Abstract: An electric motor protection system for protecting an electric motor of a household appliance includes a temperature sensor for sensing a temperature of the electric motor, a motor speed sensor for sensing a speed of the electric motor, a current sensing circuit for sensing an electric current supplied to the electric motor, a power control device for controlling the electrical power supplied to the electric motor, and a signal processing unit electrically connected to the temperature sensor, the motor speed sensor, the current sensing circuit, and the power control device. The signal processing unit is configured to make calculations and judgments based on the measurements of the temperature sensor, the motor speed sensor and the current sensing circuit, and a plurality of predetermined values, and to control the power control device accordingly so as to protect the motor from overheating, being overloaded, or driven by excessive current.

Abstract: Methods, system and apparatus are provided for sensorless control of a vector controlled motor drive system that includes an electric motor used to drive an auxiliary oil pump.

Abstract: In a steering control unit, a U-phase feed line branches into paired branch feed lines, phase-open MOSFETs are provided in middle portions of the branch feed lines, phase-open MOSFETs are provided in middle portions of a V-phase feed line and a W-phase feed line, and the phase-open MOSFETs are arranged in such a manner that parasitic diodes are in the same orientation with respect to a motor. When an abnormality occurs, all the phase-open MOSFETs are turned off. Then, a closed circuit, which includes phase coils and through which electric currents flow, is no longer present.

Abstract: The present invention discloses a controller and a method for adaptively adjusting motor driving current waveforms. According to the present invention, the controller receives multiple different control parameters which may be determined according to the characteristics of a fan to be controlled, and adjusts the delayed ON time and advanced OFF time of a PWM driving signal based on the control parameters and the present rotation speed of the fan motor, so that the fan operates under an optimum driving current waveform.

Abstract: When an electrification failure occurs in any of the phase of a motor, a control device of an electric power steering device executes current control for generating, in each of two electrification phases other than a phase with the electrification failure, a phase current that changes in the form of a secant curve or a cosecant curve based on an asymptotic line, which is a predetermined rotational angle corresponding to the phase with the electrification failure, to thereby continuously output a motor control signal. The control device of the electric power steering device executes current restriction for restricting the phase current within a predetermined range. The control device of the electric power steering device further executes control for accelerating rotation of the motor during two phase drive, in order to prevent the occurrence of a stuck steering wheel during low-speed steering, which is caused as a result of the execution of the current restriction.

Abstract: The present invention relates to an apparatus and method for determining the speed of a motor, generator or alternator, more particularly for determining the speed of an alternating current (AC) induction motor. The invention overcomes problems associated with previous devices by providing a speed monitoring device that is readily retrofitted to an existing motor an comprises: a means for superimposing a test signal onto an input voltage, which voltage in use is applied to at least one winding of the stator of a motor (the test signal is at a frequency substantially equal to the rotor frequency); a means for varying the frequency of the test signal so that it varies from a minimum frequency to a maximum frequency; and a current monitor for monitoring a resultant current, in said at least one stator winding; and deriving from said resultant current a signal indicative of the rotor frequency.

Abstract: An electric power steering system includes a multi-phase electric motor, an inverter connected to the rotary electric machine and an electronic control apparatus. One phase of the motor is pulled up by a resistor. The electronic control apparatus detects disconnection abnormality between the motor and the inverter by checking phase voltages of the inverter by stopping the inverter operation. If disconnection is detected, current is supplied to the remaining normal two phases. The electronic control apparatus detects short-circuit abnormality by checking an electric angle (rotation angle) of the motor.

Abstract: An inverter control apparatus includes: a state estimator that calculates an estimated current vector and an estimated magnetic flux vector from a motor command voltage vector, a detected current vector, and a motor parameter; a correction voltage calculator that calculates a correction voltage vector on the basis of a current error between the detected current vector and the estimated current vector; and a correction voltage unit that adds the correction voltage vector to the motor command voltage vector.

Abstract: An alternating-current motor control apparatus includes a stator frequency computing unit configured to compute a stator frequency of a motor magnetic flux; a torque error computing unit configured to compute a torque error by using the motor magnetic flux, an estimated current, and a motor current; and a speed estimator configured to estimate a speed of the alternating-current motor by using the stator frequency and the torque error. The speed estimator includes a proportional controller configured to reduce the torque error to zero, and an adaptive filter configured to eliminate a high-frequency component of the torque error.

