is obtained; By testing the generator of the range extender, a first efficiency MAP diagram of the generator is obtained; The universal characteristic diagram and the first efficiency MAP diagram are superimposed to obtain a second efficiency diagram reflecting the oil-to-electricity conversion efficiency of the range extender; According to the upper and lower limits of the target power generation range, two equal power curves are obtained in the second efficiency diagram, and a high-efficiency working point with the highest efficiency is selected between the two power curves; The range extender is driven to operate according to the high-efficiency operating point.

[0008] In a preferred embodiment of the present application, the method for driving the range extender to work according to the high-efficiency working point specifically includes: Acquire a first speed and a first torque value corresponding to the high-efficiency working point in the second efficiency map; The range extender operates at the first speed and the first torque value by controlling the torque of the engine and the speed of the generator.

[0009] In a preferred embodiment of the present application, after the step of determining whether the current load power is greater than the rated output power of the battery pack, the method further includes: When the current load power is less than or equal to the rated output power of the battery pack, the battery pack supplies power to the load.

[0010] In a preferred embodiment of the present application, the method for obtaining the current load power includes: Detect battery pack power, range extender output power and high-voltage accessory power; The current load power is calculated by the following formula: ; in, Indicates the current load power. Indicates the battery pack power, Indicates the output power of the range extender, Indicates the power of high voltage accessories, , , All are scalars.

[0011] Another object of the embodiment of the present application is to provide a range-extended energy system, which is controlled and operated based on any of the control methods described above, and the system includes: Battery pack; A range extender, comprising an engine, an engine controller, a generator, and a motor controller, wherein the engine controller is connected to the engine to control the operation of the engine, the motor controller is connected to the generator to control the operation of the generator, and the rotating shaft of the generator is drivingly connected to the rotating shaft of the engine; An energy distribution unit, connected to the range extender and the battery pack via a high-voltage wiring harness, the energy distribution unit being connected to a load output port, the load output port being used to supply power to an external load; A system control unit, connected to the range extender, the battery pack and the energy distribution unit via a control bus, and used to control the range extender, the battery pack and the energy distribution unit to work in coordination; The system control unit controls the output power of the range extender according to the acquired real-time voltage and current of the DC high-voltage bus of the battery pack.

[0012] In a preferred embodiment of the present application, the range extender is connected to a water-cooled heat sink, and the battery pack is connected to a refrigeration component for dissipating heat from the battery pack and a heating component for heating the battery pack.

[0013] In a preferred embodiment of the present application, the water-cooling heat sink is connected to the heating component for heat transfer.

[0014] In a preferred embodiment of the present application, the system also includes a low-voltage unit, which includes a step-down DC converter and a battery. The step-down DC converter is used to convert the high-voltage DC power supply of the battery pack into a low-voltage DC power supply and charge the battery.

[0015] The embodiment of the present application provides a control method for a range-extended energy system. In the hybrid mode, when the fluctuation range of the battery pack output power is greater than a first threshold value, the power change of the external load is indirectly judged by detecting the power change of the battery pack, so as to control and adjust the output power of the range extender to make up for the change in demand of the external load, which can effectively ensure the stable operation of the engineering machinery and effectively prevent the battery pack from overloading the output, thereby improving the service life of the battery pack. Moreover, when the change trend of the battery pack output power tends to be stable, the output power ratio of the battery pack and the range extender is adjusted so that the range extender works at an efficient power and saves fuel. In addition, when the battery pack has a lot of power, the range-extended energy system is controlled to work in pure electric mode, which can achieve zero emissions and low noise and improve the comfort of the working environment. When the battery pack is insufficient, the range extender is used to supply power to the external load and the battery pack to improve the endurance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flow chart of a control method for a range-extended energy system provided in an embodiment of the present application; Figure 2 for Figure 1 A flow chart of a method for controlling the range-extended energy system to adopt a hybrid mode in an embodiment; Figure 3 for Figure 2 A flow chart of a method for adjusting the output power ratio of a battery pack and a range extender in an embodiment; Figure 4 for Figure 3 A flowchart of a method for selecting a high-efficiency operating point in the target power generation interval and making the range extender operate at the high-efficiency operating point in an embodiment; Figure 5 A structural block diagram of a range-extended energy system provided in an embodiment of the present application; Figure 6 A schematic diagram of a second efficiency diagram provided in an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] The specific implementation of the present application is described in detail below in conjunction with specific embodiments.

