Abstract: A method determines deviations between actual measured current values and setpoint current values in a number n (n?2) of parallel-connected current-regulated circuit paths for the connection of a load with an energy source. A measurement of the total actual current value flowing from the energy source to the load is effected by a precision current measuring device with a low accuracy tolerance, and the measurement of partial currents in the circuit paths is effected by standard current measuring devices with a greater accuracy tolerance, in relation to the precision current measuring device. By an adjustment of the partial currents in the circuit paths, while maintaining a constant total current, values are obtained for a n-dimensional equation system corresponding to the number of circuit paths, the resolution of which, in the knowledge of the accurate total actual current, gives the deviations in the actual values of the partial currents.

Abstract: A motor driving device includes a logic unit configured to control an electrical conduction of a motor, a reference clock signal generating unit configured to generate a reference clock signal based on a rotational speed indication signal, a rotational speed signal generating unit configured to generate a rotational speed signal based on a rotational speed of the motor, and a rotational speed feedback control unit configured to receive the reference clock signal and the rotational speed signal and control the logic unit so that the rotational speed of the motor reaches a target value. The rotational speed feedback control unit changes a feedback gain in response to the rotational speed signal.

Abstract: A control system (128) for controlling a switched reluctance (SR) machine (110) having a rotor (116) and a stator (118) is provided. The control system (128) may include a converter circuit (122) operatively coupled to the stator (118) and including a plurality of switches (132) in selective communication with each phase of the stator (118) and a controller (130) in communication with each of the stator (118) and the converter circuit (122). The controller (130) may be configured to determine a position of the rotor (116) relative to the stator (118), and generate a modulated switching frequency (152) based on the rotor position.

Abstract: A motor controlling device is provided that controls a brushless motor having a plurality of phases based on magnetic pole signals output by a plurality of magnetic pole signal output sections each corresponding to one of the phases. The motor controlling device includes an abnormality determining section, a signal generating section, and a motor controlling section. The abnormality determining section determines whether a magnetic pole signal output by each magnetic pole signal output section is an abnormal magnetic pole signal. When the abnormality determining section determines that at least one of the magnetic pole signals is an abnormal magnetic pole signal, the signal generating section generates a simulated signal corresponding to the abnormal magnetic pole signal based on the normal magnetic pole signals other than the abnormal magnetic pole signal and the rotational state of the brushless motor.

Abstract: Disclosed is a method for suppressing a speed ripple occurring during an operation of an AC motor by using a torque compensator based on an activation function. The method includes the steps of calculating a speed error ?err based on a reference speed ?ref and an actual speed ?act; calculating a controller output Trm by using the speed error ?err as an input of a PI control and an operation of a compensated torque Tcom; and determining a torque variation based on the controller output Trm and a reference torque Tref and operating the torque variation in relation to an anti-windup gain Ka to use torque variation as an input of an integral (I) control. The method suppresses the speed ripple by compensating for the torque ripple through a controller which calculates the compensated torque by taking the signs of the speed error and the differential speed error into consideration.

Abstract: Apparatus to exercise electrical motor drivers by electrically simulating a geared electric or electrical motor by providing an electronic load for the power signals that are applied to it. Current levels in the load are monitored in real-time using gate array logic and digital signal processing (DSP) algorithms to determine torque, acceleration, velocity and/or position data of the motor and gear train. Motor and gear train positional signals are generated and fed back to the motor driver device to close the servo loop. Control algorithms within the gate array and DSP accurately simulate the motor inertia and act to simulate a physical motor under varying load conditions. A control interface modifies critical motor parameters such as inertia, losses, gear ratio, and loading.

Abstract: When the fan inserted in the fan header is a 4-pin fan, the control chip outputs PWM signals with different duty factors to the control pin of the fan header, to automatically change the rotary speed of the 4-pin fan. When the fan inserted in the fan header is a 3-pin fan, the control chip outputs the PWM signals whose duty factor changes with temperature of a chip under the fan to control the first power source to provide a voltage to the adjusting circuit. The adjusting circuit rectifies the voltage output from the first power source as an analog voltage signal to the control circuit. The control circuit controls the third power source to output a changeable driving voltage to the power pin of the fan header to control the rotary speed of the 3-pin fan.

