Abstract: An electric drive control apparatus for an electric machine, includes a controller that computes an instruction value based on an electric machine rotational speed and a target electric machine torque that represents a target value of an electric machine torque, generates a drive signal based on the instruction value, computes a voltage saturation variable that represents a likelihood of an occurrence of a voltage saturation, determines whether a switch condition for switching a control between an asynchronous PWM control and a synchronous PWM control is met based on the voltage saturation variable, and selects and outputs the drive signal and switches the control between the asynchronous PWM control and the synchronous PWM control based on a determination as to the switch condition.

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 region judging circuit judges an electric angle region of a three-phase brushless DC motor based on an output signal of a resolver. A latch timing output circuit determines an optimum latch timing. A driving direction judging circuit judges a rotational direction of the motor based on a comparison in largeness between a pair of phase currents. A latch circuit latches a judgement result of the driving direction judging circuit at the latch timing designated by the latch timing output circuit and retains the judgement result until the next latch timing comes.

Abstract: A starting system for a pump includes a driving motor, an electric source, a selector switch, a starter sensor, a temperature sensor and a control unit. The selector switch is located between the driving motor and the electric source for reversing polarity of the electric power supplied from the electric source to the driving motor. The starter sensor senses whether or not the driving motor has been started. The temperature sensor senses a temperature. The control unit operates the selector switch so as to repeatedly give the driving motor indications of reverse rotation and normal rotation in a case where the starter sensor does not sense that the driving motor has been started even if the control unit operates the selector switch so as to give the driving motor the indication of normal rotation in a state where the temperature sensed by the temperature sensor is below a preset temperature.

Abstract: A method for detecting a state of an electric motor includes: energizing the motor with electrical power such that an associated current applied to the electric motor rises over time toward a reference level; determining an amount of time that elapses between when the motor is energized and the reference level is reached; and, evaluating a state of the motor based upon the determined amount of time.

Abstract: A motor control system for use in heating, ventilation and air conditioning applications including a blower and a motor coupled to drive the blower, an inverter coupled to provide energization to the motor, a relay capable of coupling the motor to the output of the inverter or to line power, and a controller providing signals to control the output of the inverter, where, upon startup and transfer of the motor from the line to the inverter, the output of the inverter is controlled by the inverter to provide for an enhanced startup or transfer.

Abstract: The present invention is a control apparatus for controlling an electric power steering system having steering assist force control means for controlling a motor that gives a steering assist force to a steering mechanism relying upon a main torque input value obtained by subjecting a main torque signal from a torque sensor to the A/D conversion, upon a gain-multiplied torque input value obtained by multiplying said main torque signal by a first gain times followed by the A/D conversion and upon a sub-torque signal from said torque sensor, in order to carry out a failsafe function, characterized by the provision of a gain multiplier for multiplying said main torque input value by a second gain times,. and switching means for changing the output of said gain multiplier and said gain-multiplied torque input value over to each other to input it to said steering assist force control means.

Abstract: The invention concerns a method for controlling an electric motor driving a body in translation between an initial position and a final position determined by a stop, by powering the motor with reduced voltage in the final position approach phase. The motor has a torque/speed characteristic such that the torque at null speed decreases with the supply voltage. As the approach phase starts, the method consists in determining a reduced voltage by decreasing the rotational speed of the motor from a nominal value to a predetermined reduced value and in cutting the motor power supply if the motor rotational speed drops below a predetermined threshold value.

Abstract: A controller PWM control an opening and closing motor (16) of an opening and closing means, increases a duty ratio of the PWM control according to a given increasing rate just after starting the opening and closing motor (16), reducing the duty ratio to a given value by detecting a start of the open close body, and keeping the given value of the duty ratio for a given period.

Abstract: Method and apparatus for operating a motor. During a commutation state current is applied to a motor while field effect transistors (FETs) are held in an enable or disable state to effect current in phases of the motor. The phases have a high FET and a low FET. Control circuitry is employed to detect back electromotive force and zero crossing (Zc) signals that indicate transition timing for the commutation states. At a transition state the current is decreased in accordance with a noninstaneous decay function and applying a pulse width modulated signal to a switching element. Alternatively, the current is decreased by enabling either all low side FETs or all high side FETs to allow the current to decay. The next commutation state is applied after the current has been reduced, avoiding negative current to be source from ground and reducing current spikes in the motor.

Abstract: Systems, methods, and apparatus, consistent with principles of the present invention, allow an unmodified device, for example, a dc starter motor, that normally operates at a first voltage to function in an electrical system providing a second voltage, which is different from the first voltage, and received from the power source. A device actuator, such as a solenoid, is controlled using the second voltage. The first voltage is produced and supplied to the device in response to a first action of the actuator, for example, upon solenoid depression. This voltage is then inhibited from being provided to the device in response to a second action of the actuator, for example, upon solenoid retraction after engine cranking.

