Abstract: A control constant adjusting apparatus in a control apparatus of a robot or a machine tool, etc. is disclosed. This control constant adjusting apparatus includes a speed control part (12), an estimation part (13), an identification part (14) and an adjustment part (15). The identification part (14) makes identification of inertia J obtained from a ratio between a value |SFTr| in which an absolute value |FTr| of a value FTr obtained by passing a torque command Tref of the speed control part (12) through a predetermined high-pass filter is integrated with respect to time at a predetermined interval [a, b] and a value |SFTr?| in which an absolute value |Ftr?| of a value FTr? obtained by passing a model torque command Tref? of the estimation part (13) through a predetermined high-pass filter is integrated with respect to time at the same interval only when a speed Vfb? of a model in the estimation part (13) matches with a motor speed Vfb in the speed control part (12) at a value other than zero.

Abstract: This invention relates to a motor controller for driving an object to be controlled by torque from a motor responding to a computed torque command, the object being provided with the motor and a mechanical load. The motor controller includes: a feedback computation unit into which is inputted a positional command signal or a speed command signal, and a motor rotational signal which is a detected value of the motor's rotational angle or speed, the feedback computation unit being for computing the torque command by a computation in which the transfer function for a feedback loop from the motor rotational signal to the torque command includes a pole or a zero point; a response parameter input unit for inputting a response parameter; and a ratio parameter input unit for inputting a ratio parameter. A loop gain which is the gain of the feedback loop is determined based on the response parameter.

Abstract: Method and apparatus for controlling a moving speed of a moving body, wherein at least one transient target speed value in addition to a final target speed value is used to control the moving speed in an accelerating period between a moment of initiation of a movement of the moving body and a moment at which the moving speed should coincide with the final target speed value. The transient target speed is updated at a predetermined timing, or changed to the final target speed value, or from one transient value to another transient value before it is changed to the final target speed value, so that the moving speed is smoothly increased to the final target speed value, without an overshoot beyond the final target speed value.

Abstract: A motor control apparatus of the present invention comprises a velocity detector for detecting a rotation velocity of a mover of a motor, a position detector for detecting a position of the mover, a differentiator for performing time differentiation with respect to the position detected by the position detector to obtain a velocity calculation value, a feedback signal generating circuit for generating a feedback signal including the velocity detection value obtained by the velocity detector as a high frequency component and the velocity calculation value obtained by the differentiator as a low frequency component, and a linear amplifier and an integrating amplifier for performing PI control, the linear amplifier and the integrating amplifier performing linear amplification and integrating amplification of a difference between the velocity instruction and the feedback signal, respectively.

Abstract: A carriage driving apparatus that drives a carriage of a printer or the like by a motor and a motor control method for controlling the motor can substantially eliminate variation in control accuracy among individual apparatuses. Each set of various parameters are determined with respect to each ultimate target speed of the carriage and each moving direction, and contained in a table. Three kinds of tables, i.e. a table for heavy load, a table for light load and a table for standard load in accordance with the difference in load applied to individual drive systems of the carriage, as well as one kind of table for low temperature are prepared and stored on a ROM. It is determined which of the three kinds of tables should be selected at normal temperature by actually driving the carriage in the final step of the manufacturing process.

Abstract: The present invention provides an electric brake system which detects the occurrence of overshooting, and corrects a feedback gain in the PID feedback control at overshooting. For example, it increases a differential gain Kd. Accordingly, a damping force increases from the time when the overshooting is determined, and after the overshooting, the output of an electric brake moderately decays to get closer to the target value with the passage of time.

Abstract: A system for allowing a wide selection of components to affect a desired result in the positioning business. Up to nine axes of coordinated motion are offered each of which may use a servomotor, a single or double rod air cylinder. The control for the system is a series of digital commands that cause the cylinder to accelerate, decelerate, maintain a given velocity, stop or pause and repeat a series of commands. It uses a low power servo system which, when activated, opens an air valve to an air cylinder which then moves until the valve actuator is turned off by the cylinder thus causing the air cylinder to follow the lower power servo system.

Abstract: A device and method for apportioning a movement of a machine element driven by at least two drives for movement along a drive axis of a machine tool or production machine are described. A low-pass filter filters predetermined desired drive axis values to generate filtered desired drive axis values, with a first controller receiving the filtered desired drive axis values as control input value for controlling a first of the at least two drives. A delay unit with a constant group delay time temporally delays the desired drive axis values and generates delayed desired drive axis values, whereafter a subtracter determines a difference between the filtered desired drive axis values and the delayed desired drive axis values. A second controller receives the determined difference and provides, based on the determined difference, a second control input value for controlling a second of the at least two drives.