Abstract: Methods and apparatus are provided for sensing currents on a plurality of phases and determining current information therefrom. The multi-phase boost converter includes a single sensor coupled to all of the plurality of phases and a controller coupled to the sensor for determining the current information in response to currents on each of the plurality of phases sensed by the sensor. The sensing method utilizes the gate drive signals and the DC current sensor output to calculate the currents on each of the plurality of phases sensed by the sensor.

Abstract: An electronic control circuit for a brushless motor has an input power circuit providing a DC voltage and a microcontroller integrated circuit receiving the DC voltage. The microcontroller integrated circuit provides three-phase control signals according to a space vector control method. A microprocessor connected to the microcontroller integrated circuit executes supervisory control over the electronic control circuit. An inverter circuit receives the three-phase control signals from the microcontroller integrated circuit and provides driving signals to the brushless motor based on the three-phase control signals received from the microcontroller integrated circuit.

Abstract: A power converter circuit for providing maximum utilization of a DC bus voltage to a two-phase Permanent Magnet Synchronous Motor (PMSM) is disclosed. The circuit includes first, second, and third nodes, each node being the junction between series connected high and low side switches connected across a DC bus; a PMSM having first and second windings and a star point at which the first and second windings are coupled to each other, the first winding having a terminal connected to the first node, the second winding having a terminal connected to the second node, and the star point being connected to the third node; and a controller for performing a three-point Pulse Width Modulation (PWM) coupled to a gate of each switch.

Abstract: A method is proposed for supplying electrical power to a DC motor (16) which can be commutated electronically via a semiconductor power output stage (28), preferably a three-phase DC motor, through which a control unit (22) passes current in blocks, corresponding to the signals from a rotor position sensor (20). Current is passed through the motor (16) variably in steps, in such a manner that the magnitude and/or the duration and/or the trigger angle of the current blocks can be varied as a function of the rotation speed and/or of the load, with respect to the profile of the induced voltage (E).

Abstract: Disclosed is a starting device and method for eliminating a peak current introduced when an inductive circuit such as a motor or a direct-current (DC) motor is actuated, The starting device includes a signal generator electrically connected to the inductive circuit and generating a first signal corresponding to a signal output by the inductive circuit, a comparative circuit electrically connected to the signal generator for converting the first signal to a second signal to be compared with a reference signal to generate a control signal, and a controlling device electrically connected with the inductive circuit and the comparative circuit for receiving the control signal and gradually increasing a current input into the inductive circuit corresponding to the control signal, thereby eliminating the peak current introduced when the inductive circuit is actuated.

Abstract: Information indicative of the placement of spindle motor components may be obtained and used to provide a correction to one or more BEMF-derived attributes used to control the spindle speed. In some implementations, first and second signals indicative of BEMF of different stator windings may be used to determine a speed-related characteristic. The speed related characteristic may be used to determine an error amount, which may be used to determine a correction factor to control the speed of the spindle motor.

Abstract: A method is specified for controlling a polyphase brushless electric motor, wherein the motor phase currents which are associated with the phases are produced by clocked variation of the respectively applied electrical potential. In this case, the motor phase currents flow back from the electric motor via a common return line with the peak current value in the return line being detected and being included in a controlled variable. Furthermore, a circuit configuration is specified, which is provided in a corresponding manner in order to carry out the control method. The control method and the circuit configuration allow the motor phase currents to be taken into account in the control of the electric motor in a simple and cost-effective manner.

Abstract: A motor driving apparatus is provided which can minimize ripple current flowing through a DC link capacitor, and downsize the motor driving apparatus. It synchronizes the frequency of the inverter carrier signal for driving an inverter with the frequency of the DC/DC converter carrier signal for driving a DC/DC converter, and carries out control in such a manner that the center of a period during which the input current of the inverter is zero and the center of a period during which the output current of the DC/DC converter is zero are matched.

