EP-4738685-A1 - ADAPTIVE CONTROL METHOD FOR ELECTRIC MOTOR LOAD, AND OUTDOOR OPERATION VEHICLE

Abstract

The present disclosure provides an adaptive control method for a load of a motor and an outdoor working vehicle. According to the control method, by pre-storing a correspondence between an operating parameter and the load of the motor, a correspondence between the operating parameter and a performance parameter of the motor, and an upper boundary threshold and a lower boundary threshold corresponding to the load, and by comparing a matching situation between a real-time operating parameter and a load parameter, the performance parameter of the motor is adjusted through straight line fitting or curve fitting to adapt to the load. Adjusting the performance parameter of the motor includes increasing/decreasing a power of the motor, increasing/decreasing a rotating speed of the motor, increasing/decreasing a current of the motor, and increasing/decreasing a torque of the motor. In this way, a problem in the related art that an output of a mowing motor of a riding mower cannot be automatically adjusted or is inaccurately adjusted is solved, improving endurance capability of an entire riding mower.

Inventors

• WANG, Haodong

Assignees

• Jiangsu Dongcheng M&E Tools Co., Ltd.

Dates

Publication Date

20260506

Application Date

20240628

Claims (20)

1. 1. An adaptive control method for a load of a motor, the method being applied to a motor control apparatus, the method comprising: collecting an operating parameter of the motor; identifying the load of the motor based on the operating parameter of the motor; and based on a correspondence between the operating parameter and the load, increasing a rotating speed of the motor in response to the operating parameter being greater than an upper boundary threshold corresponding to the load, and decreasing the rotating speed of the motor in response to the operating parameter being smaller than a lower boundary threshold corresponding to the load, wherein the method further comprises, prior to collecting the operating parameter of the motor: acquiring the correspondence between the operating parameter and the load, and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load.
2. 2. The adaptive control method for the load of the motor according to claim 1, wherein the operating parameter comprises one or all of a duty ratio, a current, and a power.
3. 3. The adaptive control method for the load of the motor according to claim 2, wherein when the operating parameter comprises the duty ratio, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a duty ratio d 0 % of the motor, and acquiring a rotating speed characteristic curve corresponding to the motor; step 20: presetting a duty ratio d 1 % and a duty ratio variable Δd of the motor, and acquiring a rotating speed characteristic curve corresponding to the motor, where d 1 =d 0 +Δd; step 30: repeating the step 20 until the duty ratio of the motor reaches 100%, and acquiring rotating speed characteristic curves corresponding to the motor under all preset duty ratios; step 40: mapping rotating speed-torque characteristic curves under different duty ratio states to a rotating speed-duty ratio coordinate system; and step 50: selecting rotating speed points or torque points under the different duty ratio states for straight line fitting or curve fitting.
4. 4. The adaptive control method for the load of the motor according to claim 2, wherein when the operating parameter comprises the duty ratio, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a rotating speed n 0 % of the motor, acquiring a rotating speed characteristic curve corresponding to the motor, and recording duty ratios under different torque scales; step 20: presetting a rotating speed n 1 % and a rotating speed variable Δn of the motor, and acquiring a rotating speed characteristic curve corresponding to the motor, where n 1 =n 0 +Δn; step 30: repeating the step 20 until the rotating speed of the motor reaches a maximum rotating speed for a no-load state, and acquiring rotating speed characteristic curves corresponding to the motor under all preset rotating speeds; step 40: mapping rotating speed-torque characteristic curves under different rotating speed states to a rotating speed-duty ratio coordinate system; and step 50: selecting rotating speed points or torque points under different duty ratio states for straight line fitting or curve fitting.
5. 5. The adaptive control method for the load of the motor according to claim 2, wherein when the operating parameter comprises the current, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a rotating speed n 0 % of the motor, and acquiring a rotating speed-torque characteristic curve and a current-torque characteristic curve corresponding to the motor; step 20: presetting a rotating speed n 1 % and a rotating speed variable Δn of the motor, and acquiring a rotating speed-torque characteristic curve and a current-torque characteristic curve corresponding to the motor, where n 1 =n 0 +Δn; step 30: repeating the step 20 until the rotating speed of the motor reaches a maximum rotating speed for a no-load state, and acquiring rotating speed-torque characteristic curves and current-torque characteristic curves corresponding to the motor under all preset rotating speeds; step 40: mapping the rotating speed-torque characteristic curves and the current-torque characteristic curves under different rotating speed states to a rotating speed-current coordinate system; and step 50: selecting rotating speed points or torque points, and current points or torque points for straight line fitting or curve fitting.