Abstract: Systems, methods, and devices are disclosed, including an induction-motor controller that has a motor controller configured to receive alternating current (AC) power with a voltage that varies generally sinusoidally and transmit the AC power during a conduction angle of a cycle of the AC power. In some embodiments, the conduction angle varies generally sinusoidally at a lower frequency than the AC power, and the motor controller may be configured to not transmit the AC power outside of the conduction angle.

Abstract: An open-loop and/or closed-loop control device for operating an asynchronous machine which is fed by a 3-phase power converter. The open-loop and/or closed-loop control structure has a stator flux controller and a pulse pattern generator for generating pulse signals based on mean values. An output of the stator flux controller is connected to an input of the pulse pattern generator, with the result that the pulse pattern generator can generate the pulse signals as a function of a manipulated variable which is generated by the stator flux controller. The stator flux controller is configured so as to generate the manipulated variable as a function of a desired value of the stator flux of the asynchronous machine and as a function of a desired value of the torque of the asynchronous machine. The stator flux controller has a dead-beat control response.

Abstract: A motor control device includes: a motor-current detection unit; a rotational-angular-speed calculation unit for calculating a rotational angular speed of a motor; a rotational-angle-change-amount calculation unit for multiplying the rotational angular speed by a predetermined time so as to calculate a motor-rotational-angle change amount within a predetermined time; a basic-drive-value calculation unit for calculating a basic drive value for driving the motor; a correction-value calculation unit for calculating a correction value for correcting the basic drive value based on the motor current and the motor-rotational-angle change amount; a correction unit for evaluating the motor drive value by correcting the basic drive value by the correction value; and a drive unit for driving the motor by using the motor drive value evaluated by the correction unit.

Abstract: A control console to remotely control medical equipment is disclosed having a base with an ergonomically adjustable pedal system. The base further has an opening to receive the pedal system. The pedal system includes a moveable pedal tray with a pedal base. The tray includes a first left pedal assembly and a first right pedal assembly, and an upper tier having a second left pedal assembly and a second right pedal assembly respectively in alignment with and elevated above the first left pedal assembly and the first right pedal assembly. Rollers are rotatable coupled to the moveable pedal tray to allow it roll over a floor. A drive assembly is coupled between the moveable pedal tray and the base. The drive assembly applies a force to the to roll the moveable pedal tray over the floor within the opening of the base.

Abstract: A motor control apparatus and a motor control method determine whether the motor is in a back-pressure area so as to provide different rotation-speed control signals. When the fan is in the low duty cycle, a first circuit loop is switched on, so that the fan has more accurate rotation speed. When the fan is in the high duty cycle, a second circuit loop is switched on, so that the rotation speed of fan does not be limited to a constant rotation-speed as the fan enters the back-pressure area. Thus, the fan has larger airflow quantity and higher airflow pressure.

Abstract: A system for controlling the fan speed is described. Specifically, one embodiment of the present invention set forth a computing system, which includes a first processing unit including a first sensor, wherein the first processing unit is configured to generate a first pulse-width modulation signal, and a first transmission line further including a first direct current voltage converter configured to convert the first pulse-width modulation signal to a first direct current voltage and a first diode coupled to the first direct current voltage converter, wherein the first diode determines whether the first direct current voltage passes through the first diode. The computing system further includes an amplifier coupled to the first diode, wherein the amplifier is configured to amplify a selected direct current voltage to drive a fan.

Abstract: A method and apparatus for determining speed of a stepper motor. In one embodiment of the method, a first terminal of a first coil of the stepper motor is coupled to an input of a multibit digital-to-analog (A/D) convertor. The stepper motor's a rotor is rotated about an axis while the first terminal is coupled to the multibit A/D convertor. An analog signal is induced at the first terminal generating while the rotor is rotating about the axis. The multibit A/D convertor receives the analog signal induced at the first terminal. The multibit A/D convertor generates a plurality of multibit digital signals in response to receiving the analog signal. The multibit digital signals can be processed to determine the rotational speed at which the rotor was rotating when the A/D convertor generated the plurality of multibit digital signals.