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: The PDT2 filtering element (PDT2) and a Cauer filter (C2) are employed for use in control tasks of automation engineering, in particular for a filter connected downstream of a rotational speed controller. For tasks in control engineering, these have the advantage of a higher level of robustness, since a large frequency range is filtered, and a substantially smaller phase drop than conventional lowpass filters (PDT2). Consequently, by comparison with the known prior art a loss in dynamics is substantially minimized with these phase-saving lowpass filters, and an optimum is achieved in robustness and dynamics.

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.

Abstract: A method for tuning a PID controller includes the steps of inducing equivalent relationships between PID gains of the PID controller and parameters of time delay control (TDC), selecting a natural frequency vector and a damping ratio vector so as to acquire a desired error dynamics of the closed PID control loop system, selecting a sampling time of the closed PID control loop system, determining the parameters of TDC on the basis of the natural frequency vector, the damping ratio vector and a closed loop stability condition for TDC, and selecting PID gains of the PID controller on the basis of the equivalent relationships.

Abstract: To eliminate unwanted vibrations caused by synchronous disturbances, such as synchronous disturbances caused by an imbalance, for example, the invention proposes a compensation device for closed loop compensation of a synchronous disturbance in a rotating machine comprising a rotor (64) magnetically suspended by at least one radial magnetic bearing (63) comprising electromagnets (631, 632) driven by amplifiers (61, 62), a radial detector device (633, 634) for sensing the axial position of the rotor, and a closed loop servocontrol circuit connected to said detector device and to said electromagnets and comprising a control circuit (5) for controlling the energization of the electromagnets that supplies a control signal (u) to said amplifiers in response to signals supplied by the detector device to maintain the rotor in a predetermined axial position. The compensation device comprises means (100; 200; 300) for generating a signal for compensating the synchronous disturbance.

Abstract: A control system for an electric motor having a stator and rotor including an inverter for providing power to the electric motor, a controller for controlling the inverter, a low speed control block to estimate the rotor angular position using stator current components operating in the controller, a high speed control block to estimate the rotor angular position using stator current components and stator flux position operating in the controller, a transition switch in the controller to vary operation between the low speed control block and the high speed control block, and where the inverter is controlled by six step operation.

Abstract: An adjustable iri-diaphragm controller includes a brushless direct current (DC) motor, an iris defining an aperture that corresponds to an angular position of the DC motor, and a control module including a differential circuit, an integrator, and a current-limiting circuit. The differential circuit provides an output voltage corresponding to a difference between a first voltage corresponding to the angular position of the DC motor, and a second voltage corresponding to a reference aperture. The integrator provides an output signal corresponding to the output voltage. The current-limiting circuit limits supply of electric current to the DC motor in accordance with the control output signal, and inhibits the supply of the electric current to stop further rotation of the DC motor when the DC motor is rotated to an angular position corresponding to the reference aperture.

Abstract: A position control system uses a speed command supplied to a driving source. The speed command has a change pattern which has an acceleration section (1) for eliminating a dead zone of a power transmission mechanism, a constant-speed section (or an acceleration section with a slower acceleration than in the section (1)), an acceleration section (3) up to the maximum speed, a constant-speed section (4), a deceleration section (5), a constant-speed section (6) for eliminating the dead zone (or a deceleration section with a slower deceleration than in the section (5)), and a deceleration (7) for stopping at a target section. Even when a driven member has large inertia, the position thereof is accurately controlled to the target position in a semi-closed position control system.

Abstract: Damping of mechanical oscillation in a shaft that is provided by feedback wherein the output signals of multiple feedback devices are negatively coupled and added to a desired speed signal of a motor speed controller of the driving motor is disclosed. At least one sensor and/or measuring system can be provided for measuring an actual position value. The actual speed of the shaft can be determined by differentiation from the shaft position value measurements or by integration from shaft acceleration measurements. The measured or actual speed of the shaft can be supplied as an input signal to each feedback element. Each feedback element is specifically tuned to an oscillation frequency range of the shaft that is to be damped. The invention provides an easy and cost-effective way of damping mechanical oscillations that have limited frequency ranges.

