CN111756280A - Riding type mower - Google Patents

Riding type mower Download PDF

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Publication number
CN111756280A
CN111756280A CN201911389143.5A CN201911389143A CN111756280A CN 111756280 A CN111756280 A CN 111756280A CN 201911389143 A CN201911389143 A CN 201911389143A CN 111756280 A CN111756280 A CN 111756280A
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CN
China
Prior art keywords
motor
target
current
actual
torque
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201911389143.5A
Other languages
Chinese (zh)
Inventor
杨德中
代修波
甄文奇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing Chervon Industry Co Ltd
Nanjing Deshuo Industrial Co Ltd
Original Assignee
Nanjing Deshuo Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nanjing Deshuo Industrial Co Ltd filed Critical Nanjing Deshuo Industrial Co Ltd
Priority to PCT/CN2020/097063 priority Critical patent/WO2020253821A1/en
Priority to EP20827316.9A priority patent/EP3979488B1/en
Publication of CN111756280A publication Critical patent/CN111756280A/en
Priority to US17/556,049 priority patent/US11999240B2/en
Pending legal-status Critical Current

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/06—Arrangements for speed regulation of a single motor wherein the motor speed is measured and compared with a given physical value so as to adjust the motor speed
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01D—HARVESTING; MOWING
    • A01D34/00—Mowers; Mowing apparatus of harvesters
    • A01D34/006—Control or measuring arrangements
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/12—Stator flux based control involving the use of rotor position or rotor speed sensors
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
    • H02P21/18—Estimation of position or speed
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
    • H02P21/20—Estimation of torque
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/22—Current control, e.g. using a current control loop
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/04—Arrangements for controlling or regulating the speed or torque of more than one motor
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/14—Electronic commutators
    • H02P6/16—Circuit arrangements for detecting position
    • H02P6/17—Circuit arrangements for detecting position and for generating speed information
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/28—Arrangements for controlling current

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental Sciences (AREA)
  • Harvester Elements (AREA)

Abstract

The invention discloses a riding mower, comprising: the power output device comprises a walking assembly, a power output assembly, a power supply device, a driving circuit, an operating device and a control module, wherein the walking assembly comprises a walking wheel and a first motor for driving the walking wheel to walk, the operating device is used for setting at least one of target torque and target rotating speed of the first motor, the control module is used for outputting a control signal to the driving circuit to enable input current or input voltage of the first motor to change along with position change of a rotor of the first motor, actual torque of the first motor reaches or basically reaches the target torque within first preset time, and the first preset time is less than 100 ms. The riding type mower can achieve higher response speed of the motor driving the travelling wheels to travel, and is good in user operation experience and safety.

