Abstract: A motor control method includes the following steps: receiving a frequency command and an excitation current setting value as a motor speed command; running a magnetic flux calculation program to generate a magnetic flux voltage command; generating a synchronous coordinate voltage command, and providing a three-phase current to a sensorless motor; calculating a synchronous coordinate feedback current based on the three-phase current, and calculating an effective current value of three-phase current; calculating a reactive power feedback value based on synchronous coordinate voltage command and the synchronous coordinate feedback current; running a steady state calculation program to calculate a reactive power command based on frequency command and the effective current value; calculating a reactive power error value between the reactive power command and the reactive power feedback value; and adding magnetic flux voltage command and reactive power error value to adjust synchronous coordinate voltage command a

Abstract: An electric device is provided which can reduce risk of malfunction. This electric device is provided with a motor (31), an inverter circuit (30) which has switching elements (S1-S6) and which drives the motor (31), and a charge pump circuit (22) which generates the drive voltage of the switching elements (S1-S6). A discharge circuit (a discharge resistor R and a capacitor C1) is provided between a power line to which a drive voltage (VM) of the motor (31) is supplied and an output terminal (a VGT terminal) of the charge pump circuit (22). Energy of the surge voltage (Vs) generated in a parasitic inductance (Ls) when the switching elements (S4-S6) are turned off is absorbed by the discharge circuit (the discharge resistor R and the capacitor C1).

Abstract: A motor drive control device capable of determining a drive state of a motor is provided. The motor drive control device includes a plurality of motor drive circuits performing, based on drive control signals (Sca1 and Sca2) for controlling the number of rotations of a motor, control of energization of the motor and outputting FG signals (fg1 and fg2) having a cycle corresponding to the actual number of rotations of the motor, a composite signal generation circuit receiving an input of each of the FG signals output from the motor drive circuits and generating a composite signal by combining input signals, and a drive control circuit generating, based on a speed command signal indicating a target number of rotations of the motor, the drive control signals and outputting the drive control signals to each of the motor drive circuits. The FG signals output from the motor drive circuits have a phase difference from each other.

Abstract: In an embodiment, an electronic circuit includes: a controller configured to produce a pulse-width-modulated (PWM) signal to control a first current of an electrical load; a redundant current measurement circuit configured to measure the first current and provide first and second current measurement signal; a monitor circuit coupled to the redundant current measurement circuit, the monitor circuit configured to assert a current monitor signal in response to the first and second current measurement signals being found to be matching with each other, wherein the monitor circuit is configured to: detect an absence of the asserted current monitor signal prior to expiry of a threshold time interval, and in response to detecting the absence of the asserted current monitor signal, force the controller to produce, prior to expiry of the threshold time interval, a first PWM signal pulse having a controlled duty-cycle.

Abstract: A commutation control method, a device for a brushless direct current motor, and a storage medium are described. The method includes performing detection on a position of a rotor in a brushless direct current motor. The detection is further configured to be triggered by commutation of the brushless direct current motor. The method includes determining, for the brushless direct current motor, a first drive scheme corresponding to the detected position of the rotor, the first drive scheme indicates a manner in which a three-phase full-bridge circuit of the brushless direct current motor operates; updating a pulse width modulation (PWM) drive signal, the updating is performed on the basis of the first drive scheme; and using the updated PWM drive signal to control the brushless direct current motor to perform commutation.

Abstract: A synchronous machine includes a stator with stator windings connected with stator terminals to an electrical grid and a rotor with rotor windings rotatable mounted in the stator, wherein a voltage regulator of the synchronous machine is adapted for outputting an excitation signal to adjust a current in the rotor windings for controlling the synchronous machine. A method for determining control parameters for the voltage regulator includes (i) receiving a first time series of values of the excitation signal and a second time series of measurement values of the terminal voltage in the stator terminals, (ii) determining coefficients of a system transfer function of the synchronous machine, and (iii) determining the control parameters for the voltage regulator from the coefficients of the system transfer function.