Abstract: According to the invention, the controller cascades are suitably divided up and the oscillation damped only in the load rotational-speed controller. Here, a motor rotational-speed setpoint value (z) of a quickly regulated motor rotational-speed controller (9) and not the motor torque, is selected as the connection point for a load acceleration (i). In order to achieve a shorter transient response time, according the invention the difference between a setpoint rotational speed (x) and load rotational speed (y) is connected to the motor rotational-speed setpoint value (z). The solution in principle according to the invention which is presented has, in contrast to other known methods, the advantage that the actuation of the corresponding controllers is comparatively simple with very good control results.

Abstract: Circuits and methods for use with an integrated circuit chip having internal back EMF estimation to control a permanent magnet synchronous motor includes an AC current feedback circuit, a scaling circuit, and a current regulator. Additionally, a speed regulator may be employed. In one embodiment, during operation at very low speed, the speed regulator is in an open loop control mode due to a back EMF detection limitation of the IC chip, and only the current regulator is active. A feedback current signal, together with a user-defined command current signal, serves the input of the current regulator, which controls the AC motor current and drives the motor speed from standstill. Once the motor speed reaches a certain level, the measured back EMF from the IC chip is sufficient to estimate the motor speed, which is compared with a user-defined command speed, and an error of the these two signals provides the input of a speed regulator.

Abstract: A magnetic bearing system allows a movable body to be positioned to a point of substantial equilibrium in an axial direction after a system shutdown. A sensor measures the axial position of the movable body to produce an displacement output. That output is then adjusted to account for a sensor offset. The adjustment is stored and can be used to position the movable body during regular operation of the system or when the system reboots or restarts. The adjusted displacement output is converted into a force for positioning the movable body. The movable body may be a rotor in a heart pump apparatus.

Abstract: This invention describes a reconfigured form of the PID compensator such that the rate of change of the position error is inherently limited without affecting the performance of the servo loop when the position error is small. The technique described here maintains the performance of the conventional PID compensator when the position error is close to zero, which is the operating point of primary interest.

Abstract: An inverter part having a switching unit for applying a three-phase AC voltage to a motor, a lock detection unit for detecting a lock state of the motor and also generating a lock detection signal by the detection, and a current control unit for passing a d-shaft armature current id through the motor so that an absolute value of a current of a phase with the largest current flowing through the motor decreases based on the lock detection signal.

Abstract: A position control method for accurate position control of a driving source is disclosed. The method of the present invention comprises the steps of comparing a remaining driving amount of the driving source to a target position with a mechanical dead zone of a power transmission mechanism, controlling the position of the driving source by a proportional and derivative operation on a deviation of the position detected by the position detection circuit from a command position obtained from a speed command value while the remaining driving amount is larger than the mechanical dead zone, and controlling the position of the driving source by a proportional, integral, and derivative operation on the deviation of the position detected by the position detection circuit from the command position obtained from the speed command value when the remaining driving amount becomes smaller than the mechanical dead zone.

Abstract: Learning control is performed when carrying out processing by repeating instructions in a pattern cycle. Time/position converting means determines a positional deviation for a prescribed position with respect to a reference position, from the positional deviation determined by sampling, and the reference position output in synchronization with the drive of the servo motor. Corresponding correction data stored in the memory means is added to the positional deviation, and then the result is subjected to filtering processing to update the correction data corresponding to the position. Position/time converting means then determines correction data for the current sampling time, on the basis of the correction data corresponding to the position as stored in the memory means, and the detected reference position. This correction data is processed to compensate for dynamic properties, thereby deriving a correctional quantity, which is added to the positional deviation.

Abstract: An apparatus is provided for controlling a system to achieve a specified response. In one embodiment, the apparatus is a proportional, integrative, and derivative (PID) controller having a proportional element, an integrative element, and a derivative element coupled together. The elements respond to a reference signal and generate a control signal that causes a plant to generate a plant output. The proportional element has a gain element where the gain is a function of the ultimate gain of the plant (Ku) and the ultimate period of the plant (Tu). The controllers may also be embodied in non-PID controllers that share common elements, such as the use of: (a) Astrom-Hagglund controller output as an input for a subsequent controller; (b) internal feedback; and (c) a subsequent controller that performs a subtraction operation to generate the difference between the output of the Astrom-Hagglund controller and the output of the subsequent controller.

Abstract: An electric motor position control apparatus in accordance with the present invention has a plurality of sets of control parameters including at least the proportional gain of a position control section and the proportional gain of a speed control section beforehand, wherein set selection and the measurement of the response state of an electric motor to a position command at the time when the electric motor is controlled by using the control parameters of the selected set are carried out sequentially, one preferable set is selected depending on the measured response state, the control parameters of the selected set are set, and the control parameters are changed as a set.

