Methods and systems of sensing back-electromotive force in electric motors

    公开(公告)号:US11888431B2

    公开(公告)日:2024-01-30

    申请号:US17815790

    申请日:2022-07-28

    Inventor: Ezio Galbiati

    CPC classification number: H02P6/182 H02P6/08

    Abstract: A method includes driving a selected motor winding to be in a tri-state during a time interval having a finite time length value of a time window, sensing a zero-crossing (ZC) of an oscillating back electromotive force induced in the motor winding during the time window in which the motor winding is in the tri-state, and producing a ZC sensing signal, which has a first edge at a first time instant at the sensed ZC and a second edge at a second time instant separated from the first time instant by a half oscillation of the oscillating back electromotive force, detecting a phase of a current flowing in the motor winding at a time instant time-shifted with respect to the second time instant of the second edge of the ZC sensing signal, and adjusting the finite time length value based on the detected phase of the current.

    METHOD OF DRIVING AN ELECTRICAL LOAD AND CORRESPONDING DRIVER CIRCUIT

    公开(公告)号:US20230074792A1

    公开(公告)日:2023-03-09

    申请号:US17819504

    申请日:2022-08-12

    Abstract: A method of driving an electrical load includes coupling a power supply source to a power supply pin of a driver circuit, and coupling an electrical load to at least one output pin of the driver circuit. A driver sub-circuit of the driver circuit produces at least one driving signal for driving the electrical load. The at least one driving signal is provided to the electrical load via the at least one output pin. The at least one driving signal is modulated to supply the electrical load with a load current and to subsequently interrupt the load current. A compensation current pulse is sunk from the power supply pin, at a compensation circuit of the driver circuit, in response to the load current being interrupted.

    METHODS AND SYSTEMS OF SENSING BACK-ELECTROMOTIVE FORCE IN ELECTRIC MOTORS

    公开(公告)号:US20230061437A1

    公开(公告)日:2023-03-02

    申请号:US17815790

    申请日:2022-07-28

    Inventor: Ezio Galbiati

    Abstract: A method includes driving a selected motor winding to be in a tri-state during a time interval having a finite time length value of a time window, sensing a zero-crossing (ZC) of an oscillating back electromotive force induced in the motor winding during the time window in which the motor winding is in the tri-state, and producing a ZC sensing signal, which has a first edge at a first time instant at the sensed ZC and a second edge at a second time instant separated from the first time instant by a half oscillation of the oscillating back electromotive force, detecting a phase of a current flowing in the motor winding at a time instant time-shifted with respect to the second time instant of the second edge of the ZC sensing signal, and adjusting the finite time length value based on the detected phase of the current.

    Method of PWM regulation of a continuous current electric motor
    14.
    发明授权
    Method of PWM regulation of a continuous current electric motor 有权
    连续电动机PWM调节方法

    公开(公告)号:US09294030B2

    公开(公告)日:2016-03-22

    申请号:US14168171

    申请日:2014-01-30

    CPC classification number: H02P23/0031 H02P6/14 H02P23/0004

    Abstract: A method of PWM regulating a motor through a half-bridge drive stage includes sampling the motor current to obtain sampled values during driving intervals or during current decay intervals, and comparing a last sampled value with a current threshold. The motor is coupled in a slow decay electrical path for the duration of a current decay interval if the last sampled value does not exceed the current threshold. Otherwise the motor is coupled in a fast decay electrical path for a portion of the duration of the current decay interval, and is coupled in the slow decay electrical path for a remaining part of the duration of the same current decay interval.

    Abstract translation: 通过半桥驱动级PWM调节电动机的方法包括:在驱动间隔期间或电流衰减间隔期间对电动机电流进行采样以获得采样值,并将最后采样值与电流阈值进行比较。 如果最后一个采样值不超过当前阈值,则电机在电流衰减间隔的持续时间内以慢衰减电路连接。 否则,电动机在电流衰减区间的持续时间的一部分中以快速衰减电路连接,并且在慢衰减电路中被耦合在相同电流衰减间隔的持续时间的剩余部分中。

    Method and related driver of a permanent magnet synchronous electric motor
    15.
    发明授权
    Method and related driver of a permanent magnet synchronous electric motor 有权
    永磁同步电动机的方法及相关驱动器

    公开(公告)号:US09257920B2

    公开(公告)日:2016-02-09

    申请号:US14327048

    申请日:2014-07-09

    CPC classification number: H02P6/002 H02P6/085 H02P6/182 H02P6/28 H02P6/34

    Abstract: A method of driving a permanent magnet synchronous electric motor includes sensing or estimating a back electromotive force induced in at least a winding of the motor by the rotation of a rotor of the motor; and reading, from a memory, values of a first voltage waveform having a phase angle with respect to the back electromotive force. The method also includes generating a driving voltage corresponding to the sum of values of a control voltage, obtained as product of the values of the first voltage waveform by a first coefficient determined as a function of a desired value of motor torque, and values of a cancelation voltage of the back electromotive force. The method also includes applying the driving voltage at the motor winding.

