Abstract: When a forced commutation mode ends, a switchover to a sensorless control mode is made. The sensorless control mode immediately after the switchover to the sensorless control mode is executed with a power source current maximum value set at a value higher than a rated current value of a motor. The sensorless control mode immediately after the switchover is executed only over a predetermined period of time, and, after a lapse of the predetermined period of time, a steady sensorless control mode is executed. In the steady sensorless control mode, the power source current maximum value is set at a value equal to the rated current value of the motor.

Abstract: An inverter control device controls the operation of a brushless DC motor selsorlessly. A driving controller of the inverter control device switches commutation of switching elements from control based on a position detection commutation signal to control based on a forced synchronization commutation signal if an output voltage of an inverter circuit section is equal to or greater than a preset threshold and a value of a rotational speed detected by the rotational speed detector is equal to or less than a reference value less than a target value of the rotational speed. The output voltage controller of the inverter control device changes the output voltage control signal based on a phase difference detected by a phase difference detector when the driving controller is controlling commutation of switching elements based on the forced synchronization commutation signal.

Abstract: A command rotation speed is set to an initial rotation speed, and a forced commutation mode is started. In the forced commutation mode, a rotation speed is increased by a predetermined increase amount each time and forced commutation is executed until the rotation speed reaches a set rotation speed. Then, a switchover to the sensorless control mode is made when the rotation speed reaches the set rotation speed (S4) and a rotor position becomes detectable.

Abstract: A method of operating a brushless direct current motor is provided that generates a rotor position dependent pulse width modulation waveform. The waveform can improve motor efficiency and reduce torque variation.

Abstract: A motor control apparatus has an inverter circuit, which includes FETs for converting electric power supplied to a motor. A capacitor is provided between a battery and the inverter circuit. A pull-up resistor connects a V-phase of the motor to a high potential side of the battery. A power supply relay permits or interrupts current flow from the battery to the capacitor and the motor. A microcomputer controls the power supply relay and the motor. The microcomputer turns on a low-side FET of a V-phase under a condition that the power supply relay is interrupting the current flow before the motor is started. Electric charge stored in the capacitor is discharged to a low potential side of the battery through the pull-up resistor.

Abstract: A conventional method used for a startup mode for a brushless direct current (DC) motor employed complementary inductive rise times. Specifically, inductive rise times rise times for a driving state and its complementary state were compared to one another such that when the inductive rise times cross a switching point had been reached. This methodology, however, significantly affects the efficiency of the driving torque and power consumption. Here, however, a derivative of the inductive rise time is employed, which can determine the switching event without the need for a use of a complementary state, improving motor performance.

Abstract: A system includes a control module that controls a motor based on a first rotor angle and an angle determination module that generates the first rotor angle. An estimator module determines an estimated rotor angle of the motor. A transition module generates a transition signal in response to convergence of the estimator module. The angle determination module initially generates the first rotor angle based on an open loop angle. In response to the transition signal, the angle determination module switches to generating the first rotor angle based on the estimated rotor angle and an offset value. The offset value is based on a difference between the estimated rotor angle and the open loop angle at the time when the transition signal is generated.

Abstract: An example method of initiating operation of a wound field synchronous machine in a motoring mode includes estimating an initial position of a rotor of a wound field synchronous machine using a carrier injection sensorless stimulation signal. The method tracks an operating position of the rotor based on current harmonics of the wound field synchronous machine. The method also calibrates the tracking using the initial position.

Abstract: Methods and systems for controlling an electric motor are provided. The motor includes a plurality of windings. Each winding is coupled to a respective set of first and second switches. The first switch of each set of switches is simultaneously activated. Current flow through the plurality of windings is measured while the first switch of each set of switches is activated. The electric motor is controlled according to a first motor control method if the measured current is below a predetermined threshold. The electric motor is controlled according to a second motor control method if the measured current is above the predetermined threshold.

Abstract: In order to determine a drive force (FAct) produced by an electric motor, the motor current (Ia) supplied to the electric motor (10) from a power supply source (32) is measured and a force is calculated from this; in addition, the motor voltage (UBat) applied to the electric motor (10) is measured, and drive force fluctuations which result from voltage fluctuations that occur during operation of the power supply source are compensated for, with at least one compensation force component being determined which is based on the measured motor voltage (UBat), including voltage fluctuations.

