Abstract: An inverter has a current sensor that senses a low side current before a high side of the inverter is permitted to power up. If an over-current situation is detected on the low side, powering up is prevented in order to avoid damage to the rectifier.

Abstract: The present invention discloses a motor deceleration method which is applied to a motor driving apparatus. The motor driving apparatus includes an energy-storing unit and a controlling unit, and outputs a driving signal to control the motor. The controlling unit controls a driving frequency of the driving signal. The driving deceleration method includes following steps of controlling the driving frequency to zero; increasing the driving frequency in a linear way by using the controlling unit; detecting whether a terminal voltage difference of the energy-storing unit is increased to a preset voltage value, and if yes, adjusting the driving signal to keep the terminal voltage difference at the preset voltage value; and reducing the driving frequency continuously to decelerate the motor.

Abstract: Various methods of detecting a found rotor, a lost rotor, a locked rotor and a caught rotor after a power disruption using flux estimates are disclosed. Also disclosed are permanent magnet motor controllers and assemblies suitable for performing one or more of these methods.

Abstract: A mode determination circuit is configured to determine whether there is a status change of the electric system associated with a frequency variation of a system control clock, and a clock change circuit is configured to change the system control clock from a system clock to a monitoring clock based on a determination result obtained by the mode determination circuit.

Abstract: A method for is disclosed for using pulse-width modulated (PWM) signals in the control of a plurality of electric motors or of at least one electric motor with multiple windings. The method comprises steps of: measuring the current being drawn by each of said electric motors; transmitting signals corresponding to the current being drawn said plurality of motors to a central controller; transmitting from said central controller signals corresponding to the amount of current to be drawn by each motor, whereby the relative phases and durations of said signals are distributed according to a predetermined protocol; and repeating steps (a) through (c) while said electric motors are in operation. The distribution of PWM signals defines the total current drawn from said source of electricity as a function of time.

Abstract: An inverter includes a voltage command generator generating a voltage command value according to an externally specified voltage value, a PWM signal generator generating a PWM signal according to the voltage command value and frequency command value, and a switching unit generating a three-phase AC power according to the PWM signal. The voltage command generator decreases the voltage command value if the output current increases, to prevent the rotation speed of a prime move from suddenly changing. If the output current exceeds a preset upper current threshold, the voltage command value is clamped at a preset minimum output voltage, thereby securing the minimum output voltage for an increase in the output current.

Abstract: Identification of electrical equivalent circuit parameters (15) of a three-phase asynchronous motor (09) without a shaft encoder. The method comprises—Assumption of a standstill position of the rotor (11);—Equidirectional test signal infeed U1?, U1? in ? and ? in the stator axis direction of the asynchronous motor (09);—Measuring of a measuring signal I1?, I1? of the ? and ? axial direction of the asynchronous motor (09); and—Identification of equivalent circuit parameters of the asynchronous motor (09) on the basis of the test signal voltages U1?, U1? and of the measuring signal currents I1?, I1?; whereby the test signal feed allows the rotor (11) to remain torque-free. Determination of equivalent circuit parameters (15) of an asynchronous motor (09) as well relates to a motor control device (35), whereby the identified equivalent circuit parameters (15) can be used for the determination, optimization and monitoring of a motor control and for control of electrical drives.

Abstract: Solid state switches of inverters are controlled by timing signals computed in power layer interface circuitry for individual inverters. Multiple inverters may be placed in parallel with common three-phase output. Common control circuitry generates timing signals or data used to reconstruct the common signals and sends these signals to the power layer interface circuitry. A processor in a power layer interface circuitry used these signals to recomputed the timing signals. Excellent synchronicity may be provided between parallel inverters that each separately reconstruct the timing signals based upon the identical received data.

