Abstract: A system and method for user configuration of an autotuning algorithm for a PID controller. User input is received via a Graphical User Interface (GUI) indicating a desired characteristic of a PID controller, such as stiffness or response time. The system is excited via a proportional controller to characterize the intrinsic behavior of the system, i.e., to calculate a system transfer function. An autotuning algorithm is configured in accordance with the user input. The configured autotuning algorithm is applied to the transfer function to generate gain values for the PID controller resulting in the PID controller characteristic specified by the user. The PID controller gains are loaded into the PID controller hardware or software, thereby configuring the PID controller to operate according to the desired characteristic specified by the user. The user may trigger and view a step response of the system to review the results of the tuning process.

Abstract: An integrated control and diagnostics system for a controlled system (e.g., a motor) includes a diagnostics module and a controller coupled to the motor. To optimize operation, the diagnostics information signal is used to modify the control provided by the controller as required. Moreover, the output of the control module is coupled to the diagnostics module so that the health assessment made by the diagnostics module can be based at least in part on the output of the controller. The invention uses a model-based diagnostics approach that allows integration of control algorithms with diagnostics algorithms to intelligently trade off optimizing performance to avert or accommodate failures, and to meet performance requirements in a wide range of applications.

Abstract: A cabin pressure control system (CPCS) software control logic modification may boost the voltage applied to a motor by applying a duty cycle offset to compensate for asymmetric motor loading. The motor may be part of an open-loop system for operating a butterfly valve that may regulate outflow from the aircraft cabin. In CPCS applications, the loading on the butterfly valve is unidirectional due to a mechanical spring and pneumatic loading, thus, causing asymmetric loading to the motor. By boosting the motor voltage when the motor is required to act against the asymmetric load, CPCS performance and robustness may be improved.

Abstract: An actuator includes a motor operated by a controller through a pulse width modulation drive signal applied to a drive circuit that drives the motor. The actuator has an output shaft connected to a coupling structure for manipulating a device such as a variable geometry turbine (VGT) or an exhaust gas recirculation (EGR) valve. The device has a range of motion limited by first and second mechanical stops located at opposing low and high ends of the range. The controller learns the location of the mechanical stops during calibration. An external control unit transmits a desired position to the actuator. A protocol allows the external control unit to implicitly request a positioning mode by virtue of what value range the desired position falls into. The controller is configured to limit the drive signal to a non-harmful level when one of the positioning modes calls for pushing the device against one of the stops.

Abstract: In a stabilizer control apparatus for transmitting a power through a speed reducing mechanism, a rolling motion of a vehicle body is restrained smoothly and rapidly, without being affected by transmitting efficiency of the speed reducing mechanism. As for a stabilizer (SBf) including a pair of stabilizer bars (SBfr, SBfl) disposed between a right wheel and a left wheel, and a stabilizer actuator (FT) driven by an electric motor disposed between them, the electric motor M is controlled in response to a turning state of a vehicle, to control a torsional rigidity of the stabilizer. Furthermore, the apparatus comprises relative position detection means for detecting the relative position of the pair of stabilizer bars (for example, obtained from a relationship between a rotational angle of the electric motor and a reducing speed ratio), and it is so constituted that the electric motor is controlled in response to the detected result.

Abstract: A motor control apparatus 1 that controls a rotation speed of a motor driven according to a speed command includes an abnormal-rotation detector 21 which determines that the motor is in an abnormal-rotation state, such as a runaway, when a speed deviation Ver obtained by subtracting a detection speed TSA of a motor rotation from a speed command VCMD is equal to or larger than a threshold value, when a sign of a product of acceleration ?TSA obtained by subtracting a last detection speed from a detection speed this time that is detected in a predetermined cycle and a torque command Tc obtained by proportionally integrating the speed deviation is negative, and when an integration value VerSUM of the speed deviation Ver exceeds a predetermined value ALMlevel. With this arrangement, an abnormal rotation of the motor can be instantly detected even during acceleration or deceleration of the motor, thereby increasing the performance of protecting the motor.

Abstract: The invention applies to a vibrator comprising two pairs (A, B) of unbalanced rotors (10 to 13) driven in synchronous rotation by a first motor, and a second motor arranged to drive a phase shifter mechanism so as to adjust a phase difference between the first pair of rotors and the second pair of rotors; the system comprises: a sensor (C1) for sensing rotation of a rotor of the first pair of rotors; a sensor (C2) for sensing rotation of a rotor of the second pair of rotors, or for sensing the position of the phase shifter mechanism; means for controlling the rotation of the first motor as a function of the phase and the frequency of a force setpoint signal and as a function of the signals delivered by the sensors; and means for controlling the rotation of the second motor as a function of the phase, the frequency, and the amplitude of the force setpoint signal and as a function of the signals delivered by the sensors.

