Abstract: A control circuit for a cooling fan is provided that adjusts input power and drive a cooling fan. The control circuit comprises a temperature detector for detecting temperature; a power controller for controlling driving power to the cooling fan based on the input power and supplying the driving power; a proportional electric power block supplying control power proportional to temperature variation of the detected; and a fixed electric power block supplying control power at a fixed level when the detected temperature is lower than a predetermined level. The control circuit for a cooling fan is configured to detect temperature variation and to operate with less noise by controlling rotational velocity of the cooling fan in proportion to variation in temperature variation to reduce noise generated when operating the cooling fan.

Abstract: A voltage for driving a cooling fan is usually output from a fan voltage control circuit. Whether to cause the fan voltage control circuit to output the drive voltage or not is controlled by a system management utility (software) and a bridge controller (hardware) on the basis of temperature data from a temperature sensor. To provide for the occurrence of a failure in the system management utility or the bridge controller, a temperature comparator monitors the temperature data from the temperature sensor and instructs a fan voltage control circuit to output a drive voltage for the cooling fan in the case where the temperature rises above a given value.

Abstract: A method and apparatus for controlling the speed of a DC electric motor receives a periodic commutation signal having a fixed duration on cycle and an off cycle. The commutation signal then is modified to form a periodic modified commutation signal having substantially the same period duration as the commutation signal. The modified commutation signal has a single on cycle per period. The method and apparatus then determine a desired speed of the motor, and vary the duration of the on cycle of the commutation signal to form the on cycle of the modified commutation signal. The on cycle of the modified commutation signal has a duration that is less than the fixed duration. By varying in this manner, the rotor rotates at substantially the desired speed.

Abstract: A magnetizing motor having a permanent magnet body covering an outer circumferential surface of a rotor body, includes a speed detecting unit that detects a speed of the magnetizing motor; and a controlling unit that compares the speed detected by the speed detecting unit with a reference speed, and outputs a magnetizing control signal based on the result of the comparison.

Abstract: A fan system includes a driving device, a speed detecting device and a logic device. The driving device generates a speed detecting signal and a predetermined alarm signal. The speed detecting device, which is electrically connected with the driving device, receives the speed detecting signal, and generates a low speed signal when the speed detecting signal is lower than a reference signal. The logic device is respectively electrically connected with the driving device and the speed detecting device, and generates an alarm signal when the logic device receives the predetermined alarm signal or the low speed signal.

Abstract: The present invention relates to a method and a system for correcting references (xref), in the case of flux reduction, used in a speed variator for controlling an electric motor M having a three-phase supply, for example of the synchronous or asynchronous type. This method consists, in particular, of using a dynamic system (MM) representing a model of the motor to be controlled, provided with at least one integrator (Int) and having as input the difference between a limited value of a control voltage (u) to be applied to the motor (M) and the value of a calculated reference voltage (uref).

Abstract: A wireless system uses a direct UHF radio frequency (RF) signal to control electric trains and train accessories. A controller, such as a handheld unit used by the toy train operator, accepts control commands and transmits encoded control data over a high frequency radio link directly to a receiver, on the toy train or train accessory, which decodes the commands and controls the toy train or toy train accessory functions with either unidirectional or bidirectional communication between the controller and the model train or train accessory. One controller has the ability to control many trains and other model train layout components such as signals and track switches even while other train operators are operating their trains on the same electric train track layout.

Abstract: A system and method of restarting a switched reluctance motor after a cycling of power provided to the motor is provided that includes receiving at the motor a power-off signal followed by a power-on signal, determining a rotational speed of a rotor, and energizing a stator only when the rotational speed of the rotor is determined to be less than a threshold speed.

Abstract: A control device for a vehicular opening/closing body is provided with a duty ratio calculator (78), which calculates a duty ratio when power supplied to a door drive motor (48) allowing an opening/closing body to open/close is subjected to duty control based on a result of adding first second multiplication values, the first multiplication value being obtained by multiplying a speed difference between a target opening/closing body speed and an actual opening/closing body speed by a negative proportional gain, and the second multiplication value being obtained by multiplying an integral value of the speed difference by an integral gain.