Description

Riding type mower
Technical Field
The present invention relates to riding mowers.
Background
At present, riding lawn mowers or riding lawn mowers are popular in golf courses or greens with large areas, users can sit on the riding lawn mowers and freely control the arbitrary advancing direction of the lawn mowers to mow by controlling an operating rod, and compared with a hand-push type lawn mower to mow, the riding lawn mow saves much labor.
The user can set the target speed of the motor of the driving travelling wheel by pushing the operating device, the control unit can acquire the target speed, and then outputs a control signal to the first motor of the driving travelling wheel according to the target rotating speed so as to output torque to the travelling wheel, so that the driving travelling wheel travels at the set target speed. However, in the conventional motor control method, hysteresis exists, the torque response speed of the motor is slow, the motor may not reach the target speed set by the operating device within a preset time, and the operator may make a misjudgment to cause the riding mower to jump during walking, so that the user experience is poor, and when the torque response speed of the motor exceeds the range of 100ms to 200ms, the operator can obviously feel that the torque response speed of the motor is slow. Further, since the torque response speed of the motor is low, the riding mower may be moved by an erroneous operation due to an erroneous judgment by an operator, and the mower may slip backward due to a delay in response of the motor during climbing of the lawn mower.
In the riding mower, it is desired that the torque response speed of the first motor is increased after the target rotation speed and the target torque of the motor are set by the operating device, so that the first motor can stably and quickly reach the target rotation speed, and the user experience is enhanced. In the traditional control system, the torque response speed of the motor is low, the target rotating speed and the target torque cannot be reached in a short time, so that the user experience is poor, and the safety risk exists.
Disclosure of Invention
To overcome the deficiencies of the prior art, it is a primary object of the present invention to provide a riding mower with faster motor response speed.
In order to achieve the purpose, the invention adopts the following technical scheme:
a riding lawn mower comprising: the walking assembly comprises a walking wheel and a first motor for driving the walking wheel to walk, and the first motor comprises a stator and a rotor; a power take off assembly including a blade for mowing and a second motor driving the blade; a power supply device at least for supplying electric energy to the first motor; a drive circuit for loading electric energy of the power supply device to the first motor; an operating device for setting at least one of a target torque and a target rotational speed of the first motor; and the control module is used for outputting a control signal to the driving circuit to enable the input current or the input voltage of the first motor to change along with the position change of the rotor of the first motor, so that the actual torque of the first motor reaches or basically reaches the target torque within a first preset time, and the first preset time is less than 100 ms.
Optionally, the operating device is further configured to set a target rotational speed of the first motor; the actual rotating speed of the first motor reaches or basically reaches the target rotating speed within a second preset time, and the second preset time is less than 800 ms.
Optionally, the method further comprises: and the target rotating speed detection module is connected with the operating device in an associated manner and is used for detecting the target rotating speed of the first motor set by the operating device.
Optionally, the riding lawn mower further comprises: a current detection module for detecting a current of the first motor; the current detection module is connected with the first motor and the control module; a target rotation speed detection module for detecting a target rotation speed of the first motor set by the operation device; the target rotating speed detection module is connected with the operating device in a correlation manner and is connected with the control module; an actual rotation speed detection module for detecting an actual rotation speed of the first motor; the actual rotating speed detection module is connected with the first motor in a correlation mode and connected with the control module.
Optionally, the riding lawn mower further comprises: a current detection module for detecting a current of the first motor; the current detection module is connected with the first motor and the control module; a target rotation speed detection module for detecting a target rotation speed of the first motor set by the operation device; the target rotating speed detection module is connected with the operating device in a correlation manner and is connected with the control module; an actual rotation speed estimation module for detecting that the actual rotation speed of the first motor is estimated based on the detected current of the first motor by the current detection module; the actual rotating speed estimation module is connected with the current detection module and the control module.
Optionally, the riding lawn mower further comprises: the rotor position detection module or the rotor position estimation module is used for acquiring the rotor position of the first motor, and the rotor position detection module or the rotor position estimation module is connected with the control module; the control module outputs a control signal that varies with the change in the rotor position based on the rotor position.
Optionally, the target rotation speed detection module is connected to the control module through a bus.
Optionally, the communication frame rate of the bus is in a range of 100Hz to 3000 Hz.
Optionally, the first preset time is less than 60 ms.
Optionally, the target rotation speed detection module includes a sensor, and a data refresh rate of the sensor ranges from 50 microseconds/time to 10 milliseconds/time.
Optionally, the first preset time is less than 10 ms.
Optionally, the target rotation speed detection module includes a sensor, and a data refresh rate of the sensor ranges from 50 microseconds/time to 10 milliseconds/time.
Optionally, the first preset time is less than 60 ms.
Optionally, the stator flux linkage of the first motor and the rotor flux linkage have an angle of 90 °.
Optionally, the included angle between the stator flux linkage and the rotor flux linkage is in the range of 90 ° to 135 °.
Optionally, the input voltage of the first motor varies in a sine wave or saddle wave manner, and the input current of the first motor varies in a sine wave manner.
Optionally, the operation device comprises:
at least one bracket mountable on the riding lawn mower;
an operating lever arranged to rotate about a first pivot axis at least in a first direction;
a pivot assembly including a first pivot assembly having a first pivot axis, the first pivot assembly configured to pivotally mount the lever on the bracket such that the lever pivots about the first pivot axis in a first direction;
the target rotating speed detection module comprises a position detection module, the position detection module is connected with the operating rod in a correlation mode and is used for detecting the position of the operating rod in the first direction, and the position of the operating rod in the first direction corresponds to the target rotating speed of the first motor.
Optionally, the operating device comprises a steering wheel and a speed lever, and the target rotation speed detection module is connected with the steering wheel and/or the speed lever in an associated manner and is used for detecting a target rotation speed and a target torque of the first motor set by the steering wheel and/or the speed lever.
Optionally, the control module comprises: a first rotating speed ring for generating a target current of the first motor according to a target rotating speed and an actual rotating speed of the first motor.
Optionally, the control module further comprises: a current distribution unit for distributing a direct axis target current and a quadrature axis target current according to the target current of the first motor generated by the first rotation ring; the current conversion unit is used for generating a direct-axis actual current and a quadrature-axis actual current according to the actual current of the first motor and the rotor position of the first motor; the first current loop is used for generating a first voltage regulating quantity according to the direct-axis target current and the direct-axis actual current; the second current loop is used for generating a second voltage regulating quantity according to the quadrature axis target current and the quadrature axis actual current; and the control signal generating unit is used for generating a control signal according to the first voltage regulating quantity and the second voltage regulating quantity, and the control signal is used for controlling the driving circuit.
Optionally, the control module comprises: and the second rotating speed ring is used for generating the target torque of the first motor according to the target rotating speed and the actual rotating speed of the first motor.
Optionally, the control module further comprises: a torque loop for generating a first adjustment amount according to a target torque and an actual torque of the first motor; a magnetic chain loop for generating a second adjustment amount according to a target stator flux linkage and an actual stator flux linkage of the first motor; and the control signal generating unit is used for generating a control signal according to the first regulating quantity and the second regulating quantity, and the control signal is used for controlling the driving circuit.
Alternatively, there is a dead zone section in which the target rotation speed of the first motor is constant between the operation position of the operation device and the target rotation speed of the first motor.
Alternatively, there is a dead zone section between the operating position of the operating device and the target torque of the first motor in which the target torque of the first motor is constant.
The riding type mower can improve the response speed of the motor driving the travelling wheels to travel, and is good in user operation experience and safety.
Drawings
Fig. 1 is an external view of a riding lawn mower as an embodiment;
fig. 2 is an operating device of the riding mower as an embodiment;
FIG. 3 is the operating device of FIG. 2 from another perspective;
FIG. 4 is a partial block diagram of the operating device shown in FIG. 2;
FIG. 5 is a control system block diagram of a first motor of the riding lawn mower including a left motor and a right motor;
FIG. 6 is a block diagram of a control system for a first motor of one of the left and right motors of an embodiment;
FIG. 7 is a block diagram of a control system for a first motor of one of the left and right motors of another embodiment;
FIG. 8 is a block diagram of a control system of a more specific first motor as an embodiment;
FIG. 9 is a space vector diagram of a motor in one embodiment;
FIG. 10 is a space vector diagram of a motor in another embodiment;
FIG. 11 is a graph of permanent magnet torque T1, reluctance torque T2, and electromagnetic torque Te versus electrical angle for the motor of FIG. 10 at the same current;
fig. 12 is a block diagram of a control system of a more specific first motor as another embodiment;
FIG. 13 is a space vector diagram of the electric machine under the control system of the first motor shown in FIG. 12;
fig. 14 is a corresponding relationship between the target rotational speed of the operation lever and the first motor, the actual rotational speed of the first motor, and the output torque, the maximum output torque;
FIG. 15 is a sine wave variation of the three phase voltage of the motor with rotor position;
FIG. 16 is a saddle wave variation of the three phase voltage of the motor with rotor position;
fig. 17 is an external view of a riding mower according to another embodiment.
Detailed Description
The invention is described in detail below with reference to the figures and the embodiments.
Referring to fig. 1, a riding lawn mower 10 as an embodiment includes: frame 11, seat 12, power take-off assembly 13, walking assembly 14, operating device 15, power supply unit 16.
A frame 11 for carrying a seat 12, the frame 11 extending at least partially in a direction parallel to the front-rear direction; a seat 12 is provided for seating an operator, and the seat 12 is mounted to the frame 11. The power output assembly 13 is connected to the frame 11, the power output assembly 13 includes an output member for outputting power to realize a mechanical function, for example, in the present embodiment, the output member may be a blade 131 for realizing a grass cutting function, and the power output assembly 13 further includes a second motor 144 for driving the blade 131 to rotate at a high speed. The power take-off assembly 13 may include more than one blade 131 and, correspondingly, the number of second motors 144 may correspond to the number of blades 131.
The walking assembly 14 is used to enable the riding mower 10 to walk on the lawn. The walking assembly 14 may specifically include: the first and second road wheels 141 and 142 have the number of first road wheels 141 of 2 and the number of second road wheels 142 of 2, and in the present embodiment, the first road wheels 141 are driving wheels including left and right driving wheels 141L and 141R. The running assembly 14 further includes a first motor 143 for driving the first running wheel 141, the number of the first motors 143 also being 2, a left motor 143L and a right motor 143R (fig. 5), respectively.
Thus, when the two first motors 143 drive the corresponding two first traveling wheels 141 to rotate at different rotational speeds, a speed difference is generated between the two first traveling wheels 141, so that the riding mower 10 is steered.
The power supply device 16 is used to supply electric power to the riding mower 10. Specifically, the power supply device 16 is used to power the first motor 143, the second motor 144, and other electronic components or electronic assemblies on the riding mower 10. In some embodiments, power supply device 16 is disposed on a rear side of seat 12 on frame 11. The power supply device 16 includes at least one battery pack 161 for providing a source of energy to the riding mower 10, the at least one battery pack 161 being further configured to provide a source of energy to another power tool 20.
The operating device 15 is used to set at least a target rotation speed of the first motor 143, and further, a target state of the riding mower 10 can be set by the operating device 15, and the target state of the riding mower 10 includes a forward state, a backward state, a forward speed, a backward speed, a zero speed, a ready-to-operate state (including power-on of the electronic module, etc.) or a standby-to-operate state (i.e., a parking state) of the riding mower 10. The operator can use the operating device 15 to control the walking of the riding mower 10 or to determine the operating state of the riding mower 10.
In the present embodiment, the operating device 15 is at least used for the operator to control the first motor 143 in the walking assembly 14, and thus the riding lawn mower 10 to walk on the lawn, and specifically, the operating device 15 is at least used for setting the target rotation speed of the first motor 143. Optionally, the operating device 15 is also for use by an operator to bring the riding lawn mower 10 into or out of an operating state. In the present embodiment, the number of the operating devices 15 is 2, and the right and left operating devices 15R and 15L are respectively used for correspondingly controlling the right and left motors 143R and 143L to drive the left second road wheel right driving wheel 141R and the left driving wheel 141L, respectively. The two operating devices 15 are identical in component parts and are located on the right and left hand sides, respectively, of an operator sitting on the seat 12 for ease of operation.
The left operating device 15L and the right operating device 15R have the same structural composition, and the structural composition of the operating devices will be described below, and for convenience of description, the same description will be given with respect to the operating devices 15. With reference to fig. 2 to 4, as a possible embodiment, the operating device 15 comprises: at least one bracket 152 mountable on the riding mower 10, specifically, the bracket 152 is fixedly mounted on the frame 11; a lever assembly including a lever 151, the lever 151 being arranged to rotate about a first axis a in a first direction F1 between a forward position, a middle position, and a rearward position, and about a second axis B in a second direction F2 between an inboard position and an outboard position; and a pivoting combination for pivotably mounting the operating lever 151 on the bracket 152 such that the operating lever 151 rotates about the first axis a in the first direction F1 and about the second axis B in the second direction F2. In the present embodiment, the second axis B and the first direction F1 extend in the front-rear direction thereof, and the first axis a and the second direction F2 extend in the left-right direction thereof, for an operator sitting on the seat 12.
The pivot assembly includes a first pivot assembly 153, the first pivot assembly 153 being mounted on the bracket 152. The first pivot assembly 153 includes a first pivot 1531 fixedly mounted to the first bracket 152, the first pivot 1531 defining a first axis a. In some embodiments, first pivot assembly 153 further includes a bushing (not shown). The sleeve partially surrounds the first pivot 1531 and is rotatable about the first pivot 1531. The first pivot assembly 153 allows the operating rod 151 to rotate around a first axis a in the first direction F1, where the first axis a is an axis of the first pivot 1531. When the operating lever 251 rotates in the first direction F1 about the first axis a between the forward position, the middle position, and the backward position, the first pivoting assembly 253 is rotated about the first axis a in the first direction F1.
The position of the operating lever 151 in the first direction F1 corresponds to the target rotational speed and the target state of the first motor 143, which are set by the operator and include forward, reverse, and stall states. In the present embodiment, the positions in the first direction F1 include the forward position, the middle position, and the reverse position, which correspond to the forward, zero speed, and reverse states of the riding mower 10, respectively. The operating lever 151 provides a plurality of target traveling speeds in the forward direction between the forward position and the middle position, and the operating lever 151 provides a plurality of target traveling speeds in the reverse direction between the middle position and the reverse position. The operator sets the target rotation speed and the target state of the first motor 143 by pushing the operation lever 151 to rotate to different positions in the first direction F1.