Abstract: The present invention discloses a start-up circuit for a motor driving IC. The activation circuit includes a determination unit, for generating a determination result indicating an operating mode of the motor driving IC according to an external pulse width modulation signal, and an output unit, for outputting an activation signal according to the determination result and a pulse width modulation activation signal. A duty of the pulse width modulation activation signal is greater than a duty of the external pulse width modulation signal.

Abstract: A method of controlling an electrical machine. The electrical machine includes a stator having a core and a plurality of windings, and a rotor disposed adjacent to the stator to interact with the stator. The method includes detecting a movement of the rotor, generating a three phase alternating current (AC) voltage signal by all phases of the electrical machine, monitoring for a transfer speed of the electrical machine, discontinuing the three phase AC voltage signal when the transfer speed is traversed, and switching to a back electromotive force (BEMF) control mode after discontinuing the three phase AC voltage signal.

Abstract: A sensorless starting control method for a brushless direct current (BLDC) motor, comprising a first rotor-positioning step configured to position a rotor in a first position by operating a coil unit in a first excitation state, a second rotor-positioning step configured to operate the coil unit in a second excitation state such that the rotor rotates from the first position to a second position, and an open-looped starting step configured to excite a plurality of coils of the coil unit in sequence so as to drive the rotor to rotate in a predetermined direction, wherein the coil unit generates a back electromotive force (EMF) when the rotor rotates in the predetermined direction. The method further comprises a close-looped operation step configured to control the BLDC motor to attain a predetermined rotational speed via a feedback of the back EMF.

Abstract: An electronically commutated one-phase motor (20; 20?) has a stator having at least one winding strand (30, 32; 30?), and it has a permanent-magnet rotor (22) that induces, as it rotates, a voltage (uind) in the winding strand. The motor further has an electronic calculation device or microcontroller (26) which is configured to execute, during operation, the following steps repetitively: sampling the induced voltage (uind) in a currentless winding strand, for example, during a half-wave of the induced voltage, in order to obtain a plurality of analog voltage values; digitizing the analog voltage values in order to obtain a plurality of digitized voltage values; and processing the plurality of digitized voltage values to ascertain the instantaneous rotation direction of the motor rotor. The control circuit then can use these data to assure reliable motor start-up, regardless of any external driving forces which occur.

Abstract: An apparatus for controlling a wheel motor is provided. A plurality of switches is provided for controlling a direction of current through motor coils of the wheel motor. A brushless motor control circuit is connected to each of the plurality of switches. Responsive to a request to adjust one of an angular velocity and an angular acceleration of the wheel motor, the plurality of switches are activated to place the motor coils in a predetermined configuration to maximize torque or reduce a total back electromotive force (BEMF) from the motor coils.

Abstract: A drive apparatus includes a magnet rotor having a plurality of magnetic poles that are magnetized, a stator having a magnetic pole portion that opposes each pole of the magnet rotor, a coil configured to excite the magnetic pole portion, a position detector configured to detect a position of the magnet rotor, a first driver configured to switch an electrification state of the coil in accordance with a preset time interval, a second driver configured to switch an electrification state of the coil in accordance with an output of the position detector, and a controller configured to select the first driver when the output of the position detector is less than a first threshold, and to select the second driver when the output of the position detector is equal to or larger than the first threshold.

Abstract: In a method for operating an electric machine of a drive device, which electric machine has a rotor and a stator, and which drive device has a drive unit, an angular position of the rotor with respect to the stator is determined on the basis of an angle-of-rotation encoder associated with the drive unit.

Abstract: A motor starting apparatus includes a driving signal generating unit that generates an open-loop driving signal and a drive circuit that is connected to a motor. The driving signal generating unit includes a data storing unit that stores therein predetermined data, a velocity integrating unit that integrates velocity data, a phase adjusting signal generating unit that generates a phase adjusting signal, a three-phase driving signal generating unit that generates a three-phase applied voltage, and a drive circuit driving unit that generates a driving signal of the motor. The three-phase driving signal generating unit performs open-loop driving by outputting the three-phase applied voltage based on the phase adjusting signal to the drive circuit driving unit.