Abstract: An estimation method for estimating a rotor frequency of a motor during freewheeling, includes: applying a fixed input voltage and one selected from a plurality of stator frequencies to the motor sequentially so as to perform frequency scanning; detecting a stator current value of the motor corresponding to the selected stator frequency; calculating a stator current slope of the stator current values sequentially; defining a target period from a start point where the stator current slope varies from positive to negative to an end point where the stator current slope varies from negative to positive; and determining that a difference between the scanned stator frequency and the rotor frequency is within a preset value, then designating any of the corresponding stator frequencies during the target period as an estimated value of the rotor frequency.

Abstract: The task of the present invention is to provide a driving circuit capable of outputting information useful to design or control of a system to outside. The present invention relates to a driving circuit and a driving method of a stepping motor, and an electronic machine using the driving circuit of a stepping motor. A counter electromotive force detection circuit detects a counter EMF generated in a coil. A revolution count detection circuit acquires the revolution count of the stepping motor. A load angle estimating portion calculates a load angle according to the counter EMF and the revolution count. An interface circuit is configured to be capable of outputting angle information associated with the load angle to outside, or accessing the angle information from the outside.

Abstract: An apparatus can include a fan including a control pin. The fan may receive a pulse width modulated (PWM) signal at the control pin. The fan may further control a speed of the fan based on a duty cycle of the PWM signal when the PWM signal is in a first range and, responsive to the duty cycle of the PWM signal being in a second range, transmit information corresponding to the fan to an external controller.

Abstract: A pulse pattern generation device generating a pulse pattern for controlling switching elements provided in an inverter that operates a motor, the pulse pattern generation device includes a current calculation unit that calculates a current flowing through a coil when a voltage that is applied to the motor during the operation of the motor is virtually applied to the coil of the motor, an effective current calculation unit that calculates an effective current from the current calculated by the current calculation unit, an iron loss estimation unit that estimates an iron loss which originates in a core of the motor, and a pattern generation unit that generates a pulse pattern using an evaluation function including the iron loss estimated by the iron loss estimation unit and the effective current calculated by the effective current calculation unit as evaluation items.

Abstract: A power tool is provided including a brushless motor having a stator defining a plurality of phases and a rotor. A power unit is provided including power switches operable to deliver power to the motor. A primary controller is interfaced with the power unit to output drive signals to drive the phases of the motor over a series of sectors of the rotor rotation. The primary controller measures a back-electromotive force voltage of the motor and transitions motor commutation from the present sector to the next sector based in relation to the back-EMF voltage. A second controller is provided to receive at least one of the drive signals, calculate a speed and/or direction of rotation of the motor from the drive signals, and take corrective action to cut off supply of power to the motor if it detects an overspeed condition or incorrect direction of rotation.

Abstract: A vehicle includes a traction battery, an inverter, and a controller. The inverter includes a plurality of pairs of switches. Each of the pairs includes an upper switch that is directly electrically connected with a positive terminal of the traction battery and a lower switch that is directly electrically connected with a negative terminal of the traction battery. The controller, responsive to presence of a fault condition and during each of consecutive switching periods, deactivates all of the switches for a predetermined portion of the switching period, activates only the upper switches for another predetermined portion of the switching period, deactivates all of the switches for yet another predetermined portion of the switching period, and activates only the lower switches for still yet another predetermined portion of the switching period.

Abstract: To avoid cost increase, delay of response, time, and performance degradation in driving a power source including a plurality of servo motors and/or a servo motor with a plurality of windings. A slave unit drives a power source including a plurality of servo motors and/or a servo motor with a plurality of windings using a plurality of amplifiers on the basis of a command from a high-order controller.