Abstract: A barrier movement operator which uses an A.C. motor to move a barrier is disclosed herein. The operator senses a characteristic of barrier movement, such as motor rotation speed, to detect when the barrier contacts an obstruction. The motor and/or the circuitry for applying electrical power to the motor have been enhanced to improve the detectibility of contact with an obstruction.

Abstract: A self-calibrating, continuous variable speed fan for use in cooling electronic circuitry is disclosed. Upon initial power-up, in an environment of known temperature, the self-calibrating fan accommodates for the tolerances of its electronic components by reading a voltage from its thermistor array and comparing the actual value to an expected value for the given temperature. The difference is then stored in the non-volatile memory of a microcontroller for use in adjusting future voltage readings from the thermistor array. During normal operation, adjusted readings from the thermistor array are then converted by the microcontroller into a control signal for driving the motor of a cooling fan. A quickly cycling stochastic process between adjustments to fan motor speed and temperature readings is then established, thereby maintaining a high degree of control over the device to be cooled.

Abstract: Devices and methods for moisture removal from conditioned air. A speed control is provided that selectively operates the blower motor of an air conditioning system at a lower speed. The speed control may include a time delay circuit and single pole, double throw relay. The speed control is used to slow the speed of the air cycler during the initial stage of a cooling cycle. This initial stage is typically the first 5–7 minutes of the air conditioning cycle. In a further aspect, a humidistat is operably associated with the system for detection of humidity levels within the air of a home or other structure. The system is programmed to close the motorized outside air damper in the event that humidity levels exceed a predetermined level, thereby limiting further entry of humid outside air into the home.

Abstract: Embodiments of an apparatus and method can control a fan drive in a computer system. Such embodiments of apparatus and methods can alternately output a plurality of pulse width modulation (PWM) control signals at a predetermined time ratio and variably control a rotation speed of a cooling fan. The embodiments can use simple hardware based upon N-bit resolution in a PWM control signal generator included in the computer system for controlling the rotation speed of the cooling fan decreasing an internal temperature, such that the rotation speed of the cooling fan can be precisely and variably controlled, equally with the effect of an operation for controlling the fan drive using hardware based upon resolution of more than the N bits. Further, a physical configuration can be effectively simplified, and unnecessary power consumption can be reduced or prevented.

Abstract: Control parameters can be easily and precisely adjusted, the response of a motor controller can be highly accurately made at high speed and a vibration can be suppressed to a low level. Even when an inertia is varied during an operation or a viscous friction is high, the inertia or a viscous friction coefficient can be identified by a control parameter adjusting unit (18) for performing a calculation on the basis of a torque command Tref and the speed Vfb of a motor. As a result, control parameters can be easily and precisely adjusted and the response of a motor controller can be highly accurately carried out at high speed and a vibration can be suppressed to a low level.

Abstract: A method for determining motor velocity includes generating an edge signal including a plurality of edges. The edge signal indicates rotational travel of a motor. Edge counts in the edge signal occurring during periodic sample intervals are determined. The edge counts are filtered over a predetermined number of samples. A velocity feedback signal is generated for the motor based on the filtered edge counts. A drive unit for controlling a motor includes an edge detection unit, a position accumulator, and a velocity filter. The edge detection unit is operable to receive a motor position signal and generate an edge signal including a plurality of edges. The edge signal indicates rotational travel of the motor. A position accumulator is operable to determine edge counts in the edge signal occurring during periodic sample intervals. The velocity filter is operable to filter the edge counts over a predetermined number of samples to generate a velocity feedback signal for the motor based on the filtered edge counts.

Abstract: A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking resistor and a control switching element disposed in parallel in an additional line connecting the pair of connection terminals to each other, a control switching element disposed with the breaking resistor in the additional line, a breaking switch disposed to one of the connection terminals and switched to either a normal position or a breaking position connecting the one connection terminal to a corresponding supply part or to the additional line, a speed detector detecting a motor speed and a control part controlling the breaking switch to switch to the breaking position and controlling the control switching element so that an on-off interval of the control switching element is controllable depending on the detected speed.

