Abstract: A system and method of restarting a switched reluctance motor after a cycling of power provided to the motor is provided that includes receiving at the motor a power-off signal followed by a power-on signal, determining a rotational speed of a rotor, and energizing a stator only when the rotational speed of the rotor is determined to be less than a threshold speed.

Abstract: In order to control the position of a mobile body without using a position detector, a magnetic pole position of a rotor of a synchronous motor is estimated based on electrical quantities in relation to electric power supplied to the synchronous motor and then the mobile body position is estimated based on the estimated magnetic pole position.

Abstract: A failure monitor designed to monitor a failure in operation of a motor drive control system. The system works to drive a motor-driven member through an output shaft and an electric motor and includes an output shaft angular position sensor for determining an angular position of the output shaft and an encoder for determining an angular position of the motor for use in controlling the motor. The system works to discriminate among failures in operation of the output shaft angular position sensor and the encoder and another type of a failure using outputs of the sensors.

Abstract: A method and apparatus for improving speed measurement quality in systems having multi-pole machines is taught. The method compensates for pole misalignment by computing speed based upon moving average techniques. In one embodiment, a moving average speed averaged over a complete interval of rotation is determined, based upon measurements of one or more magnetic pole position sensors for magnetic pole location. In another embodiment, a time interval between two poles is averaged over one or more rotational periods, and the average time interval is used to determine the moving average speed. Computation of the moving average speed reduces errors in speed measurements due to pole misalignment and may provide for smaller control adjustment times for controlling motor speed variability. In one embodiment, the speed measurement system includes a multi-pole rotor, and a controller having a capture timer and a buffer.

Abstract: An AC servo drive without current sensor includes a PI (proportional integration) controller, at least two first-order controllers (polar point and zero point), a decoupling compensator, a coordinate converter, a pulse width modulator, a counter and a speed estimator. The AC servo drive is connected with a servomotor to form an AC servo module. The servomotor comprises an encoder receiving a current command signal from the servo module to function as input current command signal or the d, q axes PI controller and the decoupling compensator. The voltage command signal generated by the d, q axes PI controller and the signal generated by the decoupling compensator form a control signal and input to the coordinate converter. The signal output from the coordinate converter is processed by PWM controller to control the servomotor. Therefore, the deterioration of servo motor control caused by temperature drift and cost can be solved.

Abstract: A vector-control system and method of a “sensorless” type for electric drives with a.c. motors is based upon generation of an oscillating magnetic field and upon measurement of the deviation, with respect to said oscillating field, of the flux generated thereby on account of anisotropy, whether natural or induced, of the magnetic structure of the machine.

Abstract: Synchronous motor controlling apparatus and method controls power applied to minimize or eliminate speed variations of a synchronous motor due to variations in load imposed the motor. The rotational position of a rotor of the synchronous motor based on the input terminal voltages and currents to the synchronous motor, and the power applied to the motor is adjusted accordingly. Higher harmonics of the input voltages and currents may also be used to detect the position of the rotor. In addition, the apparatus and method also accounts for the varying speed command inputs.

Abstract: Disclosed is a method for controlling the firing angle of a signle-phase AC powered electric motor which is triggered by means of at least one locking electronic switch, especially a triac (T1 and T4) located between the distribution voltage (UV) and at least one motor winding (A, B). According to said method, intervals are defined within which the triacs (T2 to T4) are to be fired according to the curve of the distribution voltage (UV) and the voltage (UEMK) induced in the respective winding in order to allow the motor to start as quickly and smoothly as possible and run quietly and at high efficiency.

Abstract: A brushless motor drive device has a signal synthesizing circuit for converting a plurality of sensing signals into a plurality of drive signals so as to determine an amplitude of each of the drive signals in accordance with a current error signal. The sensing signals are generated by a sensing circuit in response to variations in a magnetic field of a brushless multi-phase motor. The current error signal is representative of a difference between a current command signal and a motor drive current. The signal synthesizing circuit is characterized by including a calibrating circuit for adjusting the current error signal in accordance with an amplitude of any of the sensing signals. The calibrating circuit includes a differential amplifying circuit, a rectifying circuit, a filtering circuit, and a dividing circuit.