Abstract: A method of operating a Brushless Direct Current Motor (BLDCM), the BLDCM of the type including: a series of concentric independently activated electromagnetic phase coils interacting with a series of permanent magnets to provide relative movement therebetween, the phase coils having temporal periods of activation time and deactivation time, the method including the steps of: (a) activating at least one of the phase coils for a short period of activation; and (b) measuring the voltage response across the phase coil of the deactivated phase coil during the short period of activation to determine the rotor position.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed to bypass sensed signals in power converters. The disclosed methods, apparatus, systems and articles of manufacture provide an apparatus to bypass sensed signals in power converters, the apparatus comprising: a first single shot circuit to, during runtime of a power converter, generate a clock signal based on an adaptive delay, the adaptive delay based on a count value of a counter; a pulse comparator coupled to an adaptation pulse generator, the pulse comparator to, during runtime of the power converter: compare a first duration of the adaptation pulse to a second duration of a reference pulse; and adjust the count value of the counter; and a ready detector coupled to the pulse comparator, the ready detector to, in response to a trigger event, transmit, during runtime of the power converter, the count value to a second single shot circuit.

Abstract: A motor-drive system may include a rectifier, a metal-oxide varistor (MOV) assembly, and an inverter. The rectifier may generate a direct current (DC) voltage based on a first voltage received from at least one supply voltage line coupled to a voltage source. The MOV assembly may include at least two metal-oxide varistors (MOVs) respectively coupled to the at least one supply voltage lines. The MOV assembly may couple between the voltage source and the rectifier. The motor-drive system may also include a permanently-installed jumper to couple at least one MOV of the at least two MOVs of the MOV assembly to a system ground. The inverter of the motor-drive system may convert the DC voltage to an alternating current (AC) voltage, which may be provided to a load of the motor-drive system.

Abstract: A device, which may be embedded in a power distribution enclosure, enables analysis of the conditions of an electromechanical machine operating on a commonly supplied network with other electromechanical machines. The analysis preferably uses aggregate operating voltage and current signals supplied to or from such machines along with known changes in steady-state conditions of one or more machines to discern the discrete effect of one or more machines to the aggregate electrical signal. Such discrete effect can then be associated with the operating performance of the individual machine. And, since such voltage and current signals are normally readily available at the enclosure, wiring or any other communication means to any sensors on the electromechanical machines or devices are not necessary. The embedded device may optionally receive or transmit information to a computing or monitoring device remote from the enclosure.

Abstract: A UVW-phase inverter control circuit has a control function of generating a UVW-phase inverter control signal. An XYZ-phase inverter control circuit has a control function of generating an XYZ-phase inverter control signal. The control function of the UVW-phase inverter control circuit is stopped during execution of a BIST. A phase conversion unit generates a UVW-phase inverter control signal by phase conversion for the control signal from the XYZ-phase inverter control circuit. During execution of the BIST by the UVW-phase inverter control circuit, a selector outputs the inverter control signal from the phase conversion unit as a UVW-phase inverter control signal, and a selector outputs the inverter control signal from the XYZ-phase inverter control circuit as an XYZ-phase inverter control signal.

Abstract: An electric propulsion system includes a prime mover, a starter-motor generator configured to be driven by the prime mover to generate electric power, and an electric propulsion motor, and an integrated generator-motor controller arranged to control the supply of the electric power to the electric propulsion motor in response to a control signal, wherein the integrated generator-motor controller includes an active rectifier configured in a first mode to feed-forward to the starter-motor generator a power demand parameter associated with the control signal so as to control the power output of the starter-motor generator in order to start the prime mover.

Abstract: A method for determining a direct inductance and a quadrature inductance of an electrical machine is included. The method includes controlling the electrical machine so that a stator generates a first magnetic field rotating at a first rotation frequency to rotationally drive a rotor of the electrical machine, and a second magnetic field that varies periodically at a second frequency for measuring a portion of the phase currents flowing through the stator windings of the electrical machine during controlling of the electrical machine. The method further includes determining an amplitude spectrum of a given electrical quantity determined based on a portion of the phase currents, searching in the amplitude spectrum for a peak present at a frequency that is dependent on the second frequency, determining an amplitude of each peak found, and determining the direct inductance and the quadrature inductance from the amplitudes of two peaks found.

