Extended-range power system and control method

Abstract

The invention discloses a range-extended power system and a control method, relates to the technical field of general machinery, is applied to a hybrid mowing vehicle, and comprises an energy distribution unit (10) connected with each motor controller of the mowing vehicle, and a power battery (9) and a range extender (5) which are bidirectionally connected with the energy distribution unit (10), the energy distribution unit (10) is used for controlling the power battery (9) to provide electric energy for the mowing vehicle when the discharge power and the electric quantity of the power battery (9) both meet the working requirements of the mowing vehicle; and when at least one of the discharge power and the electric quantity of the power battery (9) does not meet the working requirement of the mowing vehicle, the range extender (5) is controlled to provide electric energy for the mowing vehicle. According to the range extending type power system and the control method, energy distribution is optimized, power switching is flexible, and the efficient, energy-saving and low-noise operation effect is achieved.

Description

Technical Field

[0001] The present invention relates to the field of general mechanical technology, and in particular to an extended-range power system and a control method. Background Art

[0002] The architecture of the automobile series hybrid vehicle mainly includes the range extender, power battery, drive system, 12V body system, transmission system, AC / DC, DC / DC, 12V battery, vehicle control interface, driving information input interface, power control interface, etc. The engine in the range extender does not participate in the drive, but only drives the generator to generate electricity, resulting in large energy transmission losses, low fuel economy, and the range extender cannot start immediately and enter normal working state, and the response speed is slow.

[0003] In summary, how to effectively solve the problems of large energy transmission loss and slow response speed of the range extender is an issue that technical personnel in this field urgently need to solve. Summary of the invention

[0004] The purpose of the present invention is to provide a range-extended power system and control method, in which the range extender can directly drive the motor without passing through the power battery, thereby reducing energy transmission losses. The range extender can be started immediately and enter a normal working state, and the engine control is precise.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] An extended-range power system is applied to a hybrid lawn mower, comprising an energy distribution unit respectively connected to each motor controller of the lawn mower, a power battery and a range extender bidirectionally connected to the energy distribution unit,

[0007] The energy distribution unit is used to control the power battery to provide electrical energy to the lawn mower when both the discharge power and the power quantity of the power battery meet the working requirements of the lawn mower; and to control the range extender to provide electrical energy to the lawn mower when at least one of the discharge power and the power quantity of the power battery does not meet the working requirements of the lawn mower.

[0008] Optionally, when the discharge power and power of the power battery both meet the working requirements of the lawn mower, the power battery is controlled to provide electrical energy to the lawn mower. Specifically, when the discharge power of the power battery is greater than the working power of the lawn mower and the power of the power battery is greater than a threshold, the power battery is controlled to provide electrical energy to the lawn mower.

[0009] Optionally, when at least one of the discharge power and the power of the power battery does not meet the working requirement of the lawn mower, controlling the range extender to provide electric energy to the lawn mower comprises:

[0010] When the discharge power of the power battery is greater than the working power of the lawn mower and the power battery power is lower than a threshold, controlling the range extender to provide electric energy to the lawn mower and the power battery;

[0011] When the discharge power of the power battery is less than the working power of the lawn mower and the power level of the power battery is higher than a threshold, the range extender is controlled to provide electric energy to the lawn mower or the range extender and the power battery are controlled to provide electric energy to the lawn mower at the same time;

[0012] When the discharge power of the power battery is less than the working power of the lawn mowing operation and the power battery power is lower than a threshold, the range extender is controlled to provide power to the lawn mowing vehicle or the range extender is controlled to provide power to the lawn mowing vehicle and the power battery.

[0013] Optionally, the energy distribution unit comprises:

[0014] A high power module, used for controlling the range extender to provide electric energy to the lawn mower when the power of the power battery is lower than a threshold value and higher than a first preset value;

[0015] The low power module is used to control the range extender to provide electric energy to the lawn mower and the power battery at the same time when the power of the power battery is lower than a first preset value and higher than a second preset value.

[0016] Optionally, when the range extender and the power battery provide electrical energy to the lawn mower simultaneously, the power battery provides all the power to the lawn mower, and the range extender provides the remaining required power to the lawn mower.

[0017] Optionally, the lawn mower comprises a lawn mower device and a traveling device, a lawn mower motor controller of the lawn mower device and a driving motor controller of the traveling device are both connected to the energy distribution unit, and the energy distribution unit comprises:

[0018] A power prediction module is used to calculate the required mowing power and traveling power respectively during the operation of the mowing vehicle;

[0019] a target power module connected to the power prediction module and used to determine a target power at which the range extender provides electric energy to the lawn mower and the power battery at the same time, the target power exceeding the sum of the lawn mowing power and the walking power;

[0020] A power distribution device is connected to the target power module and is used to control the range extender to first provide electric energy to the lawn mower, and after the lawn mower is powered, the remaining electric energy is provided to the power battery for a set delay time.

[0021] Optionally, the energy distribution unit comprises:

[0022] A forced charging module, used for controlling the charging of the power battery when the power level of the power battery is lower than a low charging value when the lawn mower is in an unloaded state;

[0023] The forced power-off module is used to control the power battery to stop providing electrical energy when the power level of the power battery is lower than a power-off low value when the lawn mower is in an unloaded state.

[0024] Optionally, it further includes a battery connected to the energy distribution unit via a power conversion device, and the energy distribution unit includes:

[0025] A power detection module, used to detect the power in the battery;

[0026] The charging module is connected to the power detection module and is used to connect the power conversion device to charge the battery when the power in the battery is lower than a set value.

[0027] Optionally, when the mowing motor is working, its power is provided by the range extender and the power battery through the mowing motor controller and the energy distribution unit; when the mowing motor stops working, its residual kinetic energy is converted into electrical energy through the mowing motor controller and stored in the power battery through the energy distribution unit.

[0028] The present invention provides a control method for an extended-range power system using any one of the above, comprising the steps of:

[0029] Obtaining the discharge power of the power battery, the working power of the lawn mower, and the power of the power battery;

[0030] When the discharge power of the power battery is greater than the working power of the lawn mower, and the power of the power battery is greater than a threshold, controlling the power battery to provide electric energy to the lawn mower;

[0031] When the discharge power of the power battery is greater than the working power of the lawn mower and the power battery power is lower than a threshold, controlling the range extender to provide electric energy to the lawn mower and the power battery;

[0032] When the discharge power of the power battery is less than the working power of the lawn mower and the power level of the power battery is higher than a threshold, the range extender is controlled to provide electric energy to the lawn mower or the range extender and the power battery are controlled to provide electric energy to the lawn mower at the same time;

[0033] When the discharge power of the power battery is less than the working power of the lawn mowing operation and the power battery power is lower than a threshold, the range extender is controlled to provide power to the lawn mowing vehicle or the range extender is controlled to provide power to the lawn mowing vehicle and the power battery.

[0034] The beneficial effect of the present invention is that the extended-range power system is divided into two driving modes: pure electric mode and extended-range mode. The power battery and the range extender are both bidirectionally connected to the energy distribution unit, and the energy distribution unit is used to distribute the energy flow between the power battery and the range extender.

[0035] When the discharge power and power of the power battery can meet the working requirements of the lawn mower, the energy distribution unit controls the power battery to provide electric energy to the lawn mower. At this time, the lawn mower is completely driven by the battery.

[0036] When at least one of the discharge power or the power of the power battery does not meet the working requirements of the lawn mower, the energy distribution unit controls the range extender to start, and the range extender provides electrical energy to the lawn mower.

[0037] By applying the technical solution provided in the embodiment of the present invention, the energy distribution unit dynamically distributes the output power of the power battery and the range extender according to the charge state of the power battery and the actual power demand of the lawn mower. When the battery power is lower than the preset threshold, the range extender starts and charges the battery, while providing power for the lawn mower. The extended-range power system combines the high efficiency of pure electric drive and the endurance advantage of fuel-powered generation, optimizes energy distribution, and has flexible power switching, achieving efficient, energy-saving and low-noise operation. It is particularly suitable for lawn mowers that need to run for a long time and have limited charging conditions, and can continue to work through fuel-powered generation when the battery is low.

[0038] The present invention provides a control method for an extended-range power system using any one of the above items. Since the above-mentioned extended-range power system has the above-mentioned technical effects, the control method using the extended-range power system should also have corresponding technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A schematic diagram of an extended-range power system provided in a specific embodiment of the present invention;

[0041] Figure 2 A flow chart of a control method for applying an extended-range power system;

[0042] Figure 3 It is a schematic diagram of the water-cooled motor of the generator;

[0043] Figure 4 It is a schematic diagram of the air cooling system of the radiator;

[0044] Figure 5 The figure is a schematic diagram of the cooling device of the engine;

[0045] Figure 6 This is a schematic diagram of the range extender pressure balance device;

[0046] Figure 7 Schematic diagram of the balancing device for the generator and the engine.

[0047] Reference numerals:

[0048] 1-mowing motor; 2-battery; 3-power conversion device; 4-drive motor; 5-range extender; 6-reduction gearbox; 7-drive motor controller; 8-mowing motor controller; 9-power battery; 10-energy distribution unit; 11-generator control unit; 12-water inlet; 13-water outlet; 14-water inlet and outlet dividing parts; 15-water inlet; 16-water outlet; 17-outer water jacket; 18-O-ring; 19-inner water jacket; 20-wind guide cover; 21-fan motor; 22-impeller; 23-wind guide duct; 24-radiator; 25-speed regulating resistor; 26-crankcase; 27-crankshaft; 28-middle end cover; 29-motor chamber; 30-rotor; 31-stator; 32-rear end cover; 33-waterproof and breathable membrane; 34-oil seal; 35-flywheel; 36-fasteners. DETAILED DESCRIPTION

[0049] The core of the present invention is to provide a range-extended power system and control method. The range extender can directly drive the motor without passing through the power battery, thereby reducing energy transmission losses. The range extender should be able to start immediately and enter a normal working state, and the engine control should be precise.

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Please refer to Figure 1 , Figure 3-Figure 7 , Figure 1 A schematic diagram of an extended-range power system provided in a specific embodiment of the present invention; Figure 3 It is a schematic diagram of the water-cooled motor of the generator; Figure 4 It is a schematic diagram of the air cooling system of the radiator; Figure 5 The figure is a schematic diagram of the cooling device of the engine; Figure 6 This is a schematic diagram of the range extender pressure balance device; Figure 7 Schematic diagram of the balancing device for the generator and the engine.

[0052] In a specific embodiment, the range-extended power system provided by the present invention is applied to a hybrid lawn mower, and includes an energy distribution unit 10 respectively connected to each motor controller of the lawn mower, a power battery 9 bidirectionally connected to the energy distribution unit 10, and a range extender 5.