Abstract: A lead-angle control device according to the present invention includes: a space voltage vector controller calculating effective vector application times necessary for obtaining output voltage vectors of an inverter from stationary-coordinate-system instruction voltage components; a lead-angle compensator comparing the sum of the effective vector application times with a sampling period, and generating lead-angle compensation values; a speed controller generating an instruction current for compensating an error caused by a difference between an instruction speed and a current speed; an instruction current generator which generates a rotating-coordinate-system instruction current component by extracting a lead-angle component at a point where maximum torque-per-ampere can be obtained from the magnitude of the instruction current and performing a mathematical calculation on the magnitude of the instruction current and a lead-angle component; and an instruction voltage generator generating a stationary-coordinat

Abstract: An influence resulting from double saliency of an electric motor, i.e., an influence of a deviation of the axis of an alternating current due to a rotor magnetic pole position ? on the estimation of a magnetic pole position, is eliminated, and, in particular, the magnetic pole position of a double saliency electric motor can be estimated with high precision.

Abstract: In a motor-driven shift position switching device, when the difference between a target position and the rotation position of a rotor has become smaller than a prescribed value in a motor feedback control, a transition is made to a deceleration control. A phase lead correction amount for correcting the phase lead of the current supply phase with respect to the rotor rotation phase is set in accordance with the rotor rotation speed. Thus, proper braking force suitable for the rotor rotation speed is exerted on the rotor and the rotor can be decelerated smoothly as it approaches the target position. Further, in the period when the current supply to the motor is kept off, the shift position switching determination ranges are set wider than in the period when the current supply to the motor is on.

Abstract: A method for controlling a voltage mode controlled electric machine comprising: receiving a torque value representative of a desired torque; obtaining a speed value indicative of a rotational velocity of the electric machine; acquiring a phase advance value indicative of a desired phase advance angle; generating a voltage command responsive to the torque value, the position value; the generating is responsive to the torque value, the speed value, and the phase advance value.

Abstract: It is an object of the invention to provide an apparatus for estimating a magnetic pole position of a motor in which the amplitudes of high-frequency currents can be adjusted. In the invention, a controlling apparatus for driving a motor (1-1) by a voltage source PWM inverter (1-2), and controlling a torque and speed, or torque, speed, and position of the motor has: means for switching over first means for producing an arbitrary phase difference in PWM carrier signals between respective two phases such as UV, VW, or WU of three or UVW phases, and second means for causing the phase difference between two phases such as V, VW, or WU of three or UVW phases to become zero; means for extracting high-frequency currents in a same frequency band as carrier signals generated by it, from estimated currents; and means (1-4) for estimating a magnetic pole position by using the extracted high-frequency currents.

Abstract: A drive method for a brushless motor and a drive control apparatus therefor, in which control parameters are calculated by motor current control means (74 in FIG. 2) in accordance with the deviation between a target motor current value and an actual motor current value, a manipulated variable is computed by phase control means (76) on the basis of the calculated control parameters, an advance angle magnitude is computed from the relationship between a manipulated variable and an advance angle magnitude as designed and created beforehand, on the basis of the computed manipulated variable, and the value of the conduction phase angle of a drive circuit (72) as set on the basis of a motor current signal is corrected with the information of the computed advance angle magnitude.

Abstract: In the invention, a PWM signal is formed at a frequency of a reference pulse signal, the PWM signal which has a pulse width being changed according to a frequency difference between an FG pulse signal for detecting a speed of a brushless motor and the reference pulse signal of a target speed, an output signal for PWM control is formed by an N-fold frequency of the PWM signal, the output signal for PWM control in which a pulse having the divided pulse width is arranged in each N-divided period, the N-divided period in which each one period of the PWM signal is divided by N, and electric power supply to a coil of each phase of the brushless motor is turned on and off at intervals shorter than that of the output signal control without increasing the frequency of the reference pulse signal.

