Abstract: Position samples are stored from an encoder coupled to a permanent magnet electric machine. A data processor determines first changes in position between successive position samples and second changes between successive first changes in position. A data processor determines whether each first change in position is generally increasing, decreasing or constant. A corrective motion factor is applied to each stored position sample based on whether the first change in position is generally increasing or decreasing. The data processor estimates a final rotor angle of the electric machine based on a particular one of the position samples and a corresponding first change in position associated with the particular one of the position samples corresponding to a respective time.

Abstract: A motor drive apparatus includes an inverter which has an upper and lower arms each provided with a plurality of semiconductor switching devices and free-wheeling diodes connected in reverse parallel with respective ones of the plurality of semiconductor switching devices, wherein the semiconductor switching devices are controlled on and off to convert DC to AC, a short-circuiting unit which includes a selector switch between motor phase windings of a synchronous motor, the selector switch being opened and closed under the control of a command, and a dynamic braking control unit which, upon reception of a dynamic braking start command, performs control so as to turn on all of the semiconductor switching devices provided in either one of the upper and lower arms and to turn off all of the semiconductor switching devices provided in the other arm, and thereafter controls the short-circuiting unit so that the selector switch is closed.

Abstract: Embodiments of the present invention permit the optimization of torque control of a permanent magnet machine including obtaining instantaneous terminal voltages of the machine, transforming the instantaneous terminal voltages to a zero direct axis voltage and a non-zero quadrature axis voltage, using a mathematical transformation, regulating the electrical frequency of the permanent-magnet machine such that the zero direct-axis voltage is adjusted to have a value of zero, determining a non-final electrical angle of the permanent-magnet machine by applying an integrator to the regulated electrical frequency of the machine, determining a final electrical angle of the of the machine by integrating the non-final electrical angle and an electrical angle from a previous calculation cycle, and regulating the current vector of the machine such that the current vector is perpendicular to the final electrical angle of the machine, thereby optimizing the torque of the machine.

Abstract: The disclosed device comprises a duty calculator for calculating a duty command value (Dty), a duty limiter for limiting the duty command value (Dty) to a value according to a limit value (L), a current flow monitor for determining that there is an overcurrent if a current value (Idet) flowing through a winding exceeds a predetermined threshold value (Ithr), and a limit value generator for generating the limit value (L). The limit value generator updates the limit value (L) at predetermined time intervals and for a value corresponding to a difference between the threshold value (Ithr) and the current value (Idet) at a time in order to decrease the current value (Idet) during a period in which the overcurrent is determined.

Abstract: A system for determining an initial position of a rotor (9) of a PMSM motor includes a motor controller (2) coupled to a plurality of phase windings of the motor by means of an actuation circuit (3). A processor (12) and an interface circuit (14) are coupled to the processor and the phase windings. The processor determines if the rotor speed is zero, and if so causes the actuation circuit to sequentially apply voltage signals (Vab, Vba, Vac, Vca, Vbc, and Vcb) to the phase windings to produce corresponding phase winding current signals (Iab, Icb, Ica, Iba, Ibc, Iac) in the various phase windings. The phase winding current signals are sensed and digitized. The processor then determines a position of a magnetic flux path associated with the rotor by computing the initial position of the rotor from one of the digitized phase winding current signals associated with the predetermined magnetic flux path.

Abstract: In a multi-phase brushless DC motor, a zero crossing N-bit filter includes a comparator and a phase multiplexer. The phase multiplexer connects each motor phase to each of a positive and a negative input of the comparator, with a switch in each connection to form a switch array. A microprocessor is disposed to operate the switches, and is configured to measure a BEMF for a first phase by opening the switches connecting all other phases to the positive input of the comparator and by opening the switch connecting the first phase being measured to the negative input of said comparator. The comparators output is received by a shift register. The microprocessor is configured to respond to a zero crossing when a majority of bits in the shift register change between high and low.