Abstract: A vacuum pump and a motor controller that make a safe transition to a regeneration mode while avoiding an overvoltage are provided. A turbo molecular pump includes a power supply unit that converts alternating-current power to direct-current power and outputs the power, the alternating-current power being obtained from an alternating-current power supply, and the motor controller that controls a motor.

Abstract: A data storage device is disclosed comprising a head actuated over a disk, and a spindle motor configured to rotate the disk. A pulse width modulated (PWM) control signal is generated having a frequency based on a PWM clock, the spindle motor is controlled using the PWM control signal, and a frequency of the PWM clock is swung between a minimum frequency and a maximum frequency at a swing rate.

Abstract: A computer program causes a computer to execute processing of simulating behavior of an electromagnetic component including a coil at each of a plurality of time points based on an analytic model of the electromagnetic component. The processing comprises creating a look-up table storing a flux linkage of the coil, an inductance of the coil and a current in the coil that are obtained by a magnetic field analysis based on the analytic model in association with one another, and simulating behavior of the electromagnetic component by referring to the look-up table using currents in the coil calculated at a previous simulation step and at a step before the previous simulation step.

Abstract: A waveform control unit outputs a signal for driving a brushless DC motor by intermediate value energization to a waveform output unit, and outputs a signal for driving a brushless DC motor by sine wave energization to the waveform output unit when the signal in which the rotation position of the rotation reference is detected is acquired from the element, and the waveform control unit applies voltage corresponding to a sine value of an angle of a winding of one phase of n-phase windings when the brushless DC motor is to be driven by intermediate value energization, and outputs a signal for applying voltage corresponding to a sine value of an angle having similar phase difference as the sine wave energization drive with respect to the angle to the rest of the windings.

Abstract: The present invention is directed to a hair cutting apparatus (600), such as a shaver, which is enabled to detect whether hair is currently being cut in a robust way. Such apparatus has a motor (102) for driving a cutting element. The motor current (106) is evaluated by filtering and amplifying it in such a way that a time derivative of the motor current (106) is processed and other parts of the motor current (106), such as noise and DC-5 parts, are eliminated. An evaluator determines whether the time derivative of the motor current is above a predefined threshold value.

Abstract: A system and computer-implemented method for reducing an angle error in an estimated position of a rotor over various loads on an electric motor or type of electric motor. Electrical parameters of an electric motor are measured, a true rotor position is found, and sensorless gains based on the measured parameters are generated, including determining a sensorless angle. Data is gathered at multiple torque levels for at least one speed of the motor, including for each torque level, trying different inductance values, and determining an inductance value that results in an angle error of zero. The angle error is the difference between the true rotor position and the sensorless angle. The inductance value that results in an angle error of zero for each speed may be saved in an electronic memory and used to better control the motor or other motors of the same type.

Abstract: One object is to reduce a volume occupied by a device disposed in a first space spatially limited to a large degree. An electric actuator diving and controlling device is provided with a drive unit positioned in a first space in a piece of equipment and configured to apply power to an electric actuator and a control unit positioned in a second space in the piece of equipment and configured to transmit, to the drive unit, a power command signal including information related to power to be applied to the electric actuator. The first space having the drive unit positioned therein is limited compared with the second space having the control unit positioned therein.

Abstract: Timepiece movement fitted with an electromagnetic transducer comprising at least one coil and a rotor formed of a central shaft, of two magnetic plates that are mounted on the central shaft and of a plurality of bipolar magnets which are axially polarized and mounted on at least one of the two magnetic plates, said at least one coil penetrating at least partially into a circular space which is defined by the rotor between its two magnetic plates and left free by this rotor. The central shaft comprises a pinion which engages with a wheel of the timepiece movement, this pinion being arranged between the two magnetic plates and said wheel being partially arranged between the two magnetic plates, in an angular sector of the circular space that is left free by the electromagnetic transducer, so as to engage with the pinion. Advantageously, said wheel has a roller that is almost or entirely non-conductive and a non-magnetic staff.