Abstract: A fan speed control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a phase compensation unit. The PWM signal generating circuit generates a PWM control signal with a sequence of alternating on-time and off-time, and the driving circuit outputs a driving signal according to the PWM control signal to a fan motor. The phase compensation unit is connected to the fan motor for delaying or advancing the PWM control signal by a phase angle to synchronize the acting period of the back electromotive force formed by the magnetic flux variation with the off-time of the PWM control signal.

Abstract: A vector control device of a winding field type synchronous machine with which even when voltage changes caused by resistance voltage falls and inductance fluctuations due to armature current occur the armature voltage is controlled exactly to a desired command value and a high power supply utilization percentage is maintained at all times. An absolute value of armature voltage is calculated from an armature voltage command value or an armature voltage detected value, and the armature voltage is controlled by a flux command being regulated so that this absolute value of armature voltage approaches a desired armature voltage command value. Also, the armature voltage command value is regulated so that the loss of the synchronous machine becomes minimal with reference to the armature current and the field current.

Abstract: A fan speed control includes a power adapter, a CPU programmed with a phase splitting program, a current-limit resistor, a capacitor, a TRIAC, and a switch module, the CPU having a signal input terminal connected in series to the power input terminals of the power adapter through the current-limit resistor to obtain synchronous signal frequency as input signal, a signal output terminal connected in series to the capacitor and then the gate of the TRIAC for enabling the CPU to control triggering of the TRIAC, the TRIAC having the gate connected in series to the capacitor, and the anode and cathode respectively connected to the fan motor and the power output terminal of the power adapter, so that the fan motor, the TRIAC and the power adapter form a loop in which the TRIAC controls the operation speed of the fan motor; the switch module having one end connected to the control input terminal of the CPU for controlling the output state of the signal output terminal of the CPU and the other end connected to the po

Abstract: When a signal level of a motor brush switching signal is low and thus dropouts or omission of the pulse signals converted by a waveform shaping part take place, so that an interval between a pulse signal to be currently counted and an immediately preceding pulse signal thereof becomes longer than a predetermined average interval, a pulse signal counter makes a correction of the number of counts by adding one pulse to the pulse to be counted. Therefore, even if the signal level of the motor brush switching signals generated from a vertical motion motor M2 is low for some reasons, accurate control can be exercised over the number of rotations of the vertical motion motor M2.

Abstract: Disclosed is an electronic pulse width modulation (PWM) regulator of a low frequency rectangular wave signal serving to control the speed of a direct current motor. The invention aims at simplifying the design of said regulator by eliminating the classical inductive element so that the motor continuously operates as a filter of the output signal provided by the switching component. The invention also aims at preventing noises caused by switching. To this end, subsonic switching frequencies of less than 50 Hz are used.

Abstract: A control system in the form of an all-digital phase-locked loop controls movement of a DC motor. The control system includes a movement detector in the form of an optical encoder to detect movement of a DC motor. A digital phase detector compares output of a feedback signal from the movement detector and a reference signal. The digital phase detector is phase frequency detector that follows a describing function to model non-linear components of the reference signal. A digital loop filter then filters noise from the comparison signal and the filtered signal is amplified to control the DC motor. The phase frequency detector includes a state machine to track a time varying reference signal and selectively output a response to provide for system damping.

Abstract: The invention concerns an arrangement for powering a load (12) that has non-continuous power consumption from a DC power supply (UB). The arrangement has a DC link circuit (14, 22) to which said load (12) can be connected and with which is associated a capacitor (21) that is suitable for briefly supplying energy to the load. A current regulator (24, 30) is provided for connecting the DC link circuit (14, 22) to the DC power supply (UB) in order to deliver a substantially constant current (i) to said capacitor (21) and to a load (12) connected to the link circuit. The target value of said current regulator (30) is adjusted adaptively, by means of a second regulator (34), to the instantaneous power demand of the load (12). An arrangement of this kind can also be referred to as an active filter that is particularly suitable for electronically commutated motors and for motors with a PWM current controller.