Abstract: A fan controlling circuit for detecting rotational speed of a fan, includes a comparison circuit and a controlling chipset. The comparison circuit receives a rotational speed signal from the fan at one input terminal, a reference voltage at another input terminal, and outputs a filtered rotational speed signal at an output terminal. The controlling chipset receives the filtered rotational speed signal, and outputs control signals to control the rotational speed of the fan.

Abstract: A fan motor speed control circuit includes: a driving circuit configured to drive a fan motor so as to run at a rotation speed corresponding to a drive signal; a comparison circuit configured to output a comparison signal for matching a rotation speed of the fan motor with a target rotation speed, based on a reference signal corresponding to the target rotation speed of the fan motor and a speed signal corresponding to the rotation speed of the fan motor; and a selection circuit configured to output to the driving circuit the drive signal corresponding to one signal out of the reference signal and the comparison signal, the one signal being a signal by which the fan motor is driven at a higher rotation speed.

Abstract: A controller controls the rotational speed of an induction motor, thereby controlling a spindle connected to the induction motor. Although an encoder for detecting the position of the spindle is mounted on the spindle, a speed detector is not attached to the induction motor. The speed of the induction motor is estimated from a spindle speed obtained by the encoder, and an excitation frequency command for the induction motor is determined based on the estimated speed.

Abstract: The controller controls a spindle connected to an induction motor via a belt by controlling the rotational velocity of the induction motor. The spindle has an encoder attached thereto for detecting the position of the spindle, but the induction motor does not have a velocity detector attached thereto. The velocity of the induction motor is estimated from the spindle velocity obtained from output of the encoder, and slip of the belt is detected based on the estimated velocity of the induction motor. When occurrence of slip of the belt is detected, the estimated velocity of the induction motor will not be used for the control of the induction motor.

Abstract: A control controls starting of an AC rotary machine by calculating a resistance drop component, corresponding to a resistance drop of the AC rotary machine, based on a detection current, and adjusts angular frequency of an AC output voltage based on subtracting the resistance drop component from a voltage command, and, simultaneously, adjusting amplitude of the AC output voltage so that amplitude of an AC phase current may change in conformity with a predetermined function.

Abstract: The present invention provides a motor drive apparatus which improves a trade-off relation between a stable position detection and noise at its driving. A sensorless drive operation circuit calculates by operation a zero cross point (point p) of a voltage of a position detection phase at the next interval, using time information measured based on an output signal from a comparison circuit at the previous interval and the present interval. After the point p has been calculated, points a and b are detected by interrupting a predetermined time drive current.

Abstract: Embodiments of systems and methods for powering a load are provided. In one embodiment, a method may include providing a power converter comprising electrical circuitry comprising at least a first leg and a second leg, supplying an input power signal to the power converter, supplying at least a first gating control signal to the first leg, supplying at least a second gating control signal to the second leg, and outputting at least one output power signal to the load responsive at least in part to the first and the second gating control signals supplied. According to this example embodiment, the first gating signal and the second gating signal may each comprise a waveform comprising a notch, and the second gating control signal may be phase shifted relative to the first gating control signal.

Abstract: A method and apparatus are provided for operation of a three-phase rotating electrical machine which has at least two stator winding sets and each stator winding set has three phase windings connected in star, and the star circuits of the stator winding sets have a phase shift of 30 degrees electrical with respect to one another, and an associated converting unit is respectively provided for each stator winding set, in which method the respective stator winding set is fed by the associated converter unit, and a respectively associated regulation device is provided for each converter unit, and each converter unit is driven by means of a drive signal from the associated regulation device independently of regulation devices of the respective other converter units.

Abstract: A controller for an AC rotary machine, by which a stable rotation angular-frequency estimate (AFE) value can be obtained even in an extremely low speed region of the AC rotary machine is disclosed, and consequently stable control can be performed. The controller includes an AFE outputter that outputs an AFE value based on an angular-frequency calculated value including a rotation AFE value. The AFE outputter includes a lower-limit constant-value (LLCV) outputter that outputs a LLCV, a comparator that compares the angular-frequency calculated value to the LLCV, and a switcher that performs a switching operation according to the comparator. The switcher outputs the angular-frequency calculation value as the AFE value when the angular-frequency calculation value is larger than the LLCV, and outputs the LLCV as the AFE value when the angular-frequency calculation value is equal to or less than the LLCV.

