Abstract: An information processing apparatus communicates with a storage device and includes a serial interface configured to support plural link rates, and a controller. The controller retrieves from the storage device via the serial interface information indicating a relationship between maximum power consumption and power consumption efficiency value for each link rate in a first power throttling mode that gives priority to performance and a second power throttling mode that gives priority to reduction of peak power, the power consumption efficiency value being a value that corresponds to the number of I/Os per watt, select the first or the second power throttling mode based on the retrieved information and a mode specified from one of three modes, and instruct the storage device to limit power consumption based on the selected power throttling mode.

Abstract: An electric machine assembly with fail-safe arrangement is described. The assembly comprises a stator including a plurality of windings and a cooperating rotor including at least one permanent magnet; a detector configured to detect DC current in at least one of the windings of the stator; and a bypass circuit configured to be activated upon detection of the DC current by the detector and to prevent at least some of the DC current from flowing into the at least one of the windings of the stator.

Abstract: A circuit for controlling a load current through a coil is connected to an output port of a transistor H-bridge that includes two low side transistors and two high side transistors. A current sense circuit is coupled to the H-bridge and configured to provide a representation of the load current provided by the output port. A current regulator is configured to generate a modulated signal dependent on the representation of the load current and a current set-point. The modulated signal has a duty-cycle. A gate control logic drives the individual transistors of the H-bridge on and off in accordance with the modulated signal. A direction signal provides the load current to the coil. The direction signal determines the direction of the load current. An over current detection circuit is coupled to each individual transistor and is configured to signal an over-current by providing an active over-current failure signal when a transistor current through the respective transistor exceeds a respective maximum value.

Abstract: The present invention relates to a method of controlling the speed of rotation of a piezoelectric motor comprising at least one step of determining the variation of the speed of rotation as a function of the frequency of the excitation voltages of the piezoelectric motor for the actual temperature of the piezoelectric material.

Abstract: Both a method and a use by this method of an apparatus for detecting blocking of a direct current motor (10), in particular a direct current motor (10) for a blower of a motor vehicle, is presented. The direct current motor (10) is deactivated by a computer unit (20) with the aid of a switching means (18) for a defined time period (Toff). Within the defined time period (Toff), at least one subsequent time (ta, tb), an induced voltage (U) of the direct current motor (10) is measured and forwarded to the computer unit (20). The direct current motor (10) remains deactivated if the induced voltage (U) undershoots a predetermined threshold value (Uth), or the direct current motor (10) is reactivated if the induced voltage (U) of the direct current motor (10) does not undershoot the predetermined threshold value (Uth).

Abstract: A motor control method includes the steps of: measuring a time period from an output of a drive detection signal to a next output of a drive detection signal; storing the measurement result at each time of output of a drive detection signal as a measured cycle; calculating a driven velocity of the driven object based on the stored measured cycle; calculating an operation amount of the motor such that the calculated driven velocity is equal to a predetermined target velocity. In the motor control method, it is determined, at each calculation timing, whether or not the driven object is in a low velocity state where an actual velocity is lower than the target velocity. When determined affirmative, calculation of the driven velocity of the driven object is performed based on a measured value being currently measured at the calculation timing in place of the stored measured cycle.

Abstract: The present invention provides a fan that has a fan motor and two signal lines including a number-of-rotations switching control signal line and a rotational state outputting signal line, makes the fan motor rotate at a number of rotations determined by a number-of-rotations switching control signal input via the number-of-rotations switching control signal line, outputs the rotational state of the fan motor via the rotational state outputting signal line, and can provide notification of detail data without increasing the number of signal lines. The fan retains data in the data storage section in a non-volatile manner and outputs the data via the conventionally existing rotational state outputting signal line.

Abstract: Both a method and a use by this method of an apparatus for detecting blocking of a direct current motor (10), in particular a direct current motor (10) for a blower of a motor vehicle, is presented. The direct current motor (10) is deactivated by a computer unit (20) with the aid of a switching means (18) for a defined time period (Toff). Within the defined time period (Toff), at least one subsequent time (ta, tb), an induced voltage (U) of the direct current motor (10) is measured and forwarded to the computer unit (20). The direct current motor (10) remains deactivated if the induced voltage (U) undershoots a predetermined threshold value (Uth), or the direct current motor (10) is reactivated if the induced voltage (U) of the direct current motor (10) does not undershoot the predetermined threshold value (Uth).

Abstract: A method and apparatus for use with a motor controller that receives a command velocity and that applies voltages to drive a motor at the command velocity, the apparatus comprising a dual inertia lost motion assembly including a motor and a load couplable to the motor, the lost motion assembly characterized by at least some lost motion between the motor and the load, the motor and load together characterized by a total assembly inertia, an acceleration error determiner for generating an acceleration error that is the difference between a derivative of the command velocity and a motor acceleration value and a low pass acceleration error filter filtering the acceleration error and having a gain set as a percentage of the total assembly inertia, the acceleration error filter providing the filtered signal to the controller, the controller using the filtered signal to adjust the applied voltages.

Abstract: A machine tool has a spindle with a tooling body mounted thereon, a detector for detecting an acceleration time for the tooling body to reach from a rotation start to a predetermined rpm, a controller for controlling an rpm of the spindle under a lowered limit when the acceleration time is longer than a reference time. Another detector detects an asymmetricity of radial forces acting on the spindle, and the controller controls the rpm of the spindle under a lowered limit when the asymmetricity of radial forces exceeds a reference degree.