[0053] The energy distribution unit 10 is used to control the power battery 9 to provide electrical energy to the lawn mower when the discharge power and power of the power battery 9 meet the working requirements of the lawn mower; when at least one of the discharge power and power of the power battery 9 does not meet the working requirements of the lawn mower, control the range extender 5 to provide electrical energy to the lawn mower.

[0054] In actual applications, the extended-range power system is applied to a hybrid lawn mower, which also includes a mowing device, a traveling device, and a vehicle body. The traveling device includes a driving wheel, a reduction gear box 6, a driving motor 4, and a driving motor controller 7. The mowing device includes a blade, a mowing motor 1, and a mowing motor controller 8.

[0055] The driving motor 4 is connected to the driving wheel through the reduction box 6, and the driving motor 4 controls the rotation of the driving wheel. The driving motor controller 7 is connected to the driving motor 4, and controls the speed and forward and reverse rotation of the driving motor 4.

[0056] The mowing motor 1 is directly connected to the cutter disc to complete the mowing operation. The mowing motor controller 8 is connected to the mowing motor 1 to control the speed and rotation direction of the mowing motor 1.

[0057] The range-extended power system includes an energy distribution unit 10, a power battery 9 and a range extender 5. The range extender 5 includes an engine system, a generator system and a range extender control unit.

[0058] The engine system includes an engine assembly and an engine control unit, the generator system includes a generator assembly and a generator control unit 11 , and the range extender control unit is connected to the engine control unit and the generator control unit 11 .

[0059] The engine system is connected to the generator system, and the engine system provides mechanical power to the generator system. The generator control unit 11 converts the three-phase AC power of the generator assembly into DC power, which can supply power to the drive motor controller 7, the mowing motor controller 8, and the vehicle battery.

[0060] The power battery 9 is bidirectionally connected to the drive motor controller 7, the mowing motor controller 8, and the generator control unit 11 through the energy distribution unit 10, and can supply power to the drive motor controller 7 and the mowing motor controller 8; the charging and discharging of the power battery 9 is determined by the output power of the generator control unit 11 and the power required by the drive motor controller 7 and the mowing motor controller 8.

[0061] The extended-range power system is divided into two driving modes: pure electric mode and extended-range mode. The power battery 9 and the range extender 5 are both bidirectionally connected to the energy distribution unit 10, which is used to distribute the energy flow between the power battery 9 and the range extender 5.

[0062] When the discharge power and power of the power battery 9 can meet the working requirements of the lawn mower, the energy distribution unit 10 controls the power battery 9 to provide electric energy to the lawn mower. At this time, the lawn mower is completely driven by the battery.

[0063] When at least one of the discharge power or power of the power battery 9 does not meet the working requirements of the lawn mower, the energy distribution unit 10 controls the range extender 5 to start, and the range extender 5 provides power to the lawn mower. The range extender 5 can directly drive the motor 4 and the lawn mower motor 1 without passing through the power battery 9, and can start immediately and enter a normal working state, reducing energy transmission losses; the engine is decoupled from the transmission system, and the engine can run in the optimal area with precise control.

[0064] By applying the technical solution provided in the embodiment of the present invention, the energy distribution unit 10 dynamically distributes the output power of the power battery 9 and the range extender 5 according to the SOC (state of charge) of the power battery 9 and the actual power demand of the lawn mower. When the battery power is lower than the preset threshold, the range extender 5 starts and charges the battery, while providing power for the lawn mower. The extended-range power system combines the high efficiency of pure electric drive and the endurance advantage of fuel-powered power generation, optimizes energy distribution, and has flexible power switching, achieving efficient, energy-saving and low-noise operation. It is particularly suitable for lawn mowers that need to run for a long time and have limited charging conditions, and can continue to work through fuel-powered power generation when the battery power is insufficient.

[0065] Based on the above-mentioned specific embodiments, when the discharge power and power of the power battery 9 meet the working requirements of the lawn mower, the power battery 9 is controlled to provide electric energy to the lawn mower. Specifically, when the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is greater than the threshold, the power battery 9 is controlled to provide electric energy to the lawn mower.

[0066] In actual application, the energy distribution unit 10 monitors the SOC (state of charge) and discharge power of the power battery 9 in real time. If the discharge power and power of the power battery 9 meet the working requirements of the lawn mower, that is, the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the SOC value is greater than the preset threshold, the pure electric mode is entered, and the energy distribution unit 10 controls the power battery 9 to provide power to the lawn mower. At the same time, the energy distribution unit 10 will dynamically adjust the discharge power of the battery according to the actual power demand of the lawn mower to ensure that the battery operates within a safe range.

[0067] If the above conditions are not met, that is, the discharge power of the power battery 9 is less than the working power of the lawn mower or the SOC value of the power battery 9 is lower than the preset threshold, it switches to the extended-range mode, and the energy distribution unit 10 controls the range extender 5 to start, and the range extender 5 provides electrical energy to the lawn mower and charges the power battery 9 at the same time.

[0068] The discharge power of the power battery 9 is greater than the working power of the lawn mower, that is, the battery has sufficient power output to meet the immediate needs of the lawn mower, and the performance will not be reduced due to insufficient power.

[0069] The power of the power battery 9 is greater than a preset threshold value (such as SOC value, usually 30%-50%) to avoid continuous discharge when the battery power is too low, resulting in deep discharge of the battery and affecting the battery life. At the same time, when the power is lower than the threshold, the system will switch to the extended range mode to ensure the continuous operation of the lawn mower.

[0070] In the above embodiment, the energy distribution unit 10 dynamically switches the power source according to the battery status and working requirements to ensure the continuous operation of the lawn mower while extending the battery life.

[0071] On the basis of the above-mentioned specific embodiments, when at least one of the discharge power and the power of the power battery 9 does not meet the working requirements of the lawn mower, controlling the range extender 5 to provide electric energy to the lawn mower includes:

[0072] When the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is lower than the threshold, the range extender 5 is controlled to provide power to the lawn mower and the power battery 9;

[0073] When the discharge power of the power battery 9 is less than the working power of the lawn mower, and the power of the power battery 9 is higher than the threshold, the range extender 5 is controlled to provide power to the lawn mower, or the range extender 5 and the power battery 9 are controlled to provide power to the lawn mower at the same time;

[0074] When the discharge power of the power battery 9 is less than the working power of the mowing machine and the power of the power battery 9 is lower than a threshold, the range extender 5 is controlled to provide power to the mowing vehicle or the range extender 5 is controlled to provide power to the mowing vehicle and the power battery 9 .

[0075] In practical applications, when at least one of the discharge power and power of the power battery 9 does not meet the working requirements of the lawn mower, the energy distribution unit 10 controls the range extender 5 to provide power to the lawn mower. Specifically, there are three situations:

[0076] In the first case, the discharge power of the power battery 9 is greater than the working power of the lawn mower, but the power level of the power battery 9 is lower than the threshold. The range extender 5 is controlled to provide power to the lawn mower and the power battery 9 at the same time. At this time, the range extender provides power to the lawn mower and charges the power battery 9 at the same time to maintain the battery power level and avoid deep discharge. While ensuring the normal operation of the lawn mower, the battery life is extended.

[0077] The second situation is that the discharge power of the power battery 9 is less than the working power of the lawn mower, but the power of the power battery 9 is higher than the threshold. The range extender 5 is controlled to provide power to the lawn mower alone or the range extender 5 and the power battery 9 are controlled to provide power to the lawn mower at the same time. When the battery power is sufficient but the power is insufficient, the range extender 5 directly provides power to ensure the power demand of the lawn mower; if necessary, the power battery 9 can assist in providing part of the power to reduce the burden of the range extender 5, optimize the system efficiency, flexibly allocate the power source, and ensure the performance and efficiency of the lawn mower.

[0078] The third situation is that the discharge power of the power battery 9 is less than the working power of the lawn mower, and the power of the power battery 9 is lower than the threshold. The range extender 5 is controlled to provide power to the lawn mower alone or to provide power to the lawn mower and the power battery 9 at the same time. When both the battery power and power are insufficient, the range extender 5 gives priority to meeting the power demand of the lawn mower; at the same time, the power battery 9 is charged to maintain the continuous operation of the system, ensuring that the lawn mower can still work normally under extreme conditions, and avoiding equipment shutdown due to battery exhaustion.

[0079] In the above embodiment, the energy distribution unit 10 dynamically adjusts the distribution of the power source according to the real-time status (power and power) of the power battery 9 and the working requirements of the lawn mower. Under different working conditions, the system gives priority to meeting the power requirements of the lawn mower, while taking into account the power maintenance and charging requirements of the power battery 9. When the lawn mower requires high power output, the range extender 5 and the battery can work together to meet the instantaneous power demand. Even when the power battery 9 is low on power or power, the range extender 5 can serve as a backup power source to ensure the continuous operation of the equipment.

[0080] Based on the above specific embodiments, the energy distribution unit 10 includes:

[0081] A high power module, used to control the range extender 5 to provide power to the lawn mower when the power of the power battery 9 is lower than a threshold value and higher than a first preset value;

[0082] The low power module is used to control the range extender 5 to provide power to the lawn mower and the power battery 9 at the same time when the power of the power battery 9 is lower than a first preset value and higher than a second preset value.

[0083] In practical applications, the energy distribution unit 10 includes a high-power module and a low-power module, and these two modules respectively execute different control strategies according to the power level of the power battery 9 .

[0084] The power level of the power battery 9 is lower than the threshold (for example, the SOC threshold is 30%), but higher than the first preset value (for example, the SOC is 20%). At this time, although the power level of the power battery 9 is insufficient, there is still a certain amount of remaining power. In order to give priority to meeting the power demand of the lawn mower, the high-power module controls the range extender 5 to directly provide power to the lawn mower to ensure the normal operation of the equipment. Since the power level of the power battery 9 is still higher than the first preset value, the power battery 9 is not charged, avoiding unnecessary energy waste and battery life loss.

[0085] The power level of the power battery 9 is lower than the first preset value (for example, SOC is 20%), but higher than the second preset value (for example, SOC is 10%). At this time, the power level of the power battery 9 is low, and it is necessary to meet the power demand of the lawn mower and the charging demand of the power battery 9 at the same time. The low power module controls the range extender 5 to provide power to the lawn mower and charge the power battery 9, so as to better balance the power and power requirements and ensure the continuous operation of the equipment and the health of the battery.

[0086] In the above embodiment, through the division of labor between the high-power module and the low-power module, the energy distribution unit 10 can dynamically adjust the working mode of the range extender 5 according to the power level of the power battery 9, and manage the energy distribution more finely, which not only improves the reliability and efficiency of the system, but also extends the service life of the power battery 9. It is particularly suitable for use in lawn mowers with high requirements for reliability and endurance.