Abstract: A method for reducing line-conducted interference in a pulse width modulated triggering system of an electric motor, a triggering pulse width modulation signal having, in one clock cycle, one or more signal edges between a first signal level and a second signal level, the pulse width modulation signal being generated in such a way that at least one of the signal edges has a first segment having a first edge slope and a second segment having a second edge slope, the absolute value of the first edge slope being less than the absolute value of the second edge slope.

Abstract: A fan control device receives a reference revolution signal to control the rotation speed of a fan. The fan control device includes a reference signal generating module, a revolution modifying module and a fan driving module. The reference signal generating module generates a first reference signal and a second reference signal. The revolution modifying module receives the first reference signal and the second reference signal, and generates a target revolution signal according to the reference revolution signal and the first and second reference signals. The fan driving module receives the target revolution signal and generates a driving signal to drive the fan according to the target revolution signal.

Abstract: A ceiling fan with an outer-rotor type DC brushless motor has a center base with multiple blades and a DC brushless motor as a driving source for the fan. The DC brushless motor includes a controller, magnetism sensors, a stator with stator windings and a rotor assembly connected to the fan and having permanent magnets interacting with the stator windings. The controller detects polarity of the permanent magnets through the magnetism sensors. Based on the detected results, the controller changes current of the stator windings to produce an inductive magnetic field with poles the same to the permanent magnets to drive the rotor assembly. Accordingly, the blades of the fan are driven to rotate.

Abstract: Rotation of a capstan motor is detected by a frequency detector, and supplied to a CPU as a rotation detection signal CFG. The CPU derives a period of the rotation detection signal CFG, calculates an average rotational speed of the capstan motor on the basis of the derived period, derives an attenuation value of the rotational speed on the basis of the calculated average speed, and thereby sets a braking time interval. As a result, calculation of the braking time using a highly accurate zero point detection with a frequency detector of one system becomes possible. The apparatus scale can be reduced.

Abstract: A fan controlling system applicable in an electronic system having a plurality of fans is disclosed. The fan-controlling system includes a first signal generating module and a second signal generating module for generating a first and a second pulse width modulation (PWM) signals according to control instructions output by the electronic system. The fan-controlling system further includes a phase-inverting module and a delay module. Therefore, PWM signals, which are delayed with a time interval one another, can be generated by the fan controlling system, so as to respectively control a plurality of fans of the electronic system, thereby avoiding the peak value of the total power signals when the fans are run from increasing instantly, and power signal for supplying the electronic system from decreasing instantly, making the electronic system run abnormally, and its stability becomes worse.

Abstract: A method and system for variable speed fan control for thermal management of a device includes disposing a first temperature sensor proximate a variable speed fan to measure an air temperature of inlet air Tair that cools the device by convection air flow. A controller is configured to compensate for changes in Tair by varying a convection coefficient (h) which is a strong function of air velocity to maintain the product of h*?T at a constant value, wherein ?T is a temperature differential between the device (TAD) minus Tair. Thus, h is varied by varying air velocity by varying a speed of the variable speed fan.

Abstract: The present invention discloses an apparatus for compensating for a speed error of a motor which can reduce a speed ripple of the motor resulting from load characteristics, and which also can reduce vibrations and noises. The apparatus for compensating for the speed error of the motor divides a rotational section corresponding to one complete revolution of a rotor of the motor into a plurality of preset rotational sections, determines a speed compensation value in each divided rotational section on the basis of a difference value between a reference speed and a previous estimated speed, and compensates for the speed error of the motor on the basis of the speed compensation value.

Abstract: An ECU executes a program including the steps of detecting a temperature TB of each battery block, calculating a desired output value VT of each motor based on a detected temperature, detecting output value V of each motor based on a signal transmitted from an F/V conversion circuit converting a pulse signal of a speed sensor provided on each motor into a voltage, reading a last DUTY command value D, calculating a difference DV between desired output value VT and output value V (DV=VT?V), calculating a DUTY command correction value for each motor based on difference DV, and adding a calculated DUTY command correction value to last DUTY command value D to calculate DUTY command value D.