Abstract: Embodiments of the present invention relate to methods, systems, a machine-readable medium operable in a controller, and apparatus for controlling a multi-phase inverter that drives a multi-phase electric machine. When a sensor fault is detected, a phase current angle is computed based on the feedback stator currents, and used to estimate an angular velocity and an angular position of a rotor of the multi-phase electric machine. When the estimated angular velocity of the multi-phase electric machine is less than a transition angular velocity threshold, an open-circuit response can be applied at the multi-phase inverter by controlling all switches in the multi-phase inverter drive to be open. By contrast, when the estimated angular velocity is greater than the transition angular velocity threshold, a short-circuit response can be applied at the multi-phase inverter by controlling selected switches in the multi-phase inverter drive to connect all phases of the multi-phase inverter to a single bus (e.g.

Abstract: An energy converter includes a magnetism generation mechanism unit that generates a magnetic field when connected to an AC electrical power source, and a rotating mechanism unit having a single turn coil array member in which a plurality of single turn coils is disposed at a predetermined interval and a soft magnetic metal plate disposed on a side of the single turn coil array member opposite to the magnetism generation mechanism unit. The rotating mechanism unit is structured such that the single turn coil array member faces the magnetism generation mechanism unit across a predetermined magnetic gap and rotary driven by the magnetic field. Here, a drive signal period of the electrical power source is a period that maximizes an eddy current generated in the soft magnetic metal plate.

Abstract: A drive control device which estimates an engine torque during traveling in a fixed gear ratio mode is disclosed. The drive control device includes the engagement mechanism including the revolution component revolved by the torque of the engine and the fixed component that engages with the revolution component, the torque applying unit which applies torque to the revolution component and the first transmitting control unit which engages the engagement mechanism to make the engagement mechanism receive the reaction force of the torque. The torque estimating control unit executes control of torque applied to the revolution component by the torque applying unit during executing the control by the first transmitting control unit to detect the phase change between the revolution component and the fixed component and estimates the torque of the engine based on the phase change and torque applied by the torque applying unit.

Abstract: A phase control apparatus includes a first transistor whose source or emitter is connected to one end of an AC power supply and whose drain or collector is connected to one end of a load, a second transistor whose source or emitter is connected to the other end of the AC supply and whose drain or collector is connected to the other end of the load, a diode bridge that rectifies an AC voltage of the AC supply, and a parallel circuit of a zener diode and a capacitor. The parallel circuit generates a high potential relative to a bridge negative output terminal potential, or generates a low potential relative to a bridge positive output terminal potential. First and second transistor control terminal potentials are switched between the high and the bridge negative output terminal potentials, or between the low and the bridge positive output terminal potentials.

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

Abstract: A DCDC converter includes a switching circuit, to an input end of which an input filer circuit is connected, a smoothing filter circuit connected to an output end of the switching circuit and including a reactor and a capacitor, and a control unit that feeds back a state amount of the smoothing filter circuit and turns the switching circuit on and off. The control unit includes a damping control unit that calculates, based on the voltage of the capacitor, a damping operation amount for adjusting a state amount of the smoothing filter circuit.

Abstract: A rotation detecting apparatus for detecting a rotational state of a direct-current motor includes a driving device, a control device, an energization detecting device, an alternating-current component detecting device, and a rotational state detecting device. An impedance between brushes of the motor changes periodically in accordance with rotation of the motor. The alternating-current component detecting device detects change of an alternating-current component of electric current that is supplied to the motor based on an electrical quantity. The change of the alternating-current component is caused by change of the impedance caused in accordance with the rotation. The rotational state detecting device detects at least one of a rotation angle, a rotational direction, and a rotational speed of the motor based on a detection result of the alternating-current component detecting device.

Abstract: An electric power tool according to the present invention is provided with a tool main body, an induction motor, a power supply unit, and an inverter. The power supply unit and the inverter are integrally incorporated in the tool main body together with the induction motor.

Abstract: An adjustable frequency drive includes a base having a first portion and a second portion, and an active front end converter disposed on the base. The converter includes an input, an output, and a plurality of first electronic switches electrically connected between the input and the output. An inverter is disposed on the base and includes an input electrically connected to the output of the active front end converter, an output, a plurality of capacitors disposed on the first portion of the base and electrically connected to the input of the inverter, a plurality of second electronic switches disposed on the second portion of the base and electrically connected between the input and the output of the inverter, and a heat pipe assembly. The inverter is structured to provide a single, three-phase output structure.