Abstract: A sensorless motor drive apparatus and a method for protecting and controlling the same. The sensorless motor drive apparatus includes a unit for determining the presence or absence of a position estimation error of a rotor contained in a motor using a current value applied to the motor and a position estimation angle of the rotor. Therefore, the sensorless motor drive apparatus determines the presence or absence of the position estimation error of the rotor without using a sensor, so that it reduces production costs, prevents the motor from generating a faulty operation, and prevents a compressor including the motor from being damaged.

Abstract: Methods and apparatus provide for commutating windings of a polyphase machine such that electromagnetic fields of stator and rotor phases of the polyphase machine produce at least one of motoring and generating torque, wherein the controller is operable to automatically vary at least one of a lead angle measured between the electromagnetic fields of the stator and rotor phases and rotor excitation parameters as a function of a rotational speed of the polyphase machine.

Abstract: A system and method are provided for controlling a three-phased permanent magnet electric motor terminal voltages in relation to both changes in speed and torque of the permanent magnet electric motor, whereby phase currents are first rotated from a stationary frame to two decoupled current components in a rotor synchronous frame, which enable to derive a voltage along a quadrature axis and a voltage along a direct axis thereof, before rotating back the quadrature and direct axis voltages from the rotor synchronous frame to the stationary frame to yield the permanent magnet electric motor terminal voltages.

Abstract: A motor driver drives a motor composed of a rotor and plural-phase windings that generate a magnetic field for rotating the rotor, including: a plurality of transistors that operate as switches for supplying current to the windings; a position detector operable to detect a rotational position of the rotor, based on a terminal voltage of each winding; and a switching controller operable to have performed a switching method to turn the transistors to an ON state or to an OFF state for controlling the rotor at the predetermined speed by means of the position detector, wherein the switching controller further controls so as to force each of the transistors into the OFF state for a predetermined duration in a predetermined cycle, and the position detector detects only while the switching controller forcedly keeps the transistor in the OFF state.

Abstract: A motor driving apparatus includes a comparator, a threshold controller, a position determining unit, a phase-switching controller, and a current output unit. While the rotor is stopped, the phase-switching controller supplies a predetermined phase of winding with a current pulse having a predetermined pulse width so as not to cause the rotor to react and operate, in order to determine the initial position of the rotor. The position determining unit determines an initial position of the rotor based on the result of comparison between the induced voltage generated in a non-conduction phase by the current pulse and the threshold. The phase-switching controller performs energization or commutation according to the determined initial position of the rotor to start up the motor.

Abstract: A sensorless brushless motor controls a rotational speed of a rotor by sequentially energizing a plurality of excitation coils constituting a stator in accordance with a logical product between an energizing timing signal generated on the basis of a back electromotive forces and a pulse width modulation signal to control a pulse width of the pulse width modulation signal, wherein back EMF induced in the plurality of excitation coils are respectively supplied to first and second comparator circuits each having a different reference voltage, respective output signals from the first and the second comparator circuits are sampled simultaneously at a predetermined cycle, and the energizing timing signal is generated at the time of the respective output signals from the first and the second comparator circuits becoming a high-level or a low-level during the sampling. The accuracy of rotor position detection by using a back EMF is improved.

Abstract: A switched reluctance machine system includes a stator, a rotor situated to rotate relative to the stator and a plurality of phase windings situated in the stator. A power supply is connected to the phase windings via power converter and a controller outputs control signals to the power converter to selectively apply power to the phase windings. The controller receives feedback signals from the phase windings that provide phase current information to the controller. The controller is programmed to analyze the phase current information and control the power converter to inject diagnostic pulses into any of the phase windings in which current in the phase winding is below a predetermined level. The rotor position is determined based on detected characteristics of the diagnostic pulses, and the characteristics may be weighted, for example, in response to an estimated position of the diagnostic pulses.

