A safety control method based on motor ramp shutdown

Abstract

The present invention relates to a safety control method for shutdown of a motor on a ramp. The present invention adopts a safety control method for shutdown of a motor on a ramp, comprising the following steps: S1. The motor receives a shutdown command; S2. After the drive control module receives the shutdown command, it detects whether the motor is on a ramp; S3. When it is determined that the motor is not on a ramp, the remote control module and the drive control module are directly shut down; when it is determined that the motor is on a ramp, the ramp shutdown process is executed; in the ramp shutdown process of step S3, after the drive control module receives the shutdown command, the remote control module is shut down to enable the motor to generate a reverse torque of the required value; after the remote control module is shut down for the first set time, the drive control module controls the motor to stop generating a reverse torque, and the motor actively short-circuits. The present invention enables the drive control module to control the motor to output a reverse torque, thereby avoiding the scooter or wheelchair with a motor from walking on a ramp, so that there is no need to set an electromagnetic brake on the motor.

Description

Technical Field

[0001] The invention relates to a safety control method based on motor ramp shutdown. Background Art

[0002] The motors of slow-speed mobility tools such as scooters and wheelchairs are usually equipped with brakes. If mechanical brakes are used, manual braking operation is required after the scooter / wheelchair is shut down on a slope. Scooters / wheelchairs are usually suitable for elderly people with limited behavioral abilities. Some users may need a long time to complete the braking action, and the risk of shutting down on a slope is high. Therefore, scooters / wheelchairs often use electromagnetic brakes.

[0003] However, when a scooter / wheelchair using electromagnetic brakes is in normal driving, the electromagnetic brakes are always powered on, which will result in high energy consumption during driving of the scooter / wheelchair, requiring the use of larger batteries, or limiting the driving range. At the same time, the setting of electromagnetic brakes will increase the weight of the entire scooter / wheelchair, which will not only affect the lightweight of the scooter / wheelchair, but also increase the assembly process. Summary of the invention

[0004] The object of the present invention is to provide a motor ramp shutdown safety control method which can make a mobility scooter / wheelchair lighter, more convenient to produce and assemble, and can extend the travel range.

[0005] To achieve the above object, the present invention adopts a motor ramp shutdown safety control method, which includes the following steps:

[0006] S1. The motor receives a shutdown command;

[0007] S2. After receiving the shutdown command, the drive control module detects whether the motor is on the slope;

[0008] S3. When it is determined that the motor is not on the ramp, the remote control module and the drive control module are directly shut down;

[0009] When it is determined that the motor is on a slope, the slope shutdown process is executed;

[0010] In the ramp shutdown process of step S3, after the drive control module receives the shutdown command, the remote control module shuts down, and the drive control module calculates the first brake torque output value PWM1 required for the motor to generate a reverse torque according to the angular velocity and moving distance of the wheel during rotation, and outputs PWM1 to the motor drive to enable the motor to generate the required reverse torque;

[0011] When the remote control module is turned off for a first set time, the drive control module controls the motor to stop generating reverse torque, and the motor actively short-circuits.

[0012] The solution of the present invention enables the drive control module to control the motor to output a reverse torque, thereby preventing the scooter / wheelchair from rolling on a slope to achieve a braking function, thereby eliminating the need to provide an electromagnetic brake on the scooter / wheelchair, reducing the production and assembly processes, and reducing the weight of the scooter / wheelchair to achieve lightweight. At the same time, the scooter / wheelchair does not need to keep the electromagnetic brake working all the time when in use, thereby reducing energy consumption and extending the travel of the scooter / wheelchair.

[0013] By actively short-circuiting the motor, the scooter / wheelchair with the motor can slowly roll down a slope, thereby preventing the scooter / wheelchair with the motor from quickly rolling down a slope under its own weight after running out of power, thereby improving safety in use and ensuring that the scooter / wheelchair still has power after moving to flat ground.

[0014] Preferably, in step S2, the magnitude relationship between the current I of the motor and the minimum current I_limit when the motor is working is compared. If I>I_limit, it means that the motor is located on a slope.

[0015] Preferably, in step S2, the magnitude relationship between the second braking torque output value PWM2 of the motor on the ramp and Pwm_limit is compared, where Pwm_limit is the minimum braking torque output value of the motor when judging whether the motor is on the ramp; when PWM2<-Pwm_limit, it is judged that the motor is on the downhill ramp, and when PWM2>Pwm_limit, it is judged that the motor is on the uphill ramp. After mutual verification, the detection accuracy can be higher.