Abstract: A method of controlling, by an adaptive control method, an electric motor as a drive source of an operating apparatus that operates, based on a driving force produced by the electric motor, under an arbitrary one of a plurality of operating conditions, and exhibits different dynamic characteristics corresponding to the plurality of operating conditions.

Abstract: A system, method, and article for protecting a power source for a machine from sudden changes in load. In one embodiment, energy is wasted in a winding of a motor in response to a decrease in a load presented to the power source.

Abstract: A medical robotic system has a joint coupled to medical device or a slave manipulator or robotic arm adapted to hold and/or move the medical device for performing a medical procedure, and a control system for controlling movement of the joint according to user manipulation of a master manipulator. The control system includes at least one joint controller having a sliding mode control for reducing stick-slip behavior on its controlled joint during fine motions of the joint. The sliding mode control computes a distance to a sliding surface, computes a reaching law gain, and processes the distance and reaching law gain to generate a sliding mode control action that is in absolute value less that a maximum desired feedback control action. The sliding mode control action is then further processed to generate a feedback torque command for the joint motor.

Abstract: Methods and apparatus for controlling a polyphase motor in implantable medical device applications are provided. In one embodiment, the polyphase motor is a brushless DC motor. The back emf of a selected phase of the motor is sampled while a drive voltage or the selected phase is substantially zero. Various embodiments utilize sinusoidal or trapezoidal drive voltages. The sampled back emf provides an error signal indicative of the positional error of the rotor. In one embodiment, the sampled back emf is normalized with respect to a commanded angular velocity of the rotor to provide an error signal proportional only to the positional error of the motor rotor. The error signal is provided as feedback to control a frequency of the drive voltage. A speed control generates a speed control signal corresponding to a difference between a commanded angular velocity and an angular velocity inferred from the frequency of the drive voltage.

Abstract: A scanner system includes a servo control unit. A rotation angle of a rotating shaft supporting a mirror is detected, and an error of the detected value with respect to a commanded value is integrated by an integral compensator so that the detected value is able to track the commanded value. A tracking error proportional compensator is disposed in parallel with the integral compensator so as to add a correction value proportional to the error to the integrated value of the error. A plurality of gains are prepared for each of the integral compensator, the tracking error proportional compensator, a detected value proportional compensator and a detected value differential compensator of the servo control unit. Each gain is changed in accordance with a travel angle of the commanded value. Thus, the mirror can be positioned quickly so that the machining speed can be improved.

Abstract: Methods for controlling at least two actuators are provided. An internal control system sends an input received from the main control system to a first actuator and diverts a portion of the input to a second actuator when an input constraint of the first actuator is reached. The actuators may be throttle valves for heating a hydraulic line. The internal control system includes a cutoff rerouter for implementing the sending and the diverting of the input and an adaptive cutoff controller, e.g., an integral controller, for determining the input constraint of the first actuator.

Abstract: A fan controller may be integrated in silicon and may use an embedded microcontroller to implement a digital fan control algorithm. The microcontroller may continually monitor temperature and sample the speed of the controlled fan. The speed of the fan may be compared to RPM values fitted on a desired curve that is representative of the Temperature-versus-RPM function for the controlled fan. The fan control algorithm may be based on a ramp-rate closed-loop controller (RRCC), which may be operated to drive the fan to the desired speed at different rates, depending on the difference between the desired RPM and the actual RPM of the fan. The fan may also provide a Fan ID feedback signal to the microcontroller, which may use the Fan ID feedback signal upon system start-up to initialize the RRCC range settings and select the appropriate Temperature-versus-RPM function curve based on pre-determined values for the given fan.

Abstract: Regulation of the active and reactive power of an induction machine in a coordinate system fixed on the winding, wherein a first regulator output variable is generated using a first regulator as a function of a setpoint variable deviation of the active power and a second regulator output variable is generated using a second regulator as a function of a setpoint variable deviation of the reactive power, feedback variables are added to each of the first and second regulator output variables, which are functions of at least one chronologically changing system variable of the induction machine, and a voltage or a current of the induction machine is determined as a manipulated variable without further regulation at least from the first and second regulator output variables added to the feedback variables. The feedback variables may linearize the regulation path and then allow restriction to only two simple regulators, e.g., two PI regulators. The regulation may be used in double-fed asynchronous machines.