Abstract: Various methods of detecting a found rotor, a lost rotor, a locked rotor and a caught rotor after a power disruption using flux estimates are disclosed. Also disclosed are permanent magnet motor controllers and assemblies suitable for performing one or more of these methods.

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

Abstract: The present invention provides a medium voltage variable frequency driving system, including a three-phase switch-mode rectification module, a multilevel inverter and a high-capacity capacitor module. The three-phase switch-mode rectification module is coupled with a three-phase electrical grid, for converting an AC voltage input with a fixed operating frequency on the three-phase electrical grid into a DC voltage. The multilevel inverter is used for converting the DC voltage into an AC voltage with a required variable frequency, so as to drive an induction motor. The high-capacity capacitor module is coupled between the three-phase switch-mode rectification module and the multilevel inverter, for temporarily storing the DC voltage. In the present invention, a three-phase switch-mode rectification technology is used at the front-end rectifier, and a diode-clamped three-level inverter is adapted correspondingly at the rear-end inverter.

Abstract: A method of braking a washing machine from an operational speed to a reduced non-zero speed is provided (as well as a washing machine incorporating the method) for a washing machine driven by one of a synchronous or asynchronous motor. Upon receipt of a speed reduction signal, the motor rotating magnetic fields are collapsed for a defined time period. After the defined time period, DC braking voltage is applied to the motor stator windings at a controlled ramp-up rate to an amplitude to generate a controlled ramped braking torque on the motor until the motor has slowed to a defined reduced speed. Thereafter, the amplitude of the DC braking voltage is set to 0V and the motor is soft started to an amplitude and reduced frequency needed to maintain the defined reduced speed.

Abstract: A conveyor system includes an electric motor to move a conveyor. A voltage determining device is coupled to an alternating-electricity source that supplies alternating electricity to the conveyor system. A power supply appliance supplies power between the electric motor and the alternating-electricity source. The power supply appliance includes an inverter and an inverter control. The inverter includes a rectifying bridge and a motor bridge. The rectifying bridge input is coupled to the alternating-electricity source and the rectifying bridge output is coupled to the motor bridge input. The motor bridge output is coupled to the electric motor. The inverter control is coupled between the voltage determining device and the motor bridge. The inverter control is responsive to frequency and phase of the determined voltage of the alternating-electricity source to adjust the frequency and phase of the motor bridge output voltage such that the motor bridge output voltage is made to be essentially constant.

Abstract: A control device for an asynchronous electric machine comprising a first computing unit configured for defining a first signal, indicating a desired slip frequency of the electric machine, as a function of a second signal correlated to a reference input velocity supplied through a user interface, and of a third signal correlated to a detected rotor angular velocity, the control device preferably comprising a user interface for supplying the second signal and a velocity-detection module coupled to the electric machine for supplying the third signal.

Abstract: Methods and devices are presented herein for estimating induction motor inductance parameters based on instantaneous reactive power. The induction motor inductance parameters, e.g., the stator inductance and the total leakage factor, can be estimated from motor nameplate data and instantaneous reactive power without involving speed sensors or electronic injection circuits.

Abstract: A method of detecting a phase winding fault in a multi-phase electric machine is executable via a motor controller, and includes measuring feedback signals of the machine, including each phase current, and generating reference phase voltages for each phase. The method includes calculating a predetermined voltage value using the feedback signals and reference phase voltages, and comparing the voltage value to a corresponding threshold to determine the fault. A control action is executed when the voltage value exceeds the corresponding threshold. The voltage value is one or more of: a ratio of a normalized negative sequence voltage to a modulation index, an RMS voltage for each phase, and total harmonic distortion of each phase current. An apparatus detects the fault, and includes a motor controller and an algorithm as set forth above. The apparatus may include a voltage inverter for generating a multi-phase alternating current output for powering the machine.

Abstract: A motor drive system includes: a three-phase motor; a power conversion device that supplies power for driving the three-phase motor; and an output filter that is arranged between an output of the power conversion device and the three-phase motor and has a configuration in which a setting value of a filter resonance frequency is selectable and changeable.