[0019] like Figure 1 As shown, a control method of a range-extended energy system provided in an embodiment of the present application is provided, and the control method includes: S110: Obtain the power of the battery pack.

[0020] In this embodiment, the range-extended energy system includes a system control unit for controlling coordinated operation of the system, and the system control unit is electrically connected to the battery pack to obtain the remaining power of the battery pack.

[0021] S120: When the power level of the battery pack is greater than the pure electric threshold, the range-extended energy system is controlled to adopt a pure electric mode, and the battery pack supplies power to the load.

[0022] In this embodiment, when the battery has a lot of power, it works in pure electric mode, where only the battery pack provides power to the load to drive the load to work, while the range extender does not work, which can achieve zero emissions and low noise, and improve the comfort of the working environment. In some embodiments, the pure electric threshold is 70% of the rated power of the battery pack.

[0023] S130: When the power level of the battery pack is greater than the power conservation threshold and less than the pure power threshold, the extended-range energy system is controlled to adopt a hybrid mode, wherein the power conservation threshold is less than the pure power threshold.

[0024] In hybrid mode, the system can switch between powering the external load solely by the battery or by the battery pack and the range extender according to the power demand of the external load, ensuring stable operation of the external load and improving economy.

[0025] like Figure 2 As shown, in some embodiments of the present application, the method of controlling the extended-range energy system to adopt a hybrid mode specifically includes: S210: Obtain the change trend of the battery pack output power over time.

[0026] In this embodiment, the output power can be obtained by calculating the product of current and voltage, and the system control unit obtains the voltage and current of the battery pack DC high-voltage bus in real time. In this way, the change trend of the battery pack output power over time can be obtained.

[0027] S220: When the fluctuation range of the output power of the battery pack is less than a first threshold, adjusting the output power ratio of the battery pack and the range extender so that the range extender operates at a high-efficiency operating point, wherein when operating at the high-efficiency operating point, the oil-to-electricity conversion efficiency of the range extender is the highest.

[0028] In some embodiments, when the fluctuation range of the output power of the battery pack is less than the first threshold, the power demand of the external load is constant. At this time, the output power of the range extender is increased, and the output power of the battery pack is reduced accordingly. Similarly, when the output power of the range extender is reduced, the output power of the battery pack will increase accordingly. Therefore, the output power of the range extender is adjusted so that the range extender works at the optimal output power. The optimal output power means that the range extender has the highest oil-to-electricity conversion rate, which can effectively save fuel consumption. It should be noted that the highest oil-to-electricity conversion rate means that the range extender can generate more electricity when consuming the same fuel. Among them, the first threshold is the power range, and the fluctuation range of the output power is less than the first threshold, which means that the output power fluctuates within the power range of the first threshold. In some embodiments, the first threshold is 0.5KW.

[0029] S230: When the fluctuation range of the output power of the battery pack is greater than a first threshold, adjusting the output power of the range extender according to the change in the output power of the battery pack.

[0030] It is understandable that when powering construction machinery, the output power of the range-extending energy system is in a state of passive change according to the needs of the external load. When the fluctuation range of the battery pack output power is greater than the first threshold, by detecting the power change of the battery pack, the power change of the external load can be indirectly reflected, so as to control and adjust the output power of the range extender to make up for the power demand change of the external load, which can effectively ensure the stable operation of the construction machinery and effectively prevent the battery pack from overloading and increasing the service life of the battery pack.

[0031] S140: When the power level of the battery pack is less than the power conservation threshold, the range extender energy system is controlled to adopt a power conservation mode, and the range extender supplies power to the external load and the battery pack.

[0032] In this embodiment, when the battery pack is low in power, the range extender operates at high power to supply power to the external load and the battery pack.

[0033] In some embodiments, when the output power of the range extender cannot meet the demand of the external load, the battery pack will change from a charging state to a discharging state to supplement the power demand of the external load. However, at this time, the battery pack mainly plays an auxiliary role and has a small output power. It will change from a discharging state to a charging state after the power of the external load decreases.