Optionally, the pivot assembly further comprises a second pivot assembly 154, the second pivot assembly 154 being mounted on the first pivot assembly 153. 154 includes a second pivot 1541 fixedly mounted on first pivot assembly 153, second pivot 1541 defining a second axis B. Specifically, second pivot 1541 of second pivot assembly 154 is fixedly mounted in a mounting hole provided in a bushing (not shown) of first pivot assembly 153. The operating lever 151 is pivotably mounted on the second pivot 1541 and is rotatable about the second pivot 1541. The operating lever 151 is provided with a through hole through which the second pivot 1541 passes, and the operating lever 151 is rotatable about the second pivot 1541. The second pivot assembly 154 allows the operating rod 151 to rotate around a second axis B in the second direction F2, where the second axis B is the axis of the second pivot 1541. When the operating lever 151 rotates in the second direction F2 between the inner position and the outer position about the second pivot 1551, the second pivot assembly 155 is rotated about the second pivot 1551 in the second direction F2.
The operator sets target states of the riding lawn mower, including an operating state (i.e., a ready state or a stall state) and a non-operating state (i.e., a parking state), by pushing the operating lever 151 to rotate to different positions (inner position or outer position) in the second direction F2. The inside position of the operating lever 151 in the second direction F2 coincides with the middle position of the operating lever 151 in the first direction F1, and the user can turn on the riding mower 10 at the outside position.
The target traveling direction of the riding mower 10 is determined by a target traveling speed difference indicated by the user operating the left operation lever 151R and the right operation lever 151L. That is, if both the left and right levers 151L and 151R are pushed in the forward direction and the target travel speed given by the left lever 151L is greater than the target travel speed given by the right lever 151R, the riding mower turns forward and to the right; if both the left and right levers 151L and 151R are pushed in the forward direction and the target travel speed given by the left lever 151L is less than the target travel speed given by the right lever 151R, the riding mower 10 turns forward and left; if both the left and right levers 151L and 151R are pushed in the forward direction and the target travel speed given by the left lever 151L is equal to or substantially equal to the target travel speed given by the right lever 151R, the riding mower 10 travels at a substantially constant speed at the target travel speed given by the left and right levers. Similarly, if both the left and right levers 151L and 151R are pushed in the backward direction, the riding lawn mower 10 walks and turns in accordance with the target traveling speed difference given by the left and right levers 151L and 151R by the target traveling speed difference given by the left and right levers 151L and 151R. Since the rotation speed of the motor is related to the torque, the operation device 15 sets the target rotation speed of the first motor 143 and also sets the target torque of the first motor accordingly.
Referring to fig. 5, a motor control system block diagram of the riding mower 10 includes a left motor control system and a right motor control system, where the left motor control system and the right motor control system have the same or similar functions and compositions, and taking the left motor control system as an example, the motor control system block diagram mainly includes: a left motor control module 50L, a left motor target rotational speed detection module 51L, a left motor actual rotational speed detection module 52L, a left motor drive circuit 53L, a left motor current detection module 54L, and a left motor 143L.
The left motor control module 50L is used for controlling the operation of the left motor 143L, and is connected to the left motor target rotational speed detection module 51L, the left motor actual rotational speed detection module 52L, the left motor driving circuit 53L, and the left motor current detection module 54L, and is used for adjusting the control amount of the left motor 143L according to the detection signals of the left motor target rotational speed detection module 51L, the left motor actual rotational speed detection module 52L, and the left motor current detection module 54L, and outputting a control signal to the left motor driving circuit 53L, so as to control the left motor driving circuit 53L to make the left motor driving circuit 53L drive the left motor 143L to reach or substantially equal to the target rotational speed set by the left operation device 15L as soon as possible. The control amount of the left motor 143L includes an input voltage and/or an input current of the left motor 143L.
The left motor target rotation speed detection module 51L is connected to the left operating device 15L in an associated manner, and is configured to detect a state of the left operating device 15L and output the state to the left motor control module 50L, so that the left motor control module 50L can obtain the target rotation speed of the left motor 143L according to a detection result of the left motor target rotation speed detection module 51L. In the present embodiment, a left motor target rotation speed detection module 51L is provided in association with the left operation lever 151L for detecting the position of the left operation lever 151L. The left motor target rotational speed detection module 51L includes an angle sensor or a position sensor for detecting a rotated angle or a rotated position of the operation lever 151 of the operation device 15.
The left motor actual rotation speed detection module 52L is connected to the left motor 143L in an associated manner, and is configured to detect an actual rotation speed of the left motor 143L. Alternatively, the left motor actual rotation speed detection module 52L includes a speed detection sensor disposed near or inside the left motor 143L to acquire the actual rotation speed of the left motor 143L, for example, a photosensor disposed near the left motor 143L to acquire the actual rotation speed of the left motor 143L, or, for example, a hall sensor disposed near a rotor inside the left motor 143L to acquire the actual rotation speed of the left motor 143L according to the speed at which the rotor rotates.
However, in some cases, especially when the first motor 143 is operated at high speed and/or high temperature, or the first traveling wheel 141 is operated at high speed and/or high temperature, or the riding mower is operated at high temperature, the sensor detection accuracy may be affected, and even the speed detection sensor detection may be disabled. Therefore, in order to solve this problem, as another embodiment, the left motor actual rotation speed detection module 52L does not include a sensor, the left motor actual rotation speed detection module 52L is a brushless motor, and the periodic variation of the left motor actual rotation speed detection module 52L is obtained by detecting the current and/or voltage of the left motor 143L, for example, by periodically varying the counter electromotive force output by the left motor actual rotation speed detection module 52L, so as to determine the zero-crossing point of the counter electromotive force, thereby obtaining the actual rotation speed of the left motor 143L actual rotation speed detection module 52L. Through the mode, the actual rotating speed of the left motor actual rotating speed detection module 52L does not need to be detected by a sensor, the cost is reduced, and meanwhile, the whole structure is more simplified besides the detection precision is not influenced by high rotating speed and temperature.
A left motor current detection module 54L connected in association with the left motor 143L for obtaining a current of the left motor 143L, wherein the current may be a bus current of the motor or a phase current of the left motor 143L. The left motor current detection module 54L transmits the current obtained from the left motor 143L to the left motor control module 50L.
The left motor driving circuit 53L is connected to the left motor control module 50L and the left motor 143L, and is configured to control the operation of the left motor 143L according to a signal output by the left motor control module 50L.
Alternatively, the left motor 143L may be connected to the left driving wheel 141L through the reduction gear 55L, and the output rotation speed of the left motor 143L is reduced by the reduction gear 55L and then output to the left driving wheel 141L to drive the left driving wheel 141L to rotate, so that the torque of the left motor 143L is transmitted to the left driving wheel 141L through the reduction gear to drive the left driving wheel 141L. In other embodiments, the left motor 143L and the left drive wheel 141L are directly coupled.
The right and left motor control system mainly comprises: a left motor control module 50R, a left motor target rotational speed detection module 51R, a left motor actual rotational speed detection module 52R, a left motor drive circuit 53R, a left motor current detection module 54R, and a left motor 143R. The functions and the components of the right and left motor control systems are the same or similar, and are not described in detail herein.
In the above embodiment, the left and right motor actual rotation speed detection modules 52L and 52R may be two separately disposed modules, which are respectively connected to the left and right motors 143L and 143R for generating the actual rotation speeds of the left and right motors 143L and 143R. Of course, the left motor actual rotational speed detection module 52L and the right motor actual rotational speed detection module 52R may also be an integration of the two modules.
In the above embodiment, the left and right motor target rotation speed detection modules 51L and 51R respectively associated with the right and left operation levers 151R and 151L may be separate modules or may be an integrated module.
In the above embodiment, the left motor control module 50L and the left motor target rotational speed detection module 51L are connected by the bus 56, the target rotational speed of the left motor 143L detected by the left motor target rotational speed detection module 51L through the setting of the left operation device 15L can be transmitted to the left motor control module 50L through the bus 56, and the left motor control module 50L receives the detection result from the left motor target rotational speed detection module 51L through the bus 56. Optionally, the communication frame rate of the bus is in a range of 100Hz to 2000 Hz. Optionally, the communication frame rate of the bus is in a range of 200Hz to 2000 Hz. Optionally, the communication frame rate of the bus is in a range of 300Hz to 3000 Hz.
In some embodiments, the communication frame rate of the bus is in a range of 100Hz to 1000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 200Hz to 800 Hz. In some embodiments, the communication frame rate of the bus is in a range of 100Hz to 500 Hz. In some embodiments, the bus has a communication frame rate in a range of 500Hz to 1000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 500Hz to 1500 Hz. In some embodiments, the communication frame rate of the bus is in a range of 1000Hz to 2000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 1000Hz to 1500 Hz. The communication frame rate of the bus refers to the number of times the bus receives and/or transmits data packets in one second.
In this way, the data transmission rate between the left motor control module 50L and the left motor target rotational speed detection module 51L is increased, so that the response speed of the first motor 143 can be increased to some extent.
Similarly, the right motor control module 50R and the right motor target rotational speed detection module 51R are also connected via the bus 56, and will not be described herein. Of course, the right motor control module 50R and the right motor target rotational speed detection module 51R may be connected by another bus.
Alternatively, the left and right motor target rotation speed detection modules 51L and 51R include angle sensors, position sensors, and the like for detecting the angle of rotation or the rotational position of the operation lever 151 of the operation device 15. In other embodiments, the operating device 15 of the riding mower 10 includes a steering wheel 751 and a speed lever 752 (throttle) (fig. 17) for setting at least a target speed of the first motor 141. The target speed of the first motor 141 is determined by a combination of the steering wheel 751 and the speed lever 752, which gives the target speed, and the angle of rotation of the steering wheel 751 is used to distribute the distribution speeds of the left and right motors. The operator can control the target rotation speed of the riding mower 10 at which the first motor 141 is provided by rotating the steering wheel 751 and the foot lever 752, and by the rotation angle of the steering wheel 751 and the position of the lever 752. The operator may control steering, such as steering, or straight-going, of the riding mower 10 by operating the steering wheel, and the speed lever 752 is used to determine a target speed of the motor. Optionally, the steering wheel 751 is an electronic steering wheel.
Alternatively, the left and right motor target rotation speed detection modules 51L and 51R include sensors. Optionally, the data refresh rate of the sensor ranges from 50 microseconds/time to 10 milliseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 50 microseconds/time to 200 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 300 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 200 microseconds/time to 500 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 500 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 1 ms/time to 10 ms/time.
Referring to fig. 2 to 4, as one possible embodiment, the left and right motor target rotation speed detection modules 51L and 51R include a position detection module 17, and the position detection module 17 includes a magnetic element 171 and a magnetic sensor 172. In the present embodiment, the magnetic sensor is a hall sensor. In other embodiments, the magnetic sensor is a magnetoresistive sensor.
The magnetic element 171 or the magnetic sensor 172 is disposed in association with the operating lever 151 or the pivot combination, and the magnetic sensor 172 is disposed at an interval from the magnetic element 171 such that when the operating lever 151 is rotated in the first direction F1 about the first axis a, the magnetic element 171 and the magnetic sensor 172 can be driven to rotate relatively to detect the forward position, the middle position, and the reverse position of the operating lever 151 in the first direction F1.
Alternatively, when the operating lever 151 rotates about the second axis B in the second direction F2, the magnetic element 171 and the magnetic resistance sensor 172 can be driven to generate relative displacement to detect the inner position and the outer position of the operating lever 151 in the second direction F2.
The magnetic element 171 is disposed in association with the operating rod 151 and is capable of following the movement of the operating rod 151, and the magnetic sensor 172 is fixedly mounted on the bracket 152, and the magnetic element 171 and the magnetic sensor 172 are disposed in correspondence such that, when the operating rod 151 rotates in the first direction F1 about the first axis a, a relative movement is generated between the magnetic element 171 and the magnetic sensor 172, and the magnetic sensor 172 outputs a first detection signal related to the position of the operating rod 151 in the first direction.
Alternatively, when the operating lever 151 rotates about the second axis B in the second direction F2, the magnetic element 171 and the magnetic sensor 172 can generate relative motion, and the magnetic sensor 172 can output a second detection signal related to the position of the operating lever 151 in the second direction F2.
The magnetic element 171 is mounted on the operation rod 151, and specifically, the operation rod 151 is provided with a first mounting portion 1511, the first mounting portion 1511 is integrally formed with or fixedly mounted on the operation rod 151, and the mounting portion 1511 is used for mounting the magnetic element 171 so as to fix the magnetic element 171 and the operation rod 151 together, so that the magnetic element 171 and the operation rod 151 can move synchronously.
The magnetic sensor 172 is fixedly mounted on the bracket 152, specifically, a second mounting portion 1521 is disposed on the bracket 1521, the second mounting portion 1521 is integrally formed with or fixedly mounted on the operating rod 151, and the second mounting portion 1521 is used for mounting the magnetic sensor 172. The second mounting portion is also used for mounting the PCB 18, the magnetic sensor 172 is disposed on the PCB 18, and the magnetic sensor 172 is sealed on the PCB by potting in order to firmly fix the magnetic sensor 172 on the PCB 18.
The first mounting portion 1511 and the second mounting portion 1521 are provided at positions corresponding to each other so that the magnetic sensor 172 can output detection signals that satisfy the requirements with respect to the position of the operation lever 151 in the first direction and the position in the second direction F2.
The position detection module 17 is at least partially associated with the bracket 152 and/or the pivot assembly or the operating lever 151 for detecting the position of the operating lever 151 in the first direction F1, including a forward position, a middle position, and a reverse position, for example, when the operating lever 151 is in the forward position, the target state of the corresponding first motor 143 is the maximum forward speed; when the operation lever 151 is at the reverse position, the target state of the corresponding first motor 143 is the maximum reverse speed; when the operation lever 151 is in the middle position, the target state of the corresponding first motor 143 is zero speed. The operator sets the target rotation speed of the corresponding first motor 141 by moving the operation lever 151, and controls the operation of the corresponding first motor 141, so that the target rotation speed of the corresponding first motor 141 is also the target rotation speed or the target state set by the operator obtained from the position of the operation lever 151.