[0087] On the basis of the above-mentioned specific embodiments, when the range extender 5 and the power battery 9 provide electric energy to the lawn mower at the same time, the power battery 9 provides all the power to the lawn mower, and the range extender 5 provides the remaining required power to the lawn mower.

[0088] In actual application, when the discharge power of the power battery 9 is less than the working power of the lawn mower and the power of the power battery 9 is higher than the threshold, the range extender 5 and the power battery 9 are controlled to provide power to the lawn mower at the same time, and the power battery 9 provides all available power to the lawn mower. The range extender 5 provides the remaining required power to meet the total power demand of the lawn mower.

[0089] In the above embodiment, even when the discharge power of the battery is low, the power battery 9 can still provide part of the power, and the range extender 5 provides the remaining required power, which not only meets the power demand of the lawn mower but also optimizes the energy utilization efficiency.

[0090] On the basis of the above-mentioned specific embodiments, the lawn mower includes a lawn mower device and a traveling device, and the lawn mower motor controller 8 of the lawn mower device and the driving motor controller 7 of the traveling device are both connected to the energy distribution unit 10, and the energy distribution unit 10 includes:

[0091] The power prediction module is used to calculate the required mowing power and traveling power during the operation of the mower;

[0092] A target power module, connected to the power prediction module, is used to determine the target power of the range extender 5 to provide electric energy to the lawn mower and the power battery 9 at the same time, and the target power exceeds the sum of the mowing power and the walking power;

[0093] The power distribution device is connected to the target power module and is used to control the range extender 5 to first provide electric energy to the lawn mower, and after the lawn mower is powered, the remaining electric energy is provided to the power battery 9 for a set delay time.

[0094] In actual application, the mowing device is controlled by the mowing motor controller 8, which is responsible for the mowing operation. The walking device is controlled by the drive motor controller 7, which is responsible for the movement of the mowing vehicle. The energy distribution unit 10 connects the mowing motor controller 8 and the drive motor controller 7 for energy distribution and management. The power battery 9 provides electrical energy for the mowing vehicle. The range extender 5 provides additional electrical energy when the power battery 9 is insufficient.

[0095] The power prediction module calculates the mowing power and traveling power in real time according to the operating status of the mower (such as mowing speed, traveling speed, load condition, etc.).

[0096] The target power module calculates the total power that the range extender 5 needs to provide based on the mowing power and walking power provided by the power prediction module. Target power = mowing power + walking power + charging power. The target power exceeds the sum of the mowing power and the walking power to ensure that the system has sufficient redundant power for charging the power battery 9.

[0097] The power distribution device controls the range extender 5 to provide power to the mowing device and the traveling device in priority according to the instruction of the target power module, so as to ensure the normal operation of the mowing vehicle. After the power demand of the mowing vehicle is met, the power distribution device will delay for a set period of time (e.g., several seconds to tens of seconds), and then provide the remaining power to the power battery 9 for charging. Delayed charging can avoid frequent switching of charging states when the power demand of the mowing vehicle fluctuates, and improve the stability and reliability of the system.

[0098] In the above embodiment, when the power demand of the lawn mower changes, for example, when the power demand of the lawn mower changes greatly (such as different terrain or load conditions), the power distribution device will adjust the output power of the range extender 5 in real time, dynamically adjust the power distribution, and ensure the efficient operation of the system. By accurately calculating and dynamically allocating power, the system can optimize energy utilization efficiency and reduce energy waste. The range extender 5 gives priority to meeting the power demand of the lawn mower to ensure the continuity of the mowing operation.

[0099] Based on the above specific embodiments, the energy distribution unit 10 includes:

[0100] A forced charging module is used to control charging of the power battery 9 when the power level of the power battery 9 is lower than the charging low value when the lawn mower is in an unloaded state;

[0101] The forced power-off module is used to control the power battery 9 to stop providing power when the power level of the power battery 9 is lower than the power-off low value when the lawn mower is in an unloaded state.

[0102] In actual applications, the energy distribution unit 10 includes a forced charging module and a forced power-off module. When the lawn mower is in an unloaded state or running at a low load, that is, the lawn mower has no power demand, if the power of the power battery 9 is lower than the preset low charging value, the forced charging module will control the power battery 9 to connect to the power supply to charge the power battery 9, thereby avoiding excessive consumption of the battery power due to long-term low-load operation and extending the battery life.

[0103] By monitoring the power level of the power battery 9, when the lawn mower is in an unloaded state and the power level of the power battery 9 is lower than the preset power-off low value, the forced power-off module automatically cuts off the battery output to prevent the battery from over-discharging, thereby protecting the battery and avoiding battery damage due to deep discharge.

[0104] In the above embodiment, the forced charging and power-off modules are used to monitor the battery power and vehicle operating conditions in real time, thereby avoiding deep discharge and overcharging, and effectively extending the service life of the power battery 9.

[0105] On the basis of the above-mentioned specific embodiments, a battery 2 connected to the energy distribution unit 10 via the power conversion device 3 is also included. The energy distribution unit 10 includes:

[0106] A power detection module, used to detect the power in the battery 2;

[0107] The charging module is connected to the power detection module and is used to connect the power conversion device 3 to charge the battery 2 when the power in the battery 2 is lower than a set value.

[0108] In practical applications, the energy distribution unit 10 includes a power detection and charging module. The energy distribution unit 10 not only manages the energy distribution of the power battery 9 and the range extender 5, but is also connected to the battery 2 through the power conversion device 3 to realize power detection and charging control of the battery 2.

[0109] The power detection module monitors the power of the battery 2 in real time. Specifically, it can calculate the remaining power of the battery 2 by detecting parameters such as the voltage, current and temperature of the battery 2. The charging module is connected to the power detection module. When the power of the battery 2 is lower than the set value, the charging module is triggered to charge the battery 2 through the power conversion device 3. During the charging process, the charging module monitors the status of the battery 2 in real time to prevent overcharging or overcurrent.

[0110] The power conversion device 3 is a key component connecting the energy distribution unit 10 and the battery 2, and is used to convert the electric energy output by the power battery 9 or the range extender 5 into a voltage suitable for charging the battery 2. When the battery 2 is charging, the power is reasonably distributed to ensure the normal operation of other equipment of the lawn mower (such as the lawn mowing device and the walking device).

[0111] In the above embodiment, the power detection module can monitor the state of the battery 2 in real time and trigger charging in time. The power conversion device 3 ensures efficient use of energy during charging. The energy distribution unit 10 realizes intelligent management and efficient charging of the battery 2 according to the power of the battery 2 and the real-time needs of the lawn mower.

[0112] Based on the above-mentioned specific embodiments, when the lawn mower motor 1 is working, its power is provided by the range extender 5 and the power battery 9 through the lawn mower motor controller 8 and the energy distribution unit 10; when the lawn mower motor 1 stops working, its residual kinetic energy is converted into electrical energy through the lawn mower motor controller 8 and stored in the power battery 9 through the energy distribution unit 10.

[0113] In practical applications, the power system of the lawn mower not only realizes the distribution and management of energy, but also has the function of energy recovery.

[0114] When the mowing motor 1 is working, the power demand of the mowing motor 1 is transmitted to the energy distribution unit 10 through the mowing motor controller 8. The energy distribution unit 10 coordinates the range extender 5 and the power battery 9 to jointly provide the required electrical energy according to the actual power demand of the mowing motor 1. The power battery 9 preferentially provides part of the power to meet the immediate demand. The range extender 5 supplements the remaining power that the power battery 9 cannot meet to ensure that the power demand of the mowing motor 1 is fully met. The energy distribution unit 10 monitors the power level of the power battery 9 and the output status of the range extender 5 in real time, and dynamically adjusts the power distribution between the two to optimize the energy utilization efficiency.

[0115] When the mowing motor 1 stops working, its residual kinetic energy is converted into electrical energy through the mowing motor controller 8. The converted electrical energy is transmitted to the power battery 9 through the energy distribution unit 10 to charge the battery and realize energy recovery. The charging module in the energy distribution unit 10 can also monitor the power level and charging status of the power battery 9 to ensure the safe and efficient charging process and avoid overcharging.

[0116] It should be noted that the above embodiment is described by taking the cutter head without load as an example. Similarly, when the drive motor 4 stops working (such as decelerating or going downhill), its residual kinetic energy is converted into electrical energy through the drive motor controller 7. The converted electrical energy is transmitted to the power battery 9 through the energy distribution unit 10 to charge the battery and also realize energy recovery.

[0117] In the above embodiment, the residual kinetic energy of the mowing motor 1 and the driving motor 4 when they stop working is recovered, converted into electrical energy and stored in the power battery 9, which not only improves the energy utilization efficiency of the system but also extends the service life of the power battery 9.

[0118] like Figure 2 The present invention also provides a flow chart of a control method of an extended-range power system using any one of the above, comprising the steps of:

[0119] Obtaining the discharge power of the power battery 9, the working power of the lawn mower, and the power of the power battery 9;

[0120] When the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is greater than a threshold, the power battery 9 is controlled to provide power to the lawn mower;

[0121] When the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is lower than the threshold, the range extender 5 is controlled to provide power to the lawn mower and the power battery 9;

[0122] When the discharge power of the power battery 9 is less than the working power of the lawn mower, and the power of the power battery 9 is higher than the threshold, the range extender 5 is controlled to provide power to the lawn mower, or the range extender 5 and the power battery 9 are controlled to provide power to the lawn mower at the same time;

[0123] When the discharge power of the power battery 9 is less than the working power of the mowing machine and the power of the power battery 9 is lower than a threshold, the range extender 5 is controlled to provide power to the mowing vehicle or the range extender 5 is controlled to provide power to the mowing vehicle and the power battery 9 .

[0124] In practical applications, the control method of the range-extended power system on the lawn mower determines the working state of the power battery 9 and the range extender 5 by comparing the discharge power of the power battery 9, the working power of the lawn mower and the power of the power battery 9.

[0125] When the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is greater than the threshold, the power of the power battery 9 is sufficient, and its discharge power is sufficient to meet the working requirements of the lawn mower, so it is only necessary to let the power battery 9 provide power to the lawn mower, and the range extender 5 does not need to be started. This mode can maximize the use of battery power, save fuel or reduce the wear of the range extender 5.

[0126] When the discharge power of the power battery 9 is greater than the working power of the lawn mower, and the power of the power battery 9 is less than the threshold, although the discharge power of the power battery 9 is still greater than the working power of the lawn mower, the power is lower than the safety threshold, that is, the battery power is about to be exhausted. At this time, it is necessary to start the range extender 5 to provide power to the lawn mower and the power battery 9 at the same time to ensure the normal operation of the lawn mower, and charge the power battery 9 to avoid the equipment being shut down due to the exhaustion of the battery.