Abstract: A method of controlling a power converter (20) of a motor drive system (10)controls the power converter (20) during a first operating mode by applying a current control scheme, which sets power converter commands to control torque current flowing from the power converter (20) to the motor (30) to achieve desired motor speed; and initiates a second operating mode when power supply to the power converter (20) is interrupted. The second operating mode includes controlling negative torque current between the power converter (20) and the motor (30) so that mechanical energy from the motor (30) charges an element (58) on a power supply side of the power converter (20). The first operating mode is resumed when the input power recovers. Torque current between the power converter (20) and the motor (30) is also controlled to limit a maximum transient DC bus voltage.

Abstract: An apparatus for use with a signal generator and a motor controller includes a velocity compensator, an adjustor, and a velocity regulator. The signal generator provides a reference velocity signal, and the motor controller receives an output signal and uses the output signal to control a torque input signal applied to the motor. The velocity compensator is operable to receive the reference velocity signal, determine a derivative of the reference velocity signal, and generate a velocity compensation signal based on the derivative. The adjustor is operable to adjust the reference velocity signal as a function of the velocity compensation signal. The velocity regulator is operable to compare the adjusted reference velocity signal to a feedback velocity signal and generate the output signal received by the motor controller for adjusting the torque input signal based on the comparison.

Abstract: According to the invention, in a method for determining the angular position of a rotor, a reference voltage is set in a calibration phase, such that when the rotor, rotating at a calibration speed, passes through a particular detection position, said voltage is the same as the electromotive force induced in the one winding coil. In a subsequent measuring phase the reference voltage is updated to a value (UR) which is equal to the product of the voltage value set in the calibration phase and the ratio of the instantaneous motor rotational speed to the calibration rotational speed. The angular position of the rotor (?1) at which the electromotive force corresponds to the updated reference voltage is thus identified as the detection position.

Abstract: A method for sensorless estimation of rotor speed and position of a permanent magnet synchronous machine the method comprising the steps of calculating first stator flux vector estimate ({circumflex over (?)}d,i+j{circumflex over (?)}q,i) using the flux model and measured stator currents, calculating second stator flux vector estimate ({circumflex over (?)}d,u+j{circumflex over (?)}q,u) using the voltage model and measured stator voltages, comparing the directions of the first and second flux vectors to achieve a first error signal (F?), using speed adaptation to achieve estimates for the rotor angular speed ({circumflex over (?)}m) and angular position ({circumflex over (?)}m) from the first error signal (F?), injecting a known voltage signal (uc) to the stator voltage, detecting a current signal (iqc) from the stator current to form a second error (?) signal, which is dependent on the estimation error of the rotor position, augmenting the voltage model by the second error signal (?) to keep the first and se

Abstract: A controller (72) for a switched reluctance machine (20) implements a model of at least one active phase representing dynamic magnetic machine characteristics. The controller (72) determines machine control signals based on rotational position obtained by numerically solving the model with measured machine operating parameters. The model may be implemented as the sum of orthogonal functions relating active phase voltage and current with constants derived from phase inductance to obtain the rotor angle.

Abstract: A startup control method of a BLDC motor is disclosed. The method can control the BLDC motor to prevent the generation of a transient current such that the vibration of the BLDC motor can be reduced at the startup stage and perform a stable conversion into a sensorless operation mode such that the startup failure rate of the BLDC motor can be reduced. The startup control method includes commutating a current applied to stator windings according to a rotor position. The method of operating the BLDC motor includes a rotor position that is forcibly aligned and so that phase commutation is performed, a back-electromotive force (back-emf) is detected from a lead voltage of a phase of a voltage which is not applied thereto after performing phase commutation and a determination is performed as to whether the detected back-emf is in a rising interval.