Abstract: A system for controlling the rotational speed of a fan, according to a reference clock having a reference frequency, is disclosed. The rotational speed corresponds to a fan rotational speed signal. The fan rotational speed controlling unit compares the reference clock with the fan rotational speed signal, to output a speed controlling signal. The Voltage generating circuit generates a level signal corresponding to the speed controlling signal. The driving unit generates a driving signal to control the rotational speed of the fan according to the level signal. When the fan is assembled with the controlling system, only coils with the same number of turns need to be use to obtain various rated rotational speeds of fans of different specifications by altering the reference frequency of the controlling system. Because coils with different number of turns are not required in stock at the same time, the time cost and the manufacturing cost can be reduced.

Abstract: A controller for controlling a BLDC motor controller includes a drive assembly, and a processing element. The processing element is in electrical communication with the drive assembly and the BLDC motor, and the processing element is capable of controlling operation of the drive assembly. The drive assembly, is in electrical communication with a power supply and the BLDC motor. The drive assembly includes a plurality of half-bridge assemblies that each include two switching elements, such as insulated gate bipolar transistors (IGBT's), that are each capable of operating at no more than a predetermined frequency. In this regard, at least two half-bridge assemblies are electrically connected to each phase winding of the BLDC motor such that the half-bridge assemblies are capable of providing the pulse-width-modulated input voltage to the respective phase winding of the BLDC motor at a frequency higher than the predetermined frequency.

Abstract: A method for controlling driving of a Switched Reluctance Motor (SRM) is capable of operating the SRM normally according to a phase under the normal state in case a noise is inputted to a position sensor in the SRM. In order to achieve the advantage, the method for controlling driving of a three phase SRM using a position sensor having a rate of a rotor and a stator is 6/4 or 12/8 includes the steps of generating a sensor signal according to the position of a rotor in the SRM and operating the SRM by turning on respective phases in the SRM at the point of detecting a rising edge of the sensor signal and turning off the phase at the point of detecting a falling edge of the next sensor signal.

Abstract: An electronically switched motor includes a stator-rotor assembly fitted with three-phase driving windings, a series of switches for powering the windings, and a control circuit suitable for regulating a speed of the motor as a function of a reference speed and a measured speed. The control circuit includes switch control elements to cause each switch to switch on and off in compliance with a repeated sequence selected to power the driving windings as a function of the reference speed and the measured speed. The sequence includes a succession of on/off pulses with a duty ratio. The control circuit is suitable for generating a first switch control mode for controlling the switches so that the switches are in an ON state or receive a succession of ON pulses over a first activation period and a second switch control mode for controlling the switches so that the switches are in an ON state or receive a succession of ON pulses over a second activation period larger than the first activation period.

Abstract: A method and apparatus are provided for modeling an electric motor. The method includes the steps of interpolating a flux density for each angular position within an air gap of the electric motor from a predetermined air gap and tooth magnetization magnetomotive force versus air gap flux density curve, decomposing the interpolated flux density into a set of harmonic components using a fast Fourier transform and determining a flux density error function from the decomposed set of harmonic components.

Abstract: An adaptive motion controller for driving a servo motor. The adaptive motion controller has an amplifier including a voltage command which can be set at a voltage at which the amplifier will be operated, a frequency selector which can be set at a frequency at which the amplifier will be operated, a power supply having a current feedback, and a control for driving the servo motor in a test mode wherein the voltage command is set at a selected voltage, and the frequency selector is sequentially set with a series of different frequencies. The servo motor is operated at each frequency, and the frequency of the series of frequencies that has the lowest current feedback is determined and the frequency selector is set at that frequency when the amplifier is operated to drive the servo motor.