[0127] When the discharge power of the power battery 9 is less than the working power of the lawn mower, and the power of the power battery 9 is greater than the threshold, the discharge power of the power battery 9 is insufficient to meet the working requirements of the lawn mower, but the power is still within a safe range. At this time, the range extender 5 can be started to provide power to the lawn mower, or the range extender 5 and the power battery 9 can provide power to the lawn mower at the same time. The choice of this mode depends on the actual working conditions. For example, when working under high load, both can supply power at the same time to provide a more stable power output.

[0128] When the discharge power of the power battery 9 is less than the working power of the lawn mower, and the power of the power battery 9 is less than the threshold, the discharge power of the power battery 9 is insufficient and the power is lower than the threshold. At this time, the working needs of the lawn mower cannot be met by the battery alone. Therefore, the range extender 5 must be started to provide power to the lawn mower. At the same time, it is also possible to choose to let the range extender 5 provide power to the lawn mower and the power battery 9 at the same time, so as to charge the battery and extend the endurance of the device.

[0129] In the above embodiment, by real-time monitoring of the discharge power, working power and power of the power battery 9, the power supply mode is flexibly adjusted according to different workloads and battery status, and the most suitable power supply mode is selected. The intervention of the range extender 5 can provide additional power support when the battery power is insufficient, avoid over-discharge of the power battery 9, reduce the deep charge and discharge cycle of the battery, extend the battery life, and extend the cruising range of the lawn mower.

[0130] Based on the extended-range power system provided in the above embodiments, the present invention further provides a hybrid lawn mower, which includes an extended-range power system, wherein the extended-range power system is any one of the extended-range power systems in the above embodiments. Since the hybrid lawn mower adopts the extended-range power system in the above embodiments, please refer to the above embodiments for the beneficial effects of the hybrid lawn mower.

[0131] In a specific embodiment, a flow chart of a driving method of a range extender assembly applied to a hybrid lawn mower is provided, the method comprising the following steps:

[0132] S100, using the formula Calculate the power requirement of the lawn mower, where is the required power, The driving power of the lawn mower. For lawn mower mowing power, The charging and discharging power of the power battery. Other load power for lawn mower;

[0133] S110, determining a target output power of the range extender assembly according to a correspondence between the required power and the target output power;

[0134] S120, selecting the target mechanical power of the range extender assembly corresponding to the high efficiency point according to a preset target mechanical power curve corresponding to the target output power of the range extender assembly;

[0135] S130, determining a target speed and a target torque corresponding to the target mechanical power, and sending them to an engine control unit and a generator control unit;

[0136] S140, controlling the engine assembly and the generator assembly to output power according to the target speed and the target torque.

[0137] In the above embodiments, by accurately calculating the required power and optimizing the target output power, it is ensured that the operating state of the range extender assembly always matches the actual needs of the lawn mower, optimizes the operating state, reduces the mechanical loss of the engine and generator, and extends the service life of the equipment; it can dynamically adjust the output power according to different working conditions (such as driving speed, mowing load, battery status, etc.) to adapt to complex and changeable working environments. For example, in dense grass or complex terrain, the lawn mower requires higher driving power and mowing power. By dynamically adjusting the output power of the range extender assembly, it is ensured that the vehicle can operate continuously and stably. In flat terrain or sparse grass, the power demand of the lawn mower is lower. At this time, the range extender assembly can reduce the output power and reduce energy consumption.

[0138] On the basis of the above specific embodiments, the corresponding relationship between the required power and the target output power according to the formula specifically includes:

[0139] Compare the required power and the target output power,

[0140] When the battery SOC is greater than the upper threshold, the target output power is determined to be equal to the required power minus the battery discharge power.

[0141] When the battery SOC is between the lower threshold and the upper threshold, the target output power is determined to be equal to the required power;

[0142] When the battery SOC is less than the lower threshold, the target output power is determined to be equal to the required power + the charging power of the battery.

[0143] SOC refers to the state of charge of the battery, that is, the ratio of the remaining battery power to the total battery capacity, usually expressed as a percentage, and is used to guide functions such as charging, discharging and energy recovery of electric vehicles.

[0144] In the above embodiment, the battery can be ensured to operate within a safe SOC range while meeting the power requirements of the system. By adjusting the target output power, the charging and discharging process of the battery can be effectively controlled, the battery life can be extended, and the stable operation of the system can be ensured.

[0145] On the basis of the above-mentioned specific embodiments, between the preset target mechanical power curve corresponding to the target output power of the range extender assembly and the transmission to the engine control unit and the generator control unit, it also includes:

[0146] Select multiple target mechanical powers corresponding to high efficiency points as candidate target mechanical powers;

[0147] Selecting the optimal target mechanical power from a plurality of candidate target mechanical powers according to the overall performance of the lawn mower;

[0148] The optimal target speed and the optimal target torque corresponding to the optimal target mechanical power are determined and sent to the engine control unit and the generator control unit.

[0149] In a range-extended lawn mower, this control method can significantly improve the operating efficiency and comfort of the equipment. For example, under high load conditions, by optimizing the selection of target mechanical power, it can ensure that the range extender operates in the high-efficiency area while reducing noise disturbance to the operator.

[0150] After determining the optimal target mechanical power, find the corresponding optimal target speed and torque according to the preset working condition preselection table.

[0151] It should be noted that the rotor of the generator assembly is connected to the crankshaft of the engine assembly, the generator speed = engine speed, and the generator torque = engine torque.

[0152] The range extender control unit sends the optimal target speed and optimal target torque to the engine control unit and generator control unit through the vehicle's network. The control unit performs precise control based on the received instructions, adjusts the operating status of the engine and generator, ensures that the range extender operates under optimal conditions, and achieves efficient and stable energy output.

[0153] In the above embodiments, the range extender can achieve efficient, stable and low-noise operation under different working conditions, thereby improving the overall performance and user experience of the lawn mower.

[0154] Based on the above specific embodiments, after controlling the engine assembly and the generator assembly to output power according to the target speed and the target torque, the method further includes:

[0155] Detect the actual output voltage and actual output current of the generator assembly;

[0156] Receive the actual output voltage and actual output current, and use the formula Calculate the actual output power of the range extender assembly, where: is the actual output power of the range extender assembly, is the actual output voltage of the generator assembly, is the actual output current of the generator assembly;

[0157] Compare the actual output power with the target output power. When the actual output power is greater than the target output power, reduce the actual output power of the range extender assembly until it is equal to the target output power; when the actual output power is less than the target output power, increase the actual output power of the range extender assembly until it is equal to the target output power.

[0158] In the above embodiment, the actual output power is monitored in real time, and the target torque or target speed is dynamically adjusted according to the deviation between the actual output power and the target output power to implement closed-loop control, thereby ensuring that the range extender assembly always operates in a high-efficiency range and meeting the power requirements of the lawn mower.

[0159] Based on the above specific embodiments, the method for the range extender control unit to control the start of the engine assembly includes:

[0160] Combined with the current engine assembly temperature and crankshaft position, the starting target torque required for the current start is calculated;

[0161] Sending the starting target torque to the generator control unit to control the generator assembly to output torque at the starting target torque, so that the rotor of the generator assembly drives the crankshaft of the engine assembly to rotate;

[0162] The actual speed of the generator assembly is monitored and compared with the preset speed. When the actual speed reaches the preset speed, the engine assembly is controlled to start.

[0163] In the above embodiment, there is no need to equip a starter motor, and the electric starting function of the engine can be achieved through the generator system connected to the engine system, thereby reducing the structural complexity and cost of the engine.

[0164] Based on the above specific embodiments, the starting target torque is estimated based on the starting target time, the starting target speed, the friction loss torque, the pumping loss torque, and the compression loss torque. The specific method includes:

[0165] According to the formula Calculate the starting target angular velocity, where n is the starting target rotation speed;

[0166] According to the formula Calculate the starting angular acceleration, where t is the starting target time;

[0167] According to the formula Calculate the starting torque, where I is the moment of inertia;

[0168] According to the formula Calculate the starting target torque, where: is the friction loss torque, is the pump loss torque, is the compression loss torque.

[0169] Friction torque refers to the resistance caused by friction and stirring of the engine oil when the engine crankshaft and piston move;

[0170] Pump loss torque refers to the gas intake and exhaust resistance that the piston needs to overcome when the engine piston is in the intake and exhaust strokes.

[0171] Compression torque refers to the gas compression resistance that the piston needs to overcome when the engine piston is in the compression stroke;

[0172] The temperature of the engine is used to estimate the friction torque caused by the change in oil viscosity at different temperatures;

[0173] The engine crankshaft position information is used to determine the current stroke of the engine, thereby calculating the engine pump loss torque and compression torque.

[0174] In the above embodiment, the range extender control unit can accurately calculate the starting target torque and send it to the generator control unit, which can ensure that the engine can quickly and smoothly reach the target speed when starting, while reducing energy loss and mechanical shock during the starting process.

[0175] In a specific embodiment, a cooling system applied to a hybrid lawn mower includes a fan assembly installed in an engine case for cooling the engine, a radiator 24 and a cooling water pump connected to the cooling water inlet of the generator and the controller for cooling the generator and the controller, and a connecting hole is opened on the engine case; it also includes an air duct 23 with one end connected to the connecting hole and the other end facing the radiator 24.

[0176] The cooling system takes into account both water cooling and air cooling, with high heat exchange efficiency, which meets the heat dissipation requirements of the generator and controller; the amount of coolant in the water cooling system is small, the air pressure in the water cooling system is lower, the expansion kettle is reduced, and the cost is lower; the radiator 24 uses the engine's fan assembly for forced heat dissipation, and guides the cold air in the box to the radiator 24 through the air duct 23, thereby increasing the gas flow rate, enhancing the overall cooling capacity of the cooling system, and accelerating the cooling speed of the cooling system, so that the generator and the controller can reach system thermal balance during operation, prevent the generator and the controller from overheating, and extend the performance and life of the generator and the controller; the radiator 24 does not require a separate cooling fan, which reduces a separate cooling fan, has a simpler structure, and has a lower cost; reduces the failure rate of the radiator 24 failing to cool due to damage to the cooling fan; the engine's connection port has a high universality rate, which is suitable for connecting the air duct 23 to the original engine, and is easy to connect.

