Motor driving circuit, motor driving system, electric power steering system, electric brake system, and vehicle driving system

• US 9,917,538 B2
• Filed: 07/12/2013
• Issued: 03/13/2018
• Est. Priority Date: 08/24/2012
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: Kanekawa, Nobuyasu, Kobayashi, Ryoichi, Koseki, Tomonobu, Yatsugi, Tomishige
• Primary Examiner(s): Dhakal, Bickey
• Application Number:
  US14/422,387
• Publication Number:
  US 20150214872A1
• Time in Patent Office: 1,705 Days
• Field of Search: 31840017
• CPC Class Codes: B60L 15/04 using dc
• CPC Class Codes: B60T 13/74 with electrical assistance or drive
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: B62D 5/0484 for reaction to failures, e.g. limp home
• CPC Class Codes: B62D 5/0487 detecting motor faults B62D5/0496 takes precedence
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes
• CPC Class Codes: H02M 1/0045 Converters combining the concepts of switch-mode regulation and linear regulation, e.g. linear pre-regulator to switching converter, linear and switching converter in parallel, same converter or same transistor operating either in linear or switching mode
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: H02P 29/032 Preventing damage to the motor, e.g. setting individual current limits for different drive conditions
• CPC Class Codes: H02P 6/085 in a bridge configuration
• CPC Class Codes: H02P 6/12 Monitoring commutation; Providing indication of commutation failure
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

In order to provide a motor driving circuit in which a portion corresponding to a failed phase can be separated while miniaturization and lower costs are achieved, a motor driving circuit for driving a motor includes: a second driver circuit for driving a driver circuit which supplies a drive current corresponding to one phase of a multiphase motor having three or more phases, to the multiphase motor; and an electrical circuit which includes a plurality of electrical components and switches a connecting relation between the electrical components according to an operation mode designated from outside the motor driving circuit, thereby providing a circuit function corresponding to the operation mode.

Claims

1. A motor driving circuit for driving a motor comprising:

a first driver circuit for driving a driver circuit which supplies a drive current corresponding to one phase of a multiphase motor having three or more phases, to the multiphase motor; and

electrical circuits which includes a plurality of electrical components and switches a connecting relation between the electrical components according to an operation mode designated from outside the motor driving circuit, the electrical circuits providing a circuit function corresponding to the operation mode, wherein the electrical circuits

includes an oscillation circuit which outputs an oscillation signal, a voltage-dividing resistor configured to switch a voltage division ratio, an arithmetic unit which compares a voltage divided by the voltage-dividing resistor with a predetermined reference voltage, a comparison circuit which compares a result of the comparison by the arithmetic unit with the output from the oscillation circuit, and a switching element which turns ON/OFF according to an output from the comparison circuit, and

switches whether to use the output from the oscillation circuit or not, according to the operation mode, and provides at least one of a switching regulator function and a linear regulator function as the circuit function corresponding to the operation mode, wherein

the motor driving circuit supplies a drive current corresponding to each phase of the multiphase motor, to the multiphase motor, and

at least one circuit functions provided by the electrical circuits provided in one of the motor driving circuits is configured to be different from a circuit function provided by the electrical circuits provided in another of the motor driving circuit.

2. The motor driving circuit according to claim 1, wherein the electrical circuits

switch the voltage division ratio according to the operation mode and provides different output voltages from each other as the circuit function corresponding to the operation mode.

3. The motor driving circuit according to claim 1, wherein the electrical circuits

include a capacitor charged with a voltage divided by the voltage-dividing resistor, a switch which turns ON/OFF a connection between the voltage-dividing resistor and the capacitor, a comparison circuit which compares the voltage divided by the voltage-dividing resistor with a predetermined reference voltage, and a switching element which turns ON/OFF and outputs a reset signal according to an output from the comparison circuit, and

switches the turning ON/OFF of the switch according to the operation mode and provides a plurality of types of reset circuit functions with different times for which the switching element continues to output the reset signal, as the circuit function corresponding to the operation mode.

4. The motor driving circuit according to claim 3, wherein the electrical circuits

switch the voltage division ratio according to the operation mode and provides a plurality of types of reset circuit functions with different detection threshold values that serve as a trigger for outputting the reset signal, as the circuit function corresponding to the operation mode.

5. The motor driving circuit according to claim 3, wherein the electrical circuits

include a watchdog timer which checks the presence or absence of a signal input in a predetermined cycle, an OR circuit which OR-connects an output of the comparison circuit and an output of the watchdog timer, and a switching element which turns ON/OFF according to an output from the OR circuit.

6. The motor driving circuit according to claim 1, wherein the electrical circuits

include a differential amplifier circuit and a hold circuit which holds an output from the differential amplifier circuit,

the hold circuit

includes a first switch which turns ON/OFF according to a sampling trigger signal, a second switch which turns ON/OFF according to a reset signal and is connected in parallel to the first switch, a capacitor charged with an output from the first switch or the second switch, and a third switch connected in parallel to the capacitor, and

switches the turning ON/OFF of each of the first switch, the second switch and the third switch according to the operation mode and provides one of a sample and hold function and a peak hold function as the circuit function corresponding to the operation mode.

7. The motor driving circuit according to claim 6, wherein the differential amplifier circuit

includes a loop circuit which feeds back an output from an amplifier circuit for amplifying a differential input, and a fourth switch which switches whether to cause the loop circuit to operate or not, according to the operation mode, and

the electrical circuits

switch the turning ON/OFF of the fourth switch according to the operation mode and causes a level shift function by the loop circuit to operate as the circuit function corresponding to the operation mode.

8. An electric power steering system comprising:

the motor driving system according to claim 1; and

a motor which is driven by the motor driving system and assists an operation of a steering device.

9. An electric brake system comprising:

the motor driving system according to claim 1; and

a motor which is driven by the motor driving system and actuates an electric brake.

10. A vehicle driving system comprising:

the motor driving system according to claim 1; and

a motor which is driven by the motor driving system and rotates wheels provided on a vehicle.