Abstract: A fan control system and method that maintains the operating temperature of computer and electronic devices or components at about a predetermined control level to minimize power consumption and audible noise. The fan control system is a programmable closed loop system including a temperature sensor, first and second fan controllers, and a fan/motor assembly including a power converter, a motor, and a fan. The first fan controller provides programmable acceleration/deceleration of the fan during an initial fan spin up, and the second fan controller runs the fan only as fast as necessary to keep the sensed temperature level of a computer device as close as possible to the predetermined control level, thereby minimizing the power consumption of the system and the audible noise of the fan.

Abstract: In a motor and a disk drive apparatus in accordance with the present invention, a position detecting part 30 comprises a detection signal switching circuit 39A, a noise elimination circuit 38 and a detection circuit 39B, and the detection signal switching circuit 39A is configured to output an inverted detection signal obtained by logically inverting a detection signal until the rotation speed reaches a predetermined rotation speed after the beginning of starting or until a position detection pulse signal FG is detected a predetermined number of times; position detection operation is carried out only during the ON operation of PWM, whereby PWM sensorless starting is carried out.

Abstract: A serial fan set and rotation speed-matching curve generation method thereof are provided. The serial fan set comprises a rotation speed control module, a first fan and a second fan, in which the rotation speed control module is used to receive the power signal and produce the rotation speed driving signal corresponding to the power signal in accordance with the relations of the rotation speed-matching curve, so that the first fan and the second fan are operated at the matching rotation speed, thus producing the optimum operation efficiency and achieving the purpose of controlling the serial fan set.

Abstract: The present invention is a driving circuit for a two-phase DC brushless fan motor comprises a control unit, a Hall element, a motor and a motor protection circuit, an MOS element, a reverse protection circuit and a temperature control circuit. By sensing the running temperature of the motor by the temperature sensor and feeding it back to the motor and offering proper current as tied in with a current limiting resistor, thermal shutdown will not happen.

Abstract: A voltage detection section and current detection section detect a voltage and current supplied to a motor, and the detected voltage and current are supplied to a position detection section. An angular speed output from the position detection section is supplied to a differentiator to output an angular acceleration. A fundamental wave component extraction section extracts a fundamental wave component of the angular acceleration, and the extracted fundamental wave component is supplied to an amplitude adjustment section. The output of the amplitude adjustment section is subtracted from the average current command by a subtraction section. This subtraction result, current detection value, and the rotor position from the position detection section are supplied to a current control section to carry out the current control operation so as to obtain a current command.

Abstract: A hybrid electric vehicle having an energy generation system, an energy storage system and at least one, and preferable two or more, traction drive units includes a controller for controlling operation of vehicle systems. The controller may adaptively control traction by one or more traction drive units to better propel the vehicle. The controller may, for example, prevent unnecessary wheel slip, allow a traction profile to match a desired profile, and may be used to assist in turning of the vehicle. A method of adaptive control is also provided.

Abstract: A motor system includes four brushes electrically connected to a rotor. A stator includes two magnetic poles. A circuit selectively rotates the rotor at a first speed by applying a first voltage to a first of the brushes and a second voltage to a second of the brushes. The circuit selectively rotates the rotor at a second speed by applying the first voltage to the first brush or the second brush, and applying the second voltage to a third of the brushes and/or a fourth of the brushes.

Abstract: A method and an apparatus for precisely controlling the rotation speed of a spindle motor in an optical system according to a given condition are provided. The method involves counting in response to a clock signal widths of first and second logic states of an input signal, which varies with rotation speed of the spindle motor, when an operation control command is issued, comparing a predetermined reference value with a count value for one check cycle, and outputting the comparison result; and controlling the constant linear velocity of the spindle motor in response to the comparison result.

Abstract: A circuit (10) for a fan motor comprises a driver circuit (12) having an FG terminal which is able to output a first signal carrying speed information of the fan motor, a photo coupler (142) connected to the FG terminal to receive the first signal, the first signal being convertible by the photo coupler to a second signal carrying the same speed information, and a speed detection circuit (16) connected to the photo coupler to recognize the speed information by detecting the second signal.