Abstract: A motor speed control circuit includes: a voltage generating circuit configured to change either a reference voltage corresponding to a target rotation speed of a motor or a speed voltage corresponding to a rotation speed of the motor, according to a temperature, and output the reference voltage and the speed voltage, either one of which is changed; a comparison circuit configured to compare the speed voltage output from the voltage generating circuit with the reference voltage output from the voltage generating circuit; and a driving circuit configured to drive the motor so as to match a level of the speed voltage to a level of the reference voltage, based on a comparison result from the comparison circuit.

Abstract: A motor control device has: a motor current detecting portion for detecting, based on a current flowing between an inverter and a direct-current power supply, a motor current flowing through a three phase motor; a specified voltage value producing portion for producing a specified voltage value based on the motor current; a specified voltage value holding portion for holding an earlier specified voltage value outputted from the specified voltage value producing portion; and a specific period setting portion for setting a specific period based on a voltage difference between two of U-phase, V-phase, and W-phase voltages. Outside the specific period, the motor is controlled based on the specified voltage value outputted from the specified voltage value producing portion, and, within the specific period, the motor is controlled based on the specified voltage value held by the specified voltage value holding portion.

Abstract: In a system for controlling rotation of a rotor of a multiphase rotary electric machine in relation to a stator thereof, a superimposing unit superimposes a first frequency signal on the input signal to the multiphase rotary electric machine. The first frequency signal has a first phase and a first period, and the first period is different from a period of rotation of the rotor. An amplitude detector detects an amplitude of a second frequency signal. The second frequency signal is actually propagated in the multiphase rotary electric machine with a second phase based on the superimposed first frequency signal. A rotation angle determiner determines a rotation angle of the rotor so as to eliminate a difference between the detected amplitude of the second frequency signal and a predetermined target amplitude thereof.

Abstract: A device of a motor with a rotation control means that decreases the fluctuation of its rotation period. The control is carried out based on the amplitude and the phase generated by amplitude-and-phase generating devices, detecting passage time of detected portions (13) in different zones. And a color image forming apparatus of tandem type with such motors.

Abstract: A method for driving a power bridge (1) which is used for controlling a multiphase electric load (3), is connectable to said electric load (3) through several arms and is drivable by switching functions determining control vectors for controlling the load, wherein said control vectors are subdivided into the free wheel control vectors and active control vectors. The inventive method is characterized in that it comprises the use of a switching function production method which produced a reduced number of switching function combinations corresponding to the free wheel control vectors for producing a sequence of the control vectors.

Abstract: A method for determining rotor position comprising sending a signal to a stator, receiving a first signal indicative of a first estimated stator inductance, and receiving a second signal indicative of a second estimated stator inductance. The method further includes, calculating a first rotor position angle using a function including the first estimated stator inductance and the second estimated stator inductance.

Abstract: A driving velocity of a motor is detected by processing a position information signal output from a sensor in accordance with a driving position of a motor. The signal processing device includes a position information signal processor (410) that processes the position information signal and calculates driving velocity information of the motor, and an internal position information generator (460) that reflects a latest driving velocity information (?n) calculated by the position information signal processor (410) and generates a latest presumed position of the motor as internal position information. An amplitude correcting unit (465) detects the amplitude of the position information signal from the sensor and corrects the amplitude of the internal position information signal based on the detected amplitude.

Abstract: A slip frequency is estimated from a current instruction or detected currents in an induction motor. Acceleration impossibility in an induction motor drive unit is determined, when the slip frequency exceeds the maximum torque generating slip frequency for the predetermined interval or the time integrating result exceeds a predetermined value; when the q-axis magnetic flux exceeds the maximum torque generating q-axis magnetic flux or exceeds for a predetermined interval; when the estimated rotational speed is under a predetermined value; when the rotational speed variation rate is negative; and when the rotational speed instruction value or the estimated rotational speed is equal to or smaller than a predetermined value. An induction motor drive system and an elevating system including the induction motor drive unit are also disclosed.