Alternatively, the position detection module 17 can also detect the position of the operating rod 151 in the second direction F2, including an inner position and an outer position. When the operating lever 151 is in the inboard position, the corresponding state of the riding mower 10 is the working state (i.e., the ready state), in some embodiments, the inboard position coincides with or is close to the mid-range position, and the target state of the corresponding first motor 143 is the zero speed state; when the operation lever 151 is in the outside position, the corresponding state of the riding mower 10 is the non-operating state.
In the present embodiment, the magnetic element 171 and the magnetic sensor 172 are disposed in association with each other such that when the operating lever 151 is rotated about the first axis a in the first direction F1 to bring the magnetic element 171 and the magnetic sensor 172 into relative rotation, the magnetic sensor 172 outputs detection signals relating to the forward position, the middle position, and the reverse position of the operating lever 152 in the first direction F1. The detection signal includes position information of the operation lever 151, and the position of the operation lever 152 in the first direction F1 including the forward position, the middle position, and the reverse position is detected in such a manner that different positions of the operation lever 152 in the first direction F1 correspond to different target speeds and rotational directions of the first motor 143, and the target rotational speed of the first motor 143 can be obtained by detecting the position of the operation lever 152.
Of course, it is understood by those skilled in the art that the installation positions of the magnetic element 171 and the magnetic sensor 172 of the position detection module 17 are not limited to the above-mentioned manner, and it is within the scope of the present invention to arrange the magnetic element 171 and the magnetic sensor 172 of the position detection module 17 in a spaced and associated manner, and to associate the magnetic element 171 and the magnetic sensor 172 with the position of the operation rod 151 in the first direction and the position of the operation rod 151 in the second direction so that the magnetic element 171 and the magnetic sensor 172 can generate relative movement when the operation rod 151 rotates.
In the present embodiment, two magnetic sensors 172, a first magnetic sensor 172a and a second magnetic sensor 172b, are employed, which are disposed at different positions on the substrate or PCB. As a specific embodiment, the first and second magnetic sensors 172a and 172b may be symmetrically disposed about a center line of the magnetic element. In other embodiments of the present invention, a plurality of hall sensors may be used, which are located at different positions on a substrate or a PCB, to detect the position of the operation rod 151 in the first direction F1.
Specifically, the principle that the magnetic sensor 172 and the magnetic element 171 detect the position of the operation lever 151 in the first direction F is as follows:
referring to fig. 3 and 4, when the operating rod 251 rotates in the first direction F1 to rotate the magnetic element 171, the magnetic sensor 172 and the magnetic element 171 rotate relatively by a relative rotation angle, and since the voltage of the magnetic sensor 172 and the magnetic field strength are in a linear relationship, the relative position relationship between the magnetic sensor 172 and the magnetic element 171 can be determined according to the output voltages of the two magnetic sensors 172, so that the relationship between the output voltage of the magnetic sensor 172 and the position of the operating rod 151 can be calibrated, and the calibration result is stored in the control module (30, 50, 60), so that the control module (30, 50, 60) can determine the position of the corresponding operating rod 151 according to the output voltage of the magnetic sensor 172.
Referring to fig. 3, assuming that fig. 3 shows that the backward position of the operation lever 151 in the first direction F1 is the maximum backward position, and the forward position of the operation lever 151 in the first direction F1 is the maximum forward position, when the operation lever 151 is rotated from the backward position to the forward position, the output voltages of the two magnetic sensors 172 change with the position of the movement of the operation lever 151. By calibrating the positional relationship between the output voltages of the two magnetic sensors 172 and the operation lever 151, the current position of the operation lever 151 can be determined from the output voltages of the two magnetic sensors 172.
In this embodiment, because of adopting above-mentioned structure, make the sensor fixed setting, and magnetic element and action bars associative connection, the relative position relation between magnetic element and the sensor is utilized to carry out the mode that the position detection of action bars in two directions, can reduce the sensor because of the detection result that the motion caused is inaccurate and the connecting wire of sensor because of frequently removing and dragging the problem that damages sensor, connecting wire and circuit for the detection result is more reliable, and the reliability of system is higher and the structure is simpler.
Referring to fig. 6, as a control system of the first motor 143 according to an embodiment, it may be applied to any one of the left and right motor control systems described above. In the present embodiment, the first motor 143 is a motor 38, and the motor 38 may be a brushless motor. The motor 38 has a stator, a rotor, and stator windings.
The control system of the first motor 143 of the present embodiment includes: a control module 30, a power supply 31, a power circuit 32, a drive circuit 33, a target rotational speed detection module 34, an actual rotational speed detection module 35, a rotor position detection module 36, a current detection module 37, a motor 38, a bus 39, and an operating device 15 as previously described.
The control module 30 is used to control the operation of the motor 38. In some embodiments, the control module 30 employs a dedicated controller, such as a dedicated control chip (e.g., MCU). The control module 30 is integrated with a signal processing unit, wherein the signal processing unit is used for processing the acquired related parameter signal, and has functions of calculation, comparison, judgment and the like, and after the signal processing unit processes the signal, the signal processing unit can generate a control signal and output the control signal to the driving circuit 33 to drive the motor 38 to operate.
The power supply 31 is used for supplying power to the control system of the motor 38, and in the present embodiment, the power of the power supply 31 is supplied from the power supply device 16. The power circuit 32 is connected to the power source 31, and the power source 31 is configured to receive power from the power source 31 and convert the power of the power source 31 into power for at least the control module 30.
The drive circuit 33 is electrically connected to the control module 30 and the motor 38, and is capable of operating the motor 38 in accordance with control signals output by the control module 30. In one embodiment, the motor 38 is a three-phase motor having three-phase windings, and the driving circuit 33 is electrically connected to the three-phase windings of the motor 38. The driving circuit 33 specifically includes a switching circuit, and the switching circuit is configured to drive the rotor of the motor 38 to operate according to the control signal of the control module 30.
In order to rotate the motor 38, the driving circuit 33 has a plurality of driving states, in which a magnetic field is generated by the stator winding of the motor, and the control module 30 is configured to output a corresponding driving signal to the driving circuit 33 according to the rotor rotation position of the motor 38 to enable the driving circuit 33 to switch the driving states, so as to change the state of the voltage and/or current applied to the winding of the motor 38, generate an alternating magnetic field to drive the rotor to rotate, and thus drive the motor.
The rotor position of the motor 38 can be obtained by the rotor position detection module 36, and the rotor position detection module 36 includes, for example, 3 hall sensors, which are arranged along the circumferential direction of the rotor of the motor 38, and when the rotor rotates into and out of a preset range, the signals of the hall sensors change, and the output signal of the rotor position detection module 36 also changes, so that the position of the rotor of the motor can be known according to the detection signal output by the rotor position detection module 36.
Of course, the rotor position can also be estimated from the motor current. Referring to fig. 7, the rotor position estimation module 46 is derived from an estimation of the current of the motor obtained by the current detection module 47. The rotor position estimation module 46 may be internal to the control module 40 or external to the control module 40.
The driving circuit 33 shown in fig. 6 includes switching elements VT1, VT2, VT3, VT4, VT5 and VT6, and switching elements VT1, VT2, VT3, VT4, VT5 and VT6 form a three-phase bridge, where VT1, VT3 and VT5 are upper bridge switches, and VT2, VT4 and VT6 are lower bridge switches. The switching elements VT1 to VT6 may be field effect transistors, IGBT transistors, or the like. The control terminals of the switch elements are electrically connected to the control module 30. The switching elements VT1 VT6 change the on state according to the driving signal outputted from the control module 30, so as to change the voltage and/or current state of the power supply 31 applied to the winding of the motor 38, thereby driving the motor 38 to operate.
The target rotation speed detection module 34 is connected to the operation device 15, and in the present embodiment, the target rotation speed detection module 34 is connected to the operation lever 151 of the operation device 15, and the target rotation speed detection module 34 can acquire the target rotation speed corresponding to the first motor 143 set by the user through the operation lever 151. In the present embodiment, the target rotation speed detection module 34 may employ the position detection module 17 shown in fig. 2 and 4.
The actual rotation speed detection module 35 is connected to the motor 38 for detecting an actual rotation speed of the motor 38. Alternatively, the actual rotation speed generation module 35 includes a speed detection sensor disposed near or inside the motor 38 to obtain the actual rotation speed of the motor 38, for example, a photoelectric sensor disposed near the motor 38 and capable of obtaining the rotation speed of the motor 38, and as another example, a hall sensor disposed near a rotor inside the motor 38 and capable of obtaining the actual rotation speed of the motor 38 according to the rotation speed of the rotor.
However, in some cases, especially when the first motor 143 is operated at high speed and/or high temperature, or the first traveling wheel 141 is operated at high speed and/or high temperature, or the riding mower is operated at high temperature, the sensor detection accuracy may be affected, and even the speed detection sensor detection may be disabled. To solve this problem, as another embodiment, the actual rotation speed detection module 35 does not include a sensor, but is obtained by estimating an electric signal output by the motor 38, for example, by detecting a current of the motor 38, and obtaining a zero-crossing point of a back electromotive force of the motor 38, so that a periodic variation law of the operation of the motor 38 is obtained, and the actual rotation speed of the motor 38 is obtained according to the periodic variation law. Referring to fig. 7, the actual rotation speed estimation module 45 is connected to the current detection module 47, and obtains the actual rotation speed of the motor 38 according to the current of the motor output by the current detection module 47. Through the mode, the actual rotating speed of the motor 38 is detected without a sensor, the cost is reduced, and meanwhile, the detection precision is not influenced by high rotating speed and temperature, and the whole structure is more simplified. The motor 38 may be an inner rotor motor or an outer rotor motor. In some embodiments, motor 38 is an inner rotor brushless motor, and optionally, motor 38 is an inner rotor permanent magnet synchronous brushless motor. In some embodiments, motor 38 is an outer rotor brushless motor, and optionally, motor 38 is an outer rotor permanent magnet synchronous brushless motor.
The actual rotation speed detection module 35 and the rotor position detection module 36 shown in fig. 6 may be integrated together and may be separately provided. The actual rotational speed estimation module 45 and the rotor position estimation module 46 shown in fig. 7 may be integrated together and may be separately provided.
The current detection module 37 is connected to the motor 38 for obtaining an operating current of the motor 38, where the current may be a bus current of the motor 38 or a phase current of the motor 38. The current detection module 37 transmits the acquired current of the motor 38 to the control module 30.
The control module 30 is connected to the target rotation speed detection module 34, the actual rotation speed detection module 35, the current detection module 37, and the motor rotor position detection module 36, and is configured to adjust a control amount of the motor 38 according to a target rotation speed of the motor 38 and an actual rotation speed of the motor 38, which are set by a user through the operation device 15 and detected by the target rotation speed detection module 34, and output a control signal to control the motor 38 so that the actual rotation speed of the motor 38 reaches or substantially reaches the target rotation speed within a preset time, so as to increase a user experience feeling, and prevent a danger from occurring due to backward slip of the riding mower caused by a response hysteresis of the motor 38 during climbing of the lawn mower.
In this embodiment, the control module 30 outputs a control signal to the driving circuit 33 to make the input current or the input voltage of the first motor 143 change along with the position change of the rotor of the first motor 143, so that the actual torque of the first motor 143 reaches or substantially reaches the target torque within a first preset time, where the first preset time is less than 100 ms. In some embodiments, the first preset time is less than 80 ms. In some embodiments, the first preset time is less than 50 ms. In some embodiments, the first preset time is less than 20 ms. When the difference between the actual torque of the first motor 143 and the target torque is less than 10% of the target torque, it is considered that the target torque is substantially reached.
Accordingly, the actual rotational speed of the first motor 143 can reach or substantially reach the target rotational speed in a relatively short time. Optionally, the actual rotation speed of the first motor 143 reaches or substantially reaches the target rotation speed within a second preset time, and the second preset time is less than 800 ms. In some embodiments, the second preset time is less than 600 ms. In some embodiments, the second preset time is less than 300 ms. When the difference between the actual rotation speed of the first motor 143 and the target rotation speed is less than 10% of the target torque, it is considered that the target rotation speed is substantially reached.
In the present embodiment, the input voltage of the first motor 143 varies in a sine wave or saddle wave manner, and the input current of the first motor varies in a sine wave manner. Alternatively, the motor 38 is a three-phase motor, and the input current or the input voltage of the motor 38 is changed in a three-phase symmetrical sine wave manner, such as the three-phase voltages Uu, Uv, and Uw applied to the motor 38 in fig. 15, or the input voltage of the motor 38 is changed in a three-phase symmetrical saddle wave manner, such as the three-phase voltages Uu, Uv, and Uw applied to the motor 38 in fig. 16. In the present embodiment, the three-phase voltages Uu, Uv, and Uw mutually form a phase angle of 120 °. The input current of the motor 38 varies in a sine wave manner in accordance with the input voltage.
The control module 30 is connected to the target speed detection module 34 via a bus 39. The target speed detection module 34 sends data to the target speed detection module 34 via the bus 39, and the control module 30 receives data via the bus 39. The communication frame rate of the bus is in the range of 10Hz to 600 Hz. In this way, the data transmission rate between the left motor control module 50L and the left motor target rotation speed detection module 51L can be increased to some extent, thereby further increasing the response speed of the electric machine 58. The target speed detection module 34 includes a sensor having a data refresh rate in a range of 50 microseconds/time to 10 milliseconds/time to further increase the response speed of the motor 58.
In some embodiments, the data refresh rate of the sensor ranges from 50 microseconds/time to 200 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 300 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 200 microseconds/time to 500 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 500 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 1 ms/time to 10 ms/time.
Referring to fig. 8, as a more specific embodiment of a control system of the first motor 143, the control system includes: the device comprises a control module 50, a power supply 51, a drive circuit 53, a target rotating speed detection module 54, an actual rotating speed detection module 55, a rotor position detection module 56, a current detection module 57, a motor 58 and a bus 59. The above components of this embodiment have the same or similar functions and structural compositions as those of the components of the foregoing embodiment shown in fig. 6, and are not described herein again, except that this embodiment adopts a more specific control module 50, which mainly includes: the circuit comprises a first rotating speed ring 501, a current distribution unit 502, a first current ring 503, a second current ring 504, a voltage conversion unit 505, a current conversion unit 507 and a PWM signal generation unit 506.