Abstract: The motor drive circuit 100 supplies a drive current to the motor 2 to drive the motor. Each of the first Hall amplifier HAMP1 to the third Hall amplifier HAMP3 is provided for each phase of the motor 2 and receives a pair of Hall signals from a corresponding phase Hall element to generate each phase sine wave voltage SIN_U, SIN_V and SIN_W by amplifying a difference between the pair of Hall signals. Each of the first PWM comparator PCMP1 to the third PWM comparator PCMP3 is provided for each phase of the motor 2 and compares the corresponding phase sine wave voltage SIN_U, SIN_V and SIN_W, with the periodic voltage Vosc to generate each phase PWM signal PWM_U, PWM_V and PWM_W. The drive unit 10 subjects a phase coil, a target to be driven, to pulse drive by using the pulse modulated signal from the corresponding PWM comparator.

Abstract: An apparatus operable in a wet environment includes a voltage doubler circuit including a pair of diodes, a pair of direct current switching elements connected between the respective diodes and a common point, a controller, an interface connected to the controller for receiving external status signals, and a switching arrangement responsive to signals from the controller to select the full power mode or a controlled power mode. In the controlled power mode, the switching elements are switched in a predetermined sequence such that only one of the switching elements conducts current during any one half cycle of the AC output voltage applied to the motor.

Abstract: Methods and systems for controlling an electric motor are provided. A signal comprising at least first and second cycles is provided to the electric motor. A first flux value for the electric motor associated with the first cycle of the signal is calculated. A second flux value for the electric motor associated with the second cycle of the signal is calculated based on the first flux value.

Abstract: This invention relates to an apparatus and method for deriving speed and position information for an electric motor. Apparatus for and a method of controlling a motor 100 are also disclosed. The apparatus for providing information relating to the operation of an electrical motor 100 comprises a sampler 50, 51 for sampling the instantaneous motor current is and a processor 160 for determining the instantaneous rate of change of the motor current and providing information about the motion or position of said motor based on said instantaneous rate of change of the motor current. In this way speed and position information can be provided, at low speeds, and without using a speed sensor.

Abstract: A system and method for controlling an AC motor drive includes a control system programmed with an energy algorithm configured to optimize operation of the motor drive. Specifically, the control system receives input of an initial voltage-frequency command to the AC motor drive, receives a real-time output of the AC motor drive generated according to the initial voltage-frequency command, and determines a real-time value of a motor parameter based on the real-time output of the AC motor drive. The control system also inputs a plurality of modified voltage-frequency commands to the AC motor drive, determines the real-time value of the motor parameter corresponding to each of the plurality of modified voltage-frequency commands, and identifies an optimal value of the motor parameter based on the real-time values of the motor parameter.

Abstract: An electric motor control circuit includes an electric energy storage device electrically connected via DC power buses to an inverter circuit that connects via an alternating current circuit to an electric machine. A capacitive shunt circuit connects between the power buses. Current flow through the capacitive shunt circuit to the chassis ground is monitored. A fault is identified when the current flow through the capacitive shunt circuit to the chassis ground exceeds a threshold.

Abstract: The adapting system for a resonant drive appliance includes a circuit for measuring the back EMF induced in the stator coil of the motor following turn-off of the appliance. The frequency of the back EMF signal is determined from the zero crossings of the EMF signal. The determined frequency is then compared with a running average of previous frequency determinations, and the drive frequency of the appliance is adjusted if the difference between the compared frequencies is greater than a threshold value, e.g. 1 Hz.

Abstract: A multilevel inverter is provided. The multilevel inverter includes a plurality of bridges, each bridge configured to receive a respective portion of an input DC power and convert the respective portion to a respective converted AC power. The multilevel inverter also includes at least one bridge controller for operating at least one of the plurality of bridges in a square waveform mode. The multilevel inverter further includes a plurality of transformers, each transformer coupled to a respective bridge and configured to increase a voltage level of the respective portion of converted AC power. The plurality of transformers further includes secondary windings coupled in series with the other secondary windings to combine the respective increased voltage level portions of the converted AC power. The multilevel inverter also includes a grid converter configured to provide output power for a power grid.