Abstract: An active front steering system includes a motor controller configured to compute a position error from a commanded position value and an actual position value, and then enter one of two modes—a commutation enable mode and a commutation freeze mode—depending upon the value of this position error. The commutation freeze mode applies when the absolute value of the position error is less than a predetermined threshold, and involves sending a set of signals to the motor's phase inputs such that commutation of the motor is prevented and a substantially constant motor hold torque is produced. The commutation enable mode applies when the absolute value of the position error is greater than or equal to the predetermined threshold, and corresponds to normal commutating operating mode.

Abstract: The present invention is a motor control device comprising a control system, the control system being capable of controlling the motor by PWM and having integration means being capable of outputting an integrated value obtained by integrating a deviation between a rotation speed and a target rotation speed of a motor, the motor control device being capable of starting control with the control system for causing the motor to rotate at the target rotation speed after rotation of the motor has been started. In this motor control device, an output value of the integration means at a time when control with the control system is to be started is set to have a value that corresponds to a counter electromotive force generated in the motor by its rotation.

Abstract: Methods, control systems, and information handling systems for controlling at least two actuators are provided. An internal control system sends an input received from the main control system to a first actuator and diverts a portion of the input to a second actuator when an input constraint of the first actuator is reached. The actuators may be throttle valves for heating a hydraulic line. The internal control system includes a cutoff rerouter for implementing the sending and the diverting of the input and an adaptive cutoff controller, e.g., an integral controller, for determining the input constraint of the first actuator. The information handling systems include a determination logic for determining if an input received from the main control system is greater than an input constraint of the first actuator and a diverting logic for diverting a portion of the input to a second actuator when the input is greater.

Abstract: This application describes the software invented to control a dual electric motor system. The dual electric motor system is a Chorus Motor system applied to electric drive for aircraft taxi. The software uses closed-loop control together with several other control laws to operate the motors. Knowledge of the current operating state of the motors, together with knowledge of the commands given to taxi forward, taxi in reverse, or brake in reverse, is used to configure the motors to optimal operating parameters. The software architecture is described along with the pilot interface and many details of software implementation.

Abstract: An active front steering system includes a motor controller configured to compute a position error from a commanded position value and an actual position value, and then enter one of two modes—a commutation enable mode and a commutation freeze mode—depending upon the value of this position error. The commutation freeze mode applies when the absolute value of the position error is less than a predetermined threshold, and involves sending a set of signals to the motor's phase inputs such that commutation of the motor is prevented and a substantially constant motor hold torque is produced. The commutation enable mode applies when the absolute value of the position error is greater than or equal to the predetermined threshold, and corresponds to normal commutating operating mode.

Abstract: A method and apparatus control a power converter (20) of a motor drive system. The power converter (20) is controlled during a first operating mode by applying a current control scheme, which sets power converter commands to control active and reactive current components flowing from the power converter (20) to the motor (30) to achieve desired motor speed; and a fault protection scheme is executed during a second operating mode. The fault protection scheme generates power converter commands to reduce the active current component flowing from the power converter (20) to the motor (30) is substantially zero. The first operating mode will be resumed upon receiving the restart command if the motor speed is above a pre-set shutdown threshold.

Abstract: A method for differentiating if a feedback signal is a result of an unintentional collision in a servo system includes injecting a feed forward term in the servo system.

Abstract: Systems and methods are presented that cancel the dynamics of a motor and a joint controller in the presence of communication time delays, measurement noise, and controller parameter uncertainties inherent in a robot system. A cancellation system includes feedback of the measured output Ê of a controller block C. A first summing node (?1) subtracts Ê from the desired voltage Ed to determine a voltage error, which is fed into a G(s) block. A second summing node (?2) adds the output of the G(s) block to the desired voltage Ed to generate the signal ?, which is fed into a non-robust controller inversion block C?1. The block C?1 outputs a value ?, which is fed into the block C. The block C outputs the actual voltage E, which is input into a motor block M. Under perfect conditions, the voltage error is zero, in which case the input to block G(s) is zero.