The first rotation speed loop 501 is connected to the target rotation speed detection module 54 and the actual rotation speed detection module 55, and the first rotation speed loop 501 acquires the target rotation speed n0 of the motor 58 set by the operation device 15 by the detected user setting from the target rotation speed detection module 54 and the actual rotation speed n of the motor 58 detected from the actual rotation speed detection module 55. The target rotation speed detection module 54 is connected to the operating device, and in the present embodiment, the target rotation speed detection module 54 is specifically arranged in association with the operating rod 151, and is used for detecting the position or the rotation angle of the operating rod 151. The target rotational speed detection module 54 may employ the position detection module 17 shown in fig. 2 and 4.
The first rotation speed loop 501 is used to generate a target current is0 according to a target rotation speed n0 and an actual rotation speed n of the motor 58. Specifically, the first rotation speed loop 501 can generate a target current is0 by comparison and adjustment according to the target rotation speed n0 and the actual rotation speed n of the motor 57, and the target current is0 is used to make the actual rotation speed n of the motor 57 approach the target rotation speed n 0. The first tacho ring comprises a comparing, regulating unit (not shown), which may be a PI regulating unit.
The current distribution unit 502 is connected to the first slew ring 501, and is configured to distribute a direct-axis target current id0 and a quadrature-axis target current iq0 according to a target current is 0.
Referring to fig. 9, the direct axis and the quadrature axis form a direct axis-quadrature axis coordinate system, the direct axis-quadrature axis coordinate system establishes a coordinate system on the motor rotor, the coordinate system rotates synchronously with the rotor, wherein the rotor magnetic field direction is the direct axis, the direction perpendicular to the rotor magnetic field direction is the quadrature axis, the direct axis target current id0 is in the same direction with the direct axis, the quadrature axis target current iq0 is in the same direction with the quadrature axis, and the quadrature axis target current iq0 is an excitation current for controlling a moment, and the moment perpendicular to the rotor is generated to drive the rotor to rotate. The quadrature target current iq0 can be used to control the motor speed to reach the target speed n0 of the motor 58 as quickly and stably as possible, and the principle is to control the electromagnetic torque of the motor by using the torque current so that the motor can drive the rotor to rotate to the maximum. The quadrature axis target current iq0 and the direct axis target current id0 may be obtained by calculation or may be set directly.
When a voltage is applied to the motor, a current can be generated in the stator, which causes the motor 58 to generate an electromagnetic torque Te. The electromagnetic torque Te of the motor can be obtained by the following formula:
Te＝1.5Pn[Ψf*iq0+(Ld-Lq)*id*iq]，
therein, ΨfIs rotor flux linkage, iq is quadrature axis current, id is direct axis current, Ld is direct axis inductance, Lq is quadrature axis inductance, PnIs the number of pole pairs.
As an embodiment of the motor, Ld ═ Lq, see fig. 9, where Te0 is 1.5Pn*ΨfIq 0. In order to obtain a large electromagnetic torque Te, the current distribution unit 502 makes the quadrature target current iq0 as large as possible. Since the quadrature axis target current iq0 and the direct axis target current iq0 are actually obtained by decoupling the target current is0 of the motor, if the quadrature axis target current iq0 is as large as possible, the direct axis target current iq0 should be as small as possible. As an embodiment, setting id0 ═ 0, the resulting stator flux linkage ΨsWith rotor flux linkage ΨfIs at an angle β of 90 (see fig. 9), such that by controlling the quadrature target current iq0, the torque is controlled, which produces a torque perpendicular to the rotor that causes the rotor to rotatesAssigning a sub-current to generate a flux linkage with the stator winding, the rotor flux linkage ΨfThe permanent magnet of the rotor generates magnetic flux and is linked with the stator winding to form a magnetic linkage.
As another embodiment of the motor, Ld < Lq, referring to fig. 10, if as large an electromagnetic torque Te as possible is to be obtained, it is necessary to make id0<0, where the direct axis target current id0 and the quadrature axis target current iq0 can be obtained according to the following formulas:
Figure BDA0002344452490000201
Figure BDA0002344452490000202
therein, ΨfIn order to rotate the rotor flux linkage, Lq and Ld are the inductances of the quadrature axis and the direct axis of the stator winding, respectively. is0 is a target current is0 generated by the first rotating speed ring 501 according to the target rotating speed n0 and the actual rotating speed n of the motor 58, the stator current space vector is0 is in phase with the stator flux linkage space vector Ψ s, and the stator flux linkage Ψ s issWith rotor flux linkage ΨfAngle β (see fig. 10).
Because the electromagnetic torque Te of the motor is 1.5Pn[Ψf*iq+(Ld-Lq)*id*iq]The formula includes two terms, the former 1.5PnΨfIq is the permanent magnet torque T1, fig. 11 curve T1; the latter 1.5Pn(Ld-Lq) × id × iq is reluctance torque T2, as shown in a curve T2 in fig. 11, and Te is synthesized by a curve T1 and a curve T2, it can be seen from fig. 11 that the synthesized electromagnetic torque Te has an approximate maximum value Tmax or a maximum value Tmax within a range of 90 ° to 135 ° of the corresponding torque angle, and therefore, the current distribution unit 502 may alternatively distribute the quadrature axis target current iq0 and the direct axis target current id0 so that an angle β between the stator flux linkage Ψ s and the rotor flux linkage Ψ f is within a range of 90 ° to 135 °, which may obtain as large an electromagnetic torque Te as possible, so that the actual torque of the motor 58 may reach the target torque as soon as possible, thereby increasing the torque corresponding speed of the motor 58, so that the rotational speed of the motor 58 may reach or substantially reach the target rotational speed n0 in a relatively fast time.
In summary, the control module 50 can control the currents loaded on the stator by controlling the three-phase voltages Uu, Uv and Uw loaded on the motor 58 according to the motor rotation speed, the motor current and the rotor position, so that the stator winding generates the stator current space vector is0, the stator current space vector is0 is in phase with the stator flux linkage space vector Ψ s, the stator current space vector is0 is the target current is0, the target current is0 can be distributed into the direct axis target current id0 and the quadrature axis target current iq0 by the current distribution unit 502, the control module 50 can control the quadrature axis current iq and the direct axis current id respectively, so as to control the included angle β between the stator flux linkage Ψ s and the rotor flux linkage Ψ f, so that the motor 58 can output the larger electromagnetic torque Te as much as possible, so that the actual torque of the motor 58 can reach the target torque as soon as possible, thereby increasing the corresponding speed of the torque of the motor 58, thereby enabling the motor 58 speed to reach or substantially reach the target speed n0 in a relatively rapid time.
The direct-axis target current id0 and the quadrature-axis target current iq0 distributed by the current distribution unit 502 according to the target current is0 can enable the rotor of the motor 58 to generate as large an electromagnetic torque Te as possible, so that the actual torque of the motor 58 can reach the target torque as soon as possible, and the rotating speed of the motor 58 can reach the target rotating speed n0 of the motor 58 set by the user through the operating device 15 as soon as possible, thereby improving the torque response speed and the rotating speed response speed of the motor 58.
The current conversion unit 507 obtains the three-phase currents iu, iv, iw, performs current conversion, and converts the three-phase currents iu, iv, iw into two-phase currents, which are the direct-axis actual current id and the quadrature-axis actual current iq, respectively. The current detection module 57 transmits the detected three-phase currents iu, iv, iw in the actual operation of the motor 58 to the current conversion unit 507 in the control module 50. Optionally, the current transformation unit 507 includes Park transformation and Clark transformation.
The first current loop 503 is connected to the current distribution unit 502 and the current transformation unit 507, obtains the direct-axis target current id0 and the direct-axis actual current id, and generates a first voltage adjustment quantity Ud according to the direct-axis target current id0 and the direct-axis actual current id, where the first voltage adjustment quantity Ud enables the direct-axis actual current id to approach the direct-axis target current id0 as soon as possible. The first current loop 503 includes a comparing and adjusting unit (not shown), which may be a PI adjustment, and the first current loop 503 includes comparing the direct-axis target current id0 and the direct-axis actual current id, and performing the PI adjustment according to the comparison result to generate the first voltage adjustment amount Ud.
The second current loop 504 is connected to the current distribution unit 502 and the current conversion unit 507 to obtain the quadrature axis target current iq0 and the quadrature axis actual current iq, and generates a second voltage adjustment amount Uq according to the quadrature axis target current iq0 and the quadrature axis actual current iq, where the second voltage adjustment amount Uq is used to make the quadrature axis actual current iq approach to the quadrature axis target current iq 0. The second current loop 504 includes a comparing and adjusting unit (not shown), which may be a PI adjustment, and the second current loop 504 includes comparing the quadrature target current iq0 and the quadrature actual current iq, and performing the PI adjustment according to the comparison result to generate a second voltage adjustment amount Uq.
The first voltage adjustment amount Ud and the second voltage adjustment amount Uq are converted into control signals for controlling the driving circuit 53 after some conversion and calculation. The first voltage regulating quantity Ud and the second voltage regulating quantity Uq are sent to the control signal generating unit for conversion, calculation and the like. In the present embodiment, the control signal generation unit includes a voltage conversion unit 505 and a PWM signal generation unit 506.
The voltage conversion unit 505 is connected to the first current loop 503 and the second current loop 504, and obtains a first voltage adjustment quantity Ud and a second voltage adjustment quantity Uq, and a position of a rotor of the motor 58 from the rotor position detection module 56, and can convert the first voltage adjustment quantity Ud and the second voltage adjustment quantity Uq into intermediate quantities Ua and Ub related to three-phase voltages Uu, Uv, and Uw applied to the motor 58 and output the intermediate quantities to the PWM signal generation unit 506, and the PWM signal generation unit 506 generates a PWM signal for controlling a switching element of the driving circuit 53 according to the intermediate quantities Ua and Ub, so that the power supply 51 can output three-phase voltages Uu, Uv, and Uw applied to a winding of the motor 58, the Uu, Uv, and Uw are three-phase symmetrical sine wave voltages or saddle wave voltages, and the three-phase voltages Uu, Uv, and Uw mutually form a phase difference of 120 °. Optionally, the voltage transforming unit 505 comprises Park inverse transformation and Clark inverse transformation.
With the control module 50, the present embodiment adopts the following control method:
the current conversion unit 507 obtains the three-phase currents iu, iv, iw detected by the current detection module 57 and the rotor position information of the rotor position detection module 56, performs current conversion, and converts the three-phase currents iu, iv, iw into two-phase currents, which are the direct-axis actual current id and the quadrature-axis actual current iq, respectively. The first current loop 503 acquires the direct-axis target current id0 and the direct-axis actual current id, and generates a first voltage adjustment quantity Ud according to the direct-axis target current id0 and the quadrature-axis actual current id. The second current loop 504 obtains the quadrature target current iq0 and the direct actual current iq, and generates a second voltage adjustment amount Uq according to the quadrature target current iq0 and the quadrature actual current iq. The voltage conversion unit 505 acquires the first voltage adjustment amount Ud and the second voltage adjustment amount Uq and the rotor position of the rotor position detection module 56, and converts the first voltage adjustment amount Ud and the second voltage adjustment amount Uq into intermediate amounts Ua and Ub related to the three-phase voltages Uu, Uv, and Uw applied to the motor 58 to output to the PWM signal generation unit 506, and the PWM signal generation unit 506 generates a PWM signal for controlling the switching elements of the drive circuit 53 according to the intermediate amounts Ua and Ub, so that the power supply 51 outputs the three-phase voltages Uu, Uv, and Uw applied to the windings of the motor 58. Referring to fig. 15 and 16, in the present embodiment, the three-phase voltages Uu, Uv, and Uw are three-phase symmetrical sine wave voltages (fig. 15) or saddle wave voltages (fig. 16), and the three-phase voltages Uu, Uv, uwu, Uv, and Uw are 120 ° out of phase with each other.
In this process, the control module 50 outputs a control signal that varies with the rotor position change to dynamically adjust and control the voltage and/or current applied to the motor such that the motor 58 can obtain as large an electromagnetic torque as possible at each rotor position, so that the rotational speed of the motor 58 can reach the target rotational speed n0 of the motor 58 set by the user via the operating device 15 as quickly as possible, thereby increasing the response speed of the motor 58. In contrast to prior art riding lawn mowers 10, the riding lawn mower 10 of the present invention may have a response speed of the first motor 143 to output torque within 100ms, and in some embodiments, a response speed of the first motor 143 to output torque within 80 ms. In some embodiments, the predetermined time is less than the response speed of the first motor 143 to output torque by 50 ms. In some embodiments, the first motor 143 outputs torque with a response speed within 20 ms.
Accordingly, the actual rotational speed of the first motor 143 can reach or substantially reach the target rotational speed in a relatively short time. Optionally, the actual rotation speed of the first motor 143 reaches or substantially reaches the target rotation speed within a second preset time, and the second preset time is less than 800 ms. In some embodiments, the second preset time is less than 600 ms. In some embodiments, the second preset time is less than 300 ms.
Alternatively, the present invention can further increase the motor response speed of the riding mower 10 of the present invention by using the bus 59 and the target rotation speed detection module 54, and can make the response speed of the output torque of the first motor 143 within 10 ms.
Optionally, the communication frame rate of the bus may range from 100Hz to 2000 Hz. Optionally, the communication frame rate of the bus is in a range of 200Hz to 2000 Hz. Optionally, the communication frame rate of the bus is in a range of 300Hz to 3000 Hz.
In some embodiments, the communication frame rate of the bus is in a range of 100Hz to 1000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 200Hz to 800 Hz. In some embodiments, the communication frame rate of the bus is in a range of 100Hz to 500 Hz. In some embodiments, the bus has a communication frame rate in a range of 500Hz to 1000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 500Hz to 1500 Hz. In some embodiments, the communication frame rate of the bus is in a range of 1000Hz to 2000 Hz. In some embodiments, the communication frame rate of the bus is in a range of 1000Hz to 1500 Hz. The frame rate of the bus 59 refers to the number of times the bus receives and/or transmits packets in one second.
The target speed detection module 54 includes a sensor having a sensor data refresh rate in a range of 50 microseconds/time to 10 milliseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 50 microseconds/time to 200 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 300 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 200 microseconds/time to 500 microseconds/time. In some embodiments, the data refresh rate of the sensor ranges from 100 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 500 microseconds/time to 1 millisecond/time. In some embodiments, the data refresh rate of the sensor ranges from 1 ms/time to 10 ms/time.
Of course, in some other embodiments, the bus 59 may not be used, the control module 50 and the target rotation speed detection module 54 are connected by a common connection line, and the target rotation speed detection module 54 uses a sensor with the data refresh rate, so that the actual torque of the first motor reaches or substantially reaches the target torque within a first preset time, which is less than 60 ms.
In other embodiments, the target speed detection module 54 uses a sensor with a normal data refresh rate, and the bus 59 uses a bus with the above communication frame rate, so that the actual torque of the first motor can reach or substantially reach the target torque within a first preset time, which is less than 60ms, by using the above control method.
Referring to fig. 12, as a more specific embodiment of another control system of the first motor 143, the control system includes: the device comprises a control module 60, a power supply 61, a driving circuit 63, a target rotating speed detection module 64, an actual rotating speed detection module 65, a rotor position detection module 66, a current detection module 67, a motor 68 and a bus 69. The above components of this embodiment have the same or similar functions and structural compositions as those of the components of the foregoing embodiment shown in fig. 10, and are not described again here, except that another more specific control module 60 is adopted in this embodiment, where the control module 60 includes: the device comprises a second rotating speed ring 601, a current distribution unit 602, a target flux linkage calculation unit 603, a torque ring 604, a flux linkage ring 605, a feedback linearization control unit 606, a voltage conversion unit 607, a PWM signal generation unit 608, a current conversion unit 609 and a torque and flux linkage calculation unit 610.