Abstract: The present invention provides a system for controlling the speed of a motor by altering the magnetic field of the motor. The system includes field modification module, and a motor having field windings and a rotor. The field windings are configured to receive a driving signal that generates a magnetic field causing a rotation of the rotor. The field modification module is proximate the motor and alters the magnetic field in response to an input signal thereby controlling the speed and torque of the rotor.

Abstract: A method of dynamically damping an electric motor (12) that is controlled by an H-bridge driver (16) by interdigitating power pulses with braking pulses by switching from a power switch mode to a shorting circuit mode with switches (22 and 26) closed that brakes the electric motor.

Abstract: A fan motor speed control circuit includes a driving circuit, a voltage division circuit, and a speed modulator. The voltage division circuit has a first transistor and a plurality of resistors and is connected between a voltage source and the driving circuit. The speed modulator has a second transistor and a plurality of parallel resistors and is connected between the voltage division circuit and the driving circuit. The current of the fan motor speed control circuit flows through a first path under a first input voltage generated from the voltage source and through a second path under a second input voltage larger than the first one; the parallel resistors are in the second path such that the current value passing through the driving circuit varies according to the resulting resistance value of the parallel resistors.

Abstract: Method and apparatus for controlling a moving speed of a moving body, wherein at least one transient target speed value in addition to a final target speed value is used to control the moving speed in an accelerating period between a moment of initiation of a movement of the moving body and a moment at which the moving speed should coincide with the final target speed value. The transient target speed is updated at a predetermined timing, or changed to the final target speed value, or from one transient value to another transient value before it is changed to the final target speed value, so that the moving speed is smoothly increased to the final target speed value, without an overshoot beyond the final target speed value.

Abstract: A method for speed control for a motor of a locomotive of a model electric train is presented. A method in accordance with the present invention includes sensing an operating velocity of the motor and the operating current provided to the motor, and then producing a signal corresponding to the operating velocity and a signal corresponding to the operating current. A method in accordance with the present invention further includes providing the operating velocity signal and operating current signal to a controller and establishing a target motor velocity. A method in accordance with the present invention still further includes calculating a target current configured so that the motor reaches the target motor velocity, and then changing the operating current to the target motor current to achieve the target motor velocity.

Abstract: An improved variable speed fan controller for use in devices such as laser printers. The controller automatically adjusts its output signal to fans such that a fan quickly settles into an appropriate operating speed, even if the fan has been newly installed into the equipment. The controller can store values in non-volatile memory, if desired, to keep track of recent changes in the fan's operating parameters and corresponding control signal values. The controller is able to control relatively inexpensive fans that don't necessarily operate at a predictable fan rotating speed under repeatable conditions and control signals, by controlling the fan to an initial or predetermined rotating speed; if the fan isn't running within a suitable range of rotational speeds, then determining whether a fine or coarse adjustment should be made to the fan's rotational speed. The controller makes appropriate adjustments until the fan's rotational speed is within acceptable operating tolerances.

Abstract: In a motor rotation rate detecting circuit incorporating a conventional differentiating circuit, raising the upper limit of the differentiating operation frequency of the differentiating circuit to cope with an increased range of the motor rotation rate causes the differentiating circuit to amplify high-frequency noise when the motor is rotating at a low rate. To solve this problem, a motor rotation rate detecting circuit embodying the invention incorporates a differentiating circuit that produces a rotation rate detection signal by differentiating a plurality of alternating signals having different phases that are output according to the rotation position of the motor, and the frequency response of the differentiating operation of the differentiating circuit is switchable according to the voltage of the rotation rate detection signal.

Abstract: A cooling fan includes a fan, a motor coupled to the fan to drive the fan and a microcontroller. The microcontroller is connected to the motor and is capable of detecting a speed of the fan in real time and maintaining a constant speed of the fan regardless of changes in input voltage.

Abstract: A localized system for dissipating heat generated by an electronic component includes a controllable cooling element and a control system for controlling the cooling element. The control system adjusts a speed of operation of the cooling element in response to variations in power consumption of the electronic component.