Abstract: A servo-control apparatus for a motor includes a position detector for detecting a rotational position of a motor, a rotational speed signal generator for generating a rotational speed signal corresponding to a rotational speed of a motor, and a digital controller for generating an exciting electric current to be supplied to a coil of the motor as a pulse width modulated signal in accordance with the rotational speed signal from the rotational speed signal generator. A switching signal for switching the exciting electric current to be supplied to the coil of the motor is formed by a pre-driver in accordance with the position detection signal from the position detector, and the pre-driver combines the switching signal with the pulse width modulated signal from the digital controller to generate an electric current control signal by which the motor is driven, thereby coping with the speed change of the motor quickly and stably.

Abstract: A synchronous control device according to the present invention completes an origin matching between a master section and a slave section without causing a phase difference even when a deceleration device is employed in the master section or in the slave section so as to perform an accurate synchronous control. The synchronous control device constantly detects the phase of a shaft of a master electric motor by a phase detector of the master electric motor according to the outputs of a master rotary encoder, and the phase of a shaft of the master machine by a phase detector of the shaft of the master machine according to the outputs of a master rotary encoder and an origin detector of the shaft of the master machine.

Abstract: The invention relates to an electric drive device with a DC motor (2) comprising a control circuit with an electronic commutator (3). The invention is characterized in that a derivation of a control signal (V_i_ref) is obtained from an induced motor voltage (E_sample) detected by a measuring device and from a reference value (V_i_av) which serves to regulate the speed of the DC motor (2), and in that the derived control signal (V_i_ref) serves to achieve a substantially constant torque of the DC motor (2) through adjustment of the motor currents (ia, ib, ic).

Abstract: The invention relates to a control system for a commutator motor which is operated by phase-fired control. Allocation of a first and second control device in a single operating state without transition makes it possible to obtain constant jolting rotation of said motor by continuously varied cutting of the half-waves into first and second area sections (8,7) of an alternative current voltage. The inventive type of control system can be used advantageously in electric screwing or drilling tools.

Abstract: An apparatus for reproducing information recorded on an optical disc which can favorably accomplish a time base correction for a read signal in a simple configuration. Also, the apparatus precisely removes jitter components produced when a driving signal is supplied to a spindle motor. The apparatus has a spindle motor for rotating an optical disc, a pickup for optically reading a recorded signal on the optical disc to generate a read signal corresponding to the recorded signal, and an A/D converter for digitizing the read signal to reproduced an encoded signal. The apparatus is provided with a controller for supplying the spindle motor with driving power. The controller has an unnecessary component removing filter for removing high frequency components from the motor driving power.

Abstract: To provide a spindle motor control method adapted to an optical disk recording and reproducing apparatus capable of recording a signal onto a disk using a laser applied from an optical pick-up, a reference signal originated from a disk (1) and a reference signal necessary for signal recording are synchronized to each other when resuming signal recording once suspended. The synchronization is established without using a phase error component. Once synchronization is established, a phase error component is added to a servo signal of the spindle motor (2). A gain for a phase error component is begun gradually increasing after a phase error component is begun being added to a servo signal. An upper limit value of the gain of a phase error component to be added is determined depending on the location of a part on the disk (1) at which to resume the once suspended signal recording.

Abstract: A low cost, microprocessor (U1) based motor controller (10) for driving a half-wave, multiple speed, reversible, DC brushless motor (30) directly from standard AC 50/60 Hz power. A large number of different speed and rotation direction combinations may be chosen before or after the motor is installed using configuration resistors (Rcol1, Rrow1). SIDACs (TS2, TS3) each serially connected to a diode (D6, D5) are connected across respective coils (COIL—1, COIL—2) to clamp the flyback energy in the windings to a few volts when triggered and allow Vemf to float when not triggered. The control adjusts the relative phase timing of commutation during start-up and during running to enhance efficiency. Locked rotor protection is provided by limiting start-up time to a selected period which is followed by a selected cool-off time.

Abstract: A controller for an electric motor, includes a reference circuit and control circuitry. The reference circuit generates a reference signal having a phase and frequency determined in accordance with a set of motion parameters input to the circuit. The control circuitry receives the reference signal and receives a feedback signal from a rotation detector coupled to the motor, the detector having a predetermined rotational resolution, and compares the reference signal and the feedback signal to generate a drive signal used to drive the motor at a speed and phase of rotation determined by the frequency and phase of the reference signal. The phase of rotation of the motor is locked to the phase of the reference signal such that deviation of the phase of rotation relative to the phase of the reference signal at steady state is substantially smaller than the rotational resolution of the rotation detector.