[0016] Preferably, in step S2, when the motor is a hub motor, the PWM2 of all motors is detected, and the size relationship between the PWM2 of all motors and Pwm_limit is compared. When the PWM2 of all motors is less than -Pwm_limit, it is judged that the motor is on a downhill slope; when the PWM2 of all motors is greater than Pwm_limit, it is judged that the motor is on an uphill slope.

[0017] Preferably, in step S3, if it is determined that the mobility scooter / wheelchair is on a slope, the drive control module sends an instruction to the remote control module, and the remote control module sends an alarm signal. After the shutdown button is pressed again, the remote control module shuts down.

[0018] Preferably, in step S3, the motor is actively short-circuited by switching to short-circuiting the lower three tubes of the MOS of the drive control module. After the lower three tubes of the MOS are short-circuited, the three phases are short-circuited, the motor is switched to the power generation mode, and the movement direction of the motor rotor is opposite to the direction of the rotor rotating and cutting the magnetic field during normal walking, so that the motor rotor has resistance to rotation, thereby achieving slow walking down.

[0019] Preferably, in step S3, the drive control module shuts down after the motor actively short-circuits for a second set time, or after it is detected that the motor is on flat ground for a third set time, and after the motor actively short-circuits for a fourth set time.

[0020] As a preferred method, the calculation formula of PWM1 is as follows:

[0021] PWM1=-Kp*Pos+SumI;

[0022] SumI 后 =SumI 前 +(-Spd*ki);

[0023] Among them, Kp is the moving distance adjustment parameter, Pos is the moving distance, which is positive when moving forward and negative when moving backward; SumI is the speed adjustment integral value, Spd is the rotation speed, which is positive when moving forward and negative when moving backward, and ki is the adjustment ratio; if Spd*SumI>0, SumI=0, the purpose is to prevent the integral of the speed from being in the same direction as the speed, generating a torque in the same direction as the movement.

[0024] The present invention enables the driving control module to control the motor to output a reverse torque, thereby preventing the scooter or wheelchair with a motor from rolling on a slope to achieve a braking function, thereby eliminating the need to provide an electromagnetic brake on the motor. This has the advantages of reducing production and assembly processes, reducing the weight of the scooter / wheelchair to achieve lightweighting, and at the same time, the scooter / wheelchair does not need to have the electromagnetic brake working all the time when in use, thereby reducing energy consumption to extend the travel of the scooter / wheelchair. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure is a control principle flow chart of the present invention.

[0026] Figure 2 This is the control schematic diagram when the three lower circuits of the motor are short-circuited. DETAILED DESCRIPTION

[0027] The present invention will be further described below based on the accompanying drawings and specific embodiments.

[0028] Depend on Figure 1 As shown, this embodiment discloses a safety control method based on motor ramp shutdown, comprising the following steps:

[0029] S1. Press the shutdown button, and the remote control module receives the shutdown command and sends it to the drive control module through the serial communication protocol. The drive control module controls the motor to output a torque opposite to the direction of the wheelchair movement (slip), so that the wheels at the motor rotate, thereby realizing electronic braking.

[0030] S2. After receiving the shutdown command, the drive control module detects whether the scooter / wheelchair is on a ramp. Compare the magnitude relationship between the current I of the two wheel hub motors of the scooter / wheelchair and the minimum current I_limit when the motor is working. If I>I_limit, it means that the scooter / wheelchair is on a ramp. The larger the current, the greater the force received by the scooter / wheelchair in the parking state, which is further deduced to be the larger the ramp.

[0031] At the same time, the magnitude relationship between the second brake torque output value PWM2 of the scooter / wheelchair on the ramp and Pwm_limit is compared. Pwm_limit is the minimum brake torque output value of the motor when judging whether the scooter / wheelchair is on a ramp; when PWM2<-Pwm_limit, it is judged that the scooter / wheelchair is on a downhill ramp, and when PWM2>Pwm_limit, it is judged that the scooter / wheelchair is on an uphill ramp. Among them, PWM2 is a negative value, which means that the force provided by the motor is negative, further indicating that it is in a downhill state at this time, and vice versa, it is in an uphill state.

[0032] S3. If it is determined that the scooter / wheelchair is not on the ramp, the remote control module and the drive control module are directly shut down; if it is determined that the scooter / wheelchair is on the ramp, the ramp shutdown process is executed.

[0033] In the ramp shutdown process, if it is determined that the scooter / wheelchair is on a ramp, the drive control module sends an instruction to the remote control module, and the remote control module sends an alarm signal. The alarm signal includes a voice message "long press again to shut down". After the user presses the power off button again, the remote control module shuts down. At the same time, the drive control module calculates the first braking torque output value PWM1 required for the motor to generate a reverse torque based on the angular velocity and moving distance of the wheel rotation, and outputs PWM1 to the motor drive to make the motor generate the required reverse torque, thereby preventing the scooter / wheelchair from rolling down the slope.