[0177] Based on the above specific embodiments, a flow control device is further included, which is used to adjust the opening of the air duct 23 according to the relationship that the temperature of the generator and / or the temperature of the controller is proportional to the opening of the air duct 23. The flow control device in the hybrid lawn mower dynamically adjusts the opening of the air duct 23 to control the flow of cold air acting on the radiator 24 through the air duct 23 according to the temperature changes of the generator and the controller, thereby ensuring the effective operation of the cooling system, thereby maintaining the engine, the generator and the controller at a suitable working temperature.

[0178] Based on the above specific embodiments, the flow control device includes:

[0179] a first temperature sensor for detecting a temperature of the generator;

[0180] a second temperature sensor for detecting the temperature of the controller;

[0181] The opening adjustment mechanism is installed in the air duct 23, connected to the first temperature sensor and the second temperature sensor, and is used to adjust the cross-sectional area of ​​the air duct 23 according to the relationship that the temperature of the generator and / or the temperature of the controller is proportional to the opening of the air duct 23. This adjustment mechanism ensures that the generator and the controller can operate at a suitable temperature to prevent overheating, and also improves the cooling efficiency.

[0182] Based on the above specific embodiments, a flow rate control device is also included, which is used to adjust the speed of the drive motor 4 of the fan assembly according to the relationship between the temperature of the generator and / or the temperature of the controller and the speed of the fan assembly. This adjustment mechanism ensures that the generator and the controller can operate at a suitable temperature to prevent overheating, and also improves the cooling efficiency. Combined with wind speed regulation and air volume regulation, efficient management of the cooling system of the hybrid mower is achieved, ensuring the stability and reliability of the equipment under various working conditions.

[0183] Based on the above specific embodiments, the motor speed of the fan assembly is provided with a high speed gear and a low speed gear, and the flow rate control device includes:

[0184] A speed control mechanism connected to the first temperature sensor and the second temperature sensor, and used to control the motor of the fan assembly to run at a high speed gear when the generator temperature and / or the controller temperature is higher than a set value; and to control the motor of the fan assembly to run at a low speed gear when the generator temperature and / or the controller temperature is lower than the set value.

[0185] On the basis of the above-mentioned specific embodiments, a distance adjustment device is also included, and the distance adjustment device is used to adjust the distance from the air outlet to the radiator 24 according to the relationship that the temperature of the generator and / or the temperature of the controller is inversely proportional to the distance from the air outlet of the air duct 23 to the radiator 24. That is, when the temperature of the generator and / or the temperature of the controller is higher than the preset high temperature setting value, the distance adjustment mechanism will reduce the distance from the air outlet to the radiator 24 so as to be closer to the radiator 24 and improve the cooling efficiency. When the temperature is lower than the preset low temperature setting value, the distance adjustment mechanism will increase the distance from the air outlet to the radiator 24 to reduce the cooling intensity. The distance adjustment device can automatically respond to temperature changes and quickly adjust the distance from the air outlet to the radiator 24 to keep the generator and the controller within the optimal operating temperature range, ensuring that the cooling needs of the hybrid lawn mower under different working conditions are met, while also optimizing energy efficiency.

[0186] Based on the above specific embodiments, the distance adjustment device includes:

[0187] A mobile driving mechanism connected to the first temperature sensor and the second temperature sensor, and used to drive the radiator 24 to move according to the relationship that the generator temperature and / or the controller temperature are inversely proportional to the distance from the air outlet of the air duct 23 to the radiator 24. When the generator temperature and / or the controller temperature is higher than the set value, the mobile driving mechanism will reduce the distance from the air outlet to the radiator 24 to enhance the cooling effect; when the temperature is lower than the set value, the distance from the air outlet to the radiator 24 will be increased to reduce the cooling intensity. The distance adjustment device ensures that the cooling needs of the hybrid lawn mower under different working conditions are met by intelligently adjusting the air outlet position of the air duct 23, while also optimizing energy efficiency.

[0188] In a preferred embodiment, the mobile driving mechanism includes:

[0189] A power assembly for providing power;

[0190] A transmission assembly connected to the power assembly for realizing movement of the radiator 24 .

[0191] The mobile drive mechanism provides power through the power assembly, and transmits the power to the radiator 24 through the transmission assembly to achieve its movement, and the guide mechanism ensures the accuracy of the movement. These components work together to enable the radiator 24 to dynamically adjust the distance from the air outlet of the air guide duct 23 according to the temperature changes of the generator and the controller to optimize the cooling efficiency.

[0192] Based on the above-mentioned specific embodiments, the air outlet of the air duct 23 faces the back of the radiator 24, and the air outlet surface of the air duct 23 is parallel to the back of the radiator 24. Directing the air outlet of the air duct 23 toward the back of the radiator 24 and the air outlet surface being parallel to the back of the radiator 24 can help distribute the airflow more evenly, thereby providing a consistent cooling effect on the entire surface of the radiator 24; the airflow can flow along the surface of the radiator 24, increasing the surface area of ​​contact between the air and the heat sink, thereby improving the heat exchange efficiency; space can be used more effectively, especially in a limited space, and a compact layout of the radiator 24 and the fan can be ensured while maintaining efficient heat dissipation performance.

[0193] Based on the above specific embodiments, the connection hole is opened on the engine case, facing the back of the radiator 24, which is usually where heat is concentrated. The air duct 23 is directly connected to the engine case, and at the same time, one end of the air duct 23 can face the back of the radiator 24, so that air can flow directly to cool the radiator 24.

[0194] The air duct 23 is in a straight tube shape, which simplifies the manufacturing and installation process, reduces the resistance of air flow, and improves the cooling efficiency. The straight tube shape also helps to accurately control the air flow direction, ensuring that the cooling air flows directly to the radiator 24. When the air duct 23 is a curved tube, the bending angle is not greater than 90 degrees to reduce the large wind resistance to the air flow passing through it, thereby ensuring the working efficiency of the radiator 24 device.

[0195] Based on the above-mentioned specific embodiments, the air duct 23 gradually expands outward from the connection end to the air outlet, reducing the turbulence and eddy currents of the air flow, reducing the resistance of the air flow, and improving the flow rate and uniformity of the cooling air; and providing a larger area at the air outlet to cover more parts of the radiator 24 and enhance the cooling effect.

[0196] The center of the air outlet is on the same horizontal line as the center of the radiator 24. This alignment ensures that the air coming out of the air duct 23 can flow directly and evenly over the entire surface of the radiator 24, ensuring that the cooling air flows directly to the target area. The contact area between the cold air and the radiator 24 is large, avoiding local overheating or insufficient cooling, and improving the overall performance of the hybrid lawn mower cooling system.

[0197] In a specific embodiment, the cooling device for a hybrid lawn mower provided by the present invention includes a fan motor 21, an impeller 22 mounted on the rotating shaft of the fan motor 21, the impeller 22 faces the engine to cool the engine, and also includes a temperature control mechanism for controlling the rotation speed of the fan motor 21 according to the engine temperature. The impeller 22 is separated from the engine crankshaft 27, the speed of the impeller 22 is decoupled from the engine speed, the speed of the impeller 22 does not change with the engine speed, the speed of the impeller 22 is controlled by the fan motor 21, and the fan motor 21 drives the impeller 22 to rotate to cool the engine. The fan motor 21 can adjust the gear position and control the running speed of the impeller 22 according to the engine operating conditions, temperature and other parameters to meet the cooling requirements of the engine under different operating conditions, ensure that the engine operates within the target temperature range, and optimize the problem of insufficient cooling performance caused by low fan speed when the engine is running at low speed and the problem of increased engine mechanical losses caused by excess cooling capacity. At the same time, after the engine is shut down, the fan motor 21 can continuously drive the impeller 22 to rotate and continue to provide air cooling for the engine to prevent the temperature from rising after the engine is shut down, thereby reducing energy consumption and improving engine performance and durability.

[0198] Based on the above specific embodiments, the temperature control mechanism includes:

[0199] A temperature sensor for detecting the engine operating temperature;

[0200] A temperature control unit connected to the temperature sensor, used to control the fan motor 21 to shut down or operate at a low rotation speed when the temperature sensor detects that the current operating temperature of the engine is lower than the optimal operating temperature range; when the temperature sensor detects that the current operating temperature of the engine is higher than the optimal operating temperature range, the fan motor 21 is controlled to operate at a high rotation speed. The temperature control mechanism can effectively control the temperature of the engine, keep the engine running within the optimal operating temperature range, reduce thermal stress, ensure that it can operate stably under various working conditions, and at the same time improve energy efficiency and extend the service life of the engine. By accurately controlling the rotation speed of the fan motor 21, unnecessary energy consumption can be reduced and fuel economy can be improved.

[0201] On the basis of the above-mentioned specific embodiments, the negative end of the fan motor 21 is connected to the negative pole of the power supply, and the positive end of the fan motor 21 is connected to at least two branches, one of which is a high-speed branch connected to the positive pole of the fan motor 21, and the other is a low-speed branch connected to the positive pole of the fan motor 21. The low-speed branch is connected in parallel with the high-speed branch, and a speed regulating resistor 25 is connected to the low-speed branch. The temperature control unit includes:

[0202] A branch control module connected to the low-speed branch and the high-speed branch, used to control the fan motor 21 to shut down or connect the low-speed branch when the current operating temperature of the engine is detected to be lower than the optimal operating temperature range; when the temperature sensor detects that the current operating temperature of the engine is higher than the optimal operating temperature range, control the fan motor 21 to connect the high-speed branch. An effective temperature control mechanism can be realized to automatically adjust the speed of the fan motor 21 to keep the engine running within the optimal operating temperature range.

[0203] Based on the above specific embodiments, the branch control module includes:

[0204] Relays for controlling the connection of low-speed branches and high-speed branches;

[0205] A selection component connected to the relay, used to control all relays to shut down or control the low-speed branch relay to conduct when the current operating temperature of the engine is detected to be lower than the optimal operating temperature range; when the current operating temperature of the engine is detected to be higher than the optimal operating temperature range, control the high-speed branch relay to conduct. This control method can dynamically adjust the fan cooling capacity according to the cooling requirements of the engine under different working conditions, and is easy to control.

[0206] On the basis of the above-mentioned specific embodiments, the speed regulating resistor 25 is a sliding resistor, and a curve diagram corresponding to the engine operating temperature and the effective resistance of the sliding resistor is preset in the branch selection component, and the branch selection component includes:

[0207] A resistance determination component for determining the effective resistance of the sliding resistor corresponding to the current operating temperature according to the current operating temperature of the engine and the curve graph;

[0208] A resistor driving component connected to the sliding resistor and used to drive the sliding resistor to adjust to an effective resistance position.