Abstract: An industrial electrical machine includes a stator; a rotor in magnetic communication with the stator; a plurality of windings disposed in the rotor and/or the stator; and an embedded solid state controller. The solid state controller is operative to control the operation of the industrial electrical machine. The solid state controller includes a power semiconductor switching device coupled to the plurality of windings, and includes a communication interface. The power semiconductor switching device is operative to provide switching during operation of the industrial electrical machine, and is operative to turn the electrical machine on and to turn the electrical machine off in response to a control input received by the communication interface.

Abstract: A fan comprising: (a) an impeller, (b) a motor connected to the impeller so that during operation the motor drives the impeller to move a fluid; (c) an instrumentation assembly that includes one or more components for controlling one or more operations of the fan; (d) an interface in communication with the instrumentation assembly; wherein the interface is configured so that one or more programs, one or more signals, or both can be input into the fan after a final assembly of the fan so that the fan can be configured to perform a desired function at the time of installation into a final product, reconfigured for a different purpose than originally programmed, or both.

Abstract: An actuator, a robot arm and a robot are disclosed. The actuator includes: a motor, including a housing, a motor stator and a motor rotor, wherein the motor stator is disposed to the housing, the motor rotor is rotatably connected to the housing, and the motor rotor covers the motor stator; a position encoder, disposed to the motor rotor; a reducer, connected to the motor rotor, and configured to adjust a rotation speed output from the motor rotor; and a motor driver, disposed on the housing, and electrically connected to the motor.

Abstract: An electric working machine includes an inverter and a controller. The controller switches a current conduction pattern via the inverter and performs a PWM control of a conduction current to a brushless motor. The controller includes switching patterns as the current conduction pattern switched for every commutation timing. The switching patterns include different on and off states for different switching elements. The controller sequentially switches a switching pattern synchronously with a period of the PWM control, detects a rotational position of a brushless motor from a magnitude relation between inductances of the brushless motor produced by switching the switching pattern, and sets the commutation timing.

Abstract: A power conversion device includes: a rectifying unit rectifying an AC voltage output from an AC power supply; a booster circuit boosting an output voltage of the rectifying unit; a control unit causing the booster circuit to perform synchronous rectification; and a smoothing capacitor smoothing an output voltage of the booster circuit. The booster circuit is constituted by connecting a plurality of chopper circuits in parallel to each other, the chopper circuits each including an upper arm switching element and a lower arm switching element connected in series to a reactor connected to the rectifying unit, and the control unit generates a drive pulse causing the upper arm switching element to be turned on when a reverse current flows through the upper arm switching element.

Abstract: Systems and methods for computing an average supply current to a motor include a current sensor that is configured to sense a current through the motor. A converter is configured to sample the output of the current sensor at times that are established by a trigger signal and convert the samples into digital current values. A trigger signal generator generates the trigger signal based on one or more pulse width modulated (PWM) motor control signals within a PWM cycle. An average supply current value that indicates the average supply current to the motor is computed by a controller using the digital current values received from the converter.

Abstract: A motor drive device can include: a control circuit configured to adjust each phase current of a three-phase inverter of a motor; where the phase current of the three-phase inverter rises from zero to a first threshold during a first time interval; and where the phase current is controlled to drop gradually from the first threshold to zero during a second time interval in order to increase the second time interval.

Abstract: A motor control system for reducing or eliminating current ripple error during current sampling comprises a motor having a plurality of phase coils, a motor driver circuit having a plurality of switches coupled to the plurality of phase coils to drive current through the phase coils, and a motor controller circuit configured to provide a plurality of output control signals coupled to the plurality of switches. A phase circuit modifies a first output control signal to produce a modified control signal that is out of phase with a second output control signal. A current measuring circuit is included to measure a current through the motor by measuring the current during a first time period when the first output control signal is active and measuring the current during a second time period when the modified control signal is active.