6. 6. The adaptive control method for the load of the motor according to claim 2, wherein when the operating parameter comprises the power, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a rotating speed n 0 % of the motor, and acquiring a rotating speed-torque characteristic curve and a power-torque characteristic curve corresponding to the motor; step 20: presetting a rotating speed n 1 % and a rotating speed variable Δn of the motor, and acquiring a rotating speed-torque characteristic curve and a power-torque characteristic curve corresponding to the motor, where n 1 = n 0 +Δn; step 30: repeating the step 20 until the rotating speed of the motor reaches a maximum rotating speed for a no-load state, and acquiring rotating speed-torque characteristic curves and power-torque characteristic curves corresponding to the motor under all preset rotating speeds; step 40: mapping the rotating speed-torque characteristic curves and the power-torque characteristic curves under different rotating speed states to a rotating speed-power coordinate system; and step 50: selecting rotating speed points or torque points, and power points or torque points for straight line fitting or curve fitting.
7. 7. An adaptive control method for a load of a motor, the method being applied to a motor control apparatus, the method comprising: collecting an operating parameter of the motor, the operating parameter comprising a duty ratio and/or a rotating speed; identifying the load of the motor based on the operating parameter; and based on a correspondence between the operating parameter and the load, increasing a current of the motor in response to the operating parameter being greater than an upper boundary threshold corresponding to the load, and decreasing the current of the motor in response to the operating parameter being smaller than a lower boundary threshold corresponding to the load; wherein the method further comprises, prior to collecting the operating parameter of the motor: acquiring the correspondence between the operating parameter and the load, and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load.
8. 8. The adaptive control method for the load of the motor according to claim 7, wherein when the operating parameter comprises the duty ratio, the method comprises: step 10: acquiring a correspondence between the duty ratio and the load, and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load; step 20: collecting the operating parameter of the motor, wherein the collecting the operating parameter of the motor comprises detecting a present current and acquiring a present duty ratio; step 30: preprocessing the current, and identifying the load of the motor based on the duty ratio; step 40: determining whether the motor is currently in a current adjustment process, adjusting the current by Proportional, Integral, Derivative Control (PID) and returning to the step 20 in response to determining that the motor is currently in the current adjustment process, and determining an upper boundary threshold and a lower boundary threshold corresponding to the duty ratio based on the present current and proceeding to step 50 in response to determining that the motor is not currently in the current adjustment process; step 50: determining whether the duty ratio is greater than the upper boundary threshold corresponding to the load based on the correspondence between the duty ratio and the load, increasing the current of the motor and returning to the step 20 in response to determining that the duty ratio is greater than the upper boundary threshold corresponding to the load, and proceeding to step 60 in response to determining that the duty ratio is not greater than the upper boundary threshold corresponding to the load; and step 60: determining whether the duty ratio is smaller than the lower boundary threshold corresponding to the load, decreasing the current of the motor and returning to the step 20 in response to determining that the duty ratio is smaller than the lower boundary threshold corresponding to the load, and returning to the step 20 in response to determining that the duty ratio is not smaller than the lower boundary threshold corresponding to the load.
9. 9. The adaptive control method for the load of the motor according to claim 7, wherein when the operating parameter comprises the rotating speed, the method comprises: step 10: acquiring a correspondence between the rotating speed and the load, and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load; step 20: collecting the operating parameter of the motor, wherein the collecting the operating parameter of the motor comprises detecting a present current and a rotating speed; step 30: preprocessing the current and the rotating speed, and identifying the load of the motor based on the rotating speed; step 40: determining whether the motor is currently in a current adjustment process, adjusting the current by Proportional, Integral, Derivative Control (PID) and returning to the step 20 in response to determining that the motor is currently in a current adjustment process, and determining an upper boundary threshold and a lower boundary threshold