Abstract: The disclosed invention achieves a significant reduction in the noise and vibration of a brushless motor from a startup up to the number of steady revolutions. To drive the brushless motor from stop up to the number of steady revolutions, when the arithmetic sequencer detects a rise of a clock signal CARYCLK, current control arithmetic is executed. On detecting a fall of the clock signal, the arithmetic sequence determines whether a division control signal DIVCNT has changed. If this signal has changed, soft switch arithmetic is executed. When the division control signal has not changed or after the completion of soft switching arithmetic, the arithmetic sequencer determines whether a rise of a mask signal MASK has occurred during one cycle of the PWM carrier signal CARYCLK. If a rise of the mask signal has not occurred, the operation returns to the first step. If a rise of the mask signal has occurred, PLL control arithmetic is executed, then the operation returns to the first step.

Abstract: The electric motor includes a coil array having a plurality of magnetic coils; a magnet array having a plurality of permanent magnets; a magnetic sensor outputting an output signal that changes in analog fashion depending on relative location of the magnet array and the coil array; a drive control circuit; and an output waveform correcting unit. The output waveform correcting unit corrects the waveform of the output signal of the magnetic sensor based on the voltage level of the output signal of the magnetic sensor, in such a way that the output signal of the magnetic sensor is shaped to prescribed waveform shape during operation of the electric motor.

Abstract: An energization signal generating circuit respectively compares back electromotive forces generated in coils of each phase of a motor with a midpoint voltage of each phase, and generates energization signals. A pulse signal generating circuit generates a pulse signal in which duty ratio is controlled according to torque. A ramp signal generating circuit divides, into a plurality of times, a period of a frequency generation signal obtained by synthesizing the energization signals, and, for each divided time unit, generates a ramp signal in which pulse width gradually changes, and which has a frequency the same as the pulse signal. An output circuit supplies a drive current to the coils of each phase, based on the energization signals, the pulse signal, and the ramp signal.

Abstract: A brushless motor control system according to the present invention detects a rotor stop position when activating the brushless motor including a stator having coils of three phases U, V, and W, and controls a phase voltage for energizing the coils of the respective phases U, V, and W, and the brushless motor includes the stator having coils of phases U, V, and W of N (N?2) poles, in which any one phase coil among the coils of the phases U, V, and W is removed in one of the N poles, and the brushless motor control system includes: a current rise detecting circuit that, when the brushless motor is in a stop state, sequentially selects coils of two phases from the coils of the respective phases U, V, and W, applies a predetermined direct current voltage between the selected coils of the two phases, and detects a value of an electric current flowing to the selected coils of the two phases; and a rotor stop position detecting unit that determines a rotor stop position of the brushless motor based on information o

Abstract: An electrical machine having a stator and a rotor. The stator includes a core and a plurality of windings disposed on the core in a multiple-phase arrangement. The rotor is disposed adjacent to the stator to interact with the stator. A method of operating the motor includes applying a pulsed voltage differential to first and second terminals of the windings resulting in movement of the rotor; monitoring the back electromotive force (BEMF) of the windings to sense rotor movement; after the applying and monitoring steps, monitoring the BEMF of the windings to determine whether the rotor is rotating in a desired direction, and electrically commutating the motor when the rotor is rotating in the desired direction and zero or more other conditions exist.

Abstract: An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position even though power source voltage fluctuates is provided. First, the power source voltage is detected, and voltage is supplied only for a certain period of time and a current response is detected. The current detection value is multiplied by the ratio of a reference voltage to the power source voltage detected to correct the current detection value. Specifically, the peak current detection value is corrected upwardly or downwardly in each direction. A voltage supplying direction in which the current detection value is maximized is searched for to estimate the rotor position and a brushless motor is started.