Abstract: A method of controlling a motor to cause it to execute a move toward a target position including calculating a deceleration position, wherein when the deceleration position is reached, the motor will be caused to execute a deceleration in a manner that will result in the motor stopping short of the target position, and determining whether the requested move is a first move type after the motor has reached the deceleration position and the deceleration is complete. If the requested move is a first move type, the method includes causing the motor to move toward the target position at a first velocity, and if the requested move is a second move type, the method includes causing the DC motor to move toward the requested target position at a second velocity, wherein the second velocity is greater than the first velocity. Settling time is also varied depending on move type.

Abstract: A clothes dryer has a thermal insulation pad placed in a confined space in the dryer cabinet between the blower fan housing and the dryer cabinet side wall closest to the blower fan housing. The thermal insulation pad is press fit into the space so as to take up much of the volume of the confined space preventing the accumulation of dust or lint over time in the confined space while also preventing the flow of oxygen to the confined space. Accordingly, the thermal insulation pad reduces the risk of a fire starting in the confined area of the dryer cabinet between the blower wheel housing and the adjacent side wall of the cabinet. A thermal insulation pad also acts as sound insulation.

Abstract: A control system and method of massage machine for acting massage therapy on human body includes a common drive motor for driving multiple massage heads, multiple routine keys for setting motor routines and the rotation direction of the drive motor via a multiple sets of motor switches, a timer, and a Single Chip Microcomputer controller for controlling. In operation, a user could not only set operation mode or routine via the routine keys and then activate massage procedure, but also could change the operation mode or routine of the massage machine by reselecting the routine keys at any time.

Abstract: A method for driving a power bridge (1) which is used for controlling a multiphase electric load (3), connectable to said electric load (3) via several arms and drivable by switching functions which determine free wheel controlling vectors and are active for controlling the load. The inventive method consists in selecting a first switching function production method which produces a reduced number of combinations of switching functions corresponding to the free wheel control vectors or a second switching function production method which produces combinations of switching functions corresponding only to the active control vectors, wherein said method are defined according to a given reference voltage vector and in applying said selected for producing a sequence of control vectors from the produced combinations of switching functions.

Abstract: Systems, apparatus, and methods for operating inductors in a Z-source inverter in a continuous current mode are provided. One system includes an AC motor, a Z-source inverter, and a processor. The inverter is configured to provide current and reactive power to the AC motor. The processor is configured to monitor the current and instruct the inverter to provide a greater amount of reactive power to the AC motor if the current is below/equal to a threshold amount. An apparatus includes means for determining if current produced by the inverter is below/equal to a threshold amount, and means for altering voltage commands supplied to the inverter so that an AC motor is induced to draw additional reactive power. One method includes determining if a plurality of inductors are providing a threshold current amount, and inducing a motor to draw more reactive power if the current is below/equal to the threshold amount.

Abstract: A controller of an electric motor for improving operation efficiency in performing electric conducting control of the electric motor of an axial air-gap type is provided.

Abstract: A method is described for operating an electric motor. The electric motor has at least two phases and a rotor. In the method, a current angular position (phipos) of the rotor is ascertained and, as a function of that, in at least one of the two phases, a potential is applied in such a way that a desired angular position (phiposreq) is achieved. From the current angular position (phipos) and the desired angular position (phiposreq) a setpoint angular velocity (dphides) is ascertained, which is used for influencing the potential.

Abstract: A heat exchange cooler capable of eliminating continuous radiation of high-frequency noise waves and reducing the man hour for the installation work, and a power circuit driving device used for it are provided. A commercial power transformer (311), which transforms commercial AC power (307) supplied from a heat generating element storing box to a specified range of voltage, is provided. Moreover, first relay (210) and second relay (212) are used for automatically switching a plurality of taps disposed at the coil of commercial power transformer (311) which keeps a wide range of commercial AC voltage from 200V to 250V in nominal voltage within a specified range of output voltage.

Abstract: A microcomputer includes a calculating section calculating a d-axis electric current command value and a q-axis electric current command value and a signal generating section. The signal generating section generates a motor control signal through feedback control in a d-q coordinate system based on the d-axis electric current command value and the q-axis electric current command value. The microcomputer also has an anomaly determining section, which detects an anomaly if a failure of electric current flow has occurred in any one of phases of a motor. If the anomaly is detected, the microcomputer produces a motor control signal instructing to use, as electric current flowing phases, two phases other than the phase with the failed electric current flow.