The second rotation speed loop 601 is connected to the target rotation speed detection module 64 and the actual rotation speed detection module 65, and the second rotation speed loop 601 obtains the target rotation speed n0 of the motor 68 set by the operation device 15 from the detected user setting of the target rotation speed detection module 64 and the actual rotation speed n of the motor 68 from the actual rotation speed detection module 65. The target rotation speed detection module 64 is connected to the operating device, and in the present embodiment, the target rotation speed detection module 64 is specifically arranged in association with the operating rod 151 and is used for detecting the position or the rotation angle of the operating rod 151. The target rotational speed detection module 64 may employ the position detection module 17 shown in fig. 2 and 4.
The second speed loop 601 is used for generating a target torque Te0 according to the target speed n0 and the actual speed n of the motor 68, wherein the target torque Te0 is an electromagnetic torque Te 0. Specifically, the second rotation speed loop 601 can generate a target torque Te0 by comparison and adjustment according to the target rotation speed n0 and the actual rotation speed n of the motor 68, the target torque Te0 being used to cause the actual rotation speed n to approach the target rotation speed n0 as quickly as possible. The second speed loop 601 comprises a comparison and regulation unit (not shown), which may be a PI regulation unit.
The current distribution unit 602 distributes the direct-axis target current id0 and the quadrature-axis target current iq0 according to the output target torque Te 0. Referring to fig. 13, the direct axis target current id0 and the quadrature axis target current iq0 are vectors having directions and magnitudes, and the electrical angle between the direct axis target current id0 and the quadrature axis target current iq0 is 90 °, and the direct axis target current id0 and the quadrature axis target current iq0 are located on the direct axis and the quadrature axis, respectively. Alternatively, the direct axis target current id0 and the quadrature axis target current iq0 may be obtained according to the following formulas:
Figure BDA0002344452490000251
Figure BDA0002344452490000252
Figure BDA0002344452490000253
the method comprises the following steps that psi f is a rotor flux linkage, psi s is a stator flux linkage, Lq and Ld are respectively the inductances of a quadrature axis and a direct axis of a stator winding, and Pn is a magnetic pole pair number.
The target flux linkage calculation unit 603 can calculate the target stator flux linkage Ψ s0 from the direct-axis target current id0 and the quadrature-axis target current iq 0. In this way, the control module 73 can directly and dynamically adjust the stator flux linkage Ψ s and the electromagnetic torque Te0 so that the motor speed can reach or substantially reach the target speed within a preset time frame. Of course, the target stator flux linkage Ψ s0 may be obtained by other methods, and is not limited to the calculation performed by the target flux linkage calculation unit 603 according to the present embodiment based on the direct-axis target current id0 and the quadrature-axis target current iq 0.
Optionally, the control module 73 controls an included angle β between the stator flux linkage Ψ s and the rotor flux linkage Ψ f to be 90 °; alternatively, the control module 73 controls the included angle β between the stator flux linkage Ψ s and the rotor flux linkage Ψ f to be between 90 ° and 135 ° (refer to fig. 13), in such a way that the motor 68 can obtain a large electromagnetic torque Te, so that the actual rotation speed of the motor 68 can reach or substantially reach the target rotation speed within a preset time range.
Next, the target stator flux linkage Ψ s0 and the target torque Te0 need to be compared with the actual stator flux linkage Ψ s and the actual torque Te and adjusted to generate a control signal to adjust the actual stator flux linkage Ψ s and the actual torque Te, so that the actual stator flux linkage Ψ s and the actual torque Te can reach the target stator flux linkage Ψ s0 and the target torque Te0 as soon as possible.
Specifically, the current conversion unit 609 acquires the detected three-phase currents iu, iv, iw of the current detection module 67 and the position θ of the rotor of the output of the rotor position detection module 66, converts the three-phase currents iu, iv, iw into two-phase actual currents, a direct-axis actual current id and a quadrature-axis actual current iq, respectively, which are vectors having directions and magnitudes, and the directions of the direct-axis actual current id and the quadrature-axis actual current iq are perpendicular to each other.
The torque and flux linkage calculation unit 610 acquires the direct-axis actual current id and the quadrature-axis actual current iq from the current conversion unit 609, and generates the actual torque Te and the actual stator flux linkage Ψ s from the direct-axis actual current id and the quadrature-axis actual current iq. The actual torque Te is output to the torque ring 604 and the actual flux linkage Ψ s is output to the flux linkage 605. In other embodiments, the actual torque Te and the actual stator flux linkage Ψ s may also be obtained by direct detection.
The torque loop 604 acquires the actual torque Te calculated by the torque and flux linkage calculating unit 610 and the target torque Te0 output by the rotation speed loop 610, and generates the first adjustment amount v1 from the actual torque Te and the target torque Te 0. The first adjustment amount v1 is used to compensate the actual torque Te so that the actual torque Te approaches the target torque Te 0. The torque loop 604 comprises a comparison and adjustment unit, optionally a PI adjustment, the torque loop 604 comparing the actual torque Te with the target torque Te0 and performing the PI adjustment to obtain the first adjustment amount v 1.
The magnetic chain ring 605 acquires the actual stator flux linkage Ψ s calculated by the torque and flux linkage calculation unit and the target stator flux linkage Ψ s0 generated by the target flux linkage calculation unit 603, and generates a second adjustment amount v2 according to the actual stator flux linkage Ψ s and the target stator flux linkage Ψ s 0. The second adjustment amount v2 is used to compensate the actual stator flux linkage Ψ s so that the actual stator flux linkage Ψ s approaches the target stator flux linkage Ψ s 0. The magnetic chain loop 605 comprises a comparing and adjusting unit, optionally the adjusting unit comprises a PI adjustment, the magnetic chain loop 605 compares the actual stator flux linkage Ψ s and the target stator flux linkage Ψ s0, and the PI adjustment is performed to obtain a second adjustment amount v 2.
The first adjustment amount v1 and the second adjustment amount v2 need to be converted into control signals for controlling the drive circuit 63 after being converted and calculated. The first adjustment amount v1 and the second adjustment amount v2 are input to the control signal generation unit, which in this embodiment optionally includes a feedback linearization control unit 606, a voltage conversion unit 607, and a PWM signal generation unit 608.
The feedback linearization control unit 606 generates the voltage control amount Uq and the voltage control amount Ud in the orthogonal coordinate system from the first adjustment amount v1 generated by the torque loop 604, the second adjustment amount v2 generated by the flux loop 605, and the orthogonal component Ψ d and the orthogonal component Ψ q of the actual stator flux Ψ s generated by the torque and flux calculation unit 610, and from v1, v2, Ψ d, Ψ q.
The voltage conversion unit 607 acquires the voltage controlled quantity Uq and the second voltage controlled quantity Ud, and converts the voltage controlled quantity Uq and the voltage controlled quantity Ud into the voltage controlled quantity ua and the voltage controlled quantity U β in the α - β coordinate system.
The PWM signal generating unit 608 generates PWM control signals for controlling the driving circuit 63 according to the voltage control amount U α and the voltage control amount U β in a α - β coordinate system, so that the power supply 61 outputs three-phase voltages Uu, Uv and Uw to be loaded to windings of the motor 68, in the embodiment, the Uu, Uv and Uw are three-phase symmetrical sine wave voltages or saddle wave voltages, and the Uu, Uv and Uw are 120-degree phase difference with each otherfThe included angle between them is 90 deg.. Alternatively, the three phases Uu, Uv, Uw applied to the electric machine 68 are such that the stator flux linkage Ψ s0 and the rotor flux linkage ΨfThe included angle between the two is in the range of 90 degrees to 135 degrees.
In this way, the torque control is directly performed according to the actual feedback electromagnetic torque Te and the stator flux linkage Ψ s, so that the motor can obtain a faster torque response speed. In the present embodiment, an error obtained by comparing a predetermined target torque with an actual torque and an error obtained by comparing a predetermined target stator flux with an actual stator flux are used to select an appropriate voltage vector for control, and since the control effect of the present embodiment is determined by the actual torque condition by directly comparing the predetermined torque with the actual torque, a relatively rapid torque response can be obtained, and the response speed of the output torque of the first motor 143 can be made within 100ms by the riding mower 10 of the present invention.
Alternatively, the present invention can further increase the motor response speed of the riding mower 10 of the present invention by using the bus 69 and the target rotation speed detection module 64, and the response speed of the output torque of the first motor 143 can be within 10 ms. The bus 69 and the target rotational speed detection module 64 are the same as the bus 59 and the target rotational speed detection module 54 in the foregoing embodiment.
In the two embodiments, different control methods are respectively used, so that the motor can obtain a quicker torque response, and the output torque response speed of the motor is increased, so that the actual torque of the first motor reaches or substantially reaches the target torque within a first preset time, the first preset time is less than 100ms, the actual rotating speed of the first motor reaches or substantially reaches the target rotating speed within a second preset time, and the second preset time is less than 800 ms.
In this embodiment, the control signal output by the control module (30, 50, 60) to the drive circuit (33, 53, 63) is a control signal that varies with the change in the rotor position of the motor (38, 58, 68) such that the input voltage and/or current to the motor (38, 58, 68) varies with the change in the rotor position, the input voltage and/or current to the motor (38, 58, 68) varies in a sine wave or saddle wave manner such that the motor has continuous, alternating current states on the three-phase stator windings during at least one electrical cycle or part of an electrical cycle, the current states on the three-phase stator windings capable of synthesizing vector moments that move approximately continuously along a circumference, the rotor of the motor rotating synchronously with the vector moments that move approximately continuously along the circumference, as compared to the conventional square wave control, with only 6 discrete square wave control modes, The invention can improve the motor driving efficiency and the motor response speed in a discontinuous driving state. In the invention, the control module outputs a control signal to the drive circuit to enable the input current or the input voltage of the first motor to change along with the position change of the rotor of the first motor, so that the actual rotating speed of the first motor reaches or basically reaches the target rotating speed within a preset time, and the preset time is less than 100 ms.
Further, by using the buses (59, 69) and the target rotation speed detection modules (54, 64), the response speed of the motor of the riding mower 10 of the present invention can be further increased, and the response speed of the output torque of the first motor 143 can be set to be within 10 ms.
In the above embodiment, the position of the operation lever 151 corresponds to the speed of the first motor 143. When the user pushes the operation lever 151, the target rotation speed detection module (54, 64) corresponding to the operation lever 151 outputs a detection signal corresponding to the current position of the operation lever 151 to the control module (30, 50, 60). After receiving the detection signal, the control module 30 obtains the target rotation speed of the first motor 151 corresponding to the operation rod 151 through table lookup or calculation according to the detection signal. In addition, the actual rotation speed detection module (55, 65) feeds back a detection signal about the actual rotation speed of the first motor 143 detected by the control module (50, 60), the control module (50, 60) obtains the actual rotation speed of the first motor 143 according to the detection signal, the control module (50, 60) compares the obtained actual rotation speed of the first motor 143 with the target rotation speed to obtain an error, and according to the obtained error, the first motor 143 can reach or substantially reach the target rotation speed set by the user through the operation rod 151 by controlling the quadrature axis and direct axis current vectors or by controlling the stator flux linkage and the torque. The process control module (50, 60) continuously compares the target rotation speed of the first motor 143 with the actual rotation speed, and by using the two controllers (50, 60) and the corresponding control processes, the first motor 143 can reach or substantially reach the target rotation speed set by the user through the operation rod 151 within a preset time in a short time.
In one embodiment, a dead zone interval exists between the operating position of the operating device 15 and the target rotational speed of the first motor, in which the target rotational speed of the first motor 143 is constant. Referring to fig. 14, in the case of the operating device 15 shown in fig. 2 to 4, the target rotational speed n0 of the first motor 143 is proportional to the operating position (e.g., the angular position P) of the operating lever 151, and a dead zone (e.g., a broken line in fig. 14(a) near the zero operating position) is provided near the zero angular position of the angular position P of the operating lever 151, in which the target rotational speed of the first motor 143 is constant.
The dead zone section represents: the target rotation speed of the first motor 143 is not changed until the operating lever 151 is pushed to the certain angular position Pa from the beginning, and optionally, the target rotation speed of the first motor 143 is zero at this time, so that it is possible to prevent a safety accident due to malfunction of the first motor 143 caused by some shaking. Outside the dead band interval, it can be considered that the position of the operation lever 151 at a certain angular position represents a certain target rotation speed n0 of the first motor 143.
In addition, referring to fig. 14 (c), in order to prevent the user from accidentally pushing the operating lever 143 beyond the allowable angle range, the first motor 143 is provided with the maximum output torque TM. When Pa is set at a certain angular position of the operating lever 151, the target rotation speed n0 and the maximum output torque TM of the first motor 143 can be determined. That is, when the target rotation speed is set, the control lever 151 also sets a target torque that can be used to bring the first motor 143 to the target rotation speed as soon as possible.
As shown in fig. 14 (b), the torque T of the output of the first motor 143 varies in a curve with the actual rotation speed n of the first motor 143, and when the actual rotation speed n of the first motor 143 is less than the target rotation speed n0, the torque of the output of the first motor should be increased so that the first motor 143 is accelerated, but the increased torque should not exceed the maximum torque value TM that defines the output of the first motor 143 at that angle; similarly, if the actual speed n of the first motor 143 is greater than the target speed n0, the output torque T should be decreased to decelerate the first motor 143; if the actual speed n of the first motor 143 is equal to the target speed n0, the output torque Ta of the first motor 143 is zero.
The dead zone section reduces the response speed of the first motor 143, and according to the present invention, the response speed of the first motor 143 for outputting the torque can be set within 100ms even if the dead zone section is provided.
Of course, the operation device of the riding mower 10 according to the above embodiment is not limited to the operation device 15 including the operation lever 151 provided on each of the left and right sides in the above embodiment, and other operation devices may be used, for example, the operation device 75 of the riding mower 70 shown in fig. 17, and the operation device 75 including the steering wheel 751 and the speed lever 752 (accelerator) can also achieve a response speed of the motor output torque within 100ms, preferably within 40 ms. Optionally, the steering wheel 751 is an electronic steering wheel.
Other components of the vehicle row mower 70 include: frame 71, seat 72, power take-off assembly 73, walking assembly 74, operating device 75, power supply device 76. The frame 71, the seat 72, the power output assembly 73, the walking assembly 74, and the power supply device 76 are identical or similar to the riding mower 10 of the previous embodiment in structure and function, and will not be described again. The difference is in the operating means. The operating device 75 of the vehicle lawnmower 70 employs a combination of a steering wheel 751 and a speed lever 752 (throttle), and distributes the speeds of the left and right motors by the angle of rotation of the steering wheel 751 and a given speed of the speed lever to control the traveling of the first traveling wheel 741. Similar to the above embodiment, the target speed is determined by the position of the speed lever 752 (throttle), the target speed is compared with the actual speed, and the two controllers and control methods in the above embodiment are adopted to realize that the actual speed of the motor quickly reaches the target speed set by the speed lever 151, so as to improve the corresponding speed of the motor, thereby improving the user experience and the safety of the riding mower.
While the principles, features and advantages of the present invention have been shown and described, it is not intended to be limited to the specific embodiments, but rather, it is to be understood that various combinations of the components of the embodiments may be utilized to form different embodiments, and equivalents or changes may be made without departing from the scope of the present invention.