Abstract: System and method for aligning and initiating rotation of a rotor in a motor. The motor may include the rotor and a plurality of pairs of electromagnets. The energy needed for alignment of the rotor of the motor may be used to generate the first movement in forced commutation. The energy needed for alignment may be combined with the initial energy to start the motor. The logic may be configured to align the rotor of the motor by energizing the three coils of the motor. Pulse width modulation may be applied to the first coil to control current on the coils; when a maximum PWM duty cycle is reached, the coil not required to rotate the correct direction may be released, thereby initiating motion in a rotor of the three phase motor. A rotation period may be determined. One or more pairs of electromagnets of the plurality of pairs of electromagnets may be excited at a first excitation level. The excitation level may be increased, over a second period of time, to a second excitation level.

Abstract: A location system is configured for determining a magnetic pole position of a motor. The location system includes a motor driver, a current control module, a current feedback apparatus, a speed feedback apparatus, and a magnetic pole position location module. The current control module is configured for set current of the motor via the motor driver. The current feedback apparatus is configured for sensing an actual current of the motor. The speed feedback apparatus is configured for sensing an actual speed of the motor. The magnetic pole position location module is configured for inputting a magnetic pole position of the motor, receiving the actual current from the current feedback apparatus, receiving the actual speed from the speed feedback apparatus, and processing the actual current and the actual speed to obtain an initial magnetic pole position.

Abstract: An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position is provided. The apparatus may be used as a start-up system for brushless motors. The apparatus performs accurate estimation even though power source voltage fluctuates, and is able to provide compact configuration. The apparatus supplies voltage to the coils respectively. In each supplying period, the apparatus counts voltage supply period of time until current value reaches to a current threshold value. Since a coil indicative of rotor stop position is prone to be magnetically saturated. The apparatus estimates the rotor stop position based on the voltage supply periods. Then, the apparatus starts a switching sequence based on the rotor stop position.

Abstract: A disk drive is disclosed comprising a disk, a head actuated over the disk, and a spindle motor for rotating the disk, wherein the spindle motor comprises a plurality of windings. During a spin-up operation of the disk, a sinusoidal driving signal is applied to each winding of the spindle motor for a spin-up interval, wherein during at least eighty percent of the spin-up interval the sinusoidal driving signals are applied to the windings of the spindle motor open loop.

Abstract: A soft-start circuit includes a power source, a switch, a capacitor and a regeneration brake circuit. The regeneration brake circuit absorbs a return current. The regeneration brake circuit includes a resistor, a diode and a transistor. The resistor is connected between two poles of the power source via the transistor. The diode is connected between the resistor and the positive pole of the power source via the switch. The capacitor is connected between the negative pole of the diode and the transistor. The switch is connected between the negative pole of the diode and resistor. When the switch turns off, the power charges the capacitor via the resistor and the diode of the regeneration brake circuit. When the switch turns on, the return current turns the transistor on, and the resistor absorbs the return current.

Abstract: A trigger mechanism for starting current acquisition for motor control applications is disclosed. The present invention may generate an edge (ADC trigger) that can be used to start current acquisition by the ADC. The present invention may reduce the overhead involved in synchronizing the current acquisition with PWM generation and also minimize the wait period for software conversions to complete by replacing software-based timing with a hardware-based trigger mechanism.

Abstract: A motor control device includes a dq-axis current control unit for generating a dq-axis voltage reference based on a dq-axis current reference and a dq-axis current signal, an initial magnetic pole position estimation unit for estimating a magnetic pole position of the motor upon power-on to generate a magnetic pole position signal, and a magnetic pole position estimation precision confirming unit for supplying a current in a d-axis direction after generation of the magnetic pole position signal with the initial magnetic pole position estimation unit, and checking an error of the magnetic pole position signal based on an angle of movement of the motor.

Abstract: A fan is electrically connected with an alternating current power source. The fan includes an impeller, a motor and a controlling device. The controlling device includes a commutating unit, a magnetic detecting unit, a first switching unit, a second switching unit, a third switching unit and a controlling unit. The alternating current power source is electrically connected with the first switching unit, the second switching unit and the commutating unit, respectively. The commutating unit is electrically connected with the magnetic detecting unit and the controlling unit, respectively. The controlling unit is electrically connected with the third switching unit and the first switching unit, respectively. The third switching unit is electrically connected with the second switching unit. The first switching unit and the second switching unit are electrically connected with the motor, respectively. A controlling device of the fan is also disclosed.