Abstract: A control device for a motor drive system including an AC motor having a magnet in a rotor, a converter, and an inverter generates a step-up command value for the converter based on a torque command value for the AC motor. The control device determines whether or not to carry out field-weakening control for increasing a current in a direction weakening force of a magnet that is supplied from the inverter to the AC motor, based on the step-up command value and a state of drive of the AC motor. When field-weakening control should be carried out and when an absolute value of the torque command value is smaller than a threshold value, the control device further increases the generated step-up command value. By doing so, an amount of a field-weakening current can be decreased and therefore efficiency of the motor drive system can be improved.

Abstract: A multi-phase rotary machine control apparatus executes calculation processing of an angle error caused by position error in attaching a rotation angle sensor to a motor. The control apparatus sets d-axis and q-axis current command values to zero. A rotary shaft of the rotary machine is rotated externally. The control apparatus detects phase currents caused by a counter-electromotive force, converts phases and outputs voltage command values so that the current detection values become zero. The control apparatus calculates an angle error based on the voltage command values, and stores the angle error as an angle correction value. The control apparatus corrects a detection value of a rotation angle sensor by the stored angle correction value.

Abstract: A drive unit, which can be included in an image forming apparatus with peripherals disposed thereto and use a control method therefore, includes an inner rotor brushless DC motor, a driver, a rotation detector, and a controller. The driver supplies power to drive the brushless DC motor. The rotation detector detects an amount and direction of rotations of an output shaft. The controller controls the rotations of the brushless DC motor and obtains a target drive signal of the brushless DC motor externally and a detection signal from the rotation detector and outputs a signal to the driver. The controller controls a speed of rotation of the brushless DC motor by varying the signal output to the driver based on the target drive signal and the detection signal.

Abstract: A method serves for starting a polyphase electric motor which is operated in a star connection. The method conductively bridges at least one winding part of a phase of the motor and electrically disconnects the bridged winding part, in order in this manner, to supply a higher voltage to the remaining, electrically effective windings, and thus to increase the flow of current and thus the torque.

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 F/B gain control unit computes a first change component by executing torque feedback control based on a torque deviation using a feedback gain that is computed by a F/B gain variable control unit. The F/B gain variable control unit computes one of two different feedback gains that correspond to a “first computation mode” in which the first change component is used as an addition angle and a “second computation mode” in which a value obtained by correcting the first change component by an estimated motor rotation angular velocity is used as the addition angle, respectively. A feedback gain used in the first computation mode is set such that a response at the feedback gain is higher than that at a feedback gain used in the second computation mode.

Abstract: A method for controlling a permanent magnet synchronous motor includes detecting an absolute angular position and using the angular position to calculate a rotational speed of the motor; detecting a voltage of a battery as a power source; calculating a compensated speed from a rotational speed of the permanent magnet synchronous motor based on a torque command, the rotational speed of the permanent magnet synchronous motor, and the battery voltage; generating a d-axis current command and a q-axis current command corresponding to the torque command and the compensated speed; calculating a d-axis voltage command and a q-axis voltage command based on the d-axis current command and the q-axis current command; converting the d-axis voltage command and the q-axis voltage command into three-phase voltage commands based on the detected absolute angular position; and controlling the operation of the permanent magnet synchronous motor based on the three-phase voltage commands.

Abstract: A system for controlling a vehicle, the vehicle including a permanent magnet (PM) synchronous motor, includes a controller. The controller is configured to control the motor with a motor current. In the presence of a predetermined condition, the motor current results in increased winding loss and reduced torque ripple with respect to optimal motor current for minimal winding loss.

Abstract: A surface motor direct-drive sucker-rod screw pump device is driven by a vertical three-phase permanent magnet brush-less DC motor, and comprises a motor controller (6), a rectifying circuit, an inversion circuit, a CPU and a driving circuit. The motor controller (6) is used to adjust the voltage and frequency of the motor by the rectifying circuit, the inversion circuit, the CPU and the driving circuit. Thus, the speed of the motor can vary from zero to the maximum. The device is easy to operate and has a higher efficiency.

