Abstract: The invention relates to an electric motor having a stator and a rotor. The electric motor also comprises a controller, wherein the controller is connected to the stator and/or rotor, and is designed for applying current to the stator and/or rotor for rotating the rotor. According to the invention, the controller comprises a pulse width modulator designed for controlling a power output of the electric motor, in order to generate a predetermined number of different current application patterns. The current application patterns each represent a power output of the electric motor, and preferably comprise a time sequence of current pulses, each having a current pulse duration.

Abstract: A method is provided. A command to correspond to a target speed of a motor is received. A rotational speed of the motor is measured, and a brake-to-off ratio for a braking interval is calculated based at least in part on the rotation speed, the target speed, a braking parameter. An off state for an inverter that is coupled to motor is induced during an off portion of the braking interval, and a brake signal is applied to the inverter during a braking portion of the braking interval.

Abstract: A system for identifying magnetizing inductance and rotor resistance of an induction machine comprises an induction machine comprising a rotor and a stator, a DC voltage bus, and a DC-to-AC voltage inverter coupled to the DC voltage bus and to the induction machine. The system also comprises a controller configured to cause the DC-to-AC voltage inverter to apply a square-wave excitation to a plurality of phases of the induction machine, determine a stator resistance of the stator of the induction machine based on the square-wave excitation, and determine a rotor resistance of the rotor of the induction machine based on the square-wave excitation. The controller is also configured to calculate a magnetizing curve for the induction machine based on the stator and rotor resistances and control the induction machine to operate based on the magnetizing curve.

Abstract: Provided is an apparatus for compensating offset of a current sensor detecting a motor current supplied by an inverter for PWM (Pulse Width Modulation) control of a motor, the apparatus including a current controller providing a PWM signal generated based on the motor current detected by the current sensor to the inverter, calculating an offset using the motor current detected by the current sensor in response to presence and absence of the PWM control of the motor, or offset-compensating the motor current detected by the current sensor.

Abstract: An inverter apparatus basically includes an inverter, a rotational speed detecting component and a control component. The inverter includes a plurality of pairs of switching elements. The control component controls an on-off status of the switching elements to convert a direct current from a direct current power source into alternating current by alternately executing first and second controls when a rotational speed of a motor connected to the switching elements is larger than a prescribed rotational speed. The first control turns on the switching elements that are directly connected to a positive electrode of the power source, and turns off the switching elements that are directly connected to a negative electrode of the power source. The second control turns on the switching elements that are directly connected to the negative electrode and turns off the switching elements that are directly connected to the positive electrode.

Abstract: A controller for a DC motor comprises an output switching element configured to couple to the DC motor; an input switching element coupled to the output switching element; a pulse width modulated (PWM) signal coupled to a control terminal of the input switching element and a supply voltage applied to the output switching element. A resistive-capacitive (RC) network may be coupled to a control terminal of the output switching element, with the RC network being configured to integrate the PWM signal into a DC voltage. A first resistive network may be configured to set a bias for the output switching element when the input switching element is turned off, and a second resistive network may be configured to set the bias for the output switching element when the input switching element is turned on, such that the controller is effective to provide zero-to-full supply voltage control to the DC motor.

Abstract: In a control device for a three-phase rotating machine with first and second winding sets, a current feedback computing section includes a current sum controller and a current difference controller. The current sum controller multiplies, by a sum gain, an error between a sum of current command values for alternating currents output from first and second inverters and a sum of sensed current values and computes a sum of voltage command values. The current difference controller multiplies, by a difference gain, an error between a difference of the current command values and a difference between the sensed current values, and computes a difference of voltage command values. In a variable-responsiveness mode, a gain ratio between the sum gain and the difference gain is varied according to a reference frequency such that the current sum controller and the current different controller are different in responsiveness.