Abstract: A method and an apparatus for the failsafe monitoring of an electromotive drive without additional sensors, including a drive having a three-phase control of an electric motor, detection of the current and voltage profiles of each of the three phases, as they are forwarded to the motor by drive electronics, determination of the load speed while using the detected current and voltage values, where the determination of the load speed takes place by calculating an observer model with reference to the detected current, to the detected voltage, to the frequency preset by the control and to the characteristic data of the motor and generation of a failsafe switch signal for the motor when the calculated load speed does not correspond to a preset desired speed within the framework of preset tolerances. The load torque can also be determined and monitored with reference to the observer model.

Abstract: A motor control device includes a current profile generator generating a current profile, a pilot voltage operator calculating a pilot pulse voltage, on the basis of the current profile, and adding the pilot pulse voltage to a voltage command on a d axis, a magnetic pole position detector detecting a position of a magnetic pole in the permanent magnet motor, on the basis of the pilot pulse voltage, a polarity identification evaluation current operator calculating a polarity identification evaluation current for identifying a polarity of the magnetic pole in the permanent magnet motor, on the basis of a current value on the d axis in the motor current that has been detected in synchronization with a period of PWM control, and a polarity detector outputting a phase correction amount, on the basis of a deviation between the polarity identification evaluation current and the current profile.

Abstract: When output voltage V1 of an electric power converter reaches a prescribed voltage V1*ref, a difference between V1 and V1*ref is integrated to correct a commanded torque to ?o* (?*=?o*+??).

Abstract: A control system is provided for an inverter assembly associated with an induction motor. The system includes a current determination module configured to generate q- and d-axis current commands based on a torque command. The current determination module is further configured to generate the q-axis current command based on an observed flux linkage and a flux linkage command. The system further includes a motor current control module coupled to the current determination module and configured to generate q- and d-axis voltage commands based on the q- and d-axis current commands generated by the current determination module and a PWM modulator coupled to the motor current control module configured to generate duty cycle signals for operating the inverter assembly based on the q- and d-axis voltage commands generated by the motor current control module.

Abstract: A sensorless induction motor control device with a function of correcting a slip frequency wherein a slip frequency estimation unit estimates the slip frequency from at least one kind of current flowing through the motor. A voltage command value calculation unit calculates a D-phase voltage command value and a Q-phase voltage command value which are used for controlling a voltage applied to the motor using a Q-phase current command value calculated based on a difference between a speed estimation value, which is calculated using an estimation value of the slip frequency, and an externally supplied speed command value. An ideal voltage command value determination unit determines an ideal voltage command value using the speed command value and the Q-phase current command value. An actual voltage command value calculation unit calculates an actual voltage command value using the D-phase voltage command value and the Q-phase voltage command value.

Abstract: A jack-up platform (1) has a hull (2) and at least three longitudinally movable support legs (3) for the hull (1), at least one of the support legs (3) has at least one variable speed drive (8, 8A1 to 8F2) as a part of a leg driving mechanism, wherein the platform (1) has a closed-loop control unit (7) for the driving mechanism, the closed-loop control unit (7) being connected with the variable speed drive (8, 8A1 to 8F2) via a bi-directional electronic bus (16) for transmitting control parameters (M*,M,N,R).

Abstract: A motor driver, including a bridge circuit including a switching element and a diode, connecting with a coil terminal of each phase of a polyphase motor; a modulator modulating a voltage value applied to the coil terminal of each phase such that a minimum voltage value applied thereto is zero; a PWM signal generator generating a PWM signal, based on the voltage value applied to each phase, which is modulated by the modulator; and a switching element drive signal generator generating a switching element drive signal to drive the switching signal, based on the PWM signal generated by the PWM signal generator.

Abstract: A motor drive device including a converter for a power running operation and a power regenerative operation. The converter has power switching elements, a first power regenerative control unit for controlling the power switching elements in the power regenerative operation by using pulse width modulation signal whose pulse width changes with a value indicated by a command signal; a second power regenerative control unit for controlling the power switching elements in the power regenerative operation to generate respective power regenerative currents in a phase representing the maximum potential among three phases of a three-phase AC power supply and a phase representing the minimum potential among the three phases, and a power regenerative operation switching unit for switching a control of the power switching elements in the power regenerative operation between a control by the first power regenerative control unit and a control by the second power regenerative control unit.