[0209] The resistance determination component is responsible for determining the corresponding effective resistance value of the sliding resistor according to the current operating temperature of the engine and the preset curve graph. The curve graph can be a physical diagram or a digital model stored in a microcontroller, which is used to guide the adjustment of the resistance value. The resistance drive component is connected to the sliding resistor and is responsible for driving the sliding resistor to adjust to the effective resistance position, thereby changing the resistance value. The speed regulating resistor 25 connected to the low-speed branch can be adjusted as needed, and the low-speed operation speed of the fan motor 21 can be fine-tuned by adjusting the sliding resistor to keep the engine temperature close to the optimal operating temperature range for fine temperature control.

[0210] Based on the above specific embodiments, the engine is connected with an air scoop 20, the fan motor 21 is connected to the air scoop 20, the engine crankshaft 27 is connected with a flywheel 35, and there is a gap between the end face of the impeller 22 and the end face of the flywheel 35 to avoid contact and friction during operation, which can reduce wear and energy loss, and also avoid noise caused by contact. The size of the gap needs to be precisely controlled. Too large a gap may reduce the airflow efficiency, while too small a gap may cause contact between the impeller 22 and the flywheel 35, causing damage.

[0211] Based on the above-mentioned specific embodiments, the rotating shaft of the fan motor 21 is concentric with the crankshaft 27 of the engine, and the end face of the impeller 22 is parallel to the end face of the flywheel 35, thereby reducing space occupancy and ensuring that the rotating parts of the fan motor 21 and the crankshaft 27 maintain a consistent dynamic balance during operation; it is convenient to maintain a uniform gap between the two, reduce wear caused by unbalanced operation or vibration, and can effectively manage airflow and improve cooling efficiency.

[0212] On the basis of the above-mentioned specific embodiments, the cooling device applied to the general engine further includes a gap control mechanism for controlling the gap size between the impeller 22 and the flywheel 35 according to the engine temperature. The gap control mechanism can automatically adjust the gap between the impeller 22 and the flywheel 35 according to the temperature change of the engine through the coordinated work of the power component and the transmission component, combined with the precise control of the temperature sensor and the control system, and the real-time monitoring of the feedback mechanism, so as to maintain the best performance of the engine and extend its service life.

[0213] On the basis of the above-mentioned specific embodiments, the fan motor 21 is connected to the connection hole of the air guide cover 20, the fan motor 21 is movably connected to the connection hole, and the gap control mechanism includes:

[0214] A clearance control unit connected to the temperature sensor is used to adjust the impeller 22 and the flywheel 35 to a large clearance when the current operating temperature of the engine is detected to be lower than the optimal operating temperature range; and to adjust the impeller 22 and the flywheel 35 to a small clearance when the current operating temperature of the engine is detected to be higher than the optimal operating temperature range. The clearance control mechanism can automatically adjust the clearance between the impeller 22 and the flywheel 35 according to the temperature change of the engine to maintain the optimal performance of the engine and extend its service life; this automatic adjustment mechanism helps to improve the efficiency and reliability of the engine, while reducing wear and damage caused by improper clearance.

[0215] In a specific embodiment, the water-cooled motor of a hybrid lawn mower includes an inner water jacket 19 and an outer water jacket 17 which are connected in a sleeve manner, a sealed cavity is formed between the inner water jacket 19 and the outer water jacket 17, the outer water jacket 17 is connected to a water inlet 12 and a water outlet 13 which are connected to the cavity, and a water inlet 15 and a water outlet 16 corresponding to the water inlet 12 and the water outlet 13 are provided on the outer water jacket 17; it also includes an inlet and outlet water dividing member 14 arranged in the cavity, the inlet and outlet water dividing member 14 divides the water inlet 12 and the water outlet 13 in a circumferential direction, so that after the cooling water flows into the cavity from the water inlet 12, it flows circumferentially along a side away from the inlet and outlet water dividing member 14 and flows out from the water outlet 13.

[0216] The water-cooled motor of the hybrid lawn mower provided by the present invention, the cooling water circulation of the water jacket 19 and the outer water jacket 17 of the motor, combined with the motor controller base plate for cooling by water cooling, compared with the air-cooled motor, the water-cooled motor has a higher heat dissipation efficiency, and realizes efficient cooling of the motor and its controller base plate, and can control the motor temperature within a reasonable range, keep the whole machine at a suitable working environment temperature, keep the whole machine running at a suitable working environment temperature, reduce the failure of the motor caused by high temperature, and extend the service life.

[0217] On the basis of the above-mentioned specific embodiments, the outer wall of the inner water jacket 19 has a groove, which is easy to process and maintain due to its simple structure.

[0218] The water inlet and outlet dividing piece 14 is arranged in the groove, and the two ends of the water inlet and outlet dividing piece 14 are connected to the two ends of the groove, and the top surface of the groove and the top surface of the water inlet and outlet dividing piece 14 are in contact with the inner wall of the outer water jacket 17. The axial direction of the cavity is completely blocked to prevent the coolant from flowing on both sides of the water inlet and outlet dividing piece 14, thereby ensuring the unidirectional flow of the coolant and improving the drainage guidance of the coolant. After the cooling water flows into the cavity from the water inlet nozzle 12, due to the blocking effect of the water inlet and outlet dividing piece 14, it can only flow circumferentially along the side away from the water inlet and outlet dividing piece 14. This unidirectional flow design helps to ensure uniform cooling effect of the entire motor and avoids the problem of uneven cooling effect that may be caused by the bidirectional flow of the coolant. The coolant can more effectively exchange heat when flowing through the motor because the coolant is forced to flow around the entire cavity, thereby improving the cooling efficiency and uniformity.

[0219] On the basis of the above-mentioned specific embodiments, the groove is an annular groove, and the water inlet and outlet dividing piece 14 is connected in the annular groove. Preferably, the water inlet and outlet dividing piece 14 is welded to the inner water jacket 19, and the water inlet and outlet dividing piece 14 is connected to the outer water jacket 17 through a sealing ring, which simplifies the structure of the water-cooled motor and makes processing and maintenance easier. The coordinated use of the annular groove and the water inlet and outlet dividing piece 14 reduces complex pipes and connections, and reduces manufacturing costs and maintenance difficulties.

[0220] On the basis of the above-mentioned specific embodiments, the groove is a non-through groove, and the circumferential direction of the non-through groove is blocked to form an inlet and outlet water dividing piece 14. The design of the non-through groove is relatively simple and easy to process. This structure not only improves the cooling efficiency, but also simplifies the manufacturing process and reduces the cost. Through the design of the non-through groove and the inlet and outlet water dividing piece 14, the flow efficiency and uniformity of the coolant can be improved; the two-way flow of the coolant is prevented, ensuring that the coolant can fully contact the heating part of the generator, thereby improving the cooling effect.

[0221] On the basis of the above-mentioned specific embodiments, the side of the water inlet and outlet dividing member 14 opposite to the circumference is a curved edge with concave and convex parts, such as an S-shape. The amount of coolant at the water inlet nozzle 12 and the water outlet nozzle 13 is large, and the smooth curved edge provides a smooth guiding and drainage channel for the coolant, reduces the flow resistance, prevents the coolant from gathering at the water inlet nozzle 12 and the water outlet nozzle 13, facilitates the inflow and outflow of the coolant, ensures the uniform distribution of the coolant during the flow process, and optimizes the flow characteristics of the coolant.

[0222] On the basis of the above-mentioned specific embodiments, the water inlet and outlet nozzles 13 are respectively arranged in the recesses on both side edges of the water inlet and outlet dividing member 14, which can optimize space utilization and make the entire cooling system more compact; the storage volume of the coolant in the groove can be smaller, and the recess can be used as part of the fluid dynamics optimization to reduce the formation of turbulence and eddy currents, thereby reducing the resistance of the coolant during flow, more accurately controlling the flow direction of the coolant, ensuring that the coolant flows along a predetermined path, and improving the cooling efficiency.

[0223] On the basis of the above-mentioned specific embodiments, the two sides of the water inlet and outlet dividing member 14 are of the same shape and parallel, and the cavity covers 360° of the circumferential water flow area, and the water inlet and outlet dividing member 14 is made as thin as possible. The two sides of the water inlet and outlet dividing member 14 are of the same shape and parallel, that is, the recesses on both sides are staggered in the axial direction, and the recesses on both sides have an overlapping length in the circumferential direction, and the cavity covers 360° of the circumferential water flow area, that is, the coolant flow path covers the entire circumferential area, and the coolant can contact the heat-generating components in all directions, thereby providing a uniform cooling effect, avoiding local overheating, and ensuring uniform temperature distribution of the entire component.

[0224] On the basis of the above-mentioned specific embodiments, the inner water jacket 19 is provided with grooves on both sides of the groove, and O-rings 18 are provided in the grooves to seal and connect the two ends of the inner water jacket 19 and the outer water jacket 17. The structure is compact, the assembly is simple, and the sealing is reliable; it can effectively prevent the leakage of coolant and ensure the safety and efficiency of the cooling system.

[0225] On the basis of the above-mentioned specific embodiments, a flow rate control device is further included, and the flow rate control device is used to control the water inlet flow rate at the water inlet 12 according to the relationship that the water temperature at the water outlet 13 is proportional to the water inlet flow rate at the water inlet 12. The flow rate control device can dynamically adjust the flow rate at the water inlet 12 according to the change of the water temperature at the water outlet 13, so as to achieve accurate flow rate control, maintain the required temperature conditions, and improve the efficiency and response speed of the system.

[0226] On the basis of the above-mentioned specific embodiments, a water temperature control device is further included, and the water temperature control device is used to control the temperature of the cooling water entering the water inlet 12 according to the inverse proportional relationship between the water temperature at the water outlet 13 and the temperature of the cooling water entering the water inlet 12. The water temperature control device can dynamically adjust the cooling water temperature at the water inlet 12 in response to the change of the water temperature at the water outlet 13, thereby maintaining the required temperature conditions and improving the efficiency and accuracy of the system.

[0227] In a specific embodiment, the range extender pressure balancing device of the hybrid lawn mower includes a crankcase 26 with a rear port and a motor chamber 29 with a front port, and an intermediate end cover 28 whose two end surfaces are sealed and connected to the rear port of the crankcase 26 and the front port of the motor chamber 29 respectively. The intermediate end cover 28 has a connecting hole connecting the crankcase 26 and the motor chamber 29. The crankshaft 27 in the crankcase 26 passes through the connecting hole and is connected to the rotor shaft of the motor chamber 29. The connecting hole is connected to an oil seal 34 to seal the engine oil inside the crankcase 26; and also includes a pressure balancing device for making the air pressure in the motor chamber 29 equal to the air pressure in the crankcase 26.