Abstract: The present invention relates to a method of controlling a power converter (20) of a synchronous machine system (10), the method comprising sampling phase-current values between the power converter (20) and the synchronous machine (30); selecting a reference frame; regulating a current vector to align with the selected reference frame, the selected reference frame having a direct-axis component and a quadrature-axis component; estimating rotor speed and position as a function of instantaneous power; adjusting the selected reference frame, based on estimated rotor position, to synchronize the selected reference frame with a magnetic axis of the rotor, thereby generating a synchronized floating frame; and applying the synchronized floating frame to control the power converter (20). The present invention also related to a power converter controlling apparatus (100) for controlling a power converter (20) of a synchronous machine system (10) without use of a machine position sensor.

Abstract: A method for determining a rotor position angle of a synchronous machine, the method comprising the steps of determining inductances (LA, LB, LC) of the synchronous machine in stator phase directions; generating an inductance vector (L) on the basis of the determined inductances (LA, LB, LC); and determining the rotor position angle (qr) on the basis of the determined inductance vector angle.

Abstract: A circuit (10) for a fan motor comprises a driver circuit (12) having an FG terminal which is able to output a first signal carrying speed information of the fan motor, a photo coupler (142) connected to the FG terminal to receive the first signal, the first signal being convertible by the photo coupler to a second signal carrying the same speed information, and a speed detection circuit (16) connected to the photo coupler to recognize the speed information by detecting the second signal.

Abstract: An apparatus is provided to control a three-phase AC motor and comprises an inverter and a controller. The inverter powers the motor in response to a three-phase PWM command. The control circuit controls the inverter based on two modulation techniques selectively switched from one the other depending on information indicative of an operation state of the motor. One modulation technique gives the PWM command a first two-phase modulation allowing each phase voltage to be fixed at a predetermined voltage level in turn at intervals of an electrical angle of 2?/3. The other modulation technique gives the PWM command a second two-phase modulation allowing each phase voltage to be fixed at a predetermined voltage in turn at intervals of an electrical angle of ?/3. The switchover can be made between the two-phase and three-phase modulations or can be made with consideration of temperature at switching elements.

Abstract: An apparatus is provided for controlling a synchronous motor. The apparatus comprises a first calculator calculating a voltage characteristic showing a characteristic of voltages to be applied to armature coils of a stator and a producer producing a command signal to provide the armature coils with the phase currents on the basis of the voltage characteristic. The apparatus still comprises a current detector detecting a signal depending on an amplitude of at least one of the phase currents, a second calculator calculating a rate of changes in a current amount indicating amplitudes of the phase currents, by using the signal from the current detector, and a feed-back member feed-backing the rate of changes in the current amount into the calculation of the voltage characteristic.

Abstract: Disclosed is an apparatus and method for controlling a reciprocating compressor capable of inexpensively and exactly controlling a position of a piston in a cylinder, by which a top clearance is minimized according to the information of a phase difference between a square wave of a piston stroke and a square wave of a current supplied to the compressor. The apparatus comprises a driving section for driving the reciprocating compressor by varying an angle or ignition in response to a control signal; a current phase detecting section for outputting a square wave corresponding to the detected current supplied to the compressor; a stroke phase detecting section for outputting a square wave corresponding to a stroke of the compressor; and a control section for controlling the angle of ignition of the driving section according to the phase difference between the square wave produced from the current phase detecting section and the square wave produced from the stroke phase detecting section.

Abstract: A control system for an electric machine includes a flux weakening module, which includes a voltage magnitude calculator that receives d-axis and q-axis command voltages and that generates a voltage magnitude. An error circuit compares the voltage magnitude to a reference voltage and generates an error signal. A controller receives the error signal and generates a feedback flux correction signal. A limiter limits the feedback flux correction signal to a predetermined flux value and generates a limited feedback flux correction signal. A feedforward stator flux generating circuit generates a feedforward stator flux signal. A summing circuit sums the feedforward stator flux signal and the limited feedback flux correction signal to generate a final stator flux command.