Abstract: A drive system of a permanent magnet motor is constituted of a mode switching trigger generator which monitors a state of a permanent magnet motor and issues a mode switching trigger, a conduction mode determining unit which receives the mode switching trigger and switches the mode of the permanent magnet motor, and a PWM generator which outputs a PWM signal to an inverter in accordance with the output of the conduction mode determining unit. The mode switching trigger is generated on condition that the speed electromotive force of the permanent magnet motor exceeds a constant or variable threshold value.

Abstract: A method and device for controlling an electric motor, in particular a machine tool drive, wherein during a sensorless open-loop control mode of operation of the electric motor the speed and the torque are determined from the motor current and the motor voltage, and the moment of inertia of the electric motor torque are determined from the determined motor current and the determined motor voltage, wherefrom then a control torque is determined, which is then associated with an open-loop torque control value and supplied as the torque setpoint value to a control element for setting the motor current and/or the motor voltage in the open-loop mode of operation. As long as the speed is below a minimum speed, the control element receives as input variable a control or pilot control torque generated from a predefined moment of inertia for a sensorless closed-loop control mode of operation of the electric motor.

Abstract: A motor driving circuit includes an inverter circuit which supplies a driving current to a coil of a single phase brushless DC motor, a position detection sensor which detects a magnetic pole position of a magnet rotor of the motor and outputs a position detection signal, and a controller which controls the inverter circuit based on the position detection signal and a speed instruction signal for instructing a rotating speed of the motor. At a time of startup of the motor, the controller makes a pulse width of a PWM signal for controlling the inverter circuit constant in a first time period which starts after the position detection signal zero-crosses and lasts until the position detection signal zero-crosses next time, and narrows the pulse width of the PWM signal as time elapses in a second time period immediately after the first time period.

Abstract: Embodiments of the present invention provide a device and method for generating initial operating points for controlling an interior permanent magnet (IPM) machine. The method includes loading an inductance lookup table, first calculating a maximum torque per Ampere (MTPA) trajectory for a first threshold speed based on machine parameters of the IPM machine, second calculating a truncated voltage limit ellipse with monotonically increasing torque for a first speed based on the machine parameters, if the first speed is higher than the first threshold speed, determining an operating trajectory at the first speed based on at least one of the calculated MTPA trajectory and the calculated truncated voltage limit ellipse, and generating an Id,Iq map that maps an Id value and an Iq value to each torque command of a plurality of torque commands for the first speed based on the determined operating trajectory.

Abstract: A method for operating an electric motor with at least two motor terminals that are driven by a control device contains the steps of short-circuiting of at least two of the motor terminals of the electric motor by the control device; measurement of the motor phase currents at the short-circuited motor terminals; and identification of a standstill of the electric motor if a magnitude and/or a frequency of the motor phase currents measured lies below a predefined limit value. In the case of such a reliable identification of the standstill of the electric motor, an enable signal can then advantageously be generated in order, by way of example, to enable access to an apparatus driven by the electric motor.

Abstract: To further improve the stability of drive control for the start period of a motor without complicating a circuit configuration. During the period in which the rotational speed of a rotor does not reach the rotational speed capable of locking a PLL circuit, a drive control method of two-phase mode in which a start current is supplied by two energizing patterns is used. In energizing pattern A, a current is caused to flow in a motor winding in the direction from U to W and in the direction from V to W at the same time. In energizing pattern B, a current is caused to flow in the motor winding in the direction from W to U and in the direction from W to V at the same time. A potential difference Vu-v between a U phase and a V phase in which the phase and magnitude of voltage drop due to inductance are equal is detected. Based on the detected potential difference Vu-v, a magnetic flux estimation signal ?u-v is calculated by an integrator.

Abstract: A driving device for three-phase alternating current synchronous motors controls state of charge of a capacitor, and a three-phase alternating current synchronous motor is started prior to the operation of the synchronous motor. Prior to control by a normal operation control unit, the state of charge of the capacitor is controlled by an initial state control unit and a synchronization control unit. Passage of large current through the capacitor immediately after the start of the execution of control by the normal operation control unit is suppressed. As a result, the operating state of the three-phase alternating current synchronous motor does not become unstable and the execution of control by the normal operation control unit can be started with the output voltage of the capacitor stable.