Claims (10)

1. A riding lawn mower comprising:
the walking assembly comprises a walking wheel and a first motor for driving the walking wheel to walk, wherein the first motor comprises a stator, a rotor and a stator winding;
a power take off assembly including a blade for mowing and a second motor driving the blade;
a power supply device at least for supplying electric energy to the first motor;
a drive circuit for loading electric energy of the power supply device to the first motor;
an operating device for setting at least one of a target torque and a target rotational speed of the first motor;
and the control module is used for outputting a control signal to the driving circuit to enable the input current or the input voltage of the first motor to change along with the position change of the rotor of the first motor, so that the actual torque of the first motor reaches or basically reaches the target torque within a first preset time, and the first preset time is less than 100 ms.
2. The riding lawn mower of claim 1,
the actual rotating speed of the first motor reaches or basically reaches the target rotating speed within a second preset time, and the second preset time is less than 800 ms.
3. The riding lawn mower of claim 1,
further comprising:
and the target rotating speed detection module is connected with the operating device in an associated manner and is used for detecting the target rotating speed of the first motor set by the operating device.
4. The riding lawn mower of claim 3,
the target rotating speed detection module is connected with the control module through a bus, and the communication frame rate of the bus ranges from 100Hz to 3000 Hz.
5. The riding lawn mower of claim 1,
and the included angle between the stator flux linkage and the rotor flux linkage of the first motor is in the range of 90-135 degrees.
6. The riding lawn mower of claim 1,
the input voltage of the first motor is changed in a sine wave or saddle wave manner, and the input current of the first motor is changed in a sine wave manner.
7. The riding lawn mower of claim 1,
the control module includes:
a first rotating speed ring for generating a target current of the first motor according to a target rotating speed and an actual rotating speed of the first motor.
8. The riding lawn mower of claim 7,
the control module further comprises:
a current distribution unit for distributing a direct axis target current and a quadrature axis target current according to the target current of the first motor generated by the first rotation ring;
the current conversion unit is used for generating a direct-axis actual current and a quadrature-axis actual current according to the actual current of the first motor and the rotor position of the first motor;
the first current loop is used for generating a first voltage regulating quantity according to the direct-axis target current and the direct-axis actual current;
the second current loop is used for generating a second voltage regulating quantity according to the quadrature axis target current and the quadrature axis actual current;
and the control signal generating unit is used for generating a control signal according to the first voltage regulating quantity and the second voltage regulating quantity, and the control signal is used for controlling the driving circuit.
9. The riding lawn mower of claim 1,
the control module includes:
a second rotation speed ring for generating the target torque of the first motor according to a target rotation speed and an actual rotation speed of the first motor.
10. The riding lawn mower of claim 9,
the control module further comprises:
a torque loop for generating a first adjustment amount according to a target torque and an actual torque of the first motor;
a magnetic chain loop for generating a second adjustment amount according to a target stator flux linkage and an actual stator flux linkage of the first motor;
and the control signal generating unit is used for generating a control signal according to the first regulating quantity and the second regulating quantity, and the control signal is used for controlling the driving circuit.
CN201911389143.5A 2019-03-28 2019-12-30 Riding type mower Pending CN111756280A (en)