Abstract: The invention relates to a drive device (100) for use in a laboratory device, having a stepping motor (10) having rotor and stator, and having a motor controller (20), which is designed for the purpose of activating the stepping motor (10). In one embodiment, the drive device (100) comprises an encoder (11), which supplies a respective current encoder signal (e(t)) in operation (ia, ib), which reflects the current rotor position of the rotor, and phase terminals (14, 27), to tap the currently flowing motor phase currents (ia, ib). The motor controller (20) comprises a transformation module (13), in order to decompose the currently flowing motor phase currents (ia, ib) using a transformation method into a slip component (ix) and a torque component (iy).

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: Various systems and methods for controlling DC motors are disclosed herein. For example, one method provides for controlling a polyphase, brushless DC motor. The method includes providing a DC motor that has a plurality of phases. Such a DC motor operates by inducing a current in the plurality of phases in accordance with a plurality of commutation states. In the example, six commutation states are discussed, but fewer than or more than six commutation states may exist. The method further includes initializing a count, inducing a current in the plurality of phases in accordance with a first commutation state, and incrementing the count until the current achieves a threshold in the first commutation state. Then, a current is induced in the plurality of phases in accordance with a second commutation state, and the count is decremented until the current achieves the threshold in the second commutation state.

Abstract: At an initial drive operation after turning on of an electric power source, an ECU sequentially changes each current exciting phase among multiple phases through one complete cycle at a predetermined time schedule, so that a rotational position of a rotor and the corresponding exciting phase coincide with each other at some timing during the initial drive operation, and thereby the rotor is rotated. The ECU counts the A-phase signal and the B-phase signal during the rotation of the rotor in the initial drive operation and learns a relationship among a count value of the A-phase signal and the B-phase signal, a rotational position of the rotor and each exciting one of the plurality of phases at an end of the initial drive operation. When the ECU determines that a result of the learning is erroneous, the ECU re-executes the learning by re-executing the initial drive operation.

Abstract: According to one embodiment, a controller of a motor includes a driving signal output module, a position detector, a determiner, and an over current detector. The driving signal output module is configured to generate a driving signal for generating a driving current of a motor, a duty ratio of the driving signal being depending on an over current detection signal. The position detector is configured to generate a position detection signal for determining an operating status of the motor by comparing an induction voltage generated by a rotation of a rotor of the motor by the driving current with a predetermined reference voltage. The determiner is configured to determine whether the motor is in a starting state where a rotating frequency of the rotor is smaller than a predetermined value or in a steady state where the rotating frequency of the rotor is equal to or higher than the predetermined value based on the position detection signal.

Abstract: Motors, such as DC motors, and methods and systems for operating a motor, are described. The motor is optionally an electronically commutated motor. The motor comprises one or more electromagnets and a controller device to control the electromagnets. The controller device is configured to calibrate the motor operation in a desired installation to determine the torque needed to achieve a desired operating speed by causing the motor to ramp up to the desired speed, measuring an electric current needed to operate the motor at the desired speed, and setting a value corresponding to a first speed tap using the measured electric current. The controller device is configured to operate the motor in a substantially constant torque mode using the set value at least after the completion of the calibration operation. The motor may be configured for use in a ventilation system, such as an HVACR system.

Abstract: A method and system is provided for starting a motor which is useful, among other things, is useful for motors under unknown or variable load/inertia conditions. If a first attempt to start the motor using a first frequency ramp-up rate fails, a subsequent start attempt may be performed at a decreased frequency ramp-up rate. Iteration may be performed until starting of the motor is successfully achieved.