[0034] Among them, PWM1=-Kp*Pos+SumI; SumI 后 =SumI 前 +(-Spd*ki); Kp is the moving distance adjustment parameter, Pos is the moving distance, forward is positive, backward is negative; SumI is the speed adjustment integral value, Spd is the rotation speed, forward is positive, backward is negative, ki is the adjustment ratio; if Spd*SumI>0, SumI=0, the purpose is to prevent the integral of the speed from being in the same direction as the speed, generating a torque in the same direction as the movement.

[0035] After the first set time after the remote control module is turned off, the drive control module controls the motor to stop generating directional torque, and the motor switches to short-circuit the lower three transistors of the MOS of the drive control module ( Figure 2), after the motor actively short-circuits for a second set time, or after the motor actively short-circuits for a fourth set time and detects that the scooter / wheelchair is on flat ground for a third set time, the drive control module shuts down. In this embodiment, the first set time and the fourth set time are both 60S, the second set time is 40S, and the third set time is 80S.

[0036] This embodiment enables the drive control module to control the motor to output reverse torque, thereby preventing the scooter / wheelchair from rolling on a slope to achieve the braking function, so that there is no need to set an electromagnetic brake on the scooter / wheelchair. This has the advantages of reducing production and assembly processes, reducing the weight of the scooter / wheelchair to achieve lightweight. At the same time, the scooter / wheelchair does not need to keep the electromagnetic brake working all the time when in use, which can reduce energy consumption and extend the travel of the scooter / wheelchair.

Claims

1. A safety control method based on motor ramp shutdown, characterized in that The following steps are involved: S1. The motor receives a shutdown command; S2. After receiving the shutdown command, the drive control module detects whether the motor is on a ramp; compares the magnitude relationship between the motor current I and the minimum current I_limit when the motor is working. If I>I_limit, it means that the motor is on a ramp; S3. When it is determined that the motor is not on the ramp, the remote control module and the drive control module are directly shut down; When it is determined that the motor is on a slope, the slope shutdown process is executed; In the ramp shutdown process of step S3, after the drive control module receives the shutdown command, the remote control module shuts down, and the drive control module calculates the first brake torque output value PWM1 required for the motor to generate a reverse torque according to the angular velocity and moving distance of the wheel during rotation, and outputs PWM1 to the motor drive to enable the motor to generate the required reverse torque; When the remote control module is turned off for a first set time, the drive control module controls the motor to stop generating reverse torque, and the motor actively short-circuits; The calculation formula of PWM1 is as follows: PWM1=-Kp*Pos+SumI; SumI 后 =SumI 前 +(-Spd*ki); Among them, Kp is the moving distance adjustment parameter, Pos is the moving distance, which is positive when moving forward and negative when moving backward; SumI is the speed adjustment integral value, Spd is the rotation speed, which is positive when moving forward and negative when moving backward, and ki is the adjustment ratio; if Spd*SumI>0, SumI=0, it means that the moving direction and the braking direction are the same, then SumI is cleared and SumI is recalculated. 后 .

2. A safety control method based on motor ramp shutdown according to claim 1, characterized in that: In step S2, the magnitude relationship between the second braking torque output value PWM2 of the motor on the slope and Pwm_limit is compared, where Pwm_limit is the minimum braking torque output value of the motor when determining whether the motor is on the slope; When PWM2<-Pwm_limit, it is determined that the motor is on a downhill slope, and when PWM2>Pwm_limit, it is determined that the motor is on an uphill slope.

3. A safety control method based on motor ramp shutdown according to claim 2, characterized in that: In step S2, when the motor is a hub motor, the PWM2 of all motors is detected, and the size relationship between the PWM2 of all motors and Pwm_limit is compared. When the PWM2 of all motors is less than -Pwm_limit, it is judged that the motor is on a downhill slope. When the PWM2 of all motors is greater than Pwm_limit, it is judged that the motor is on an uphill slope.

4. A safety control method based on motor ramp shutdown according to claim 1, characterized in that: In step S3, if it is determined that the motor is on a slope, the drive control module sends a command to the remote control module, and the remote control module sends an alarm signal. After the shutdown button is pressed again, the remote control module shuts down.

5. The method for controlling the use of a motor based on ramp shutdown according to claim 1, characterized in that: In step S3, the motor is actively short-circuited by switching to short-circuit the lower three transistors of the MOS of the drive control module.

6. A safety control method based on motor ramp shutdown according to claim 1, characterized in that: In step S3, after the motor actively short-circuits for a second set time, or after it is detected that the motor is on flat ground for a third set time, and after the motor actively short-circuits for a fourth set time, the drive control module shuts down.

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