Abstract: A rotation speed control circuit is disclosed. The rotation speed control circuit includes a temperature-controlled voltage duty generator, a pulse-width signal duty generator, a multiplier and a rotation speed signal generator. The temperature-controlled voltage duty generator converts temperature-controlled voltage to digital temperature-controlled voltage and executes linear interpolation operation according to a first setting data so as to output temperature-controlled voltage duty signal. The pulse-width signal duty generator coverts pulse-width input signal to a digital pulse-width input signal and executes linear interpolation operation according to a second setting data so as to output a pulse-width duty signal. The temperature-controlled voltage duty signal and the pulse-width duty signal are executed for multiplication by the multiplier so as to output mixing-duty signal.

Abstract: A method for operating a direct current (DC) motor is shown and described. The method includes using pulse width modulated (PWM) DC output to control the speed of the DC motor. The method further includes sensing current output to the motor. When the sensed current exceeds a threshold, the method holds the PWM DC output off.

Abstract: A power conversion method including: receiving an input voltage which is a single-phase AC voltage; designating a first target voltage and a second target voltage respectively representing consecutive target values of a first-phase output voltage and a second-phase output voltage which form a two-phase AC voltage; cyclically connecting and disconnecting a pair of input terminals and a pair of first output terminals at a duty cycle corresponding to a ratio |ref1/in| during a time period in which an instantaneous absolute value of the input voltage is greater than an instantaneous absolute value of the first target voltage; and cyclically connecting and disconnecting the pair of the input terminals and a pair of second output terminals at a duty cycle corresponding to a ratio |ref2/in| during time periods in which the instantaneous absolute value of the input voltage is greater than an instantaneous absolute value of the second target voltage.

Abstract: A wind energy system that converts fluctuating wind into electrical power, wherein part of the electrical power is converted into variable AC electrical power and fed into the grid, part is converted into DC power, and part is converted into heat.

Abstract: A motor control circuit and associated techniques detect a zero crossing of a current in a motor winding by detecting a reverse current in a half bridge circuit used to drive the motor winding.

Abstract: An ECU executes a program including a step of detecting the rotation speed of a motor, a step of determining the diffusion width of carrier frequency, a step of determining the carrier frequency based on the determined diffusion width, a step of generating a carrier signal based on the determined carrier frequency, and a step of executing pulse width modulation based on an AC voltage command and the carrier signal.

Abstract: The excitation overcurrent detection unit for the doubly-fed electric machine is provided with a function to determine an excitation current magnitude relationship among three phases. The firing pulse is held to on-state or off-state to cause the largest-current phase and the second-largest-current phase to charge the DC capacitor by the operation of diodes. The conduction ratio of the third-largest-current phase or minimum current phase is controlled according to the detected current value to protect against a possible short-circuit across the DC capacitor. When the voltage of the DC capacitor exceeds a preset value, the voltage is suppressed by operating active or passive power devices.

Abstract: A motor control system is provided, including a motor and a control module. The motor operates at a rotational velocity, and creates a regenerative current. The motor has a target field weakening current that is configured for limiting the regenerative current to a threshold value. The control module is in communication with the motor. The control module receives a motor torque command. The control module includes control logic for identifying the target field weakening current based upon the motor torque command and the rotational velocity of the motor.

Abstract: A command rotation speed is set to an initial rotation speed, and a forced commutation mode is started. In the forced commutation mode, a rotation speed is increased by a predetermined increase amount each time and forced commutation is executed until the rotation speed reaches a set rotation speed. Then, a switchover to the sensorless control mode is made when the rotation speed reaches the set rotation speed (S4) and a rotor position becomes detectable.

Abstract: A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.

Abstract: A circuit arrangement, especially for supplying an electromagnetic holding brake with a clocked supply voltage, includes a module for controlled provision of a clocked supply voltage for free-wheeling operation of the holding brake. The module has a switching unit for switching off the supply voltage for braking operation. A free-wheeling diode and a suppressor diode are connected in parallel to an inductance of the holding brake, with the free-wheeling diode being effective in free-wheeling operation only and the suppressor diode being effective in braking operation only.

Abstract: A motor control method comprises: inputting a PWM signal into a control unit for the control unit to obtain a direction command and a speed command by an identification rule, and generating a control signal according to the direction and speed commands by the control unit; and generating a driving signal according to the control signal by the driving unit for driving a motor to operate according to the direction and speed commands.