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: An inexpensive, productivity-enhanced single-phase AC synchronous motor in which stabilized synchronous pull-in can be carried out by suppressing generation of counter torque during a starting operation. Starting operation is performed while the energizing range of motor current is suppressed such that the energizing direction of motor current waveform lagging in a phase behind the output waveform from a detection sensor (17) is switched at at least the zero cross point of the output waveform from the sensor when the number of revolutions of a permanent magnet rotor (1) reaches a predetermined number of revolutions in the vicinity of the synchronous number of revolutions.

Abstract: System and method for initiating rotation of a rotor in a motor. The motor may include the rotor and a plurality of pairs of electromagnets. A rotation period may be determined. One or more pairs of electromagnets of the plurality of pairs of electromagnets may be excited at a first excitation level. The excited one or more pairs of electromagnets may be determined based on the rotation period. The excitation level may be decreased, over a first period of time, to a second excitation level. The second excitation level may be a lower excitation level than the first excitation level. The excitation level may be increased, over a second period of time, to a third excitation level. The third excitation level may be a higher excitation level than the second excitation level. The rotation period may be decreased over the first and second periods of time.

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: An electrically operated hydraulic pump having a pump portion and a motor portion includes rotation controlling means controlling rotation of a rotor, first rotor position detecting means detecting rotational position of the rotor on the basis of speed electromotive force induced by exciting coils, second rotor position detecting means detecting the rotational position of the rotor on the basis of magnetic field of a magnet provided at the motor portion, and motor operating condition detecting means detecting operating condition of the motor portion. The rotation controlling means switches a first rotation controlling based on the rotational position of the rotor detected by the first rotor position detecting means, and a second rotation controlling based on the rotational position of the rotor detected by the second rotor position detecting means, on the basis of a result detected by the motor operating condition detecting means.

Abstract: An apparatus and a method for driving a sensorless motor are described and shown in the specification and drawings, where the method includes steps as follows. First, a control signal is acquired, where the control signal has information of a predetermined rotational speed. Next, energy is supplied and progressively increased to the sensorless motor, so as to rotate a rotor of the sensorless motor. Then, a position of the rotor is detected. Finally, the energy is gradually regulated so that the sensorless motor is maintained at the predetermined rotational speed.

Abstract: An object of the present invention is to provide a motor driving device capable of outputting an accurate rotation signal while preventing a false detection of B-EMF in a position detecting comparator. The motor driving device includes an output circuit, filter circuit, comparison circuit, current zero ampere detecting circuit, position detecting circuit, sensorless drive arithmetic operation circuit, noise reduction current waveform generating circuit, signal synthesizing circuit, and output transistor control circuit, the comparison circuit including a comparator, polarity switching portion connected to a + terminal and ? terminal of the comparator and signal switching portion, the comparator being structured to be able to set and release an offset having a predetermined voltage value set preliminarily.

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: The start timing of the pole position inference process of the linear motor installed vertically is delayed by a predetermined time after instruction of brake release. For example, from (1) increasing of the thrust instruction value of an ASR control system up to a predetermined value, (2) the movement (falling) distance of the moving part, or (3) the moving (falling) speed of the moving part, the release condition of the brake is detected and moreover after a predetermined time, the inference process of the pole position is started. The inference process of the pole position of a synchronous motor is fit to the release timing of a brake and a malfunction of the inference process and a runaway (falling in the vertical drive) of a moving part are prevented.

Abstract: A system includes a pulse-width modulation (PWM) module, a subtraction module, an error reducing module, and a summing module. The PWM module controls switching of an inverter that powers a motor. The PWM module controls the switching based on a first angle in a first mode and a second angle in a second mode. The subtraction module determines a difference between the first and second angles. The error reducing module (i) stores the difference when a transition from the first mode to the second mode is commanded and (ii) decreases a magnitude of the stored difference to zero. The summing module calculates a sum of the stored difference and the second angle. The PWM module controls the switching based on the sum in the second mode.

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: A method serves for starting a polyphase electric motor which is operated in a star connection. The method conductively bridges at least one winding part of a phase of the motor and electrically disconnects the bridged winding part, in order in this manner, to supply a higher voltage to the remaining, electrically effective windings, and thus to increase the flow of current and thus the torque.