Abstract: A motor control apparatus capable of easily and reliably determining the completion of starting of a synchronous motor and not requiring an arithmetic unit having high processing ability for the determination. When an operation command including a predetermined target rotation speed is received in a state where the motor is at rest, PWM signals are created on the basis of a starting voltage set by a starting voltage setting section and a starting phase set by a starting phase setting section, whereby the motor is started. After the start of the motor, a starting rotation speed setting section makes the processing to increase the starting rotation speed. When the starting rotation speed reaches a predetermined value smaller than the target rotation speed, it is determined that the starting is completed, and a shift is made from starting operation to normal operation.

Abstract: A stepping motor driver according to the present invention includes a torque component current calculating means for calculating a torque component current from phase currents and a rotor rotation angle, an absolute value converting means for obtaining an absolute value of the torque component current, a high speed-response judging means adapted for outputting a first control signal when a speed deviation between a command speed and a rotor speed is not more than a reference level, and outputting a second control signal when the speed deviation exceeds the reference level, and a current command outputting means adapted for outputting a current command according to the absolute value of the torque component current when the first control signal is outputted, and outputting a maximum current command value as the current command when the second control signal is outputted.

Abstract: In a motor-driven shift position switching device, when the difference between a target position and the rotation position of a rotor has become smaller than a prescribed value in a motor feedback control, a transition is made to a deceleration control. A phase lead correction amount for correcting the phase lead of the current supply phase with respect to the rotor rotation phase is set in accordance with the rotor rotation speed. Thus, proper braking force suitable for the rotor rotation speed is exerted on the rotor and the rotor can be decelerated smoothly as it approaches the target position. Further, in the period when the current supply to the motor is kept off, the shift position switching determination ranges are set wider than in the period when the current supply to the motor is on.

Abstract: A system and method is provided for starting a prime mover coupled to a synchronous starter/generator. The system includes an exciter converter that provides a non-fundamental only signal to a field winding of an exciter of the synchronous generator. The non-fundamental signal provides a first rotating field for the field winding of the exciter. Exciter armature windings induce an AC signal from the rotating field where at least one rectifier rectifies the induced AC signal. A field winding of a main machine provides a flux from the rectified signal of the at least one rectifier. Armature windings of the main machine receive an AC signal via a main machine converter.

Abstract: Method for defining quadrature-axis magnetizing inductance of a synchronous machine, the synchronous machine being supplied by an inverter. The method comprises steps, wherein the synchronous machine is started without load or with reduced load; the rotor current of the synchronous machine is kept substantially at zero, the synchronous machine is accelerated to initial angular velocity of measurement, the load angle (ds) of the synchronous machine is guided substantially to 90 degrees, the stator voltage (us), the stator current (is) and the electrical angular velocity (?) of the synchronous machine is defined and the quadrature-axis magnetizing inductance of the synchronous machine (lmq) is defined on the basis of the stator voltage (us), the stator current (is) and the electrical angular velocity (?) of the machine.

Abstract: In a motor control apparatus of the present invention, a control section which receives an input voltage to an inverter circuit, a motor current flowing to a brushless motor and a motor current command value indicating the value of a current required to flow to the inverter circuit, and controls the inverter circuit by maintaining a phase of the voltage applied to the brushless motor when the value of the input voltage to the inverter circuit is smaller than the value of a voltage required to be applied to the brushless motor.

Abstract: In a conventional rotation state detecting apparatus of a synchronous machine, since short-circuiting must be carried out twice or more when a rotation speed is detected, there have been problems in that it takes a time to detect a rotation state, and it takes a time to start up. A rotation state detecting apparatus for a synchronous machine according to the present invention has been made to solve the above problem, and includes a calculation unit for outputting a voltage vector command and a trigger signal and for outputting a rotation state of a synchronous machine having at least three windings in an idle state, a circuit unit for applying voltages to the respective phases of the synchronous machine on the basis of the voltage vector command, and a detection unit for detecting a current of the synchronous machine on the basis of the trigger signal and outputting a value of the detected current to the calculation unit.