Abstract: Method and device for operating an asynchronous motor having increased efficiency. According to the invention, ranges for a motor size of the asynchronous motor are specified. In addition, a value of the motor size is calculated depending on at least one measurement value of a measurement parameter during the operation of the asynchronous motor, wherein the respective calculated value of the motor size is allocated to one of the ranges. Furthermore, a control parameter is changed depending on the range to which the calculated motor parameter is allocated to provide an optimised control parameter such that the control parameter is changed beginning from a starting value specified for the respective range of the motor size until a predetermined criterion for a specific motor size is reached. Furthermore, the optimised control parameter is stored as a support point of a continuous optimal characteristic curve for the control parameter depending on the range to which the calculated motor size is allocated.

Abstract: An inverter and a control unit that has a command signal processing unit and a PWM frequency control unit and performs pulse width modulation control are provided. If the command signal processing unit has received a first PWM frequency command signal, it outputs a low PWM frequency command signal so that synchronous or asynchronous PWM control is performed at a PWM frequency in a predetermined frequency range. The command signal processing unit outputs a high PWM frequency command signal so that synchronous or asynchronous PWM control is performed at a higher frequency than the above-mentioned frequency if the command signal processing unit has received a second PWM frequency command signal and until a predetermined time period elapses. The command signal processing unit outputs a low PWM frequency command signal if it has received the second PWM frequency command signal and after the predetermined time period elapsed.

Abstract: The present invention is provided to remove dust that adhered to a cooling fan. A plurality of comparators are disposed for each of a plurality of coils, respectively, and generates a back electromotive force sensing signal denoting a comparison result by comparing a back electromotive force appearing at one end of each corresponding coil with a neutral-point voltage of the coils. A driving signal synthesis circuit generates a driving control signal used to enable the fan motor to proceed the following actions: (i) enabling the fan motor to rotate toward the opposite direction as a normal operation within a specific reverse rotation period after a driving of the fan motor is started, (ii) applying a brake to the fan motor within a braking period, and (iii) enabling the fan motor to rotate toward a direction of normal operation in a normal driving period. A driving circuit drives the fan motor.

Abstract: A motor driving device and a driving method thereof is disclosed herein and comprises a PWM converting circuit, an oscillator, a comparator, a controlling unit. The PWM converting circuit converts an analog signal according to an adjustable the highest setting voltage, an adjustable the lowest setting voltage and a controlling signal. The analog signal and a triangular signal generated by the oscillator are inputted to the comparator to compare to output a drive signal to the controlling unit so as to control the motor speed. The motor driving device in the present invention can adjust the motor rotating speed curve to set the lowest rotating speed of the motor so as to achieve the function of changing the motor rotating speed and maintain the lowest torque of the motor to increase the flexibility of the motor speed control.

Abstract: A control device for an induction machine includes an angle determining device designed to determine a rotor angle of the induction machine without requiring use of sensors. The angle determining device generates measuring voltage pulses which can be selectively used to replace control voltage pulses used to control the induction machine. Machine currents generated by the measuring voltage pulses can be used to determine a rotor angle without interrupting the control voltage pulses and/or operation of the induction machine.

Abstract: A motor control apparatus that is capable of making the whole control system robust not only with respect to motor parameter variations such as the temperature variation and the manufacturing unevenness but also with respect to disturbances while using a cheap and compact one-shunt type current detecting circuit and simultaneously diagnosing an estimation error and an electric power steering apparatus provide with the motor control apparatus.

Abstract: A method for driving a motor is provided. Pulse width modulation (PWM) signals are generated from a voltage signal and a commanded angle signal, which drives a motor with multiple phases. A motor current from a motor is measured with a single shunt and converted into a digital signal. Based on the digital signal and the commanded angle signal, direct-axis and quadrant-axis currents for the motor can be determined, and the voltage signal and the commanded angle signal can be adjusted based at least in part on the direct-axis and quadrant-axis currents.