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: 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: A cycle counter generates a cycle signal which indicates, in the form of a digital value, the cycle of Hall signals H+ and H? that indicate the position of a rotor of a motor to be driven. An up/down counter repeatedly alternates between counting “up” and counting “down” upon detecting phase transitions that occur in the Hall signals, and generates a digital driving waveform signal having a sloping region the slope of which is set according to the cycle signal. A D/A converter receives the driving waveform signal, and converts the driving waveform signal thus received into an analog voltage. A driving unit supplies a driving voltage to the motor according to the analog voltage thus received.

Abstract: When starting a brushless motor, if the stop position of the rotor is detected between time t1 and time t2, a start-up excitation pattern in accordance with the rotor stop position is input for an initial energization time Ts1. Afterward, when the energization is stopped, a plurality of signals SL1, SL2, SL3, SL4 are generated in sequence in excitation switch timing signals in accordance with the rotational position of the coasting rotor. From these signals SL1 to SL4, the rotor position is detected using the second and subsequent signals SL2 to SL4 and then the process shifts to ordinary energization switch control. In accordance with the present invention, it is possible to start up a motor in a short time with a simple method so as to obtain a large torque during start-up.

Abstract: When it is determined that a rotor is initially in a stationary state, a current vector is applied to a coil by a vector control method so as to rotate the rotor in a forward direction from a present position of the rotor regardless of a predetermined start position of the rotor. Therefore, a motor can be stably started with less power consumption and noise/vibration.

Abstract: A compressor apparatus includes a power source (26), a shell (12; 42), an electric motor (28; 52; 100; 200) having motor windings, and a control assembly (106; 206). The electric motor (28; 52; 100; 200) is located within the shell (12; 42). The control assembly a control assembly (106; 206) provides power to the motor windings from the power source (26) in two modes. A first mode provides power to the motor windings to generate heat without producing force output with the motor (28; 52; 100; 200). A second mode provides power to the motor windings to produce force output with the motor (28; 52; 100; 200). The control assembly (106; 206) activates the first mode for a selected time period prior to activation of the second mode in order to drive out a fluid (36) to reduce a risk of a flooded compressor start.

Abstract: Method and apparatus to start a frequency converter equipped with a direct current intermediate circuit, particularly when a permanent magnet motor whose rotor is rotating at the start-up time is connected to it, wherein the frequency converter has a network bridge (10) and load bridge (11), and the load bridge has controllable power semiconductor switches of the upper and lower branch (V1-V6) and parallel connected zero diodes (D1-D6), and a direct current intermediate circuit between them, and the said frequency converter uses a current transducer placed in the direct current intermediate circuit, and the analogue current signal composed by it features samples of the measured output currents, and the diverter switches of the frequency converter's upper branch are controlled using the bootstrap method, wherein start-up is initiated by controlling the controllable power semiconductor switch of the lower branch of at least one output phase to a conductive state for one or several periods of time, preferably of

Abstract: An image forming apparatus includes: a light source that emits a light beam; a photosensitive member; a brushless motor including a stator where a plurality of coils are placed and a rotor where a plurality of magnets are placed; a rotary polygon mirror, which is rotated by the brushless motor, and which periodically deflects the light beam emitted from the light source to sequentially form scanning lines on the photosensitive member; an energization switching unit that turns on and off energizations of the coils; a voltage detecting unit that outputs a detection signal based on induced voltages that are generated in the coils by rotation of the rotor; and a control unit that controls turning on/off of the energizations by the energization switching unit based on the detection signal.

Abstract: A sensorless-brushless motor control device comprises an inverter, an inverter drive circuit that drives the inverter and a current control part that controls the inverter drive circuit according to a current command from a superior control part and includes a first order lag compensating part. The device is characterized by further comprising a control mode changeover judging part that judges changeover of a control gain of the current control part after startup of the sensorless-brushless motor in response to a motor revolution sensing signal from the inverter drive circuit and a control mode changeover part that changes over the control gain of the current control part in response to an output of the control mode changeover judging part.