[0034] It is understandable that when the battery pack has a lot of power, controlling the range extender energy system to work in pure electric mode can achieve zero emissions and low noise, improve the comfort of the working environment, and when the battery pack is insufficient, the range extender is used to supply power to the external load and the battery pack to improve the endurance. In hybrid mode, when the fluctuation range of the battery pack output power is greater than the first threshold, the power change of the external load is indirectly judged by detecting the power change of the battery pack, so as to control and adjust the output power of the range extender to make up for the change in demand of the external load, which can effectively ensure the stable operation of the construction machinery and effectively prevent the battery pack from overloading and increasing the service life of the battery pack. In addition, when the change trend of the battery pack output power tends to be stable, the output power ratio of the battery pack and the range extender is adjusted so that the range extender works at an efficient power and saves fuel.

[0035] like Figure 3 As shown, in some embodiments of the present application, the method for adjusting the output power ratio of the battery pack and the range extender specifically includes: S310: Obtain current load power, and determine whether the current load power is greater than the rated output power of the battery pack.

[0036] In some embodiments of the present application, the method for obtaining the current load power includes: Detect battery pack power, range extender output power and high-voltage accessory power; The current load power is calculated by the following formula: ; in, Indicates the current load power. Indicates the battery pack power, Indicates the output power of the range extender, Indicates the power of high voltage accessories, , , All are scalar quantities. The high-voltage accessory power is the total power of other high-voltage power-consuming devices in the system, such as radiators and air conditioners.

[0037] It can be understood that in this embodiment, the output power of the battery tends to be stable, which indirectly reflects that the power demand of the external load tends to be stable. At this time, the range-extended energy system is in a stable working state. By detecting the battery pack power, the output power of the range extender and the power of the high-voltage accessories, the power calculation can be performed to obtain the current load power. In this way, the power change trend of the external power-consuming device can be obtained without communicating and interacting with the external power-consuming device. In this way, different power-consuming devices can be powered, and the versatility is high.

[0038] S320: When the current load power is greater than the calibrated output power of the battery pack, the target power generation range of the range extender is calculated by using the current load power and the calibrated output power of the battery pack, and a high-efficiency operating point is selected in the target power generation range to make the range extender operate at the high-efficiency operating point.

[0039] In this embodiment, the range extender is controlled to work at an efficient working point, which is specifically manifested in making the range extender work at a specific speed, torque and output power. When working at the speed, torque and output power of the efficient working point, the range extender has the highest oil-to-electricity conversion rate. It can be understood that the electric power of the external load is shared by the battery pack and the range extender. When the current load power is 50KW, the rated output power of the battery pack is 30KW, and the charging power is 10KW, at this time, the minimum power generation power of the range extender is the current load power of 50KW minus the rated output power of the battery pack of 30KW, which is equal to 20KW, and the maximum output power is the current load power of 50KW plus the charging power of the battery pack of 10KW, which is equal to 60KW. Then the target power generation power range of the range extender is 20KW-60KW.

[0040] like Figure 4 As shown, in some embodiments of the present application, the method of selecting an efficient working point in the target power generation range and making the range extender operate at the efficient working point specifically includes: S410: Obtain a universal characteristic diagram of the engine by testing the engine of the range extender.

[0041] The engine is tested on an engine bench to obtain the engine's universal characteristic diagram. The universal characteristic diagram has speed as the horizontal axis and torque as the vertical axis. The diagram is marked with fuel consumption rate contour lines and equal power curves. The coordinate points on the diagram represent the engine's operating points, which contain information on torque.

[0042] S420: Obtain a first efficiency MAP diagram of the generator by testing the generator of the range extender.

[0043] The motor is tested on a motor test bench to obtain a first efficiency MAP diagram reflecting the motor efficiency. The first efficiency MAP diagram uses the rotational speed as the horizontal axis and the torque as the vertical axis. Efficiency contour lines are marked on the diagram. The efficiency value in the first efficiency MAP is the ratio of the mechanical energy consumed by the motor to the electrical energy converted therein.

[0044] S430: Superimposing the universal characteristic diagram and the first efficiency MAP diagram of the generator to obtain a second efficiency diagram reflecting the oil-to-electricity conversion rate of the range extender.