Abstract: A motor rotational speed control apparatus is constructed by a control unit for performing an instruction to accelerate a rotational speed of a motor, an instruction to decelerate, or an instruction to maintain a rotational speed, a driving unit for driving the motor in accordance with an instruction outputted from the control unit, and first and second wires for transferring the instruction of the control unit to the driving unit. The control unit shows the instruction by a combination of signal levels of a first signal and a second signal and transmits the first and second signals to the driving unit through the first and second wires, and the driving unit drives the motor in accordance with the combination of the signal levels of the first and second signals.

Abstract: A disk drive system for use in limited power applications is disclosed. The disk drive includes a spindle motor having two or more windings, along with a spindle motor driver which can drive the spindle motor in any of a unipolar, bipolar or tripolar mode. The bipolar or tripolar mode is used to start the disk drive and then the unipolar mode is used to operate the disk drive while data is being retrieved. By combining the three drive modes a large start current reduction and higher rotation velocities are achieved. Current consumption is further minimized by adaptively transitioning from bipolar to unipolar modes of operation. The disclosure also includes a general methodology for optimal motor K.sub.E and K.sub.M parameter selection.

Abstract: A computer having a hard disk drive includes a battery voltage monitor which establishes a shut down condition of the computer if the supply voltage falls below a chosen level V.sub.L. Upon start up of the hard disk drive motor, current through the motor is limited so that supply voltage of the battery to a computer does not fall below level V.sub.1, which level is greater than the level V.sub.L. Additionally during start up, current in the motor is controlled so that voltage supplied by the battery to the computer does not rise above a threshold level V.sub.2 which is greater than V.sub.1.

Abstract: The servo amplifier is used for driving power transistors supplying current to a D.C. servo motor. The servo amplifier includes a control signal input; a tach signal input; circuitry coupled to the inputs for creating an error signal between the control signal and the tach signal; a triangular wave generator for generating a triangular wave form; a summing network for summing the error signal with the triangular wave; a modulator for modulating the resultanat signal; tri-state drive logic circuitry; and power transistor drive circuitry adapted to be coupled to the power transistors. The triangular wave modulator is coupled to the output of the summing network for supplying modulated signals to the tri-state drive logic circuitry and the drive logic circuitry having outputs coupled to the drive circuitry. The tri-state drive logic circuitry provides fast response to the error signals indicating a desired change in speed of the D.C. motor, and without over-shoot or hunting of the D.C. servo motor.

Abstract: A device for driving a motor-operated closure part for an opening, especially on a motor vehicle, having a protective circuit for interrupting the closing movement when there is an indication that an object may be obstructing closure of the opening. A speed transmitting means exists that detects the adjusting speed of the closing part on at least one range of the adjusting path of the closure part that is critical with respect to the engagement of an obstruction. In addition, an evaluating stage is provided that responds to the speed signal and/or its rate of change with respect to time, for producing an obstruction signal that activates a control means of the circuit to interrupt the closing movement.

Abstract: A DC motor control system which has means for detecting the rise and fall of a drive command signal to generate an ON ACCELERATION/DECELERATION signal and means for generating a current limit signal for driving a DC motor by the ON ACCELERATION/DECELERATION signal to produce a rated output and for driving the DC motor to produce an output 1/n times the rated output when the DC motor is switched from an acceleration state to a stationary state. When the DC motor is accelerated or decelerated by the drive command signal, a current for obtaining the rated output is applied to the armature of the DC motor and, in the stationary state, even when a load on the DC motor is maximum a current for obtaining an output 1/n times the rated output is applied to the armature of the DC motor to reduce the output of the large-output DC motor, thereby providing an enlarged constant output DC motor range.

Abstract: A separately excited constant load DC electric motor is controlled in resse to a source of current for the desired motor speed. Current from the source applied to the motor armature is modified by a motor loss simulator circuit responsive to the source. The circuit simulates the losses the motor is expected to have in response to the current derived from the source, whereby the actual motor speed corresponds with the desired motor speed despite the loss. The losses are simulated during acceleration and deceleration as well as steady state intervals of the current source, which can be actuated to drive the motor in both directions.

Abstract: A method and apparatus are disclosed for reducing effective inductance and providing balanced line-to-line voltages in induction machine dynamic braking circuits which utilize braking resistors to substantially increase the full torque braking range of the machine. The current phase lag caused by the inductive property of conventional braking resistors, is substantially reduced by rectifying the current provided to the braking resistor through a three-phase rectifier bridge. This reduction of the current phase lag permits a reduction in the capacitance required to compensate for the effective inductance in the dynamic braking circuit. Furthermore, because the braking currents flow through a common braking resistor, the line-to-line stator motor voltages are inherently balanced. If the prior art braking impedance control is also employed, the rectifier bridge need carry current only if dynamic braking is required when motor voltage is greater than the maximum voltage of the inverter supplying the machine.

Abstract: A d.c. motor control system includes a pair of armature windings mounted on a single rotor or on a pair of mechanically coupled rotors, and a field winding or windings. The system includes switch means operable to effect a change in the electrical connections of the armature windings to a pair of electrical supply terminals and means for effecting variations of the current flowing in the field winding or windings.