Abstract: A brushless motor apparatus includes a fixedly arranged stator 14, a rotor 12 rotated in a manner sequentially excited by a plurality of excitation patterns, a magnetic-pole-position detecting magnet 16 fixed to the rotor and having twice the number of poles of the rotor, and a position detecting element 18 arranged opposite to the magnetic-pole-position detecting magnet and detecting the position of magnetic poles of the rotor, and further includes a motor drive circuit serving as a control such that when the stator is excited with a different excitation pattern between regular excitation patterns on normal operation at the time of phase matching carried out upon actuation of a power source, the rotation angle of the rotor is one-half the rotation angle corresponding to the regular excitation pattern.

Abstract: A brushless dynamo-electric machine that can be used either as electric generator or electric motor driven by sine wave pulses or by commutated DC pulses. This invention solves a cogging problem between the stator and the rotor, that is inherent in most of today's brushless dynamo's with permanent magnet poles and laminated stator poles. This cogging, in related art, is caused by salient stator poles having winding slots, or gaps, with said gaps interacting with the rotors magnetic fields, causing magnetic reluctance cogging. This embodiments stator is non-salient and has a plurality of mushroom-shaped poles, presenting a congruent periphery of the stator; that is facing the magnets on the rotor. After conjoining of the poles into a stator, all said wound windings are connected together and are terminated in two free coil ends.

Abstract: The invention relates to a method for measuring a current that flows through a motor, in which a power switch that supplies the motor with electric energy is controlled by a control unit via a pulse width-modulation signal. The pulse width-modulation signal comprises a cycle of operation and the motor current is determined in a feeder to the power switch or a feeder to the motor. Since exactly one measured value representing the motor current is sampled in each cycle of operation, this permits the provision of a method for measuring the motor current, which determines the motor current in a more rapid, more cost-effective manner than in prior art. The method is used for the motor control of direct current motors.

Abstract: A motor control strategy for a motor in a front steering system for a vehicle that reduces vibrations from the motor being transferred to a vehicle hand-wheel. The control strategy also includes operating the electric motor in a commutation freeze mode if a position error signal is less than a first predetermined threshold by sending signals to coils of the motor to prevent to the motor from rotating, operating the electric motor in a commutation normal mode if the position error signal is greater than a second predetermined threshold that is greater than the first predetermined threshold, and operating the electric motor in an angle step mode if the position error signal is between an intermediate threshold and the second threshold where the angle step mode provides a signal to the motor to move the motor forward or backward a predetermined number of motor steps, one step at a time.

Abstract: A device controller system incorporates an inexpensive Hall element to detect motion of a brushless DC motor. A magnet, which is part of a motor rotor, passes by the Hall element producing a Hall voltage each rotation. The Hall voltage is coupled through an interface port to a comparator within a process controller. A microprocessor within the process controller calculates a control response based on a comparator output signal. The interface port is rapidly configured to provide signals produced from the control response as output to device drivers on the same input-output pins that receive the Hall voltage. The device drivers produce a current through fan coils producing an update in the magnetic field of each motor phase which updates the speed of the fan according to programming within the process controller. Rapid configuring and reconfiguring of the interface port allows all necessary components of the controller system to be used with a single rotational commutation cycle.

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 method and apparatus for electronic commutation of a pulse width modulation (PWM) controlled motor involves temporarily increasing the frequency of one or more PWM drive signals applied to the motor upon the occurrence of an asynchronous commutation event.

Abstract: The start timing of the pole position inference process of the linear motor installed vertically is delayed by a predetermined time after instruction of brake release. For example, from (1) increasing of the thrust instruction value of an ASR control system up to a predetermined value, (2) the movement (falling) distance of the moving part, or (3) the moving (falling) speed of the moving part, the release condition of the brake is detected and moreover after a predetermined time, the inference process of the pole position is started. The inference process of the pole position of a synchronous motor is fit to the release timing of a brake and a malfunction of the inference process and a runaway (falling in the vertical drive) of a moving part are prevented.