Abstract: An apparatus is provided for controlling operation of an electric motor through use of an additional power storage arrangement connected across the DC busses of a motor drive and controlling the speed of the motor. The additional power storage arrangement includes an additional capacitor arrangement and a rate limiting arrangement in a series circuit relationship with one another.

Abstract: A brushless motor driving circuit includes a battery for supplying a power to the brushless motor driving circuit; a driver circuit; a bridge circuit including a plurality of N-channel FETs; a control unit for rotating a brushless motor by switching the bridge circuit through the driver circuit based on a rotor position detection signal; a floating voltage generator for applying a voltage to a first group of the FETs of the bridge circuit; and a converter which is powered from the battery. The converter has an output connected to an input of the floating voltage generator for the first group of the FETs of the bridge circuit and an input of the driver circuit for a second group of the FETs of the bridge circuit to dedicatedly supply a power to gates of the FETs, and the control unit is powered from the battery without using the converter.

Abstract: Certain embodiments are directed to devices, methods, and/or systems that use electrical machines.

Abstract: The Brushless Multiphase Self-Commutation Controller or BMSCC is an adjustable speed drive for reliable, contact-less and stable self-commutation control of electric apparatus, including electric motors and generators. BMSCC transforms multiphase electrical excitation from one frequency to variable frequency that is automatically synchronized to the movement of the electric apparatus without traditional estimation methods of commutation and frequency synthesis using derivatives of electronic, electro-mechanical, and field-oriented-control. Instead, BMSCC comprises an analog electromagnetic computer with synchronous modulation techniques to first establish magnetic energy and then dynamically share packets of magnetic energy between phase windings of a multiphase, position dependent flux, high frequency transformer by direct AC-to-AC conversion without an intermediate DC conversion stage.

Abstract: A method of controlling a brushless motor that includes exciting a winding of the motor in advance of predetermined rotor positions by an advance period. The length of the advance period is defined by a waveform that varies periodically with time. Additionally, a control system that implements the method, and a motor system that incorporates the control system.

Abstract: An observer (404), operating during a time when open loop control (402) is being used to drive a synchronous motor (401), the output of the observer (404) being a signal, E_I_angle, related to the angle between a rotational EMF vector and the current excitation vector, the observer (404) determining the angle by an iterative calculation incorporating a summation term, the summation term summing the variation of the quadrature component of a rotational EMF vector relative to an estimated EMF position vector, and using the angle output of the observer to update the estimate of the rotational EMF position vector. In a further aspect of the invention the observer output signal, E_I_angle, can be used to determine the transition to closed loop control (405), when the observer output signal reaches a value indicating conditions close to pull out conditions.

Abstract: In a method of controlling current in a control circuit of an electric motor, pulse-width modulation (PWM) pulses are applied to a stator of the electric motor, via a plurality of transistors of the control circuit, using a first control mode when a rotational speed of a rotor of the electric motor is within a first range. At least one PWM pulse is applied to the stator, via a subset of the plurality of transistors, using a second control mode when the rotational speed of the rotor is within a second range. When it is determined that the rotational speed of the rotor has changed from being within the second range to being within the first range, additional PWM pulses are applied to the stator such that, for each of the plurality of transistors, a current through the transistor does not exceed a maximum current capacity of the transistor.

Abstract: A method for controlling a discharge pump of a household appliance, including starting a synchronous electric motor that actuates said discharge pump until the synchronism condition is reached, and driving said synchronous electric motor at a steady state through phase control by varying the firing angle (?). In driving said synchronous motor at steady state through phase control, said firing angle (?) is feedback controlled to cancel the phase difference between the mid-point of a zero current plateau of a function of the phase current fed to the electric motor and the zero-crossing point of a counter electromotive force signal (fcem) relative to the same phase. In feedback controlling the firing angle (?), the synchronous electric motor is switched off if the required firing angle (?) exceeds a maximum threshold (?lim), which may result from the operation of the discharge pump in air-water conditions.