Abstract: A control system includes a field oriented controller that receives a torque command and that generates phase voltages for an electric machine. A first transformation module receives stator terminal currents and generates d-axis and q-axis stationary frame currents. An open loop flux observer receives d-axis and q-axis stationary frame voltage commands and the d and q-axis stationary frame currents. The open loop flux observer includes a vector cross product calculator that generates an error signal that is proportional to an angular difference between an estimated stator flux and a computed stator flux and a proportional integral controller that generates an estimated rotor angular position based on the error signal. A second transformation module receives the d-axis and q-axis stationary frame currents and the estimated rotor angular position and generates d-axis and q-axis synchronous reference frame feedback currents that are output to the field oriented controller.

Abstract: Controlling a direct current motor driving an object by determining, if the object does not reach a target position, a reference velocity corresponding to a point of time from a predetermined velocity trajectory, obtaining a position of the object, calculating a current velocity of the object, and calculating a difference between the reference velocity and the current velocity. If the calculated difference is greater than a velocity error limit value, informing a user that an error has occurred.

Abstract: A method of conditioning a signal being communicated between a system to be controlled and a controller may include monitoring an actual output signal and conditioning the actual output signal. The method also includes determining the difference between the actual output signal and the condition signal and causing the actual output signal to be filtered based on the relationship between the difference between the actual output signal and the conditioned signal.

Abstract: Control of a motor in a device in which a mechanism is driven using the motor as the power source is achieved by providing velocity servo-control means for outputting first command information regarding the motor based upon a preset velocity profile and information relating to velocity of the mechanism, and position servo-control means for outputting second command information regarding the motor based upon a preset position profile and information relating to position of the mechanism. A motor driving signal is generated, based upon the first and second command information, in a region in which the mechanism is to be accelerated in the velocity profile. As a result, target-velocity attainment time is shortened and velocity fluctuation after attainment of the target velocity is reduced.

Abstract: A electric motor control device is provided for controlling an electric motor which actuates a movable member of a machine through a transmitting mechanism. When a torque command is given as motion command signal (9) to servo device (3), servo device (3) sends input torque signal (12) corresponding to motion command signal (9) to electric motor (5), which is energized. Movable member (7) is thus moved, producing vibrations. Servo device (3) outputs input torque signal (11) equivalent to input torque signal (12), and input torque signal (11) and rotational speed signal (10) are stored in memory device (2). Analyzing device (1) analyzes the frequencies of input torque signal (11) and rotational speed signal (10) according to an FFT, and outputs analytical result (14).

Abstract: An angle detector 25 detects a rotor angle &thgr; of a DC brushless motor 1 using a current value Iu_s detected by a U-phase current sensor 23 and a current value Iw_s detected by a W-phase current sensor 24 when high-frequency voltages vu, vv, vw for detecting a rotor angle are applied by a high-frequency adding unit 21. The high-frequency adding unit 21 determines the high-frequency voltages vu, vv, vw so that the direction of rotation of the motor 1 and the direction of a revolving magnetic field generated by the high-frequency voltages vu, vv, vw will be opposite to each other. A three-phase/dq converter 26 converts the current values Iw_s, Iu_s into a detected d-axis current Id_s and a detected q-axis current Iq_s using the rotor angle &thgr; detected by the angle detector 25.

Abstract: Apparatus, method and program for controlling electric motors to drive movable objects, wherein an input-rectifying device is operable, when a control signal to be applied to one of the electric motors requires the motor to be operated so as to operate the object in a direction opposite to a predetermined direction, to rectify the control signal so as to limit a motion of the object in the opposite direction, and a differential-control-quantity compensating device is operable after expiration of a predetermined time after a differential control quantity used together with proportional and integral control quantities to generate a control signal to be applied to another motor is updated on the basis of an error between a detected speed and a target speed of the object, so as to reduce the differential control quantity.

Abstract: A speed control apparatus of an AC motor a first subtracter 1 for finding toque component voltage saturation amount &Dgr;Vq from torque component voltage component Vq′ output from a torque component current controller 47a and torque component voltage command Vq* output from a torque component voltage limiter 54a, a first integrator 2 for holding the torque component voltage saturation amount &Dgr;Vq, a magnetic flux command corrector 3a for outputting magnetic flux command correction amount &Dgr;&phgr;2d from the held torque component voltage saturation amount &Dgr;Vq′ and rotation angular speed &ohgr; to Cartesian two-axis coordinates, and a second subtracter 4 for subtracting the magnetic flux command correction amount &Dgr;&phgr;2d from magnetic flux command &phgr;2d* and outputting magnetic flux correction command &phgr;2d*cmd.