Abstract: A motor driving apparatus has a loss-of-synchronism monitoring circuit that monitors the rotation of a rotary machine such as a brushless DC motor to detect a sign of transition to a state of loss of synchronism. When the sign is detected, an energization control circuit temporarily stops driving of the rotary machine to bring it into a free running state, and thereafter carries out control so as to resume driving of the rotary machine. Further, the motor driving apparatus has an inverter and a drive control circuit that controls switching operation of the inverter based on rotation of the rotary machine.

Abstract: A robust method for detecting a relative position of a feedback device, such as an encoder or resolver, coupled to a shaft, such as a motor shaft, is provided. To detect the relative position, electrical commands are issued in an open loop mode to spin the motor shaft an amount greater than the apparent rotational angle between two consecutive markers of the position feedback device, such that the net mechanical rotation is equal to or greater than the total rotational angle between two consecutive markers.

Abstract: An apparatus for use with a flight control actuator and method for assembling the same is provided. The apparatus includes a motor drive system and a control unit. The motor drive system includes a capacitor-based energy storage configured to store and provide energy within or proximate to the actuator. The control unit is coupled to the motor drive system and is configured to facilitate managing power within or proximate to the actuator.

Abstract: A method for controlling starting of a motor is described, which is mainly applicable to estimate a possible initial position of a rotor of a motor by detecting a rotor rotation signal of the motor, and find out a most possible initial position of the rotor after making statistics. In the method for controlling the starting of the motor, a starting angle position region of the motor is calculated simply by using the rotor rotation signal of the motor, without additionally arranging a Hall sensor, so as to save a cost of a Hall device and an assembling cost. Furthermore, accuracy for estimating the starting position region can be increased according to an accuracy specification of products, thereby achieving a high flexibility.

Abstract: A motor control unit or a semiconductor integrated circuit device for an air conditioner is provided.

Abstract: A control method of a current limit of a DC motor includes generating a reference voltage according to a preset current limit value of a DC motor; comparing the reference voltage with the voltage drop of a power control switch which drives the DC motor to generate a compare result; and controlling the power delivered to the DC motor according to the compare result in order to limit the current of the DC motor.

Abstract: A BEMF detection circuit generates a rotation detection signal indicating a comparison result between electromotive force voltages VU through VW which occur at a terminal of respective multiple coils and an intermediate-point voltage VCOM. A rotor position detection circuit generates a rotor position detection signal indicating a stopped rotor position An internal start-up synchronization signal generating unit generates a predetermined-frequency forced synchronization signal. Upon receiving a fan motor start-up instruction, a driving signal synthesizing circuit generates a driving control signal based upon the rotor position detection signal. Thus, (1) when back electromotive force voltage occurs, a sensorless driving operation is started based upon the rotation detection signal; (2) when it does not occur, the driving control signal is generated based upon the forced synchronization signal. Subsequently, when it occurs, the sensorless driving operation is started based upon the rotation detection signal.

Abstract: A mechanism for a motor controller for engaging a spinning motor is provided. A power section is configured to provide power to the motor. A control is configured to control the power section. The control is configured to search for a motor frequency of the motor by applying a small excitation voltage to the motor, and the excitation voltage is initially applied at a voltage frequency which is a maximum frequency. The control is configured to track the motor frequency until the motor frequency is below an equivalent speed command and engage the motor by applying a higher voltage to the motor.

Abstract: Method for starting a single-phase synchronous electric motor using permanent magnets with simple and cost-effective implementation, said method comprising a step of application of a control logic of the switch that provides a first and a second condition for switching on: the first condition being verified when a detected counter electromotive force signal has the same sign as an electrical grid voltage signal; the second condition being verified when said counter electromotive force signal has the same sign as its first derivative value.

Abstract: A motor control apparatus has a start control section. When the motor control apparatus receives a motor start command from a host control unit when a motor is in a stop state or a low-speed rotating state where a sensorless control cannot be applied, the control section starts the motor that rotates a vehicle fan by a forced commutation which supplies a pseudo sinusoidal drive signal caused by a complementary PWM control. Thereafter, the motor control apparatus switches over to a sensorless control using a rectangular wave drive signal at an energization angle of lower than 180°.

