Minebea Mitsumi Inc.

Minebea Company, Limited

Hidetoshi Hijikata

Kazuo Takada

Takayuki Matsui

Toshihiro Tamitsuji

Takamichi Kitano

Haruka Miyaji

Shigeki Miyaji

Ayaka Shimada

Scott Jacobs

Yuuya Hisatomi

A motor drive control device capable of determining a drive state of a motor is provided. The motor drive control device includes a plurality of motor drive circuits performing, based on drive control signals (Scaand Sca) for controlling the number of rotations of a motor, control of energization of the motor and outputting FG signals (fgand fg) having a cycle corresponding to the actual number of rotations of the motor, a composite signal generation circuit receiving an input of each of the FG signals output from the motor drive circuits and generating a composite signal by combining input signals, and a drive control circuit generating, based on a speed command signal indicating a target number of rotations of the motor, the drive control signals and outputting the drive control signals to each of the motor drive circuits. The FG signals output from the motor drive circuits have a phase difference from each other.

Motor drive control device, fan, and motor drive control method

The present application makes it possible to measure a PWM signal in a wide frequency range. A PWM signal measurement device () includes: a first duty cycle measurement unit () of a capture type configured to measure a frequency (f) and a duty cycle of a PWM signal (Sc); a voltage measurement unit () configured to measure a smoothed voltage (Vad) obtained by smoothing the PWM signal using a smoothing circuit (); a second duty cycle measurement unit () of a smoothing type configured to measure a duty cycle of the PWM signal on the basis of a measured voltage value (Vadm) of the smoothed voltage; and a measurement-type selecting unit () configured to select one of the capture type or the smoothing type on the basis of a measured value of the frequency and a measured value of the smoothed voltage.

PWM signal measurement device, motor drive control device, PWM signal measurement method, and motor drive control method

A rotational stop position of a motor is accurately controlled. A motor driving control device () includes a BEMF detection unit () for detecting zero-cross of back electromotive force of a motor coil provided in a motor, and a CPU () for controlling driving of the motor by a 1-phase energization method and, without a position sensor, performing commutation based on the zero-cross of the back electromotive force detected by the BEMF detection unit (), controlling driving of the motor based on a rotational speed corresponding to a drive voltage and a load, and performing extension control of a commutation time for each step from a calculated deceleration start step until the rotational speed of the motor decreases to a predetermined rotational speed or less for enabling the motor to stop at a desired stop position when the driving of the motor is stopped.

Motor driving control device and motor driving control method

A motor control circuit includes an input voltage measuring unit, a temperature measuring unit, a current setting unit, and a current control unit. The input voltage measuring unit measures an input voltage input to the motor control device. The temperature measuring unit measures the temperature. The current setting unit sets a target value of drive current to flow through a coil of a stepping motor based on a measurement result of the input voltage measuring unit and a measurement result of the temperature measuring unit and based on a set value of drive current preset for each of plural partial areas, which are sectioned in a matrix form with a threshold value related to the input voltage and a threshold value related to the temperature. The current control unit controls the drive current according to the target value of the drive current set in the current setting unit.

Motor control circuit, motor control device, actuator and control method for stepping motor

In order to prevent erroneous detection of motor step-out even when the rotational speed of the motor crosses a resonance region of the motor under acceleration and/or deceleration, a motor control device () includes a control unit for performing control so as to apply a pulse voltage modulated in pulse width to each of coils of plural phases equipped in a motor () and periodically switch the phases of the coil currents flowing through the coils of the plural phases, a back electromotive force measuring unit () for providing a stop period for temporarily stopping application of the pulse voltage to a coil of any one phase out of the coils of the plural phases when the direction of a coil current flowing through the coil of the phase switches, and measuring back electromotive force induced in the coil during the stop period, and a step-out state detecting unit for detecting a step-out state when the rotational speed of the motor () is not in a resonance region of the motor () and the back electromotive force measured by the back electromotive force measuring unit () satisfies a predetermined step-out state determination criterion.

Motor control device and step-out state detection method

This motor control device has an inexpensive configuration and enhances motor current target value tracking. This motor control device has an H bridge circuit that has a switching element and is connected to a motor coil provided in a motor, and a control means that drives the switching element at each prescribed PWM period and specifies an operation mode for the H bridge circuit from among a charge mode for increasing the motor current (Icoil) flowing through the motor coil, a fast decay mode for decreasing the motor current, and a slow decay mode. In each PWM period, the control means selects one of the operation modes on the basis of the result of comparing the motor current and a current reference value (Iref) before the time that has passed from the start of the PWM period reaches a prescribed current control re-execution time (Tr) and selects one of the operation modes on the basis of the result of comparing the motor current and the current reference value after the time that has passed reaches the current control re-execution time.

Motor control device and motor controlling method

A motor control circuit () capable of performing a high-precision step-out determination under a wide range of conditions. The motor control circuit () includes an input voltage measuring unit (), a temperature measuring unit (), a back electromotive force measuring unit (), a determination threshold value setting unit, and a determination unit. The input voltage measuring unit () measures an input voltage input to a motor control device (). The temperature measuring unit () measures temperature. The back electromotive force measuring unit () measures back electromotive force induced in a coil for which energization is stopped out of the coils of plural phases. The determination threshold value setting unit sets a determination threshold value of back electromotive force based on a measurement result of the input voltage measuring unit () and a measurement result of the temperature measuring unit (), and based on a determination reference value that is preset for each of plural partial areas sectioned in a matrix form with a threshold value relating to the input voltage and a threshold value relating to the temperature. The determination unit makes a determination on step-out of a stepping motor () based on a measurement result of the back electromotive force measuring unit () and the set determination threshold value of the back electromotive force.