corresponding to the rotating speed based on the present current and proceeding to step 50 in response to determining that the motor is not currently in a current adjustment process; step 50: determining whether the rotating speed is greater than the upper boundary threshold corresponding to the load based on the correspondence between the rotating speed and the load, increasing the current of the motor and returning to the step 20 in response to determining that the rotating speed is greater than the upper boundary threshold corresponding to the load, and proceeding to step 60 in response to determining that the rotating speed is not greater than the upper boundary threshold corresponding to the load; and step 60: determining whether the rotating speed is smaller than the lower boundary threshold corresponding to the load, decreasing the current of the motor and returning to the step 20 in response to determining that the rotating speed is smaller than the lower boundary threshold corresponding to the load, and returning to the step 20 in response to determining that the rotating speed is not smaller than the lower boundary threshold corresponding to the load.
10. 10. The adaptive control method for the load of the motor according to claim 7, wherein when the operating parameter comprises the duty ratio, acquiring a correspondence between the duty ratio and the load of the motor and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a duty ratio d 0 % of the motor, and acquiring a current characteristic curve corresponding to the motor; step 20: presetting a duty ratio d 1 % and a duty ratio variable Δd of the motor, and acquiring a current characteristic curve corresponding to the motor, where d 1 =d 0 +Δd; step 30: repeating the step 20 until the duty ratio of the motor reaches 100%, and acquiring current characteristic curves corresponding to the motor under all preset duty ratios; step 40: mapping current-torque characteristic curves in different duty ratio states to a current-duty ratio coordinate system; and step 50: selecting current points or torque points under different duty ratio states for straight line fitting or curve fitting.
11. 11. The adaptive control method for the load of the motor according to claim 7, wherein when the operating parameter comprises the duty ratio, acquiring a correspondence between the duty ratio and the load of the motor and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a current I 0 % of the motor, acquiring a current characteristic curve corresponding to the motor, and recording duty ratios under different torque scales; step 20: presetting a current I 1 % and a duty ratio variable ΔI of the motor, and acquiring a current characteristic curve corresponding to the motor, where I 1 =I 0 +ΔI; step 30: repeating the step 20 until the motor reaches a maximum duty ratio for a no-load current, and acquiring current characteristic curves corresponding to the motor under all preset currents; step 40: mapping current-torque characteristic curves under different current states to a current-duty ratio coordinate system; and step 50: selecting current points or torque points under the different duty ratio states for straight line fitting or curve fitting.
12. 12. The adaptive control method for the load of the motor according to claim 7, wherein when the operating parameter comprising the rotating speed, acquiring a correspondence between the rotating speed and the load of the motor and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a rotating speed n 0 % of the motor, and acquiring a rotating speed-torque characteristic curve and a current-torque characteristic curve corresponding to the motor; step 20: presetting a rotating speed n 1 % and a rotating speed variable Δn of the motor, and acquiring a rotating speed-torque characteristic curve and a current-torque characteristic curve corresponding to the motor, where n 1 =n 0 +Δn; step 30: repeating step 20 until the rotating speed of the motor reaches a maximum rotating speed for a no-load state, and acquiring rotating speed-torque characteristic curves and current-torque characteristic curves corresponding to the motor under all preset rotating speeds; step 40: mapping rotating speed-torque characteristic curves and current-torque characteristic curves under different rotating speed states to a rotating speed-current coordinate system; and step 50: selecting rotating speed points or torque points, and current points or torque points for straight line fitting or curve fitting.
13. 13. An adaptive control method for a load of a motor, the method being applied to a motor control apparatus, the method comprising: acquiring an adaptive control track of the load of the motor based on an operating parameter of the motor; acquiring a correspondence between the operating parameter and the load of the motor, and acquiring an upper boundary threshold and a lower boundary threshold corresponding to the load; collecting the operating parameter of the motor; identifying the load of the motor based on the operating parameter of the motor; and based on the correspondence between the operating parameter and the load, increasing a power of the motor in response to the operating parameter being greater than the upper boundary threshold corresponding to the load, and decreasing the power of the motor in response to the operating parameter being smaller than the lower boundary threshold corresponding to the load.