Abstract: A phase current estimation device of a motor includes: an inverter which uses a pulse width modulation signal to sequentially commutate an electric flow to a motor of a three-phase alternating current; a pulse width modulation signal generation unit generating the pulse width modulation signal from a carrier signal; a control unit performing a startup control and a self control of the motor using the inverter; a direct current sensor detecting a direct current of the inverter; and a phase current estimation unit estimating a phase current based on the direct current detected by the direct current sensor.

Abstract: A sensorless method for starting a three-phase brushless direct-current motor includes generating a start-up control signal, a start mode selection signal, and a control signal commutation period; switching to a start mode according to the start mode selection signal; implementing a position aligning procedure according to the start-up control signal and the control signal commutation period; detecting a zero crossing point of back electromotive forces during each control signal commutation period; outputting a sensorless mode selection signal while detecting the zero crossing points of the back electromotive forces during consecutive control signal commutation periods; switching to a sensorless mode according to the sensorless mode selection signal; and detecting a zero crossing point of back electromotive forces in the sensorless mode to determine a starting result of the three-phase brushless direct-current motor.

Abstract: A method for starting a brushless DC motor. A rotor is aligned with a stator in accordance with a predetermined phase. After alignment, the rotor is positioned in accordance with another phase, two phases are skipped, a timer is set to a first count time, and the rotor is aligned with the stator in accordance with a third phase. Then the timer is restarted and the rotor is aligned with the stator in accordance with a fourth phase. After a first delay, first back electromotive force value is stored. The timer is stopped when the first back electromotive force value substantially equals a peak amplitude of opposite polarity. The timer is updated to a second count time that is substantially equal to a time at which the second timer was stopped. The process is repeated until the rotor has a position and a velocity that are suitable for normal operation.

Abstract: Startup of motor is reliably executed and sonic noise is reduced. A control circuit controls a selector to apply control to output a full-drive waveform at startup and then output a PWM modulation waveform. The full-drive waveform which is an alternating waveform in which positive and negative are inverted at 180° is output. Then, the PWM drive waveform is selected.

Abstract: A single phase DC brushless motor controller, including: a micro control unit including: a Pulse Width Modulation (PWM) pin for receiving a PWM signal from a system; and a commutation logic unit for controlling the speed and rotation of a single phase DC brushless motor according to the PWM signal.

Abstract: A braking action of movement of a support surface on an examination may be accomplished with a motor. The examination table includes a base, a support surface moveable with respect to the base, and a motor having a rotor and a stator. The motor is coupled to the support surface and configured to move the support surface. A motor controller of the examination table is in electrical communication with the motor. The motor controller is configured to brake the movement of the support surface by terminating power to a plurality of windings of the stator of the motor for a predetermined amount of time, and, selectively activating a subset of windings of the plurality of windings of the stator for a predetermined amount of time.

Abstract: A boot-strap capacitor pre-charge algorithm prevents unwanted motions in an examination table using a brushless direct current motor. The motor is supplied with power by a motor drive circuit which includes a high-side transistor coupled to a high-side gate driver, a low-side transistor coupled to a low-side gate driver, and a boot-strap capacitor coupled with the high-side gate driver. A control panel is provided that communicates with a motor controller. When the motor controller receives an indication that the motor is to be started, the motor controller activates a low-side gate driver to switch on the low-side transistor, thereby causing the boot-strap capacitor to charge. The motor controller then deactivates the low-side gate driver to switch off the low-side transistor and activates the high-side gate driver to switch on the high-side transistor, causing a voltage to be supplied to a stator of the first motor and/or second motor.

Abstract: A method of the Pulse Amplitude Modulation for the Sensorless Brushless motor, which includes a start-up circuit, a phase detect circuit, a phase commutation circuit, a driving circuit, BEMF detection circuit, and frequency detector, utilizes the control signal of the phase commutation circuit to control the driving circuit so as to drive the outer motor coil and detect the control signal for the driving motor driving circuit by a detection circuit. The motor system can be controlled to reduce the discharge speed to avoid the motor driving circuit shutdown and further speed up the start-up time for the next charging period of the motor driving circuit to achieve the effect of low speed rotation and power saving.