A motor drive controlling apparatus includes: a controller that generates and outputs a drive control signal, in response to input of a speed command signal and a rotational direction signal; a motor driver that generates and outputs a drive signal to a motor, in response to the drive control signal; and an encoder that detects a rotational position of the motor to output an encoder signal. The controller includes: a measurement unit that detects, based on the encoder signal, a time at which a rotational state of the motor becomes, caused by an external factor, different from that commanded by the speed command and rotational direction signals, and measures a movement amount from the time; and a transmitting unit that transmits, to the motor driver, a signal for stopping an output of the drive signal, when the movement amount and a drive-control-signal outputting state satisfy a predetermined condition.

Motor drive controlling apparatus, motor drive controlling method, and tube pump

A motor drive controlling apparatus includes: a controller that outputs a drive control signal; a motor driver that generates and outputs a drive signal to a motor; and an encoder that detects a rotational position of the motor. The controller has a measurement unit that detects a time point when rotation of the motor is switched to a reverse direction of a target rotational direction by an external factor during input of the speed command signal, and measures a movement amount in the reverse direction from a rotational position of the motor at a time point of the switching, and a transmitting unit that transmits, to the motor driver, a switching signal that switches a conduction method from 180-degree conduction to 120-degree conduction in a case where the movement amount is a predetermined threshold or more.

The wireless power transmission system includes a power supply device and a power receiving device. The power supply device includes a power supply coil, an inverter driving the power supply coil and a radio and a first processor. The power receiving device includes a resonant circuit wirelessly receiving electric power from the power supply coil, a rectifying circuit DB outputting a rectified voltage, a load, a radio unit and a second processor. The second processor transmits a communication packet in a predetermined period of time, the communication packet including information about a rectified voltage value and a circulation index value indicating transmission sequence. The first processor outputs a signal according to the rectified voltage value included in the communication packet every time the first processor receives the communication packet without delay.

Wireless power transmission system, and communication and protection methods for the same

A controller of a motor controller operates to perform a process including: controlling the H bridge circuit to switch to the charge mode; controlling the H bridge circuit to switch to the high-dissipation mode when the zero-cross detector detects that the back electromotive force voltage of the motor coil connected to a phase of the H bridge circuit shortly before the H bridge circuit is zero-crossed; controlling the H bridge circuit to switch to the low-dissipation mode after a predetermined time has elapsed; and controlling the H bridge circuit to switch to the free mode when the motor current detector detects that the motor current flowing in the motor coil connected to the H bridge circuit flows in a direction opposite to that in the charge mode.

Motor controller and method for controlling motor

A motor current controller operates to: set a reference current value and a decay mode switching time for each PWM cycle based on a positional relationship between a rotor and a stator; switch an H-bridge circuit to the charge mode at the time of start of each PWM cycle; switch the H-bridge circuit to the fast decay mode and store a charge mode time when determined that the motor current is greater than the reference current value; switch the H-bridge circuit to the slow decay mode when the decay mode switching time elapses; compare the charge mode time of the corresponding PWM cycle in a present falling side with the charge mode time of the PWM cycle in a previous falling side; update the decay mode switching time of the PWM cycle previous to the corresponding PWM cycle in a subsequent falling side.

Motor current controller and method for controlling motor current

A controller of a motor controller operates to perform a process including: controlling the H bridge circuit to switch to the charge mode; controlling the H bridge circuit to switch to the high-dissipation mode when the zero-cross detector detects that the back electromotive force voltage of the motor coil connected to a phase of the H bridge circuit shortly before the H bridge circuit is zero-crossed; controlling the H bridge circuit to switch to the low-dissipation mode after a predetermined time has elapsed; and controlling the H bridge circuit to switch to the free mode when the voltage detector detects that the differential voltage between the motor coils connected to the H bridge circuit is lower than a predetermined voltage.

A motor current controller includes: an H-bridge circuit that includes a switching element and is connected to a motor coil provided in a motor; and a control unit that drives the switching element every PWM cycle and designates an operation mode from among a plurality of modes including a charge mode, in which a motor current flowing in the motor coil increases, and a decay mode, in which the motor current is decreased for the H-bridge circuit. The control unit operates to select the decay mode as the operation mode with higher priority during a period in which the PWM cycle ends after the maximum duty time elapses from the start of each PWM cycle.

There is provided a motor control device controlling an energizing state of a coil of each phase for driving a stepping motor having multiple phase coils. The motor control device includes a detecting unit configured to detect whether the stepping motor is out of step, and a reverse rotating unit configured, when the detecting unit detects that the stepping motor is out of step, to rotate the stepping motor in a second rotation direction reverse to a first rotation direction, which is a rotation direction of the stepping motor before detecting out-of-step, by a number of steps with which a stress received by the stepping motor is alleviated, before the stepping motor spontaneously rotates in the second direction.

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Hamamatsu, Japan

Hidetoshi Hijikata