Abstract: A power converting apparatus and a home appliance having the same according to the present invention includes: an input unit including an AC connection unit which receives an alternating current (AC) power from an external and a DC connection unit which receives a direct current (DC) power; a bridge diode unit which always outputs the DC power having a given polarity when DC power is connected to the input unit, and rectifies the AC power received through the input unit when the DC power is connected to the input unit; and a capacitor which is connected to a DC terminal which is an output terminal of the bridge diode unit.

Abstract: A signal conditioning apparatus includes a timing extractor to received one or more stepper motor drive signal and convert each into a corresponding virtual quadrature trigger signal. A resolution scaler is coupled to an output of the timing extractor to scale the virtual quadrature trigger signals to adjust the transition frequency, thereby adjusting the resolution of an image captured by a camera receiving the trigger signals to be different than the print resolution created by the motor drive signals. A quadrature decoder is coupled to the output of the resolution scaler, wherein the quadrature decoder extracts timing and direction information from the virtual quadrature trigger signals received from the resolution scaler.

Abstract: A motor control device includes: a noise reduction unit that sets a PWM count in units of PWM cycles for each PWM cycle in a current control cycle such that a current that flows through a frame ground because of a phase voltage for any one of three phases is canceled out with a current that flows through the frame ground because of a phase voltage for one of the two other phases in each PWM cycle in the current control cycle; and a noise canceling circuit configured to generate a current that is opposite in phase to a current that flows through the frame ground because of a phase voltage for the other of the two other phases in each PWM cycle in the current control cycle.

Abstract: In order to shorten an activation time while realizing stable motor control, a motor control apparatus operable to control a motor is provided. The apparatus controls so as to drive the motor by the forced commutation control in a duration from a start of control of the motor until a first time period elapses, and control so as to drive the motor by the vector control after the first time period has elapsed. In addition, the apparatus controls an execution frequency of a current detection and a rotation speed estimation. The apparatus controls so that a first execution frequency in a second time period after a switch is made from driving by the forced commutation control to driving by the vector control is greater than a second execution frequency in a third time period subsequent to the second time period.

Abstract: A system and method for wirelessly communicating with an HVAC motor or other motor in order to manage the motor with regard to, e.g., identifying a suitable replacement for, programming, monitoring and/or diagnosing, and/or tuning or otherwise reprogramming the motor without physically connecting to the motor. A technician uses a software application on a smartphone, tablet, or other portable device to communicate with the motor controller via a wireless communication device incorporated into the motor assembly. The smartphone may receive relevant information, such as identification, programming, or diagnostic information, and process the information or wirelessly transmit the information to a server for processing. Based on the information, the smartphone may transmit programming instructions to the motor controller via the wireless communication device. Further, the wireless communication device may transmit sensor data associated with the motor to allow for monitoring the motor's performance.

Abstract: A control system for a rotary electric machine includes a controller configured to generate dynamic input current data based upon a dynamic analysis of self flux data, mutual flux data, and saturation scaling factor data. Upon generating a torque request, the controller is configured to determine a desired electrical input based upon the dynamic input current data to generate the desired output torque. The desired electrical input includes a magnitude and duration of an electrical pulse and a desired angular position of the rotor of the rotary electric machine relative to the stator of the machine. The controller determines an angular position of the rotor and generates an operating command to generate the desired electrical input at the desired angular position of the rotor to propel the rotary electric machine and generate the desired output torque. A rotary electric machine and method of operating same are provided.

Abstract: A device and a method for automatically detecting an initial position of a rotor of a motor are provided. The device includes an initial position detector, a lookup table module and a controller. The initial position detector detects input voltages of the motor. The controller compares the input voltages with each other to determine the initial position of the rotor of the motor. The controller obtains a waveform pattern from the lookup table module to construct an activating waveform signal to be outputted to one of steps of the motor that corresponds to the initial position of the rotor to control the motor to run.