14. 14. The adaptive control method for the load of the motor according to claim 13, wherein the acquiring the adaptive control track of the load of the motor based on the operating parameter of the motor comprises: selecting power points or torque points under different operating parameters, and establishing a table based on each calibrated power point or torque point; determining which grid of the table the motor falls into based on a present power and a present rotating speed of the motor, and obtaining an upper boundary threshold and a lower boundary threshold corresponding to the rotating speed after the load of the motor changes; resetting a new target power when an actual rotating speed of the motor exceeds a range formed by a preset upper boundary threshold and a preset lower boundary threshold; and transitioning an actual duty ratio onto the adaptive control track of the load by means of straight line fitting or curve fitting.
15. 15. The adaptive control method for the load of the motor according to claim 13, wherein the operating parameter comprises a duty ratio and/or a rotating speed.
16. 16. The adaptive control method for the load of the motor according to claim 15, wherein when the operating parameter comprises the duty ratio, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a duty ratio d 0 % of the motor, and acquiring a power characteristic curve corresponding to the motor; step 20: presetting a duty ratio d 1 % and a duty ratio variable Δd of the motor, and acquiring a power characteristic curve corresponding to the motor, where d 1 =d 0 +Δd; step 30: repeating the step 20 until the duty ratio of the motor reaches 100%, and acquiring power characteristic curves corresponding to the motor under all preset duty ratios; step 40: mapping power-torque characteristic curves under different duty ratio states to a power-duty ratio coordinate system; and step 50: selecting power points or torque points under the different duty ratio states for straight line fitting or curve fitting.
17. 17. The adaptive control method for the load of the motor according to claim 15, wherein when the operating parameter comprises the duty ratio, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a power P 0 % of the motor, acquiring a rotating speed characteristic curve corresponding to the motor, and recording duty ratios under different torque scales; step 20: presetting a power P 1 % and a power variable ΔP of the motor, and acquiring a power characteristic curve corresponding to the motor, where P 1 =P 0 +ΔP; step 30: repeating the step 20 until the motor reaches a maximum duty ratio for a no-load power, and acquiring power characteristic curves corresponding to the motor under all preset powers; step 40: mapping power-torque characteristic curves under different power states to a power-duty ratio coordinate system; and step 50: selecting rotating speed points or torque points under the different duty ratio states for straight line fitting or curve fitting.
18. 18. The adaptive control method for the load of the motor according to claim 15, wherein when the operating parameter comprises the rotating speed, the acquiring the correspondence between the operating parameter and the load and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load comprises: step 10: presetting a rotating speed n 0 % of the motor, and acquiring a rotating speed-torque characteristic curve and a power-torque characteristic curve corresponding to the motor; step 20: presetting a rotating speed n 1 % and a rotating speed variable Δn of the motor, and acquiring a rotating speed-torque characteristic curve and a power-torque characteristic curve corresponding to the motor, where n 1 =n 0 +Δn; step 30: repeating the step 20 until the rotating speed of the motor reaches a maximum rotating speed for a no-load state, and acquiring rotating speed-torque characteristic curves and power-torque characteristic curves corresponding to the motor under all preset rotating speeds; step 40: mapping rotating speed-torque characteristic curves and power-torque characteristic curves under different rotating speed states to a rotating speed-power coordinate system; and step 50: selecting rotating speed points or torque points, and power points or torque points for straight line fitting or curve fitting.
19. 19. An adaptive control method for a load of a motor, the method being applied to a motor control apparatus, the method comprising: collecting an operating parameter of the motor; identifying the load of the motor based on the operating parameter of the motor; and based on a correspondence between the operating parameter and the load, increasing a torque of the motor in response to the operating parameter being greater than an upper boundary threshold corresponding to the load, and decreasing the torque of the motor in response to the operating parameter being smaller than a lower boundary threshold corresponding to the load; wherein the method further comprises, prior to collecting the operating parameter of the motor: acquiring the correspondence between the operating parameter and the load, and acquiring the upper boundary threshold and the lower boundary threshold corresponding to the load.
20. 20. The adaptive control method for the load of the motor according to claim 19, wherein the operating parameter comprises a duty ratio and/or a rotating speed.