[0045] It can be understood that the horizontal and vertical coordinates of the first efficiency MAP diagram and the universal characteristic diagram are the same, both of which use the rotational speed as the horizontal coordinate and the torque as the vertical coordinate. In this way, the two can be easily superimposed. In some embodiments, the fuel consumption rate in the universal characteristic diagram can be multiplied by the efficiency value in the first efficiency MAP diagram to obtain the efficiency value of each point in the second efficiency diagram, and this can be used to reflect the oil-to-electricity conversion rate of the range extender. By connecting the points with equal efficiency on the second efficiency diagram, efficiency contour lines can be obtained.

[0046] S440: According to the upper and lower limits of the target power generation range, two equal power curves are obtained in the second efficiency diagram, and a high-efficiency operating point with the highest efficiency is selected between the two power curves.

[0047] It can be understood that in the second efficiency diagram, the speed is the horizontal coordinate and the torque is the vertical coordinate. Each speed value and torque value corresponds to a point on the coordinate. The power value of this point can be calculated. Connecting the points whose power values ​​are equal to the upper limit of the target power generation range can obtain an equal power curve. Similarly, the equal power curve of the lower limit of the target power generation range can be obtained. The point between the two equal power curves is the point that meets the power demand. Between the two equal power curves, according to the efficiency contour lines on the second efficiency diagram, the point with the highest efficiency is found according to the peak value of the contour lines, which is the high-efficiency working point.

[0048] In some embodiments, Figure 6 As shown, it is a schematic diagram of the second efficiency diagram. For example, the target power generation range of the range extender is 20KW-60KW, and the equal power curves of 20KW and 60KW can be obtained. The most efficient A can be found between the two equal power curves, and point A in the figure is selected as the high-efficiency working point.

[0049] S450: driving the range extender to operate according to the high-efficiency operating point.

[0050] According to the target power generation range, a high-efficiency working point that meets the power requirements is selected in the second efficiency diagram, and the range extender is made to work at the high-efficiency working point. In this way, the oil-to-electricity conversion rate can be improved and the economy of power generation can be improved.

[0051] In some embodiments of the present application, the method of driving the range extender to work according to the efficient working point specifically includes: Acquire a first speed and a first torque value corresponding to the high-efficiency working point in the second efficiency map; The range extender is operated at a first speed and a first torque value by controlling the torque of the engine and the speed of the generator.

[0052] In this embodiment, the first speed and the first torque value can be obtained through the horizontal and vertical coordinates corresponding to the high-efficiency working point in the second efficiency diagram, and then the system control unit adjusts the engine torque to the first torque value through the engine controller; the system control unit adjusts the generator speed to the first speed through the generator controller. In this way, the range extender works at the high-efficiency working point, which can improve the oil-to-electricity conversion rate and improve the economy of power generation.

[0053] In some embodiments of the present application, after the step of determining whether the current load power is greater than the rated output power of the battery pack, the step further includes: When the current load power is less than or equal to the rated output power of the battery pack, the battery pack supplies power to the load.

[0054] It is understandable that when the power of the battery pack can meet the needs of the external load, using the battery pack to power the external load can use more electricity and less oil, reduce fuel consumption, and reduce noise.

[0055] Reference Figure 5 As shown, an embodiment of the present application further provides a range-extended energy system, which is controlled and operated based on the above-mentioned control method. Specifically, the system includes: a battery pack, a range extender, an energy distribution unit and a system control unit.

[0056] The battery pack may be a battery pack used in new energy vehicles, and its specific structure is common knowledge and will not be described in detail here.

[0057] The range extender includes an engine, an engine controller, a generator, and a motor controller. The engine controller is connected to the engine to control the operation of the engine, the motor controller is connected to the generator to control the operation of the generator, and the rotating shaft of the generator is drivingly connected to the rotating shaft of the engine. The engine can be a diesel engine.

[0058] The energy distribution unit is connected to the range extender and the battery pack through a high-voltage wire harness, and the energy distribution unit is connected to a load output port, and the load output port is used to supply power to an external load. In some embodiments, the energy distribution unit can be a high-voltage distribution box. The load output port is composed of two positive and negative high-voltage wire harnesses, which can output high-voltage direct current and connect to external electrical engineering machinery equipment through an interface.

[0059] The system control unit is connected to the range extender, the battery pack and the energy distribution unit through a control bus, and is used to control the range extender, the battery pack and the energy distribution unit to work in coordination.

[0060] The system control unit controls the output power of the range extender according to the acquired real-time voltage and current of the DC high-voltage bus of the battery pack.

