Motor drive control device

Patent metadata

Field	Value
Publication number	US-9428172-B2
Application number	US-201313887123-A
Country	US
Kind code	B2
Filing date	May 3, 2013
Priority date	May 28, 2012
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

An appropriate motor control in accordance with a pedal operation of a driver is to be achieved. A motor drive control device according to the present invention is a motor drive control device for an electric power-assisted vehicle that has one-way clutches respectively provided for a motor drive system and for a pedal drive system. The motor drive control device according to the present invention includes: a first calculating part that calculates a pedal rotation conversion speed that is converted from a pedal rotation; and a second calculating part that calculates a second target torque for a motor based on the pedal rotation conversion speed, during a period in which a first target torque derived from a pedal torque is not detected.

First claim

The invention claimed is:

1. A motor drive control device for an electric power-assisted vehicle provided with a motor drive system and a pedal drive system each of which is provided with a one-way clutch, the device comprising:
a first calculating part that calculates a pedal rotation conversion speed that is converted from a pedal rotation;
a second calculating part that, during a period in which a first target torque is not detected, calculates a second target torque for a motor based on the pedal rotation conversion speed, the first target torque being calculated based on a pedal torque;
a first processing part that generates a first value by converting a rotational speed of the motor to a duty cycle;
a second processing part that generates a second value by converting the second target torque to a duty cycle; and
a driver that controls switching of a switch provided in a complementary switching amplifier, based on an average duty cycle derived from a sum of the first value and the second value, the driver driving a motor that is connected to the complementary switching amplifier,
wherein the second calculating part calculates the second target torque in accordance with the first target torque during a period in which the first target torque is detected.

2. The motor drive control device according to claim 1 ,
wherein the second calculating part calculates the second target torque for the motor, based on a difference between speed of the motor and a target motor speed that is a smaller of the pedal rotation conversion speed and a vehicle speed.

3. The motor drive control device according to claim 2 ,
wherein, when a difference between the target motor speed and a rotational speed the motor, which is a value obtained by subtracting the rotational speed of the motor from the target motor speed, is a negative value or when a pedal is stopped, the second calculating part stops a drive of the motor.

4. The motor drive control device according to claim 2 ,
wherein, when an absolute value of a difference between the target motor speed and a rotational speed of the motor is smaller than a prescribed value, the second calculating part multiplies the difference between the target motor speed and the rotational speed of the motor by a gain that is smaller than that of when an absolute value of a difference between the target motor speed and the rotation speed of the motor is equal to or greater than the prescribed value.

5. The motor drive control device according to claim 2 ,
wherein, when an absolute value of a difference between the target motor speed and a rotational speed of the motor is smaller than a prescribed value, the second calculating part outputs, as the second target torque, a smaller of a first value and a predetermined second value, the first value being derived from the difference between the target motor speed and the rotational speed of the motor.

6. The motor drive control device according to claim 1 ,
wherein the second calculating part outputs the second target torque right after the first target torque is detected, the second target torque outputted by the second calculating part being gradually changed from a first value calculated based on the pedal rotation conversion speed to a second value calculated based on the pedal torque.

7. The motor drive control device according to claim 1 ,
wherein the electric power-assisted vehicle does not have a variable transmission, or drives wheels via a variable transmission that is shared by a pedal and the motor, and
wherein, when an absolute value of a difference between the pedal rotation conversion speed and a rotational speed of the motor is smaller than a prescribed value, the difference between the pedal rotation conversion speed and the rotational speed of the motor is multiplied by a gain that is smaller than that of when an absolute value of a difference between the pedal rotation conversion speed and a rotational speed of the motor is equal to or greater than the prescribed value.

8. The motor drive control device according to claim 1 ,
wherein the pedal rotation conversion speed is derived from a pedal rotation based on a fastest gear ratio.

9. The motor drive control device according to claim 1 , further comprising:
a coefficient calibrating part that conducts, during a period in which the first target torque is not detected, a process of calibrating a coefficient that is used when converting a rotational speed of the motor to a duty cycle by calculating the second target torque such that a motor speed becomes a prescribed speed at a prescribed timing.

10. A motor drive control device for an electric power-assisted vehicle provided with a motor drive system and a pedal drive system each of which is provided with a one-way clutch, the device comprising:
a first calculating part that calculates a pedal rotation conversion speed that is converted from a pedal rotation; and
a second calculating part that, during a period in which a first target torque is not detected, calculates a second target torque for a motor based on the pedal rotation conversion speed, the first target torque being calculated based on a pedal torque,
wherein the second calculating part calculates the second target torque in accordance with the first target torque during a period in which the first target torque is detected,
wherein the second calculating part outputs the second target torque right after the first target torque is detected, the second target torque outputted by the second calculating part being gradually changed from a first value calculated based on the pedal rotation conversion speed to a second value calculated based on the pedal torque, and
wherein the second calculating part increases the first value calculated based on the pedal rotation conversion speed to the second value calculated based on the pedal torque at a prescribed slew rate, when the first value is smaller than the second value.

11. A motor drive control device for an electric power-assisted vehicle provided with a motor drive system and a pedal drive system each of which is provided with a one-way clutch, the device comprising:
a first calculating part that calculates a pedal rotation conversion speed that is converted from a pedal rotation; and
a second calculating part that, during a period in which a first target torque is not detected, calculates a second target torque for a motor based on the pedal rotation conversion speed, the first target torque being calculated based on a pedal torque,
wherein the second calculating part calculates the second target torque for the motor, based on a difference between speed of the motor and a target motor speed that is a smaller of the pedal rotation conversion speed and a vehicle speed, and
wherein, when a difference between the target motor speed and a rotational speed of the motor, which is a value obtained by subtracting the rotational speed of the motor from the target motor speed, is a negative value, the second calculating part multiplies the difference between the target motor speed and the rotational speed of the motor by a gain that is less than 1 and that is smaller than that of when the difference between the target motor speed and the rotational speed of the motor is a positive value.

Assignees

• Microspace Corp
• Taiyo Yuden Kk

Inventors

• Tanaka Masato
• Asanuma Kazuo
• Hosaka Yasuo
• Kawagoe Kuniaki

Classifications

• B60L2200/12

  Bikes · CPC title

• B60L50/20

  using propulsion power generated by humans or animals · CPC title

• B60L2240/12

  Speed · CPC title

• B60L2250/24

  by lever actuation · CPC title

• B60L2240/423

  Torque · CPC title