Description

FIELD The present disclosure relates to an adaptive control method for a load of a motor and an outdoor working vehicle. BACKGROUND Traditional mowers mainly include backpack mowers, handheld mowers, walk-behind mowers and the like, which feature a low degree of automation and low working efficiency, resulting in high labor intensity and a high degree of strain for a user. When addressing maintenance needs of year-round and large-area lawns, riding mowers offer advantages such as long endurance time, flexible operation, and high working efficiency, while avoiding fatigue and even work-related injuries caused by long-term working of the user. Distinguished by energy power type, present riding mowers mainly include two categories: a gasoline-powered type and a lithium-ion battery-powered type. Compared with the gasoline-powered type, the lithium-ion battery-powered type has advantages such as zero emissions, zero fuel consumption, low noise, and simple maintenance. In addition to kinetic energy consumption of driving wheels, main energy consumption of the riding mower during operation includes energy consumed by a mowing motor driving a cutting blade for mowing. Existing riding mowers generally provide the user with a plurality of adjustment gears for setting a rotating speed of the cutting blade. A higher rotating speed leads to a higher mowing efficiency, but results in a greater power and a greater energy consumption of the motor. Especially for a lithium-ion battery-powered riding mower, energy consumption of the cutting blade may affect endurance capability and a charging frequency of the riding mower. To increase a mowing area in a single traveling path, the riding mower is generally provided with one cutting blade at each of a left side and a right side under a vehicle chassis. In actual mowing operating conditions, a load of a left cutting blade is often different from a load of a right cutting blade. If control requirements for a heavy-load cutting blade are adopted for the two cutting blades, an output torque may be excessive for a light-load cutting blade, resulting in a capacity waste; if control requirements for the light-load cutting blade are adopted for the two cutting blades, the output torque may be insufficient for the heavy-load cutting blade, and some high-density grass cannot be cut smoothly. On the other hand, in the actual mowing operating conditions, growth of grass in a to-be mowed area is not necessarily uniform, with uneven density. If a gear with a relatively high rotating speed is used continuously, the capacity waste may be caused in a sparse grass area; while if a gear with a relatively low rotating speed is used, a mowing failure may be caused in a dense grass area. When the user manually switches gears, it is necessary to continuously manually determine a grass condition and an operating condition, and adjust the gears repeatedly to achieve an optimal combination between efficiency and endurance, which has high technical difficulty and complicated operations, and is prone to safety issues due to distracting the user's attention. Existing control methods also cannot accurately adjust parameters of the motor through load adaptive control to achieve adjustment of an energy output of the motor. In view of this, there is indeed a need to provide an improved adaptive control method for a load of a motor and an outdoor working vehicle to overcome defects existing in the prior art. SUMMARY Addressing defects of the related art, an objective of the present disclosure is to provide an adaptive closed-loop control method for a load of a motor, a motor control apparatus, and a working device, to automatically adjust an output to improve endurance capability. To solve problems in the related art, a technical solution adopted in the present disclosure is an adaptive closed-loop control method for a load of a motor. The control method is applied to a control apparatus of a mowing motor to achieve closed-loop control of a power, or closed-loop control of a rotating speed, or closed-loop control of a current, or closed-loop control of a torque. The control method includes: acquiring a correspondence between the load and an operating parameter of the mowing motor, and acquiring an upper boundary threshold and a lower boundary threshold corresponding to the load; collecting the operating parameter of the motor; identifying the load of the motor based on the operating parameter of the motor; and based on the correspondence between the load and the operating parameter, increasing a performance parameter of the motor in response to the operating parameter being greater than the upper boundary threshold corresponding to the load, and decreasing the performance parameter of the motor in response to the operating parameter being smaller than the lower boundary threshold corresponding to the load. Optionally, the operating parameter of the motor includes at least one of a duty ratio, a rotating speed,