Abstract: A method of analyzing a limited rotation motor system is disclosed. The method includes the step of providing a motor control frequency domain signal that is representative of a frequency domain representation of the motor control signal responsive to a first digital signal that is representative of a motor control signal. The method also includes the step of providing a position detection frequency domain signal that is representative of a frequency domain representation of the position detection signal responsive to a second digital signal that is representative of a position detection signal.

Abstract: An object of this invention is to provide a gain adjusting method in a servo control device to suppress changes according to a place where a machine is located. This invention provides a gain adjusting method for a servo control device providing speed control of inputting a difference between speed feedback supplied from a servo motor and a command value to output a torque command, characterized in that after a speed loop gain is increased to detect vibration at each of points moved over a movable range of a machine, the speed loop gain is decreased to detect the gain when the vibration becomes still as a maximum value, thereby providing a set gain value corresponding to a machine.

Abstract: A movement controlling unit performs movement control of a head toward a target track on a magnetic disk medium driving a head actuator, and a position controlling unit performs position control of the head actuator in accordance with proportional integral calculations such that a deviation of a head position relative to a track center is eliminated when the moving head arrives at the target track. A gain retaining unit retains an integral gain of the proportional integral calculations in an increased state during a predetermined retention time from the start of the position control, and a gain switching unit switches the increased integral gain smoothly to the original integral gain when the retention time has elapsed.

Abstract: In a laser printer, methods and apparatus include commutating a brushless dc motor having three windings. A controller receives discrete motor position signals, such as from hall-effect or FG sensors, and extrapolates motor position between the signals. It commutates the motor based on the extrapolated motor position and updates motor position whenever an actual discrete signal is received. Drive signals from the controller to the motor are such that a current flowing in any of the three windings follows a generally sinusoidal waveform. High and low switches are provided per each winding of the three windings and are cumulatively switched according to an extrapolated motor position based multiplier applied to a pulse width modulation duty cycle. In this regard, lookup tables, counters, registers and the like are provided. An engine card of the printer includes an ASIC with a power driver for use with generally off-the-shelf brushless dc motors.

Abstract: A different adaptive control method is used to control a motor during each of two or more phases of motor operation. Thus, in a first phase of motor operation the motor is controlled using a first adaptive control method, in a second phase of motor operation the motor is controlled using a second adaptive control method, and so forth. The motor can be controlled in this manner in any number of phases, in which the motor is used for any of a number of corresponding purposes. The method used in each phase can be optimized to suit that type of operation without compromising operation during other phases.

Abstract: Feedback control of a target system is provided which utilizes the imposition of a periodic modulating signal onto a command signal of a controller. The command signal with the period modulating signal imposed thereon is input to the target system to be controlled. A response of the target system to a manifestation of the periodic modulating signal in the command signal is detected, and a feedback signal is produced from the detected response. The periodic modulating signal and the feedback signal are processed together to produce an error signal, and the command signal is modified in accordance with the error signal to drive the current state of the target system toward a desired state, wherein the periodic modulating signal facilitates control of the target system.

Abstract: The present invention relates to a method for limiting the current output by a speed controller (V) for three-phase asynchronous electric motor (M), said controller (V) operating according to a control law (LC) of pure U/F type. Said method is characterized in that it consists in calculating with the aid of a limitation function a correction value for the frequency of the stator (Wstat) then in applying thereto, so as to obtain, in the voltage control law (LC) of U/F type, a corrected frequency of the stator (Wstatc). According to the voltage control law of U/F type, the method thereafter consists on the basis of this corrected frequency of the stator (Wstatc) in obtaining the control voltage (Vqref) applied to the motor. The invention also relates to a system for limiting the current able to implement said method.

Abstract: A control device for a vehicular opening/closing body is provided with a duty ratio calculator (78), which calculates a duty ratio when power supplied to a door drive motor (48) allowing an opening/closing body to open/close is subjected to duty control based on a result of adding first second multiplication values, the first multiplication value being obtained by multiplying a speed difference between a target opening/closing body speed and an actual opening/closing body speed by a negative proportional gain, and the second multiplication value being obtained by multiplying an integral value of the speed difference by an integral gain.

Abstract: An adjustment system is disclosed for adjusting a proportional, integral, derivative controller in a limited rotation motor system. The adjustment system includes a first transform unit, a second transform unit, a model identification unit, and a PID adjustment unit. The first transform unit is for receiving a first digital signal that is representative of a motor control signal, and is for providing a first frequency domain sequence that is representative of a frequency domain representation of the motor control signal. The second transform unit is for receiving a second digital signal that is representative of a position detection signal, and is for providing a second frequency domain sequence that is representative of a frequency domain representation of the position detection signal. The model identification unit is for identifying a representation of a ratio of the first and second frequency domain sequences.