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EP20827316.9A EP3979488B1 (en) 2019-06-21 2020-06-19 Ride-on lawnmower
US17/556,049 US11999240B2 (en) 2019-12-30 2021-12-20 Riding lawn mower

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114408039A (en) * 2022-02-21 2022-04-29 浙江工业大学之江学院 Electric mud flat vehicle with double-drive type control system and convenient for automatic control
CN114868513A (en) * 2021-02-05 2022-08-09 米沃奇电动工具公司 Non-contact switch for lawn mower
WO2023020206A1 (en) * 2021-08-16 2023-02-23 余姚市爱优特电机有限公司 Rolling vehicle
WO2023044767A1 (en) * 2021-09-24 2023-03-30 Nanjing Chervon Industry Co., Ltd. Riding lawn mower
WO2023060562A1 (en) * 2021-10-15 2023-04-20 Nanjing Chervon Industry Co., Ltd. Riding lawn mower
WO2023071515A1 (en) * 2021-10-29 2023-05-04 南京泉峰科技有限公司 Self-propelled working machine and lawn mower
WO2023246372A1 (en) * 2022-06-23 2023-12-28 南京泉峰科技有限公司 Electric tool and control method
US11890741B2 (en) 2019-05-13 2024-02-06 Milwaukee Electric Tool Corporation Contactless trigger with rotational magnetic sensor for a power tool

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103401493A (en) * 2013-08-09 2013-11-20 固高科技(深圳)有限公司 Control system and method for permanent magnet synchronous electric spindle driving
CN107154763A (en) * 2017-05-27 2017-09-12 东南大学 Permagnetic synchronous motor dead beat direct Torque Control and control method
CN107371562A (en) * 2016-05-16 2017-11-24 南京德朔实业有限公司 Power tool, hay mover and its control method
CN208159349U (en) * 2018-04-13 2018-11-30 宁波朗辉工具有限公司 A kind of Straddle riding type grass trimmer gear adjusting mechanism

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103401493A (en) * 2013-08-09 2013-11-20 固高科技(深圳)有限公司 Control system and method for permanent magnet synchronous electric spindle driving
CN107371562A (en) * 2016-05-16 2017-11-24 南京德朔实业有限公司 Power tool, hay mover and its control method
CN107154763A (en) * 2017-05-27 2017-09-12 东南大学 Permagnetic synchronous motor dead beat direct Torque Control and control method
CN208159349U (en) * 2018-04-13 2018-11-30 宁波朗辉工具有限公司 A kind of Straddle riding type grass trimmer gear adjusting mechanism

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11890741B2 (en) 2019-05-13 2024-02-06 Milwaukee Electric Tool Corporation Contactless trigger with rotational magnetic sensor for a power tool
CN114868513A (en) * 2021-02-05 2022-08-09 米沃奇电动工具公司 Non-contact switch for lawn mower
WO2023020206A1 (en) * 2021-08-16 2023-02-23 余姚市爱优特电机有限公司 Rolling vehicle
WO2023044767A1 (en) * 2021-09-24 2023-03-30 Nanjing Chervon Industry Co., Ltd. Riding lawn mower
EP4231814A4 (en) * 2021-09-24 2023-12-13 Nanjing Chervon Industry Co., Ltd. Riding lawn mower
WO2023060562A1 (en) * 2021-10-15 2023-04-20 Nanjing Chervon Industry Co., Ltd. Riding lawn mower
WO2023071515A1 (en) * 2021-10-29 2023-05-04 南京泉峰科技有限公司 Self-propelled working machine and lawn mower
CN114408039A (en) * 2022-02-21 2022-04-29 浙江工业大学之江学院 Electric mud flat vehicle with double-drive type control system and convenient for automatic control
WO2023246372A1 (en) * 2022-06-23 2023-12-28 南京泉峰科技有限公司 Electric tool and control method

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