[0061] It can be understood that the energy distribution unit connects the range extender and the battery pack through a high-voltage wiring harness, and can transmit the power of the range extender and the battery pack to the external load together to drive the external load, thereby ensuring high-power power consumption of construction machinery and equipment. In addition, the system control unit can detect the power change of the battery pack based on the acquired real-time voltage and current of the DC high-voltage bus of the battery pack, so as to indirectly judge the power change of the external load, thereby controlling and adjusting the output power of the range extender to compensate for the power demand change of the external load, which can effectively ensure the stable operation of the construction machinery and effectively prevent the battery pack from overload output, thereby improving the service life of the battery pack.

[0062] like Figure 5 As shown, in some embodiments of the present application, the range extender is connected to a water-cooled heat sink, and the battery pack is connected to a refrigeration component for dissipating heat from the battery pack and a heating component for heating the battery pack. It is understandable that the engine is cooled by the water-cooled radiator in conjunction with the engine's own crankshaft fan to ensure the normal operating temperature of the range extender during high-power power generation; the operating temperature of the battery pack is ensured by the refrigeration component and the heating component, and the range-extended energy system can also operate at different temperatures to meet different application scenarios of customers.

[0063] Specifically, in some embodiments, the heat dissipation device includes a water pump and a heat dissipation device. The water pump drives the flow of water to bring the heat of the range extender to the heat dissipation device and then dissipates the heat into the air. The heating component includes a PTC heater, which is used to heat the antifreeze and transport it to the heat exchanger on the surface of the battery pack through a pipeline for heat exchange. The refrigeration device includes an air-conditioning compressor, a condenser, and an electronic expansion valve connected in sequence by pipelines. When the temperature of the battery pack is high, the heat of the battery pack is dissipated by turning on the air-conditioning compressor, the electronic expansion valve, the condenser, and the water-cooled heat exchanger.

[0064] In some embodiments of the present application, the water-cooling heat sink is connected to the heating component for heat transfer. In this way, the water-cooling heat sink obtains heat from the range extender and brings it to the heating component to increase the temperature of the battery pack, effectively reducing energy consumption.

[0065] In some embodiments of the present application, the extended-range energy system also includes a low-voltage unit, which includes a step-down DC converter and a battery. The step-down DC converter is used to convert the high-voltage DC power supply of the battery pack into a low-voltage DC power supply and charge the battery.

[0066] In some embodiments of the present application, the extended-range energy system also includes a DC fast charging socket. The DC fast charging socket is used to connect a fast charging gun to quickly charge the battery pack when there is a fast charging pile at the construction site, thereby reducing fuel consumption and saving usage costs.

[0067] In some embodiments of the present application, the extended-range energy system also includes a human-computer interaction module, and the functions of the human-computer interaction module are mainly divided into: system parameter module, user setting module, fault handling module and factory debugging module. The system parameter module is used to display the real-time dynamic main parameter values ​​of the current system, as well as the status of the system and components, etc.; the user setting module is used to flexibly and conveniently set some display configurations for different customers, which well meets the use and needs of customers; the fault handling module is used to quickly identify faults, sound an alarm, and remind customers in time, while recording fault data and fault codes to facilitate later search for fault sources; the factory debugging module is used for the high-power integrated extended-range energy system during factory debugging and offline configuration, and the corresponding work is completed directly through the human-computer interaction touch screen without the need to connect the device.

[0068] In some embodiments of the present application, the range-extended energy system also includes a fuel tank level sensor, which provides fuel tank fuel level information to the on-site operator so that the on-site operator can add fuel in a timely manner to prevent the range extender from shutting down due to low fuel due to fuel depletion.

[0069] It should be understood that, although each step in the flow chart of each embodiment of the present application is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is clear explanation in this article, the execution of these steps does not have strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0070] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory.