Abstract: A motor controller system comprises solid state switches for connection between a single phase to three phase static converter and motor terminals for controlling application of three phase power to the motor. Sensors sense power from the static converter. A control is connected to the sensors and the solid state switches for controlling operation of the solid state switches to run the motor. The controller includes a three phase detection scheme for preventing operation of the solid state switches in the absence of desired three phase power from the static converter. A motor start scheme disables the three phase detection scheme for a select time after a motor run signal.

Abstract: A method for controlling a motor current supplied to an electric motor by using an inverter device is provided. The inverter device includes an inverter circuit and a capacitor connected to an input of the inverter circuit. The method includes controlling the inverter circuit in such a manner as to supply an alternating electric current to the electric motor after the temperature of the capacitor reaches a temperature at which a maximum acceptable motor current value becomes greater than or equal to a value at which the torque necessary for starting the electric motor is produced.

Abstract: A system and method are provided for reducing the energy consumed by a pump jack electric motor by reducing the supply voltage to the motor when the motor would be generating energy in open loop mode. By substantially eliminating the energy generation mode, the braking action of the utility grid in limiting the acceleration of the motor and system that would otherwise occur is substantially removed. The motor and system will speed up, allowing the natural kinetic energy of the cyclic motion to perform part of the pumping action. A closed loop controller in electrical connection with the motor computes the necessary information from the observed phase angle between the voltage and current supplied to the motor. By reducing the supply voltage to the motor, the observed phase angle may be reduced to a target phase angle value.

Abstract: Systems and/or methods that facilitate efficiently controlling speed of an induction motor are presented. An optimized control component controls respective switching of an auxiliary switch component associated with an auxiliary winding of the motor, a main switch component associated with a main winding of the motor, and a capacitance adjuster switch component that facilitates adjusting the amount of capacitance associated with the auxiliary winding. The timing of switching on the auxiliary switch component and main switch component can be controlled such that there can be a time difference between the respective switching on of the auxiliary switch component and main switch component to produce additional phase shift to facilitate improving motor efficiency. The capacitance adjuster switch component can be switched on when motor speed is below a predetermined low speed threshold to facilitate increasing the amount of capacitance associated with the auxiliary winding to improve motor efficiency.

Abstract: A zero-current, synchronous switching waveform is provided for a three-phase, wye-connected H-Bridge to power an electric motor. The switching waveform includes two notches per cycle on the switching waveform provided to each of the semiconductor switches to minimize total harmonic distortion and switching loss. Positioning of the notch with respect to the zero-current crossing is optimized to reduce switching loss and minimize total harmonic distortion.

Abstract: A temperature estimation controller and methods are provided for controlling a torque command to prevent overheating of one or more of a plurality of phases of a permanent magnet motor. The temperature estimation controller includes a low speed temperature estimation module, a transition module and a temperature dependent torque command derater block. The low speed temperature estimation module determines a stator temperature of each of a plurality of phases of the permanent magnet motor in response to first thermal impedances measured for each of the plurality of phases with respect to a thermal neutral. The transition module is coupled to the low speed temperature estimation module and outputs the stator temperature of each of a plurality of phases of the permanent magnet motor as determined by the low speed temperature estimation module when a detected speed of the permanent magnet motor is less than a first predetermined speed.

Abstract: In an electric vehicle drive apparatus having an electric motor and a motor drive device, the electric motor having a stator, a rotor and a moving mechanism capable of changing a relative distance between the stator and the rotor to vary an effective magnetic flux of the motor, the motor drive device compares a regenerative current with a target current during a regenerative control of the motor, and when it is found that the regenerative current is larger than the target current, the distance between the stator and the rotor is increased to reduce the effective magnetic flux.

Abstract: A power tool may include an electronically commutated motor such as, for example, a brushless DC permanent magnet motor with a rotor having internally mounted magnets and/or cavities filled with air or other non-magnetic materials. A control system may be used to control the motor in a manner that implements field weakening when the speed of the motor increases beyond its rated motor speed, or when the torque demands on the motor continue to increase after the maximum power output of the motor is reached. The field weakening may offset the growing back EMF and may enable a constant power and constant efficiency to be achieved by the motor over a wide speed range, rather than at just a single predetermined operating speed. Pulse width modulation control of the motor may be used up until the motor reaches its maximum power output.