Abstract: Control parameters are regulated without oscillating a servo control system. Respective control parameters P[p] (p=0, 1 - - - ), arranged in the order of gradually increasing a chance of oscillating the servo control system, are set sequentially starting with P[0], a torque command Tr or a fluctuation amount &sgr;, showing a variation in frequency component of vibration of a speed feedback amount &ohgr;, is determined for each of control parameters, and the servo control system is assumed to have reached an oscillation criticality when a fluctuation amount exceeds a specified value to thereby reset a control parameter set at that time to P[p−q] (q; natural number) or to P[0].

Abstract: A multivariable control method and system suitable for manipulating process variables based on observed changes in controlled objectives without extensive data analysis or involved model development. The method includes operating the process at an initial set of process variables and an initial set of controlled objectives, monitoring the set of process variables and the set of controlled objectives while continuously operating the process, adjusting one or more members of the set of process variables based upon a non-linear optimization with respect to a desired set of controlled objectives, and utilizing the monitored set of process variables and the monitored set of controlled objectives in the non-linear optimization.

Abstract: A predictive and self-tuning PI controller includes an apparatus for variably assigning gains thereto in accordance with specified time functions following a change in set-point. The control gains are computed in accordance with a plurality of input parameters and subsequently continuously adjusted to set-point errors based on a GPC approach thereby to optimize performance indices derived from simple and classical user specifications. Variation and tuning of control gains in accordance with set-point errors permits the PI controller to be useful in the general area of process control and applicable to a wider range of processes compared to traditional PI control, including time-delay processes, unstable processes and processes with time-varying dynamics.

Abstract: An ideal position is calculated based on an ideal servo system model, the difference between the calculated ideal position and the actual position feedback is multiplied by a predetermined gain only for a predetermined time from the direction reversing time of the ideal position, and the result is added to the speed command as the correction amount, so that variations in the correction effect, caused by the effect of a secular variation of the friction amount and the work condition difference is suppressed and even in a machine system with large elastic change in torsion of a ball screw, a seal material, etc., undercut caused by torsion restoration after the correction, etc., is suppressed and a servo system is prevented from becoming unstable.

Abstract: A controller (1) has a fuzzy calculation means (64) for performing a fuzzy calculation in order to calculate a PID value (P, I, D) based on a switch time T, a PID value (P1, I1, D1) before switching of the PID value, and a PID value (P2, I2, D2) after the switching. The switch time T is obtained by manual through the switch time input means (7) or by calculating it automatically. The PID value (P1, I1, D1) is stored in a PID value storage means (62), and the PID value (P2, I2, D2) is stored in a PID value storage means (63).

Abstract: A motor control method and apparatus produce rapid, point-to-point movement while minimizing settling time and peak power consumption in a servo-control system with a periodic input. Rapid open-loop movement is combined with tuning of the open-loop input based on position and velocity of the output when the loop is closed. Iterative learning control is used to adjust open-loop commands in subsequent cycles to reduce residual vibrations and quickly reach the desired final position. The apparatus and method can be used in motion control applications requiring rapid, periodic, point-to-point movement, such as weather satellite servo systems with a periodic input containing multiple step responses within each period.

Abstract: Controllers (PID1 to PIDn) perform control so that the controlled variables of first to n-th control loops may agree with their preset values. A step response progress calculating section (C_R1) calculates the progress &agr;1 of the step response of the first control loop where the variation of the controlled variable is the slowest. Control loop internal preset value calculating sections (C_S2 to C_Sn) correct the preset values of the second to n-th control loops according to the progress &agr;1 of the step response so that the controlled variables of the second to n-th control loops vary synchronously with the controlled variable of the first control loop and give the corrected preset values to the controllers (PID2 to PIDn).

Abstract: The present invention relates to a digital control circuit of the P.I. (Proportional Integral) type, receiving an error signal (Error) at an input terminal (IN1) and adapted to provide, at an output terminal (OUT1), a PWM [Pulse Width Modulated] output signal (PWM Output). The circuit is of a type comprising at least one analog-to-digital converter (100, 100*) connected to the input terminal (IN) and to the output terminal (OUT1) through at least one integrative/proportional branch (120, 121, 130, 134). Advantageously in this invention, the analog-to-digital converter (100, 100*) is an integration converter adapted to integrate the error signal (Error) before an analog-to-digital conversion thereof.