[0228] The crankcase 26 is designed with a ventilation system, and its internal air pressure is connected to the atmosphere, and its internal air pressure is equivalent to the atmospheric pressure. If the motor chamber 29 is in a completely sealed state, during operation, the volume of the gas in the motor chamber 29 changes due to the influence of temperature, which in turn causes a change in air pressure, which causes a pressure difference between the inside and outside of the oil seal 34, thereby destroying the working environment of the oil seal 34 and creating a risk of oil leakage. Therefore, a pressure balancing device is added to the motor chamber 29 to connect the inside of the motor chamber 29 with the outside atmosphere. When the air pressure in the motor chamber 29 is greater than the atmospheric pressure, the excess gas is discharged through the pressure balancing device. When the air pressure in the motor chamber 29 is less than the atmospheric pressure, air enters the motor chamber 29 through the pressure balancing device, balancing the air pressure inside the motor chamber 29 with the external environment, so that the air pressure in the motor chamber 29 is equivalent to the air pressure of the crankcase 26, which plays a role in protecting the oil seal 34.

[0229] In the range extender pressure balancing device provided by the present invention, the rear port of the crankcase 26 and the front port of the motor chamber 29 share an intermediate end cover 28, the front end cover of the generator is cancelled, the structure is simplified, the connection and assembly are simpler, the weight of the range extender 5 is reduced, and the cost is reduced; at the same time, on the premise of meeting the working requirements of the engine oil seal 34 and the sealing of the chambers of the generator stator 31 and the rotor 30, a pressure balancing device is added to balance the air pressure inside the motor chamber 29 and the external environment, thereby avoiding the oil leakage problem of the engine oil seal 34 caused by the change of air pressure in the motor chamber 29, and improving the performance and reliability of the range extender 5.

[0230] Based on the above specific embodiments, the pressure balancing device includes:

[0231] A pressure sensor for detecting the air pressure in the motor chamber 29;

[0232] A pressure balancing mechanism connected to the pressure sensor is used to control the connection between the outside atmosphere and the motor chamber 29 to make the outside atmospheric pressure equal to the air pressure in the motor chamber 29 when the detected air pressure in the motor chamber 29 is not equal to the atmospheric pressure.

[0233] The pressure balancing device detects the air pressure difference through a pressure sensor and controls the gas flow through a pressure balancing mechanism connected thereto. The air pressure balancing device can respond to the air pressure difference in a timely manner to keep the air pressure inside and outside the closed space of the motor chamber 29 balanced, that is, to achieve the balance of the air pressure in the motor chamber 29 and the air pressure in the crankcase 26, thereby avoiding oil leakage of the engine oil seal 34 caused by the change of air pressure in the motor chamber 29, and ensuring the safe and stable operation of the range extender 5.

[0234] Based on the above specific embodiments, the pressure balancing mechanism includes:

[0235] A calculation unit for calculating the difference between the external atmospheric pressure and the current air pressure in the motor chamber 29;

[0236] A pressure balancing unit connected to the calculation unit and used to control the ventilation direction and ventilation duration between the outside atmosphere and the motor chamber 29 according to the difference information calculated by the calculation unit.

[0237] When the air pressure in the motor chamber 29 is not equal to the external atmospheric pressure, the pressure balancing unit will control the flow direction and opening size of the valve to balance the air pressure in the motor chamber 29 with the external atmospheric pressure. The pressure balancing mechanism can accurately control the pressure balance between the motor chamber 29 and the external atmosphere through the coordinated work of the calculation unit and the pressure balancing unit to maintain the stability of the internal environment of the range extender 5 and the normal operation of the equipment.

[0238] On the basis of the above-mentioned specific embodiments, a through hole is provided on the rear end cover 32 of the motor chamber 29, and the pressure balance unit includes a waterproof and breathable membrane 33 installed at the through hole. The waterproof and breathable membrane 33 has membrane pores that can pass gas molecules and isolate liquid molecules, thereby allowing gas molecules to pass through while blocking liquid molecules, thereby achieving the dual effects of pressure balance and waterproof and breathable, ensuring that the air pressure in the motor chamber 29 is balanced with the atmospheric pressure in real time, and preventing the oil seal 34 from moving due to changes in air pressure.

[0239] On the basis of the above-mentioned specific embodiments, a shell is provided outside the waterproof breathable membrane 33, and the outer wall of the shell is provided with multiple ring grooves, and a sealing ring is provided in the ring groove. The shell and the through hole are connected through the sealing ring, thereby ensuring the sealing between the shell and the through hole, and preventing liquid and large particles from passing through the gap between the shell and the through hole;

[0240] The shell is stepped, the waterproof breathable membrane 33 is arranged at the large diameter section, the annular groove is arranged at the small diameter section, the small diameter section is inserted into the through hole and the stepped surface abuts against the end surface of the rear end cover 32, ensuring a close fit between the shell and the rear end cover 32 and enhancing the stability and sealing of the overall structure.

[0241] Based on the above-mentioned specific embodiments, the pressure balance unit includes a two-way control valve installed at the through hole, which is used to control the opening of the through hole when the detected air pressure in the motor chamber 29 is not equal to the atmospheric pressure, and the two-way control valve can pass gas molecules and isolate liquid molecules. This control valve can automatically open or close when the pressure difference exceeds a preset range, thereby adjusting the pressure balance between the motor chamber 29 and the external atmospheric pressure, and can quickly respond to pressure changes, and close the control valve after the pressure is balanced to maintain the sealing of the chamber.

[0242] In a preferred embodiment, the two-way control valve and the waterproof breathable membrane 33 can be installed in parallel at the through hole. When the air pressure in the motor chamber 29 is not equal to the external atmospheric pressure and needs to be adjusted quickly, the two-way control valve will automatically open or close according to the signal of the pressure sensor to control the inflow or outflow of gas. The two-way control valve provides a fast response capability and can quickly balance the pressure under extreme conditions. At the same time, the waterproof breathable membrane 33 provides a continuous breathable function, allowing gas molecules to pass through to maintain the pressure balance in the chamber, reduce dependence on the control valve, reduce energy consumption, and achieve more precise pressure control and protection.

[0243] The two-way control valve and the waterproof breathable membrane 33 combine active control and passive ventilation, providing an efficient, flexible and reliable pressure balance and providing a more reliable pressure balance method.

[0244] On the basis of the above-mentioned specific embodiments, a sealing detection device is also included for detecting whether the oil seal 34 moves relative to the middle end cover 28. When the sealing detection device detects that the oil seal 34 moves due to the change of the internal air pressure of the motor chamber 29, it can be repaired or replaced in time to ensure the sealing and reliability of the range extender 5.

[0245] Based on the above specific embodiments, the sealing detection device includes:

[0246] A position sensor for detecting the moving direction and moving distance of the oil seal 34 relative to the intermediate end cover 28;

[0247] A seal reset mechanism connected to the position sensor is used to control the pressure difference between the air pressure in the motor chamber 29 and the air pressure in the crankcase 26 according to the moving direction and moving distance to drive the oil seal 34 to move in the opposite direction and reset. By changing the pressure difference, a reverse force is generated, and sufficient reverse force pushes the oil seal 34 to move in the opposite direction, so that it returns to the correct position, thereby restoring the sealing performance.

[0248] In the above embodiment, the sealing detection device integrates the detection and automatic reset functions, and is mainly used to monitor and maintain the position of the oil seal 34 in the range extender 5 relative to the middle end cover 28. Through the automatic reset function, the position deviation of the oil seal 34 can be corrected in time, reducing potential failures caused by poor sealing; it can reduce manual intervention and improve the automation of the system; improve the reliability and life of the range extender 5, and reduce maintenance costs.

[0249] Based on the above specific embodiments, the sealing reset mechanism includes:

[0250] An information storage unit for storing a correspondence between a distance required for the oil seal 34 to be reset and a pressure difference between the motor chamber 29 and the crankcase 26;

[0251] A seal resetting unit connected to the information storage unit and used to control the pressure difference between the air pressure in the motor chamber 29 and the air pressure in the crankcase 26 according to the corresponding relationship between the preset moving distance and the pressure difference value to drive the oil seal 34 to move in the opposite direction and reset.

[0252] Through the automatic resetting function, the position deviation of the oil seal 34 can be corrected in time, potential failures caused by poor sealing can be reduced, and the reliability and life of the range extender 5 can be improved; manual intervention can be reduced, and the automation level of the system can be improved.

[0253] Based on the above-mentioned specific embodiments, a reminder device connected to the pressure balancing device and the sealing detection device is also included. The reminder device is used to issue an alarm when the detected air pressure in the motor chamber 29 is not equal to the atmospheric pressure or the oil seal 34 moves relative to the middle end cover 28.

[0254] The reminder device can reduce equipment failures caused by air pressure imbalance or sealing problems, improve equipment reliability and safety. Through timely reminders, potential serious problems can be avoided, reducing maintenance costs and downtime.

[0255] In a specific embodiment, a balancing device for a generator and an engine is applied to a hybrid lawn mower, wherein a crankshaft 27 of the engine is connected to a motor shaft of the generator, and includes a flywheel 35 mounted on a connecting end of the crankshaft 27 and a rotor 30 connected to the motor shaft. The motor shaft is provided with a connecting hole at one end close to the crankshaft 27, the motor shaft is concentric with the connecting hole, the connecting end of the crankshaft 27 is connected to the connecting hole, and the crankshaft 27 and the motor shaft are rigidly connected.

[0256] In the hybrid lawn mower, the connection between the engine and the generator is rigidly connected, and the flywheel 35 and the rotor 30 play the role of a "double flywheel 35". The mutual matching between the engine flywheel 35 and the generator rotor 30 fully balances the rotational inertia of the engine crankshaft 27, reduces the torque fluctuation on the engine, improves the torsion resistance between the generator and the engine, and makes the engine output torque more stable.

[0257] In addition, the motor shaft is provided with a connection hole at one end close to the crankshaft 27, and the center line of the motor shaft is in the same straight line as the center line of the connection hole, that is, the motor shaft and the crankshaft 27 are in a straight line, and the motor shaft is directly connected to the engine crankshaft 27, which ensures a high speed and torque transmission efficiency and reduces space occupation. The connecting end of the crankshaft 27 is connected to the connecting hole, that is, the crankshaft 27 and the motor shaft are connected inside the motor shaft. This design can reduce the axial space occupied by the motor shaft, make the structure more compact, and greatly improve the overall success rate density, while reducing the production cost.

[0258] On the basis of the above-mentioned specific embodiments, the connecting hole is a through hole that runs through the length of the motor shaft, and the balancing device also includes a fastener 36 connected to the other end of the connecting hole. The connecting end face of the crankshaft 27 is provided with a threaded hole, and the end of the fastener 36 is threadedly connected to the threaded hole. The head of the fastener 36 abuts against the rear end face of the motor shaft, and the rotation direction of the threaded hole is opposite to the rotation direction of the motor shaft.