Abstract: Disclosed is a power supply module for a hall sensorless BLDC motor, including: a high-voltage/large-current power device t applied with high voltage/large current and including a plurality of power devices driving the hall sensorless brushless direct current (BLDC) motor; a motor driving circuit sensing and controlling a positional signal or a velocity signal of the hall sensorless BLDC motor and generating a PWM control signal for controlling the hall sensorless BLDC motor; and a power device driving circuit driving the high-voltage/large-current power device according to the PWM control signal of the motor driving circuit, wherein the high-voltage/large-current power device, the power device driving circuit, and the motor driving circuit are CMOS-integrated on the same substrate.

Abstract: A method of operating a laundry treating appliance to control a rotational speed of a drum to move the laundry within the drum according to a predetermined category of movement.

Abstract: A controller includes: an inverter having switching devices for converting by a PWM method and supplying an electric power to a multi-phase rotary device; a duty calculator calculating a duty command value with To; a pseudo duty calculator calculating a N-th update duty value based on N-th and (N?1)-th duty command values according to a ratio of To/Tr with a linear compensation method; a comparator comparing the update duty value with a carrier wave to generate an on-off signal of each switching device; and a detector detecting current of each phase with To. The duty calculator changes an average voltage of each phase to make an on-state time of a detection side switching device equal to or longer than minimum. When the on-state time at one phase is smaller than minimum, the pseudo duty calculator outputs a pseudo duty value to detect the current of other phases.

Abstract: Disclosed herein is a motor control apparatus and a method thereof. The operation efficiency of a compressor may be maintained by using a sensorless algorithm, sampling a current applied to a motor more than twice within a period of the triangular carrier wave for performing pulse width modulation to calculate a reference voltage, driving the motor according to the calculated reference voltage to improve control resolution, and performing a high-speed operation while reducing a volume of the compressor, without adding a separate hardware when controlling the operation of the motor provided in the compressor at a high speed.

Abstract: A motor controller is disclosed. The motor controller includes a current detector that is provided in a direct current side of a power converter and that detects direct current information. A determiner determines a size of an offset voltage contained in the detected current information. The determiner calculates the offset voltage by canceling a positive current component by a negative current component both pertaining to the same one phase and contained in the detected direct current information. A modifier modifies the detected direct current information based on the calculated offset voltage.

Abstract: A PWM-signal-output circuit includes a detecting unit to detect periods in which a speed signal with logic level changing alternately and having a period corresponding to a motor-rotation speed is at one and the other logic levels, a dividing unit to divide each of the periods into first to third periods; a first output unit to change a PWM-signal duty-cycle in a stepwise manner toward an input-signal duty-cycle in the first period, a second output unit to cause a PWM-signal duty-cycle to become equal to an input-signal duty-cycle, to maintain a current flowing through the motor coil constant, in the second period; and a third output unit to change a PWM-signal duty-cycle in a stepwise manner from an input-signal duty-cycle, to decrease a current flowing through the motor coil, in the third period.

Abstract: A motor controller (4) and method for maximizing the energy savings in an AC induction motor (3) at every load wherein the motor is calibrated at two or more load points to establish a control line (6), which is then programmed into a non-volatile memory (30) of the motor controller. A DSP-based closed-loop motor controller observes the motor parameters of the motor such as firing angle/duty cycles (23), voltage (37), current (9) and phase angles to arrive at a minimum voltage necessary to operate the motor at any load along the control line. The motor controller performs closed-loop control to keep the motor running at a computed target control point, such that maximum energy savings are realized by reducing voltage through pulse width modulation.

Abstract: Power conversion systems with active front end converters for example motor drives and power generation systems for distributed energy sources are presented with adaptive harmonic minimization for grid-tie converters for minimized or reduced total harmonic distortion in the line current spectrum including the source harmonic current, the load harmonics and the PWM harmonics.

Abstract: A polyphase electrical machine controlled by at least two parallel inverters, each including a number of branches equal to a number of phases of the machine and controlled by PWM. When detecting an inverter branch is faulty, the faulty branch is isolated and the phase in question is powered by each corresponding other inverter branch. The PWM is modified to make power switches of each other branch conductive in succession, without switching while absolute value of the current of the phase in question is greater than or equal to a threshold of 80% to 120% of (n?1)Imax/n, n is number of inverters and Imax is maximum magnitude of the phase current. It is thus possible to continue generating substantially sinusoidal voltages on each of the phases, while avoiding overdimensioning the power switches to ensure in event of a fault they can deliver currents of amplitude higher than in normal operation.