Abstract: The invention relates to methods and devices for monitoring and correcting a sensorless rotor position detection in permanently excited motors, comprising a control device and a current converter. The invention is especially characterised in that the ambiguity of the rotor position determined from the inductance ratios of the motor, in permanently excited motors, can be resolved in a simple manner without a sensor, and a defectively determined angle can be corrected as required. To this end, during the operation of the motor, the rotor position is detected by means of an inductance-based detection device. Furthermore, the rotor position is monitored in relation to the ambiguity of the inductance-based signals by means of a monitoring/correcting device, and where necessary, an occurring angle error corrected, the currents in the motor being modified.

Abstract: A first inverter and a second inverter supply two coil sets forming a three-phase motor with AC voltages, which are the same in amplitude but shifted by 30° in phase. Current detectors detect phase currents supplied from the inverters to the coil sets. Temperature estimation sections estimate temperatures of the inverters or the coil sets based on an integration value of the phase current detection values. A current command value limitation section limits upper limits of current command values of both coil sets based on the estimated temperatures Tm1 and Tm2. Thus, the inverters and the coils sets are protected from overheating without increasing torque ripple.

Abstract: A back electromotive force (EMF) detector for a motor is disclosed. The back EMF detector includes an upper switch, a lower switch, a current sensing resistor and a first to third resistance providers. The upper and lower switches are controlled by a first and a second control signal respectively. The current sensing resistor coupled between the lower switch and a reference ground voltage. A first terminal of the first resistance provider coupled to the upper switch, and a back EMF detection result is generated at a second terminal of the first resistance provider. The second resistance provider coupled between the reference ground voltage and the first resistance provider. The third resistance provider is coupled between the coupled terminal of the first and second resistance provider and the lower switch. Wherein, the first to the third resistance providers are determined by at least one characteristic parameter of the motor.

Abstract: A control apparatus is for use in a power conversion system including a DC/AC converter circuit connected to an electric rotating machine at output terminals thereof and to a DC power source at input terminals thereof through a switching means, a capacitor being connected across the input terminals of the DC/AC converter circuit. The control apparatus includes a current supply means configured to perform current supply control to supply a current to the electric rotating machine in order to discharge the capacitor by manipulating the DC/AC converter circuit in a state where the switching means is set open, and a speed lowering means configured to apply a brake force to a rotating shaft of the electric rotating machine to reduce a rotational speed of the electric rotating machine prior to the current supply control being performed by the current supply means if the rotational speed exceeds a specified speed.

Abstract: In a method and a device for identifying a reversing operation in an electric actuating unit of a vehicle, once a trapped object is detected, the rotational direction of the electromotive drive is commutated. Sequential pulse interval counter values, derived from a sensor system or data derived from the values is or are written to a ring buffer store and compared with pre-defined reference data patterns. If a match is found, the counter reading of the position counter is corrected in accordance with the pre-defined reference data pattern. This ensures that the counter reading of the position counter is correct even after a reversing operation.

Abstract: A control apparatus for an electric motor provided with a rotator having a permanent magnet and with a stator for generating a rotating magnetic field by an applied voltage and revolving the rotator includes: a rectangular wave inverter that applies a rectangular wave voltage onto the stator of the electric motor to drive the electric motor; a voltage converting section that raises or lowers an output voltage of a direct-current power supply and applies the voltage onto the rectangular wave inverter; an electrical angle acquiring section that acquires an electrical angle of the rotator of the electric motor; and an output voltage command generating section that generates a command for instructing the voltage converting section to output an electrical-angle synchronized voltage whose amplitude ripples in synchronization with a change of the electrical angle of the rotator acquired by the electrical angle acquiring section.

Abstract: A method for calculating a motor constant of a permanent magnet type synchronous motor according to the present invention includes: a voltage applying step of applying a voltage obtained by compositing a DC component and an AC component to a permanent magnet type synchronous motor while varying a frequency of the AC component; a current detecting step of detecting a motor current flowing according to the applied voltage; a phase difference calculating step of calculating a difference in phase between the AC component of the applied voltage and an AC component of the motor current; and a motor constant calculating step of calculating a motor constant of the permanent magnet type synchronous motor. In addition, in the motor constant calculating step, the motor constant is calculated based on the applied voltage and the motor current when the difference in phase becomes nearly 45 degrees.