Abstract: The motor speed control device of the present invention is provided with an FG sensor and a waveform shaping circuit for obtaining N pulse signals (N.gtoreq.1 where N is an integer) in one rotation of a motor so as to control the rotation speed of the motor in accordance with period information of the FG pulse signal outputted from the waveform shaping circuit. The motor speed control device is further provided with an FG nonuniformity correcting circuit for correcting, by using respective period information of a rising edge-falling edge period and a falling edge-rising edge period, periodic nonuniformity of each period. The motor speed control device controls the motor in response to an actual speed error signal whose nonuniformity such as a duty error and a phase error has been corrected by the FG nonuniformity correcting circuit.

Abstract: A motor having enhanced transient characteristics during the acceleration time of the motor in a disk unit. The motor includes a motor controller having a phase-locked loop (PLL) or frequency-locked loop (FLL) for controlling the speed of a spindle motor in a disk drive. The PLL or FLL is coupled to a digital filter. The difference between a phase or frequency synchronized with the rotational speed of the motor and a target value is received by the digital filter. The digital filter output is added to the target value. The sum of the filter output and the target value is set in the PLL or FLL as an adjusted target value to perform PLL control or FLL control. With this arrangement, the time to shift from a low-speed rotation state to a high-speed rotation state can be shortened.

Abstract: A frequency-locked stepping position control servo (FLSPS) system for driving a stepping motor. It essentially comprises a means for driving the stepping motor to move an object toward a target according to a driving signal, a means for detecting position of the object, a position-to-frequency converter to feedback the position information and a microprocessor-based slope-varied frequency-controlled oscillator (.mu.P-SVFCO) to generate the driving frequency. The .mu.P-SVFCO includes a microprocessor to ease the implementation of the control law and utilizes the slope-varied technique to adaptively pump the pulse train frequency of the driving signal. In addition, a one-bit clock is provided to dynamically maintain the position of the object when the target position is reached. The FLSPS system is capable of achieving similar system acquisition times for different target commands among a wide-range of positioning control commands.

Abstract: An inverter control apparatus and method for a motor driven by an inverter circuit. The primary current of the motor is detected by a detector circuit and is used in combination with a primary current command value to provide pulse-width modulation of the inverter circuit. The inverter is controlled by a switching circuit that can change the PWM frequency based on any one or more factors, including motor speed, motor speed or position control mode, equivalent load factor and detected temperature.

Abstract: A motor speed control apparatus is provided in which the controllable frequency band of the control system can be sufficiently enhanced with a comparatively simple structure even if the frequency generator equipped into the motor is low in output frequency and the rotational accuracy can be highly improved even if the disturbance of high frequency components of load torque is applied to the motor. The frequency band of the control system can be improved by using the estimated speed signal as the speed feedback signal. A motor speed control apparatus superior in disturbance control characteristic can be realized through the feed forward compensation of an estimated load torque.

Abstract: Apparatus and method for adaptively compensating for variations in rotational speed of a back emf commutated spindle motor in a hard disc drive. After the motor achieves nominal operating speed, the hard disc drive enters a learn mode during which systematic variations in operational speed of the spindle motor are characterized over a plurality of rotations, including characterization of the average timing of zero crossing signals with respect to reference frequency periods and characterization of the average time between successive zero crossing signals. The hard disc drive next enters a compensation mode, during which modified speed control timing signals and modified commutation timing signals are outputted in response to the average timing characterized during the learn mode.

