Motor drive controller and method for detecting rotation state
AssigneeMinebea Co., Ltd.
InventorsHiroyuki Kaidu, Masato Aoki
Life of this patent
Estimating the term…
Abstract
A motor drive controller is for controlling a motor having multiple phases and includes: a comparison reference voltage generator that generates a predetermined constant voltage as a comparison reference voltage; a counter-electromotive voltage comparator that compares the comparison reference voltage with a counter-electromotive voltage of each phase of the motor; and a rotation state detector that detects a rotation state of the motor based on positive/negative polarities of counter-electromotive voltages of other phases with respect to the comparison reference voltage at the time of an occurrence of a zero cross between the counter-electromotive voltage of any one phase and the comparison reference voltage.
Claims6
A motor drive controller for controlling a motor having multiple phases, the motor drive controller comprising:
- a comparison reference voltage generator that generates a predetermined constant voltage as a comparison reference voltage;
- a counter-electromotive voltage comparator that compares the comparison reference voltage with a counter-electromotive voltage of each phase of the motor;
- and
- a rotation state detector that detects a rotation state of the motor based on positive/negative polarities of counter-electromotive voltages of other phases with respect to the comparison reference voltage at the time of an occurrence of a zero cross between the counter-electromotive voltage of any one phase and the comparison reference voltage,
- wherein the number of the phase of the motor is three, and
- wherein the rotation state detector detects that the motor is in forward rotation at a predetermined speed or higher in a case where, when a zero cross between the rise of the counter-electromotive voltage of any one phase and the comparison reference voltage occurs, the counter-electromotive voltage of another phase leading the phase is positive with respect to the comparison reference voltage, and the counter-electromotive voltage of another phase retarding the phase is negative with respect to the comparison reference voltage.
A method for detecting rotation state of a three-phase motor, the method comprising:
- generating a predetermined constant voltage as a comparison reference voltage;
- comparing the comparison reference voltage with a counter-electromotive voltage of each phase of the motor;
- detecting a rotation state of the motor based on positive/negative polarities of the counter-electromotive voltages of the other phases with respect to the comparison reference voltage at the time of an occurrence of a zero cross between the counter-electromotive voltage of any one phase and the comparison reference voltage;
- and
- detecting that the motor is in forward rotation at a predetermined speed or higher in a case where, when a zero cross between the rise of the counter-electromotive voltage of any one phase and the comparison reference voltage occurs, the counter-electromotive voltage of another phase leading the phase is positive with respect to the comparison reference voltage, and the counter-electromotive voltage of another phase retarding the phase is negative with respect to the comparison reference voltage.
A method for detecting rotation state of a three-phase motor, the method comprising:
- generating a predetermined constant voltage as a comparison reference voltage;
- comparing the comparison reference voltage with a counter-electromotive voltage of each phase of the motor;
- detecting a rotation state of the motor based on positive/negative polarities of the counter-electromotive voltages of the other phases with respect to the comparison reference voltage at the time of an occurrence of a zero cross between the counter-electromotive voltage of any one phase and the comparison reference voltage;
- and
- detecting that a rotation speed of the motor is less than a predetermined speed in a case where, when a zero cross between the rise of the counter-electromotive voltage of any one phase and the comparison reference voltage occurs, both the counter-electromotive voltage of another phase leading the phase and the counter-electromotive voltage of another phase retarding the phase have a same sign with respect to the comparison reference voltage.
A motor drive controller for controlling a motor having multiple phases, the motor drive controller comprising:
- a comparison reference voltage generator that generates a predetermined constant voltage as a comparison reference voltage;
- a counter-electromotive voltage comparator that compares the comparison reference voltage with a counter-electromotive voltage of each phase of the motor;
- and
- a rotation state detector that detects a rotation state of the motor based on positive/negative polarities of counter-electromotive voltages of other phases with respect to the comparison reference voltage at the time of an occurrence of a zero cross between the counter-electromotive voltage of any one phase and the comparison reference voltage,
- wherein the number of the phase of the motor is three, and
- wherein the rotation state detector detects that a rotation speed of the motor is less than a predetermined speed in a case where, when a zero cross between the rise of the counter-electromotive voltage of any one phase and the comparison reference voltage occurs, both the counter-electromotive voltage of another phase leading the phase and the counter-electromotive voltage of another phase retarding the phase have a same sign with respect to the comparison reference voltage.
Dependencies are inferred from the claim text.