Abstract: The invention relates to an electronically commutated electric motor. The electric motor comprises a stator, and a rotor, in particular a permanent-magnetic rotor. The electric motor further comprises a control unit connected to the stator. The control unit is designed to actuate the stator such that the stator can generate a magnetic rotating field for rotationally moving the rotor. According to the invention, the control unit of the electric motor is provided with a power output stage having semiconductor switches. Subject to the low-resistance, or short-circuited, semiconductor switch of the power output stage, in particular as a result of defect, the control unit is designed to actuate the stator for generating the rotating field such that during a complete rotor revolution, the rotor can provide a mechanical output, or in the operational mode, a braking torque of the electric motor caused by the defect is reduced, or completely neutralized, by the low-resistance, or short-circuited, semiconductor switch.

Abstract: A rotary electric machine system includes: a stator that has multi-phase stator coils and that generates stator magnetomotive forces based on respective stator currents having different phases supplied to the multi-phase stator coils; a rotor on which rotor coils are wound such that magnetic poles are formed by rotor currents generated in response to the stator magnetomotive forces generated by the stator; a regulating unit that regulates a flow direction of each of the rotor currents to one direction to thereby regulate a polarity of each of the magnetic poles; and a control unit that controls currents supplied to the stator coils on the basis of a target torque. The control unit superimposes a pulse on the stator currents to adjust the ratio of each of the stator currents and each of the rotor currents so as to minimize a copper loss in the stator and the rotor.

Abstract: A power converting apparatus including a power converter that converts a DC voltage into an AC voltage and applies the AC voltage to an AC rotating machine and a control unit that controls the power converter based on an operation command from the outside is provided. The power converting apparatus includes: a first calculating unit that calculates and outputs, from a d-axis current detection value and a q-axis current detection value detected by the AC rotating machine and current command values based on the operation command, first voltage command values to the power converter, magnetic fluxes of the AC rotating machine, and an angular frequency; and a second calculating unit that sets, as an initial value, at least one of the magnetic fluxes and the angular frequency input from the first calculating unit and calculates and outputs second voltage command value to the power converter and an angular frequency.

Abstract: A drive and control circuit for motor system and the method thereof are disclosed. The motor system could be applied in a cooling device, wherein the motor system comprises a rotor, a coil and a bridge circuit. The drive and control circuit comprises a control unit, a state detecting circuit, a load determining circuit, and a startup setting circuit. The startup setting circuit makes the motor run with the maximum torque, thus to make the motor system start up easily and quickly. The load determining circuit detects the load of the motor system, thus to generate a load determining signal to determine the speed of the motor system. The control unit could be realized with few components so as to save the costs.

Abstract: A DC voltage value from a DC voltage detection section is input directly to a voltage correction section without passing through a compensator or a filter. Therefore, even when rapid voltage change occurs, such as short power interruptions, instantaneous voltage drop and return from instantaneous voltage drop, the voltage correction section can quickly perform the correction operation in response to the rapid voltage change. Since the amount of link resonance compensation is limited by the limitation section to a certain range, it is possible to prevent the amount of link resonance compensation from fluctuating excessively upon rapid voltage change. Since the amount of link resonance compensation which is limited by the limitation section to a certain range is input to one compensator that has an appropriate control band, among all control calculation sections, the response does not have to be unnecessarily fast, thus realizing a stable control.

Abstract: Apparatus and associated systems and methods may relate to a process for supplying unidirectional current to a load, controlling a reverse electromotive force (REMF), capturing inductive energy from the load, and supplying the captured inductive energy to the load. In an illustrative example, an operating cycle may include a sequence of operations. First, inductive energy captured from the load on a previous cycle may be supplied to the load. Second, energy may be supplied to the load from an external power source. Third, a REMF voltage may be substantially controlled upon disconnecting the power source from the load. Fourth, the load current may be brought to zero by capturing the inductive energy for use on a subsequent cycle. In some embodiments, a single power stage may supply a DC inductive load, or a pair of power stages may be operated to supply bidirectional current to an AC load.