[0071] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A control method for a range-extended energy system, characterized in that: The control method comprises: Get the power of the battery pack; When the power of the battery pack is greater than the pure electric threshold, the range-extended energy system is controlled to adopt a pure electric mode, and the battery pack supplies power to the load; When the power level of the battery pack is greater than a power conservation threshold and less than a pure power threshold, controlling the range-extended energy system to adopt a hybrid mode, wherein the power conservation threshold is less than the pure power threshold; When the power of the battery pack is less than the power conservation threshold, the range extender energy system is controlled to adopt a power conservation mode, and the range extender supplies power to the external load and the battery pack; The method for controlling the extended-range energy system to adopt a hybrid mode specifically includes: Obtain the changing trend of battery pack output power over time; When the fluctuation range of the output power of the battery pack is less than the first threshold, adjusting the output power ratio of the battery pack and the range extender so that the range extender operates at a high-efficiency operating point, wherein when operating at the high-efficiency operating point, the oil-to-electricity conversion rate of the range extender is the highest; When the fluctuation range of the output power of the battery pack is greater than a first threshold, the output power of the range extender is adjusted according to the change of the output power of the battery pack.

2. A control method for a range-extended energy system according to claim 1, characterized in that: The method for adjusting the output power ratio of the battery pack and the range extender specifically includes: Obtaining the current load power, and determining whether the current load power is greater than the rated output power of the battery pack; When the current load power is greater than the rated output power of the battery pack, the target power generation range of the range extender is calculated by using the current load power and the rated output power of the battery pack, and a high-efficiency operating point is selected in the target power generation range and the range extender is operated at the high-efficiency operating point.

3. A control method for a range-extended energy system according to claim 2, characterized in that: The method of selecting a high-efficiency working point in the target power generation range and making the range extender operate at the high-efficiency working point specifically includes: By testing the engine of the range extender, a universal characteristic diagram of the engine is obtained; By testing the generator of the range extender, a first efficiency MAP diagram of the generator is obtained; The universal characteristic diagram and the first efficiency MAP diagram are superimposed to obtain a second efficiency diagram reflecting the oil-to-electricity conversion efficiency of the range extender; According to the upper and lower limits of the target power generation range, two equal power curves are obtained in the second efficiency diagram, and a high-efficiency operating point with the highest efficiency is selected between the two power curves; The range extender is driven to operate according to the high-efficiency operating point.

4. A control method for a range-extended energy system according to claim 3, characterized in that: The method for driving the range extender to work according to the high-efficiency working point specifically includes: Acquire a first speed and a first torque value corresponding to the high-efficiency working point in the second efficiency map; The range extender operates at the first speed and the first torque value by controlling the torque of the engine and the speed of the generator.

5. The control method of the range-extended energy system according to claim 2, characterized in that: After the step of determining whether the current load power is greater than the rated output power of the battery pack, the method further includes: When the current load power is less than or equal to the rated output power of the battery pack, the battery pack supplies power to the load.

6. A control method for a range-extended energy system according to claim 2, characterized in that: The method for obtaining the current load power includes: Detect battery pack power, range extender output power and high-voltage accessory power; The current load power is calculated by the following formula: ； in, Indicates the current load power. Indicates the battery pack power, Indicates the output power of the range extender, Indicates the power of high voltage accessories, , , All are scalars.

7. A range-extending energy system, operated under control based on the control method according to any one of claims 1 to 6, characterized in that: The system comprises: Battery pack; A range extender, comprising an engine, an engine controller, a generator, and a motor controller, wherein the engine controller is connected to the engine to control the operation of the engine, the motor controller is connected to the generator to control the operation of the generator, and the rotating shaft of the generator is drivingly connected to the rotating shaft of the engine; An energy distribution unit, connected to the range extender and the battery pack via a high-voltage wiring harness, the energy distribution unit being connected to a load output port, the load output port being used to supply power to an external load; A system control unit, connected to the range extender, the battery pack and the energy distribution unit via a control bus, and used to control the range extender, the battery pack and the energy distribution unit to work in coordination; The system control unit controls the output power of the range extender according to the acquired real-time voltage and current of the DC high-voltage bus of the battery pack.

8. The range-extending energy system according to claim 7, characterized in that: The range extender is connected to a water-cooled heat sink, and the battery pack is connected to a refrigeration component for dissipating heat from the battery pack and a heating component for heating the battery pack.

9. The range-extending energy system according to claim 8, characterized in that: The water-cooling heat sink is connected to the heating component for heat transfer.

10. The range-extending energy system according to claim 7, characterized in that: The system also includes a low voltage unit, which includes a step-down DC converter and a battery. The step-down DC converter is used to convert the high voltage DC power supply of the battery pack into a low voltage DC power supply and charge the battery.

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