Abstract: A motor control system that determines a number of commutation values during each control cycle of the system. Determining a plurality of commutation values provides a system with a higher frequency of commutation updates without having to increase the speed of the control cycle. This allows for a smoother operation of a motor without having to increase the speed of the control system processor.

Abstract: An active control mechanism and method for stabilizing a servo-controlled actuator system such as an actuator system in a data recording disk drive by compensating the vibrational modes of the actuator's arm assembly. The control mechanism has a sensing arrangement which can include one or more individual sensors attached to the actuator at locations where they generate signals in phase with the vibrational modes, and especially with all the low-frequency major vibrational modes, of the arm assembly. A control mechanism derives from the signals an adjustment signal consisting of three corrective terms—a stiffening correction, an active damping correction, and an inertia correction by a phase correction. Furthermore, high-frequency out-of-phase modes can be stabilized by appropriately shifting the phase of the signals. The adjustment signal is used in the feedback control loop to stabilize the actuator system.

Abstract: A disk apparatus includes a DSP (digital signal processor), and a DSP core of the DSP receives a feedback input from a pick-up, and generates a focus control pulse and a tracking control pulse. That is, a focus servo loop and a tracking servo loop are formed. The DSP core detects a phase difference between a sine wave of a target frequency and a sine wave superposed on an input signal, and adjusts a gain of the servo loop so as to bring a DC component of a correlation signal correlated with the phase difference to a 0 level. More specifically, if the DC component of the correlation signal exceeds a predetermined threshold value, an adjusting amount of the gain is rendered large, and greatly brought closer to the 0 level. On the other hand, if the DC component of the correlation signal is equal to or less than the predetermined threshold value, the adjusting amount of the gain is rendered small, and gradually brought to the 0 level.

Abstract: An integral term component generating unit 21 integrates a d-axis current difference &Dgr;Id and a q-axis current difference &Dgr;Iq using an integral gain Ki which is determined to stabilize a system where the d-axis current difference &Dgr;Id and the q-axis current difference &Dgr;Iq are multiplied by the integral gain Ki, integrated, and inputted, with respect to a steady gain M which approximates, including proportional gains Kp, the steady input-to-output relationship of a motor 2 to which the voltage applied to a d-axis armature and the voltage applied to a q-axis armature are inputted and from which the current flowing through the d-axis armature and the current flowing through the q-axis armature are outputted, thereby a d-axis integral term component Vd_i which is an integral term component of a d-axis command voltage Vd_c and a q-axis integral term component Vq_i which is an integral term component of a q-axis command voltage Vq_c are generated.

Abstract: A disturbance compensation control system which restricts periodic disturbance of a control object such as a motor includes a repetition control unit. The repetition control unit restricts the periodic disturbance to the control object. The repetition control unit is designed so as not to perform a repetition compensation control when the control object is initially started.

Abstract: A system and method for adaptively designing self-tuning controllers, specifically PID controllers for process control systems. The method is based on a model-parameter interpolation, according to which a candidate process model is defined by a predetermined, limited set of models. Each of the models is characterized by a plurality of parameters, and, for each model, each of the parameters has a respective value that is selected from a set of predetermined initialization values corresponding to the parameter. Evaluation of each of the models includes computation of a model squared error and computation of a Norm that is derived from the model square errors calculated for the models. The Norm value is assigned to every parameter value represented in the model that is represented in an evaluation scan. As repeated evaluations of models are conducted, an accumulated Norm is calculated for each parameter value.

Abstract: An improved method for controlling a servomechanism, applicable to nearly all types of servomechanism control systems. The inventive method improves the performance of servomechanism control systems which utilize a digital feedback sensor by enabling the gain to be varied. The variable gain allowed by the inventive method enables tighter control, and better performance.

Abstract: For controlling multivariable systems, a control unit for controlling a system with several coupled control variables. The control unit includes controllers (10, 11) having associated control variables (x1, x2) as well as a decoupling network. The decoupling network is connected upstream from the system and includes at least one first decoupling member (12). A first output variable (y1) of a first one of the controllers (10) is routed to the first decoupling member (12). The first decoupling member generates a first correcting quantity (14) for a second output variable (y2) of a second one of the controllers (11). The second controller (11) has a PI- or PID-controller core (40) and is configured such that integrator windup is eliminated when the second output variable (y2) corrected with the first correcting quantity (14) reaches a manipulated variable limit. Bumpless manual/automatic changeover of the controller is also made possible.