Abstract: A method and system are disclosed for controlling a process by establishing a control factor for a proportional-integral-derivative (PID) controller used to control a parameter of a process relative to a setpoint. A feedback signal regarding the parameter of the process is received via a sensor of the process and a first feedback loop. Automatic adjusting of the control factor of the PID controller is based on the feedback signal.

Abstract: A diagnostic system is disclosed for analyzing a limited rotation motor system. The diagnostic system includes a first transform unit, a second transform unit, a closed loop frequency response unit, and a diagnostic system. The first transform unit is for receiving a first digital signal that is representative of a motor control signal, and is for providing a motor control frequency domain signal that is representative of a frequency domain representation of the motor control signal. The second transform unit is for receiving a second digital signal that is representative of a position detection signal, and is for providing a position detection frequency domain signal that is representative of a frequency domain representation of the position detection signal. The closed loop frequency response unit is for identifying a representation of the frequency response of the limited rotation motor responsive to the position detection frequency domain signal and the motor control frequency domain signals.

Abstract: A motor torque control apparatus for an automotive vehicle includes a transmission which has either one of a fixed speed ratio and a variable speed ratio; at least one motor/generator coupled with the transmission as a propelling power source of the vehicle, a power of the power source being transmitted to a road wheel for propulsion of the vehicle through the transmission; and a controller configured to be electrically connected to the motor/generator for motor torque control. Moreover, this controller includes a disturbance observer that estimates a driving force, and a motor torque control section that controls the driving force estimated by the disturbance observer, to bring the estimated driving force closer to a target driving force by way of servo control.

Abstract: A system and method for controlling a fan is disclosed. In one embodiment, a fan controller is integrated in silicon and uses an embedded microcontroller to implement a digital fan control algorithm. The microcontroller may continually monitor temperature and sample the speed of the controlled fan. The speed of the fan may be compared to RPM values fitted on a desired curve that is representative of the Temperature-versus-RPM function for the given controlled fan. The fan control algorithm may be based on a PID compensator or a Ramp Rate Closed-loop controller (RRCC), which may be operated to drive the fan to the desired speed. The fan may also provide a Fan ID feedback signal to the microcontroller, which may use the Fan ID feedback signal upon system start-up to initialize the PID compensator gain settings or the RRCC parameter settings, and select the appropriate Temperature-versus-RPM function curve based on pre-determined values for the given fan.

Abstract: A correction value calculating method includes: preparing a printer including a motor, a PID control system for controlling the motor, and a memory for storing a correction value, the printer being configured to calculate a value of a current flowing through the motor based on the correction value and an output value of an integral element of the PID control system; obtaining in advance a relationship, for when a property of a motor fluctuates, between a correction value and a sum of an output value of the integral element when a motor is driven at a first velocity and an output value of the integral element when the motor is driven at a second velocity; driving the motor of the printer at the first velocity and measuring an output value of the integral element at that velocity; driving the motor of the printer at the second velocity and measuring an output value of the integral element at that velocity; and determining the correction value to be stored in the memory based on the relationship and a sum of the

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: Methods and devices for brushless DC motor operation. An example method may include using previously sensed Hall effect sensor transitions to predict a future Hall effect transition, and dividing a time between a most recent Hall effect sensor transition and the predicted Hall effect sensor transition into time increments. The time increments may be used to effect phase advance by selecting a number of time increments to create a time offset for phase advance purposes. The time increments may also be used as a virtual encoder. Devices incorporating controllers and control circuitry for performing like methods are also discussed.

Abstract: Feedback control of a target system is provided which utilizes the imposition of a periodic modulating signal onto a command signal of a controller. The command signal with the period modulating signal imposed thereon is input to the target system to be controlled. A response of the target system to a manifestation of the periodic modulating signal in the command signal is detected, and a feedback signal is produced from the detected response. The periodic modulating signal and the feedback signal are processed together to produce an error signal, and the command signal is modified in accordance with the error signal to drive the current state of the target system toward a desired state, wherein the periodic modulating signal facilitates control of the target system.