Abstract: A controller for an electric actuator includes a reference model that generates position and speed reference signals in response to a position command signal and employs a feed forward model that accounts for dynamic loading of the electric actuator. The feed forward model receives the position and speed reference signals provided by the reference model, and in response generates feed forward signals that account for mechanical characteristics of the electric actuator.

Abstract: A sensorless permanent magnet motor system that prevents negative torque caused by back EMF. The system determines the position of the rotating permanent magnet by monitoring back EMF generated on an inactive coil of the motor system. A snubber circuit is used to prevent the back EMF from causing negative torque on the motor. The voltage of back EMF used to power a logic circuit, such as a microcontroller, that controls the operation of the motor. The microcontroller controls the operation of the motor by detecting back EMF and is also partially powered by the back EMF.

Abstract: A motor control apparatus includes a phase sensing circuit, a current sensing circuit, a controller and a driving circuit. The driving circuit receives a first driving signal and then controls a phase switching state of the magnetic pole of the motor so as to drive the motor in accordance with the first driving signal. The phase sensing circuit detects the phase switching state of the magnetic pole to generate and output a phase switching signal to the controller during the motor is operating. The current sensing circuit detects a current flowing through the motor to generate and output a current phase signal to the controller. The controller compares a phase difference between the phase switching signal and the current phase signal to generate and output a second driving signal to the driving circuit. The driving circuit controls the phase switching state of the magnetic pole for driving the motor in accordance with the second driving signal.

Abstract: Phase correction unit (25) for outputting a commutation signal for switching a winding that allows a current to flow to brushless DC motor (4) and drive unit (16) for outputting a drive signal indicating supplying timing of electric power supplied to brushless DC motor (4) by inverter (3) based on the commutation signal output from phase correction unit (25) are provided so as to maintain a predetermined relation between a phase of a current flowing to a predetermined winding of brushless DC motor (4) and a phase of a voltage. Since brushless DC motor (4) is driven by a signal for holding the predetermined relation between the phase of the current and the phase of the voltage, the stability of drive under high-speed and high-load conditions is enhanced and a drive range is extended.

Abstract: A second q-axis current command value, which is set by a q-axis current command value setting unit when an alternating-current power source fails at the time of driving of a synchronous motor, and a second d-axis current command value, which is set by a d-axis current command value setting unit when the alternating-current power source fails at the time of the driving of the synchronous motor, are set so that an absolute value of power per unit time of the synchronous motor is equal to loss per unit time of the synchronous motor.

Abstract: The present invention relates to a drive apparatus and drive method for switching an energization mode when a voltage of a non-energized phase of a brushless motor crosses a threshold. In threshold learning, first, the brushless motor is stopped at an initial position. The brushless motor is then rotated by performing phase energization based on the energization mode from the stopped state. The voltage of the non-energized phase at an angular position of switching the energization mode is detected from a maximum value or a minimum value of the voltage of the non-energized phase during the rotation, and the threshold is learned based on the detected voltage. Alternatively, the brushless motor is positioned at the angular position of switching the energization mode by maintaining one energization mode, and then the energization mode is switched to the next energization mode.

Abstract: Disclosed is a current source inverter device which controls the power factor in an arbitrarily configurable manner without a magnetic pole position detector. The device is provided with a current source inverter; a motor supplied with alternating current power from the current source inverter; and a control means which detects the terminal voltage of the motor, calculates the motor's internal induced voltage and the motor current that flows in the motor based on the detected terminal voltage, and controls the current source inverter. The control means calculates the phase difference (?c) between the terminal voltage and the motor current, the phase difference (?x) between the motor current and the internal induced voltage, and the phase difference (?v) between the terminal voltage and the internal induced voltage.