Abstract: A motor driving apparatus is disclosed herein and includes a control unit, a soft-start unit and an output unit. When power-up or lock release situation, an external PWM driving signal is inputted to the soft-start unit, the soft-start unit generates an internal PWM driving signal and a power-up initial signal; after the power-up initial signal is generated, the control unit transmitting a motor rotation signal to the soft-start unit; when the soft-start unit counts a plurality of the motor rotation signal, the soft-start unit selects the external PWM driving signal or the internal PWM driving signal to output to the output unit.

Abstract: Embodiments of the present method and system permit an effective method for determining the optimum selection of pulse width modulation polarity and type including determining machine parameters, inputting the machine parameters into a predicted duty cycle module, determining the optimum polarity of the pulse width modulation for a predicted duty cycle based on a pulse width modulation generation algorithm, and determining the optimum type of the pulse width modulation for a predicted duty cycle based on the pulse width modulation generation algorithm.

Abstract: Disclosed is an apparatus for driving a BLDC motor, the apparatus including: a BLDC motor having a single sensing coil therein; a position/speed calculation unit for calculating a current position and a current speed of a rotor by using voltages at both ends of the sensing coil; a control unit for comparing the current speed of the rotor calculated by the position/speed calculation unit with a command speed and then outputting a control signal through a Proportional Integral (PI) control; a motor driving unit for generating a PWM signal based on the current position of the rotor calculated by the position/speed calculation unit and the control signal output by the control unit; and a power device unit for controlling the BLDC motor according to the PWM signal generated by the motor driving unit.

Abstract: A system includes a target speed module and a pulse-width modulation (PWM) control module. The target speed module is configured to provide a first waveform based on a first speed setting for a motor. A start of a first cycle of the first waveform corresponds to at least one of a first current or a first voltage. The PWM control module is configured to shift a phase of the first waveform by a torque angle adjustment value to generate a second waveform. A start of a first cycle of the second waveform corresponds to at least one of a second voltage or a second current. The second voltage is greater than the first voltage, and the second current is greater than the first current. The PWM control module is configured to control the motor based on the second waveform.

Abstract: Proposed is a parallel inverter drive system including includes a plurality of inverter drives connected in parallel with each other, in which each inverter drive includes a switch; a PWM controller connected to the switch for controlling switching operations of the switch device according to a duty cycle signal; and a circulating current suppressor for collecting current information associated with the current of each inverter drive and a summation current, and generating an index according to the collected current information and the desired circulating current quantity. A zero-sequence voltage is generated for each phase of a three-phase voltage command according to the index and the voltage command and the operating mode of the inverter drive, thereby injecting the zero-sequence voltage into the voltage command with a feed-forward configuration so as to fix the voltage command. The PWM controller can generate the duty cycle signal according to the fixed voltage command.

Abstract: According to an aspect of the invention, an apparatus includes: a spindle motor; and circuitry configured to spin up the spindle motor by increasing a command voltage in small steps while monitoring a current flowing through the spindle motor. According to another aspect of the invention, a method includes: spinning up a spindle motor from a stationary state to a target speed using a voltage mode of operation for the spindle motor, wherein the spinning up includes supplying to the spindle motor a series of multiple discrete voltage levels ranging from a first voltage level to a second voltage level; and maintaining the spindle motor at the target speed.

Abstract: A method for pulse width modulation control of a multiple phase drive includes identifying at least one phase from the plurality of phases for the drive as eligible for clamping to one of a plurality of extreme power supply voltages, selecting a phase of the eligible phases having a largest magnitude driving current, determining a first offset signal as a difference between a control signal level for the selected phase and an extreme control signal level corresponding to one of the extreme power supply voltages, limiting a rate of change of the first offset signal to form a second offset signal, and determining a modified control signal for each of the phases for the drive including forming for each of a plurality of the phases a combination of the second offset signal and a control signal level for the phase to determine the modified control signal for the phase.