Abstract: A method of regulating a target system generates a plurality of digital signals which define a reference pulse train with a frequency dependent upon a reference signal. A target system to be regulated (such as a transport speed of a paper transport assembly in a printer) has an output in the form of a plurality of digital signals defining a feedback pulse train having a frequency. The frequency of the reference pulse train is compared with the frequency of the feedback pulse train. A control signal is generated dependent upon the frequency comparison, and is provided as an input to the target system.

Abstract: An object of the present invention is to provide an electric power steering apparatus which can continue control even if some of current detectors that detect phase currents of a three-phase motor break down. Phase currents of the failure current detectors are calculated by using detected signals from the normal current detectors, and the electric power steering apparatus can be continued to be controlled by using the current values.

Abstract: A motor control device that can reduce electrical noise is provided. A motor control device includes an inverter, a current controller, a high frequency wave superpositioner, and a high frequency wave setter. An inverter applies a current to the motor. A current controller outputs a voltage to the inverter according to a current applied to the motor from the inverter. A high frequency wave superpositioner applies a high frequency wave to the voltage from the current controller as a superpositioned wave to infer a position of a rotor in the motor. A high frequency wave setter varies at least one characteristic of the superpositioned wave applied by the high frequency wave superpositioner.

Abstract: A motor control device comprises: a current limiter 115 for limiting a current-instruction signal Ir for a motor 18 and for turning a limiting signal L from off to on when the current-instruction signal Ir reaches a predetermined value; a model-position-generating part 220 having a model of an equivalent position-control system that includes characteristics of the motor control device 100 and a control target object, and calculating rotational position of the motor 18 as a model-position signal ?m by inputting to the model a position-instruction signal ?r; a correctional acceleration-generating part 240 for generating a correctional acceleration signal ?se based on a correctional position deviation ?se when the limiting signal L turns on; and a position-instruction-generating part 260 for generating the position-instruction signal ?r based on an acceleration deviation ?r that is equal to the difference between the original-acceleration-instruction signal Va and the correctional acceleration signal ?se.

Abstract: An electrically operated drive controller includes first and second electric current command value calculation processors, for calculating first and second electric current command values from a target value of torque of an electrically operated machine; a voltage command value calculation processor, for calculating a voltage command value from the first and second electric current command values; and first and second adjusting value calculation processor, for calculating first and second adjusting values. The first electric current command value calculation processor includes first electric current command value adjustment processors, for adjusting the first electric current command value by the first adjusting value, and an electric current limit processor, for limiting the adjusted first electric current command value.

Abstract: A method for controlling in an open-loop voltage mode a DC motor driven through a power amplifier includes generating a control voltage for the DC motor to be input to the power amplifier based upon a difference between an external command and a correction signal, and amplifying the control voltage for generating a replica of an output of the power amplifier. A model of the DC motor is defined based upon electrical parameters of the DC motor. The method further includes estimating current flowing in the DC motor based upon the replica of the output of the power amplifier and the model of the DC motor, and generating the correction signal proportional to the estimated current.

Abstract: An electrically operated drive controller includes first and second electric current command value calculation means which calculate first and second electric current command values based on a target value of torque of an electrically operated machine. The controller also includes a voltage command value calculation processing means which calculates a voltage command value based on the first and second electric current command values and an adjusting value calculation processing means for calculating an adjusting value of the first electric current command value and for performing weak field control based on the voltage command value. The first electric current command value calculation processor adjusts the first electric current command value based on the adjusting value. The second electric current command value calculation processor adjusts the second electric current command value based on the adjusted first electric current command value.

Abstract: A driver for an electric actuator comprises a direction-switching means which switches a direction of rotation of a rotary driving source based on a direction instruction input signal, a current amplifier/limiter which converts a voltage outputted from the direction-switching means into a corresponding current and which limits the current with reference to a preset reference current IMAX or a threshold value, a current sensor which detects the current supplied to the rotary driving source, and a current loop by which a detection signal from the current sensor is fed back to an upstream side of the current amplifier/limiter.

Abstract: A method for decoupling a harmonic signal from an input signal wherein the harmonic signal is harmonic relative to a signal other than the input signal. An angular position of the other signal is multiplied by a value representing the harmonic to obtain an angular position multiple. A harmonic decoupling block uses the angular position multiple to obtain correction signals representing the harmonic signal, and subtracts the correction signals from the input current to decouple the harmonic signal from the input signal. This method is useful for decoupling unwanted harmonics from currents into which high-frequency signals have been injected for control of electric motors.

Abstract: A method for differentiating if a feedback signal is a result of an unintentional collisions in a servo system includes injecting a feed forward term in the servo system.