Abstract: An AC electric motor includes an annular A-phase winding WA wound in the circumferential direction of a stator, a stator pole group SPGA configured to generate magnetic flux ?A to interlink with the A-phase winding WA, an annular B-phase winding WB wound in the circumferential direction, and a stator pole group SPGB configured to generate magnetic flux ?B to interlink with the B-phase winding WB. The motor additionally includes a third stator pole group SPGC, N and S magnetic poles of the rotor, and X magnetic poles, which serve as third rotor poles, showing magnetic characteristics between the N and S magnetic poles of the rotor. DC currents are supplied to the A-phase and B-phase windings WA and WB to generate rotational torque.

Abstract: A motor for a synchronous electric machine includes a first inverter configured to provide alternating current power at a first plurality of phases. Also included is a second inverter configured to provide alternating current power at a second plurality of phases. Further included is a first stator winding and a second stator winding each in operable communication with the first inverter and the second inverter and configured to operate synchronously at a first phase, a second phase and a third phase. Yet further included is a first interphase transformer for receiving one of the first plurality of phases and one of the second plurality of phases for communicating a pair of simultaneous, matching voltage outputs to the first stator winding and the second stator winding for reducing a stress imposed on a rotor.

Abstract: A system and method for determining the start position of a motor. According to an embodiment, a voltage pulse signal may be generated across a pair of windings in a motor. A current response signal will be generated and based upon the position of the motor, the response signal will be greater in one pulse signal polarity as opposed to an opposite pulse signal polarity. The response signal may be compared for s specific duration of time or until a specific integration threshold has been reached. Further, the response signal may be converted into a digital signal such that a sigma-delta circuit may smooth out glitches more easily. In this manner, the position of the motor may be determined to within 60 electrical degrees during a startup.

Abstract: A motor control device that performs vector control to control a q-axis current and a d-axis current of a permanent magnet synchronous motor independent from each other. The motor control device includes a q-axis current and d-axis current detection unit configured to detect a q-axis current and a d-axis current of a permanent magnet synchronous motor, a q-axis current command value generation unit configured to generate a q-axis current command value, a d-axis current command value generation unit configured to generate a d-axis current command value, in which an amount of rise in the temperature of permanent magnets in a steady state of the permanent magnet synchronous motor is a minimum, and a drive unit configured to drive the permanent magnet synchronous motor.

Abstract: A control method for a sensor-less, brushless, three-phase DC motor. The stator coil in the electromagnets inside the motor may be used as the inductive element through which a voltage regulator can regulate the current as a means of regulating the output voltage. The value of the control signal provided to the drivers controlling power to the coils may be calculated based on at least the rail voltage, as measured in real time. This allows for a wide variation of input voltages, while maintaining a relatively constant output power to the motor. In general, by taking into account the value of the rail voltage when determining the final value of the control signal that is applied to the stator coils, the maximum current through the stator coils may be scaled to the same magnitude current that would be expected to flow through the coils if the rail voltage were the rated (nominal) fan/motor voltage, even when the actual rail voltage is different, e.g. higher than the rated fan/motor voltage.

Abstract: A current control module generates a voltage request based on a d-axis current (Idr) demand. A switching control module controls a motor based on the voltage request and generates an out-of-volts (OOV) signal based on a comparison of the voltage request and an available voltage. An Idr injection module generates the Idr demand based on a direct current (DC) bus voltage, a rotational speed, and a demanded torque and selectively applies a first adjustment to the Idr demand. The Idr injection module identifies whether an improvement resulted from the first adjustment, wherein the improvement is identified based on at least one of (i) a measured current of the motor and (ii) the OOV signal. The Idr injection module selectively applies a second adjustment to the Idr demand based on whether the improvement is identified.

Abstract: A control system for an actuator including a straight slot direct current motor comprises a position sensor for measuring the angular position (?) of the motor and a current sensor for measuring the current strength (Im) in the motor, but not having a sensor for measuring the angular rotation speed of the motor.