Abstract: A remotely configurable motor controller system comprises a motor controller and a remote configuration device. The motor controller includes solid state switches for connection between an AC line and motor terminals for controlling application of AC power to the motor and a control circuit for controlling operation of the solid state switches. The control circuit comprises a programmed processor for commanding operation of the solid state switches and a memory connected to the programmed processor storing configuration information relating to operation of the solid state switches. A wireless communication interface is operatively connected to the programmed processor.

Abstract: The present invention includes a method for managing processor execution time in a motor controller. The method includes receiving motor speed data, comparing the received motor speed data to predetermined motor speed ranges, determining a motor speed range based on the comparison, and modulating an inverter switching frequency of the motor controller processor based on the motor speed range. The step of receiving motor speed data may include receiving machine terminal information, processing the received machine terminal information utilizing a sensorless control algorithm, and determining motor speed data based on the processed information. The step of modulating the inverter switching frequency may include determining a modified inverter switching frequency value based on the determined motor speed range and providing the modified inverter switching frequency value to a processor control algorithm.

Abstract: A disk drive is disclosed wherein a BEMF speed error is measured during a BEMF spindle speed control mode, and a spindle control current is updated in response to the BEMF speed error to drive the disk at an operating speed. A reference time period (RTP) is calibrated, and a sinusoidal error in a wedge time period (WTP) due to eccentricity in the disk rotating is estimated to generate an eccentricity compensation value. After switching to a wedge spindle speed control mode, an actual WTP is detected and a wedge speed error is generated in response to the RTP, the detected actual WTP, and the eccentricity compensation value. The disk is then maintained at the operating speed by updating the spindle control current in response to the wedge speed error.

Abstract: An actuator is provided having an electric motor that generates a back emf. The actuator also includes a control system for controlling the speed of the electric motor. The control system includes a controller and circuitry for allowing the controller to sample the back emf of the motor. The controller uses the sampled back emf as feedback representative of motor speed for use in controlling the speed of the motor.

Abstract: A speed adjuster is provided in a belt-disc sander for controlling the rotating speed of a motor of the belt-disc sander. A speed adjust knob is disposed outside the belt-disc sander. The speed adjuster has a control circuit, a current sensor, a drive circuit, and a converter. The current sensor detects the motor current and feeds back to the control circuit, which controls the frequency variation of a SPWM signal of the drive circuit in response to the input of the speed adjust knob. The converter transforms the square wave voltage into an AC voltage for driving the motor. The desired rotating speed can be adjusted through the speed adjust knob. The control circuit will compare the present rotating speed of the motor with the set rotating speed to determine whether the present rotating speed conforms to the set one for correcting the rotating speed of the motor.

Abstract: When digitizing a voltage, a capacitor is charged, through an impedance, to a voltage value (Um) dependent on the voltage to be digitized. The limits of that one of a plurality of voltage ranges in which said voltage value (Um) lies, are ascertained, and the two limits of that voltage range are defined as a first limit and second limit; the voltage at the capacitor is modified to the first limit by a charge modification circuit containing an impedance, and a first time interval needed therefor is identified; the voltage at the capacitor is modified to the second limit; the voltage at the capacitor is modified from the second to the first limit via the charge modification circuit. A seond time interval needed therefor is identified. Based on values of the first time interval and second time interval, a digital value is calculated, which serves as an indication of how much the voltage value (Um) at the capacitor differs from one of said two limits.

Abstract: An apparatus, method and program product position a powered examination chair at a constant, desired speed despite fluctuations line voltage. A power signal supplied to an actuating motor of the chair is apportioned according to the line voltage supplied to the chair. The desired speed may be customized by a user in the field.

Abstract: Kinetic energy of a rotor is substantially prevented from exceeding a predetermined amount of kinetic energy by determining a first kinetic energy of the rotor spinning at a first rotational velocity and determining whether the first kinetic energy exceeds the predetermined amount of kinetic energy. In addition, torque being applied to the rotor is modulated in response to the first kinetic energy exceeding the predetermined amount of kinetic energy. In this manner, the rotor is spun at a relatively slower rotational velocity than the first rotational velocity.