Abstract: A drive control signal is effectively obtained. An offset control circuit (32) adds an offset to a rotational state signal.

Abstract: A control device that controls a plurality of inverters respectively provided corresponding to a plurality of alternating-current electric motors so as to control the plurality of alternating-current electric motors by current feedback. The control device comprises a carrier frequency setting unit that individually selects and sets one of a plurality of carrier frequencies, each of which is a frequency of a carrier for generating switching control signals for the inverter based on a pulse width modulation method, for each of the plurality of inverters, and a switching timing table that specifies a switching timing serving as a permissible timing of switching to a different carrier frequency pair from each of a plurality of carrier frequency pairs each of which is composed of a combination of the carrier frequencies set for each of the plurality of inverters.

Abstract: A winding switching apparatus includes a winding switching device and a drive circuit. The winding switching device is configured to switch a plurality of windings of an AC motor. The drive circuit is configured to control the winding switching device. The winding switching device includes a winding switch, a diode bridge, and a capacitor. The diode bridge includes a positive-side DC output terminal, a negative-side DC output terminal, and AC input terminals. The AC input terminals corresponds to respective phases of the AC motor. The positive-side and negative-side DC output terminals are respectively connected to positive-side and negative-side DC buses provided in an inverter. The AC input terminals are respectively connected to winding-switching terminals corresponding to the respective phases of the AC motor. The AC input terminals are respectively connected to phase terminals provided in the winding switch.

Abstract: A power converter includes: a determination section which, prior to an actual operation, determines presence/absence of a common mode filter connected to a line for supplying power to a motor, switching elements being driven with a predetermined PWM on/off drive signal corresponding to a carrier frequency prior to the actual operation; and a PWM control method changing/setting section which, during the actual operation, changes and sets a PWM control method in accordance with a result of the determination of the presence/absence of the common mode filter.

Abstract: A microcomputer that controls an ultrasonic motor includes a storage unit that stores a compare register value, and a digital/analog (D/A) conversion set value, a D/A converter that generates an amplitude control signal with an amplitude value corresponding to the D/A conversion set value, a timer that generates a pulse width modulation (PWM) signal with a frequency corresponding to the compare register value, a central processing unit (CPU) that reads the D/A conversion set value, and the compare register value from the storage unit, and that sets the D/A conversion set value and the compare register value to the D/A converter and the timer, respectively, and an output circuit that generates the control signal with the amplitude of the amplitude control signal, and the frequency of the PWM signal, in response to the amplitude control signal and the PWM signal.

Abstract: A fan device with improved speed control module includes a stator, a rotor, and a speed control module. The stator has a driving unit outputting currents for the stator to generate alternative magnetic fields and thus turn the rotor. The speed control module includes a control unit and a speed adjusting circuit, with the control unit generating a control command for the driving unit and further outputting a state signal for the speed adjusting circuit to control whether a PWM signal enters the control circuit or not.

Abstract: A multi-phase outer-rotor-type variable frequency induction motor for a ceiling fan includes: an outer rotor disposed in a housing that includes a plurality of blade-mounting parts, and including a stator-mounting part that is surrounded by an outer rotor body which is combined with the housing, the outer rotor body being formed with a plurality of slots in which conductive elements are respectively disposed; a stator disposed in the stator-mounting part, and including a central shaft pivotally connected to the housing, a stator core extending in radial directions from the central shaft, and a winding set that is disposed to wind in winding slots formed in the stator core, and that is configured into a multi-phase winding arrangement; and a control unit operable to control frequency of a power signal fed by the control unit to the winding set.

Abstract: A method of controlling a power converter in an electric drive machine is disclosed. The method may include determining a first switching frequency and determining a second switching frequency. The method may also include comparing the first switching frequency and the second switching frequency. The method may further include selecting a power converter switching frequency from the lesser of the first switching frequency and the second switching frequency to control a power converter.