Abstract: A spindle motor controlling circuit for controlling the rotation of an optical disk system using a constant linear velocity servo. The circuit includes a spindle motor rotation sensing circuit for generating a phase frequency in response to the rotation of the spindle motor. A speed control part of the controlling circuit includes a speed error signal generating circuit that generates speed error data indicative of a difference between the period of the phase frequency and data representing a desired spindle motor speed. A phase control part of the control circuit includes a phase coefficient pulse generating circuit, a reference phase signal generating circuit and a phase error signal generating circuit. Finally, the controlling circuit includes a driving voltage generating circuit for generating a speed driving voltage corresponding to the speed error data and a phase driving voltage corresponding to the phase error signal. The driving voltages are used for driving the spindle motor.

Abstract: A rotation control apparatus employing a comb filter to cut off a specified frequency and multiples thereof in response to speed error data detected from a rotation detector. A phase error detector detects a phase error between the rotation detector and an external vertical synchronization pulse. A differentiator converts the output of the filter into angular acceleration error data. The output of the phase error detector is integrated. The two values are scaled and converted to an analog signal which is utilized to drive a motor.

Abstract: A capstan motor is controlled by a signal derived from a frequency generator that has been converted to a voltage that reflects the instantaneous change in velocity of the rotating motor. Acceleration of the motor is found by using a mean velocity obtained as a reciprocal of the pulsed signal from the frequency generator and then estimating the instantaneous velocity based on the derived acceleration. The estimated instantaneous velocity is converted to a drive voltage for the capstan motor so that the motor can be started and stopped with a respective constant acceleration and deceleration.

Abstract: The present invention relates to a method and apparatus for controlling the speed of an electronically commutated motor. Such motors typically include a rotor, a stator coil, and an electronic commutator for controlling electrical power flow from an electrical power source of predetermined frequency to the stator coil.

Abstract: A motor control system includes a microcomputer for executing a so-called software servo-control, and the microcomputer receives a speed signal and a phase signal from the motor. In the microcomputer, speed error data is evaluated on the basis of the speed signal, and speed integration data is evaluated on the basis of the speed error data and a first reference signal, and phase integration data is evaluated on the basis of the phase signal and a second reference signal. The speed error data, the speed integration data and the phase integration data is synthesized, so as to obtain motor control data.

Abstract: A system and method for controlling the speed of an electric motor compares the actual speed of the motor with the desired speed of the motor. A digital comparison of the desired speed of the electric motor with the actual speed of the electric motor provides an error signal indicative of the error between the desired speed and the actual speed. A large timing current from a programmed timing control will cause an increase in the speed of the motor, while a smaller timing current from the programmed timing control will cause a decrease in the speed of the motor. In this manner, the programmed timing control affects the actual speed of the motor 12 to approach the desired speed. The programmed timing control can also provide a ramping acceleration or deceleration as the motor speed changes to approach the desired speed. The speed control system can also include a programmed stall detector which can cause the operation of the electric motor to be ceased when a stalled motor condition is detected.

Abstract: A speed controller is equipped to a step motor for controlling the rotation of the step motor with a desired angular velocity. The step motor speed controller utilizes a phase-locked stepping servomechanism (PLSS) in which a phase-controlled oscillator (PCO) comprised of an adaptive digital-pumped controller (ADPC) and a voltage-controller oscillator (VCO) is employed. The step motor speed controller utilizes a tachometer comprised of an optical encoder for detecting the angular speed of the step motor. The tachometer sends out a first pulse train with the frequency thereof indicating the angular velocity of the step motor as a feedback signal to the ADPC. A reference signal source is employed for sending a second pulse train to the ADPC. The ADPC compares the phase difference between the first pulse train and the second pulse train and whereby a signal corresponding the phase difference is sent to the VCO, causing the VCO to output a third pulse train to the step motor.

Abstract: In order to pick up in a simple manner which is reliable, and under rough operating conditions, a rotation of the rotor in a miniature motor excited by permanent magnets with magnet segments at a tangential distance with magnet segments distributed at the bore circumference of the stator, it is proposed to arrange in at least one pole gap between the magnet segment a measuring coil. A signal is induced by the pulsation of the stray field due to rotation of the rotor. The measuring coil is advantageously arranged in a non-magnetic, preferably plastic support body held between the individual poles or the magnet segments respectively.