Abstract: Identification without shaft encoder of electrical equivalent circuit parameters of a three-phase asynchronous motor comprising: standstill position search of the rotor, so that the d flux axial direction of the rotor is aligned opposite the ? axial direction of the stator; test signal voltage supply U1d in the d flux axial direction of the motor whereby the q transverse axial direction remains without current; measuring signal current I1d of the d flux axial direction of the motor; identification of equivalent circuit parameters of the motor based on the test signal voltage U1d and on the measuring signal current I1d in the d flux axial direction; whereby the rotor remains torque-free. The method used to control electrical drives. An identification apparatus for a synchronous motor and a motor control device comprising the apparatus, whereby identified equivalent circuit parameters can be used to determine, optimize and monitor a motor control.

Abstract: An anti-noise method for the Direct Current Brushless motor System, which includes a startup circuit, phase detective circuit, motor phase commutation circuit, driving circuit, BEMF detective circuit, and frequency detector, utilizes the BEMF detective circuit to detect the BEMF induced from the coils of the outer motor, and utilizes the sampled voltage phase to determine rotation speed and phase of the external motor by the phase detection circuit and frequency detector. Further, the sampling voltage of the BEMF detection circuit is feedback controlled by the frequency detector, utilized to keep good BEMF to noise ratio, and avoids the BEMF sampling error from the system.

Abstract: Systems and methods are provided for pulse-width modulated control of power inverter using phase-shifted carrier signals. An electrical system comprises an energy source and a motor. The motor has a first set of windings and a second set of windings, which are electrically isolated from each other. An inverter module is coupled between the energy source and the motor and comprises a first set of phase legs coupled to the first set of windings and a second set of phase legs coupled to the second set of windings. A controller is coupled to the inverter module and is configured to achieve a desired power flow between the energy source and the motor by modulating the first set of phase legs using a first carrier signal and modulating the second set of phase legs using a second carrier signal. The second carrier signal is phase-shifted relative to the first carrier signal.

Abstract: A triphase rotating electric machine includes three coils evenly distributed around a rotational axes of the machine, and at least one first sensor, capable of generating a periodic signal to represent the position of the machine around the axle and a control circuit capable of controlling, when in the first mode, the conduction of a switch (KUH), linked to at least one of the three coils based on the periodic signal generated by the first sensor (U), such that the conduction phases of the switch (KUH) have a duration in the order of half the signal period (U). The control circuit is capable of controlling switch (KUH), based on a second mode in which the conduction phases of the switch (KUH) have a duration in the order of a third of the signal period (U).

Abstract: A brushless motor control device according to the present invention drives a brushless motor including a stator having coils of three phases U, V, and W and a neutral line, and a sub coil provided in any one phase of the phases U, V, and W, for detecting a voltage induced in the coil of the one phase, and the brushless motor control device carries out a conduction control function, for the respective phase coils of the brushless motor, that performs a 120° conduction when a rotation speed of the brushless motor is lower than or equal to a predetermined rotation speed, and that performs a 180° conduction when the rotation speed is higher than or equal to the predetermined rotation speed, and the brushless motor control device includes a motor control unit that controls the brushless motor based on information of the rotor stop position when activating the brushless motor, controls the brushless motor based on the first rotor position information when in the 120° conduction, and controls the brushless motor bas

Abstract: Method for starting a single-phase synchronous electric motor using permanent magnets with simple and cost-effective implementation, said method comprising a step of application of a control logic of the switch that provides a first and a second condition for switching on: the first condition being verified when a detected counter electromotive force signal has the same sign as an electrical grid voltage signal; the second condition being verified when said counter electromotive force signal has the same sign as its first derivative value.

Abstract: A motor speed determining circuit determining a rotation speed of a motor is provided and a processing of generating motor driving waveform is switched in accordance with the rotation speed of the motor. A resolver signal outputted from a resolver 2 is converted to a digital value by an R/D converter 3, and inputted to a computing circuit of resolver value correction 5 via an R/D conversion interface 4. A current value of a motor M is converted to a digital value by an A/D convertor 8. The computing circuit of resolver value correction 5 computes a resolver correction value of the inputted digital signal and calculates positional data from a corrected resolver value. The computing circuit of motor control computes a current instruction value from a motor current value subjected to digital conversion by the A/D converter 8 and a motor current instruction value etc.