Abstract: Disclosed herein is a motor control apparatus and a method thereof. A phase error of the reference voltage output corresponding to a time delay caused by digital control may be compensated to stably control a motor, thereby improving the stability of a system. The phase compensation unit may be provided therein to convert a reference voltage of the synchronous coordinate system into a reference voltage of the stationary coordinate system when controlling the high-speed operation of the motor, thereby compensating a phase error of the reference voltage output, and allowing the motor to be operated at a high speed while maintaining its efficiency and reducing a volume of the compressor.

Abstract: A method for pulse width modulation control of a multiple phase drive includes identifying at least one phase from the plurality of phases for the drive as eligible for clamping to one of a plurality of extreme power supply voltages, including excluding from the eligible phases those phases with intermediate control signal levels and excluding phases according to a proximity criterion on the control signal levels. A phase is selected from the eligible phases. An offset signal is determined as a difference between a control signal level for the selected phase and an extreme control signal level associated with one of the plurality of extreme power supply voltages. A modified control signal is determined for each of the phases, by forming a combination of the offset signal and a control signal level for each phase to determine the modified control signal for each phase.

Abstract: A method of determining the average current drawn by an electric motor, the motor comprising a plurality of phases, the method comprising: driving each phase of the motor with cyclic pulse width modulated drive signals having a first state and a second state, and a duty ratio indicative of the ratio of time spent in the first to second states within a cycle, determining the current flowing through each phase at an instant in the cycle; and determining the average current drawn by the motor over at least one cycle by combining the currents flowing through each phase with the duty ratios for each phase. The method may be embodied in a combination of a motor and a drive circuit for the motor, such as can be used in an Electric Power Assisted Steering system.

Abstract: Motor control circuits and associated methods to control an electric motor provide a plurality of drive signal channels at the same phase, resulting in reduced jitter in the rotational speed of the electric motor.

Abstract: A method of estimating stator resistance of an induction motor includes applying voltage pulses through two phase paths of the motor for a plurality of electrical cycles to inject current in the motor, wherein the voltage pulses are applied until rotor flux of the motor is substantially stabilized and measuring stator voltage and stator current in response to the applied voltage pulses for each of the plurality of electrical cycles. The method also includes calculating the stator resistance based upon the measured stator voltages and the stator currents.

Abstract: Methods, system and apparatus are provided for controlling third harmonic voltages when operating a multi-phase machine in an overmodulation region. The multi-phase machine can be, for example, a five-phase machine in a vector controlled motor drive system that includes a five-phase PWM controlled inverter module that drives the five-phase machine. Techniques for overmodulating a reference voltage vector are provided. For example, when the reference voltage vector is determined to be within the overmodulation region, an angle of the reference voltage vector can be modified to generate a reference voltage overmodulation control angle, and a magnitude of the reference voltage vector can be modified, based on the reference voltage overmodulation control angle, to generate a modified magnitude of the reference voltage vector.

Abstract: A method and system for a commutation control circuit are provided. The system includes an integrating voltage counter electrically coupled to an electrical power bus, wherein the integrating voltage counter is configured to integrate over time a voltage signal received from the power bus and to generate a trigger signal when the integrated voltage signal equals a predetermined count. The system also includes a plurality of transistor pairs configured to receive a trigger signal generated by the integrating voltage counter and electrically coupled to respective windings of a motor.

Abstract: A motor drive system includes an inverter that supplies power to a three-phase motor, and a control unit that, when first stopping and then commencing supply of alternating current to three phases of the three-phase motor, switches from first control to third control and then to second control. The first control places switching elements in the inverter in a non-conduction state, the second control is a PWM control of the switching elements, and the third control places and keeps a switching element of each of an upper arm and a lower arm in the conduction state until commencement of the supply of current. The upper arm corresponds to a phase through which current flows in a direction entering the motor upon commencement of the supply, and the lower arm corresponds to a phase through which current flows in a direction exiting the motor upon commencement of the supply.