Abstract: A multi-phase brushless DC motor driving circuit includes a driving-stage circuit, a PWM generator, a control circuit and a plurality of current detection circuits. The driving-stage circuit includes a plurality of sub-driving circuits each having a high-side transistor and a low-side transistor. The current detection circuits detect the current at a node between the high-side transistor and the low-side transistor of the corresponding sub-driving circuit, and then generate a current detection signal. According to the current detection signals, the control circuit controls the PWM generator to generate a plurality of PWM signals for controlling the conducting and cutting off of the high-side transistor and the low-side transistor of each sub-driving circuit, and to provide a driving current to drive a multi-phase brushless DC motor.

Abstract: An output torque calculation device and a method thereof is provided, and the output torque calculation device includes a first sensor, a second sensor, a rotor, a reducer, a processor, and an elastic device. An input portion of the reducer and an output portion of the reducer are respectively connected to the rotor and an input portion of the elastic device, and an output portion of the elastic device is configured to connect to a load. The output torque calculation method comprises: detecting a first angle of the rotor by the first sensor; detecting a second angle of the output portion of the elastic device by the second sensor; and calculating a torque carried by a final output end of the output torque calculation device by the processor according to the first angle and the second angle.

Abstract: One example device includes a rotor platform that rotates about an axis of rotation. The device also includes a ring magnet mounted to the rotor platform to provide a rotor-platform magnetic field. The device also includes a stator platform that includes a planar mounting surface. The device also includes a plurality of conductive structures disposed along the planar mounting surface. The conductive structures remain within a predetermined distance to the ring magnet in response to rotation of the rotor platform about the axis of rotation. The conductive structures are electrically coupled to define an electrically conductive path that at least partially overlaps the ring magnet. The device also includes circuitry that causes an electrical current to flow through the conductive path. The electrical current generates a stator-platform magnetic field that interacts with the rotor-platform magnetic field such that the rotor platform rotates about the axis of rotation.

Abstract: A motor control device includes: a state monitoring unit that detects a power supply abnormality in which a power is not normally supplied to at least one of a rotation sensor and a motor; an abnormality determination unit that detects an abnormality of the rotation sensor based on an output signal of the rotation sensor; and a decision unit that decides whether to confirm the abnormality of the rotation sensor based on a detection result of the state monitoring unit and a detection result of the abnormality determination unit. When the state monitoring unit detects the power supply abnormality, the decision unit does not decide the abnormality of the rotation sensor even when the abnormality determination unit detects the abnormality of the rotation sensor.

Abstract: To improve identification precision of a motor constant that controls a motor by vector control. A parameter identifier sets an offset voltage of a DC component as a first d-axis target voltage, and detects a d-axis current that flows accordingly as an offset current. The parameter identifier also sets a voltage obtained by superimposing an identification signal of a predetermined AC component on the first d-axis target voltage as a second d-axis target voltage, and detects the d-axis current that flow accordingly. The parameter identifier then identifies the motor constant using a voltage obtained by subtracting the first d-axis target voltage from the second d-axis target voltage and a current obtained by subtracting the offset current from the d-axis current as inputs.

Abstract: A drive system of an embodiment includes an inverter for driving an electric motor; a detector that detects an electric current value output from the inverter; command generators that generate an electric current command value corresponding to an electric current to be supplied to the electric motor and a gate command of the inverter so that the electric current command value matches the electric current value; calculators that calculate an voltage target vector of the inverter and a rotation phase estimation value of the electric motor based on the electric current value and the voltage target vector, in an initial estimation of when activating the inverter. The electric current command value in the initial estimation is a value to supply an electric current for magnetically saturating a rotor of the electric motor, and a dynamic inductance of the electric motor used for calculating the rotation phase estimation value is a value of when the rotor of the electric motor is magnetically saturated.

Abstract: According to one aspect, a method includes obtaining a first signal from a host at an air mover system, the air mover system including an air mover and a tachometer, the tachometer having an associated tachometer signal. The method also includes determining whether the first signal is a request for information associated with the air mover, and providing the information from the air mover system to the host on the associated tachometer signal when it is determined that the first signal is the request for information associated with the air mover.