Abstract: A method and system for modifying an estimated rotor angle for improved efficiency in a PMSM drive system. A module monitors a run command, a torque command, and an estimated speed; and in response thereto, generates an output correction angle for modifying the estimated rotor angle. The output correction angle may be added to the estimated rotor angle. The output correction angle may be generated only for predetermined conditions of said run command, torque command, and speed. In particular, the output correction angle may be generated (1) when the run command is asserted, (2) when the torque command is above a predetermined level, and (3) when variations in the speed are within predetermined limits.

Abstract: A power converter device for a switched reluctance motor, comprises a semiconductor circuit arrangement in the form of an asymmetric inverter, to supply one of the motor windings on the reluctance motor with current or to commutate the current from the winding. The achievement of the maximum possible current amplitude may be accelerated and the commutating of the current from the motor winding may be accelerated, whereby, in addition to the main voltage source, an additional voltage source in the form of a circuit extension is provided, which, by means of providing an additional voltage of corresponding polarity, accelerates the current feed to the relevant motor winding, or accelerates the removal of the current (commutating) from the motor winding.

Abstract: This invention relates to a variable speed drive with synchronous AC motor. In the disclosed embodiment, a variable speed drive operates in three modes: a first predetermined mode, in which a function (e.g., trapezoidal current waveform) controls operation at low motor speeds; a transitional mode, in which a transition function is applied to anticipate transitions of the first function, thus causing a smoothing of transitions at higher speeds; and a second predetermined (e.g., sinusoidal or smoothly-varying current) waveform at high speeds. This allows for the reduction in required rotor position sensor resolution as compared to conventional synchronous variable speed drives, resulting in cost savings in the sensor device and associated wiring. Additionally, it is quieter and more efficient operation at high speed as compared to conventional trapezoidal-current/DC-brushless motor drives.

Abstract: A DC motor drive circuit includes a position detector for producing an output signal that corresponds to a rotational position of the rotor, a current controller for controlling current supply to the winding in accordance with the output signal of the position detector, and a phase advancing portion for the current between the position detecting portion and the current controller, so that the timing for supplying current to the winding is advanced and efficiency of converting the current supplied to the winding into a motor torque is improved.

Abstract: A motor control device includes an electric voltage command value calculation means for inputting an electric current command value every control cycle, calculating an electric current deviation integrated value by integrating an electric current deviation between the electric current command value and an actual electric current value at a coil of a motor, and calculating an electric voltage command value in accordance with the electric current deviation integrated value. The electric voltage command value calculation means controls the electric current deviation integrated value not to exceed a saturation electric voltage value, a value according to the maximum value of the electric voltage outputted from the inverter circuit to the motor.

Abstract: In a synchronous motor control device that corrects a deviation in rotational position which is related to a rotational position detector for a synchronous motor on which vector-control is performed, the synchronous motor control device includes: a current instruction generator that disables a torque instruction to set d-axis and q-axis current instructions as zero when a phase correction instruction is inputted; a current controller that outputs d-axis and q-axis voltage instructions based on the d-axis and q-axis current instructions; a phase correction quantity detector for determining the amount of offset in which the d-axis voltage instruction becomes zero when the phase correction instruction is inputted and the d-axis voltage instruction is not zero; an adder for adding a rotor positional angle and the amount of offset; and a voltage converter for determining three-phase voltage instructions based on the additional value, the d-axis and q-axis voltage instructions.

Abstract: A synchronous motor controller and method of controlling a synchronous motor without using rotor position sensors are provided. In a floating synchronous reference frame controller, phase currents are measured and a current Park vector is determined. The error between an initially arbitrary floating reference frame is reduced with a control loop. Decoupling terms based on the estimated speed of the rotor and the stator winding inductance are used to generate decoupled voltage terms in the v- and u-axis of the floating synchronous reference frame. The decoupled voltage command is converted back to a stator reference frame and applied to the synchronous motor via a power electronic converter. As a result u-axis current is minimized during transients, and a robust and accurate estimation of the current vector to be used in coordinate transformation for controlling the machine are achieved and the need for overrating of motor and inverter components is avoided.