    Abstract translation: 驱动永久磁铁同步电动机的方法包括通过电动机的转子的旋转感测或估计在电动机的至少一个绕组中感应的反电动势; 以及从存储器读取具有相对于所述反电动势的相位角的第一电压波形的值。 该方法还包括产生与作为第一电压波形的值的乘积的控制电压的值的和相对应的驱动电压,该第一系数作为电动机转矩的期望值确定的第一系数,以及 背电动势的取消电压。 该方法还包括在电动机绕组处施加驱动电压。

    Current sensing circuit and hard disk drive including same

    公开(公告)号:US12033663B2

    公开(公告)日:2024-07-09

    申请号:US18343868

    申请日:2023-06-29

    Inventor: Ezio Galbiati

    CPC classification number: G11B21/025 G11B25/043 G11B27/36 G11B2220/2516

    Abstract: A circuit includes a set of input nodes configured to be coupled to respective ones of the windings of a spindle motor in a hard disk drive to sense the voltages applied to the windings. A set of output nodes is configured to provide output signals indicative of direction of flow of the currents through the windings. Level shifters are coupled to respective input nodes in the set of input nodes and have level-shifted output nodes configured to provide down-shifted replicas of the voltages at the respective input nodes in the set of input nodes. Flip-flops have inputs coupled to respective ones of the level-shifted output nodes of the level shifters and outputs configured to provide the output signals coupled to respective output nodes.

    METHOD OF OPERATING HARD DISK DRIVES AND CORRESPONDING CONTROL CIRCUIT

    公开(公告)号:US20240038263A1

    公开(公告)日:2024-02-01

    申请号:US18354797

    申请日:2023-07-19

    CPC classification number: G11B5/54 H02P7/025

    Abstract: An embodiment method includes rectifying a back electromotive force of a spindle motor in a hard disk drive and energizing a voice coil motor in the hard disk drive using the rectified back electromotive force of the spindle motor via a voice coil motor power stage to retract a head of the hard disk drive to a park position. The head is retracted by moving the head towards the park position during a first retract phase and retaining the head in the park position during a second retract phase by applying a bias voltage to the voice coil motor power stage during a bias interval of the second retract phase. The method also includes producing a saturation signal indicative of onset of saturation in the voice coil motor power stage and controlling the bias voltage during the second retract phase.

    Method of driving an electrical load and corresponding driver circuit

    公开(公告)号:US11855554B2

    公开(公告)日:2023-12-26

    申请号:US17819504

    申请日:2022-08-12

    CPC classification number: H02M7/537 H02M1/32 H02P6/16

    Abstract: A method of driving an electrical load includes coupling a power supply source to a power supply pin of a driver circuit, and coupling an electrical load to at least one output pin of the driver circuit. A driver sub-circuit of the driver circuit produces at least one driving signal for driving the electrical load. The at least one driving signal is provided to the electrical load via the at least one output pin. The at least one driving signal is modulated to supply the electrical load with a load current and to subsequently interrupt the load current. A compensation current pulse is sunk from the power supply pin, at a compensation circuit of the driver circuit, in response to the load current being interrupted.

    METHOD OF OPERATING AN ELECTRIC MOTOR, CORRESPONDING DEVICE AND HARD DISK DRIVE

    公开(公告)号:US20230352050A1

    公开(公告)日:2023-11-02

    申请号:US18300806

    申请日:2023-04-14

    CPC classification number: G11B19/2072

    Abstract: A method includes coupling an electric motor in a hard disk drive to a set of driver circuits. Each driver circuit includes a high-side switch and a low-side switch. The high-side switch has a high-side current flow path between a supply node coupled to a supply voltage and a switching node coupled to a winding of the electric motor. The low-side switch has a low-side current flow path between the switching node and ground. Respective conduction currents are generated through the low-side current flow paths, in response to a command to reduce the motor speed by coupling a drive voltage to the control terminals of the low-side switches. An intensity of at least one of the respective conduction currents is sensed. In response to the sensed current intensity exceeding a current intensity threshold, the control terminals of the low-side switches are coupled to respective ones of the switching nodes.

    Method of controlling a half-bridge circuit

    公开(公告)号:US11652479B2

    公开(公告)日:2023-05-16

    申请号:US17659226

    申请日:2022-04-14

    CPC classification number: H03K17/6877 H02M1/0025 H02M3/157 H03K17/6874

    Abstract: A method of controlling a half-bridge circuit includes receiving an analog feedback signal proportional to an output of the half-bridge circuit, comparing the received analog feedback signal with a threshold value, selecting a digital feedback signal based on a result of the comparing, comparing the digital feedback signal with a digital reference signal to generate a digital error signal, integrating the digital error signal to generate an integration error signal, downscaling the integral error signal to generate a downscaled integration signal, sampling the downscaled integration signal to generate a sampled integration signal, and generating pulsed signals from the sampled integration signal to provide an input to the half-bridge circuit.

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