[0259] In the above embodiment, the motor shaft adopts a hollow shaft, and a fastener 36 is used to realize the rigid connection between the engine crankshaft 27 and the motor shaft, and cooperates with the flywheel 35 at the front end of the crankshaft 27 to make the engine crankshaft 27 have a higher anti-torsion ability; by arranging a connecting part inside the motor shaft, the axial space occupied by the motor shaft can be reduced, making the whole device more compact; the connection method is simple, the spline and the generator connection end bearing are eliminated, the number of parts and manufacturing complexity are reduced, and the cost is reduced.

[0260] On the basis of the above-mentioned specific embodiments, the diameter of the fastener 36 is smaller than the diameter of the connecting end of the crankshaft 27, the through hole is a stepped hole including a large diameter hole and a small diameter hole, the crankshaft 27 is connected to the large diameter hole, the fastener 36 is connected to the small diameter hole, and the end of the fastener 36 is threadedly connected to the threaded hole on the end face of the crankshaft 27, which not only realizes that the fastener 36 connects the crankshaft 27 and the motor shaft, but also provides better structural stability and strength. The small diameter hole and the fastener 36 are clearance-matched to ensure the stability and safety of the fastener 36, while also meeting the requirements of assembly and operation.

[0261] On the basis of the above-mentioned specific embodiments, the large diameter hole is a tapered hole with an opening that expands outward, and the connecting end of the crankshaft 27 is a tapered shaft. The connecting end of the crankshaft 27 matches the tapered surface of the large diameter hole, and the torque transmitted by the tapered surface connection is mainly transmitted through the static friction generated by the combined pressure between the connecting surfaces, that is, the preload force of the fastener 36 transmits the torque through the friction between the matching surfaces of the tapered hole and the tapered shaft; the tapered surface matching can increase the contact area between the motor shaft and the crankshaft 27 to achieve a high-strength connection, and the matching of the motor shaft with the fastener 36 of the crankshaft 27 and the flywheel 35 has a higher anti-torsion ability; the bearing structure is eliminated at the generator connecting end, and the structure is simple.

[0262] On the basis of the above-mentioned specific embodiments, an intermediate straight hole is provided between the small-diameter hole and the tapered hole. The diameter of the intermediate straight hole is equal to the diameter of the small end of the tapered hole. The intermediate straight hole can ensure that the tapered fit is smoother and the fit accuracy is higher. When processing the tapered hole, a straight hole can be bored according to the small-end diameter and a set allowance can be left. This can eliminate the processing of the tapered hole step hole, shorten the cutting time, and improve production efficiency.

[0263] Based on the above-mentioned specific embodiments, the rear end face of the motor shaft is provided with a countersunk hole connected to the small diameter hole, and the bolt head of the fastener 36 is built into the countersunk hole. The countersunk hole can make the fastener 36 flush with the rear end face of the motor shaft or lower than the rear end face of the motor shaft. The fastener 36 is installed inside the motor shaft, reducing the protrusion on the appearance of the fastener 36, which is not only beautiful, but also improves the compactness of the assembly position.

[0264] On the basis of the above-mentioned specific embodiments, the connecting hole is an internal threaded hole, and the connecting end of the crankshaft 27 has an external thread. The connecting end of the crankshaft 27 is threadedly connected to the connecting hole, and the fastener 36 is connected to the threaded hole of the crankshaft 27 to connect the crankshaft 27 and the motor shaft, thereby realizing a double connection between the crankshaft 27 and the motor shaft, strengthening the connection strength between the motor shaft and the crankshaft 27, and having a higher anti-torsion ability.

[0265] On the basis of the above-mentioned specific embodiments, the connection hole and the connection end of the crankshaft 27 are interference-fitted, and there is a certain tightening force between the connection hole and the crankshaft 27, which can ensure the stability and load-bearing capacity of the connection. The connection end of the crankshaft 27 is threadedly connected to the connection hole, and the fastener 36 is connected to the threaded hole of the crankshaft 27 to connect the crankshaft 27 and the motor shaft, so as to realize multiple connections between the crankshaft 27 and the motor shaft, strengthen the connection strength between the motor shaft and the crankshaft 27, and have a higher anti-torsion ability.

[0266] Based on the above-mentioned specific embodiments, the connection length between the connection end of the crankshaft 27 and the connection hole accounts for one third to one half of the length of the motor shaft. The longer the connection length between the connection end of the crankshaft 27 and the connection hole, the larger the contact area can be provided, so as to more effectively transmit the torque and ensure the high efficiency of the power transmission between the generator and the crankshaft 27; the longer the connection length of the interference fit, the more contact points there are, the higher the reliability of the fit, thereby improving the overall stability of the connection; better compensation can be provided, and the fit problems caused by temperature changes can be reduced; the stiffness and strength of the connection can be increased, and the risk of deformation or damage caused by external forces can be reduced.

[0267] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0268] The hybrid lawn mower and its extended-range power system provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An extended-range power system, applied to a hybrid lawn mower, characterized in that: The invention comprises an energy distribution unit (10) respectively connected to each motor controller of the lawn mower, a power battery (9) and a range extender (5) both bidirectionally connected to the energy distribution unit (10), The energy distribution unit (10) is used to control the power battery (9) to provide electric energy to the lawn mower when both the discharge power and the power quantity of the power battery (9) meet the working requirements of the lawn mower; and to control the range extender (5) to provide electric energy to the lawn mower when at least one of the discharge power and the power quantity of the power battery (9) does not meet the working requirements of the lawn mower.

2. The extended-range power system according to claim 1, characterized in that: When the discharge power and the power level of the power battery (9) both meet the working requirements of the lawn mower, the power battery (9) is controlled to provide electric energy to the lawn mower. Specifically, when the discharge power of the power battery (9) is greater than the working power of the lawn mower and the power level of the power battery (9) is greater than a threshold, the power battery (9) is controlled to provide electric energy to the lawn mower.

3. The extended-range power system according to claim 2, characterized in that: When at least one of the discharge power and the power of the power battery (9) does not meet the working requirements of the lawn mower, controlling the range extender (5) to provide electric energy to the lawn mower comprises: When the discharge power of the power battery (9) is greater than the working power of the lawn mower, and the power level of the power battery (9) is lower than a threshold, controlling the range extender (5) to provide electric energy to the lawn mower and the power battery (9); When the discharge power of the power battery (9) is less than the working power of the lawn mower, and the power level of the power battery (9) is higher than a threshold, the range extender (5) is controlled to provide electric energy to the lawn mower, or the range extender (5) and the power battery (9) are controlled to provide electric energy to the lawn mower simultaneously; When the discharge power of the power battery (9) is less than the working power of the lawn mowing operation, and the power level of the power battery (9) is lower than a threshold value, the range extender (5) is controlled to provide electric energy to the lawn mowing vehicle, or the range extender (5) is controlled to provide electric energy to the lawn mowing vehicle and the power battery (9).

4. The extended-range power system according to claim 3, characterized in that: The energy distribution unit (10) comprises: A high power module, used for controlling the range extender (5) to provide electric energy to the lawn mower when the power level of the power battery (9) is lower than a threshold value and higher than a first preset value; A low-battery module is used to control the range extender (5) to simultaneously provide electric energy to the lawn mower and the power battery (9) when the battery level of the power battery (9) is lower than a first preset value and higher than a second preset value.

5. The extended-range power system according to claim 3, characterized in that: When the range extender (5) and the power battery (9) simultaneously provide electrical energy to the lawn mower, the power battery (9) provides all the power to the lawn mower, and the range extender (5) provides the remaining required power to the lawn mower.

6. The extended-range power system according to claim 3, characterized in that: The lawn mower comprises a lawn mower device and a traveling device, a lawn mower motor controller (8) of the lawn mower device and a drive motor controller (7) of the traveling device are both connected to the energy distribution unit (10), and the energy distribution unit (10) comprises: A power prediction module is used to calculate the required mowing power and traveling power respectively during the operation of the mowing vehicle; a target power module connected to the power prediction module and used to determine a target power at which the range extender (5) provides electric energy to the lawn mower and the power battery (9) at the same time, the target power exceeding the sum of the lawn mowing power and the walking power; A power distribution device is connected to the target power module and is used to control the range extender (5) to first provide electric energy to the lawn mower, and after the lawn mower is powered, to provide the remaining electric energy to the power battery (9) for a set delay time.

7. The extended-range power system according to claim 1, characterized in that: The energy distribution unit (10) comprises: A forced charging module, used for controlling the charging of the power battery (9) when the power level of the power battery (9) is lower than a charging low value when the lawn mower is in an unloaded state; A forced power-off module is used to control the power battery (9) to stop providing electrical energy when the power level of the power battery (9) is lower than a power-off low value when the lawn mower is in a no-load operation.

8. The extended-range power system according to claim 1, characterized in that: It also includes a battery (2) connected to the energy distribution unit (10) via a power conversion device (3), and the energy distribution unit (10) includes: A power detection module, used to detect the power level in the battery (2); A charging module is connected to the power detection module and is used to switch on the power conversion device (3) to charge the battery (2) when the power level in the battery (2) is lower than a set value.

9. The extended-range power system according to claim 1, characterized in that: When the mowing motor (1) is working, its power is provided by the range extender (5) and the power battery (9) via the mowing motor controller (8) and the energy distribution unit (10); when the mowing motor (1) stops working, its residual kinetic energy is converted into electrical energy via the mowing motor controller (8) and stored in the power battery (9) via the energy distribution unit (10).

10. A control method for an extended-range power system according to any one of claims 1 to 9, characterized in that: Includes steps: Obtaining the discharge power of the power battery (9), the operating power of the lawn mower, and the power level of the power battery (9); When the discharge power of the power battery (9) is greater than the working power of the lawn mower, and the power level of the power battery (9) is greater than a threshold, controlling the power battery (9) to provide electric energy to the lawn mower; When the discharge power of the power battery (9) is greater than the working power of the lawn mower, and the power level of the power battery (9) is lower than a threshold, controlling the range extender (5) to provide electric energy to the lawn mower and the power battery (9); When the discharge power of the power battery (9) is less than the working power of the lawn mower, and the power level of the power battery (9) is higher than a threshold, the range extender (5) is controlled to provide electric energy to the lawn mower, or the range extender (5) and the power battery (9) are controlled to provide electric energy to the lawn mower simultaneously; When the discharge power of the power battery (9) is less than the working power of the lawn mowing operation, and the power level of the power battery (9) is lower than a threshold value, the range extender (5) is controlled to provide electric energy to the lawn mowing vehicle, or the range extender (5) is controlled to provide electric energy to the lawn mowing vehicle and the power battery (9).

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