Abstract: Electronic device for controlling a synchronous motor with permanent-magnet rotor, comprising an alternating voltage current source at mains frequency connected in series with said synchronous motor (1), at least one static switch (2) connected in series with said synchronous motor (1), and an electronic circuit (3) that acts on said static switch (2). Said electronic circuit (3) determines the timing for the firing of the static switch (2) taking as reference the zero-crossing of the mains voltage (Vr) and applying a firing time (Td) starting from said reference, said firing time (Td) being obtained as a function of the position of the rotor (1A) of the motor (1) in the previous half-cycles.

Abstract: A method and apparatus for controlling the operation of a garage door opener is disclosed wherein a micro-controller de-energizes a garage door drive motor for a first period when a stop command is received while the garage door drive motor is energized and the garage door is travelling in a first direction. The micro-controller then energizes the drive motor to move the garage door in the opposite direction from the first direction for a second period. The micro-controller then de-energizes the drive motor, placing the door in a static state.

Abstract: A load indicator for an electric motor, comprising a first means (II, IU, CPU) for repeated determination of the motor load, a second means (CPU) for comparing the current motor load, as determined by the first means, with a preset load limit, and a third means (CPU), PP) for indicating that the current motor load exceeds the load limit. Moreover, a meant (T, CPU) is arranged to initiate a presetting of the load limit. This means is adapted to be actuated, when the motor runs in normal operation, for presetting of the load limit as the current motor load changed by a predetermined deviation value stored in the load indicator.

Abstract: The invention relates to a method for taking up play in a drive system when a change in load occurs. The drive system comprises a drive engine, preferably an internal combustion engine, coupled to a drive line in a vehicle, an electric motor which acts on the drive engine and/or the drive line with a driving or braking torque, and which motor is coupled to the drive engine or constitutes a part of the drive line, and a control system for controlling the electric motor. The control system sends a pulse to the electric motor when a change in load occurs, a torque pulse taking up play in the drive line before a torque stage from the drive engine begins. The size of the pulse is selected from a matrix stored in a memory, depending on the current operating conditions. The invention also relates to an arrangement for implementing the method.

Abstract: A method for determining the position of an element driven along a travel segment by a shaft of a motor includes counting current ripples detected in an armature current signal of the motor as the motor shaft rotates to drive the element. A first time interval between when the motor is turned on with power being supplied to the motor and when the first current ripple is detected is determined. A second time interval between when the last current ripple is detected after the motor has been turned off with the power supplied to the motor being interrupted and when the motor shaft stops rotating is determined. First and second current ripple components corresponding to the first and time intervals, respectively, are estimated. The position of the element along the travel segment is determined based on the counted current ripples and the estimated first and second current ripple components.

Abstract: A method of detecting a rotor condition of a dc motor is provided. The motor 14 is part of a motor control circuit 10 having a free-wheeling diode 20 in parallel with the motor 14. The method establishes a threshold voltage for back emf voltage evaluation. The motor is energized to operate at a certain speed. Current is cut-off to the motor via a switch 16 for a time sufficient for current through the free-wheeling diode to decay to zero. The back emf voltage detected at leads of the motor is then compared via a comparator 21 to the threshold voltage.

Abstract: A method controls an electric vehicle which is so constituted as to drive a synchronous motor by way of a switch and an inverter circuit. A battery acts as a source of driving a controlling power. The synchronous motor has a permanent magnet acting as an outer rotor. The method includes the following operations of: 1) detecting that the electric vehicle has an acceleration signal of zero; 2) detecting that an actual speed of the electric vehicle is less than a predetermined percent of a rated speed; 3) supplying a current to a winding of a fixed phase of the synchronous motor, by way of the inverter circuit; and 4) generating a braking force.

Abstract: Brake mode switching signal production means detects the number of revolutions per unit time of a rotor according to a change in a positional relationship between motor windings of a plurality of phases and the rotor so as to output first and second brake mode switching signals for selecting either a short brake mode or a reverse brake mode for braking the rotation of the rotor based on the number of revolutions. Control means outputs an energization control signal for controlling energization of the motor windings of a plurality of phases in response to the first and second brake mode switching signals. Thus, it is possible to reduce the braking noise and the stopping time.

Abstract: A method and a device for controlling a winder, where the winding torque (Tw), during winding, is controlled as a function of the desired tractive force in the material to be wound. During winding, repeatedly is calculated which value a quantity (Vl), influencing the winding torque (Tw), has to adopt in order to obtain a desired tractive force (Fw), and an adjustment of the said quantity (V1) is carried out, the calculated value being used as an objective value. Preferably, the calculation is done by an algorithm, expressing the said quantity as a function of the desired tractive force (Fw), as a function of one or more fixed parameters which are characteristic for winding up material or for the winder, and as a function of one or more variable parameters, being measured or calculated during winding. The device also relates to a winder comprising a winding body (1), (2) for winding a material, a drive device (3,9),(4,10) for driving this winding body (1), (2) an a control device.

Abstract: A brushless dc motor mainly comprises a stator, a first Hall sensor, a second Hall sensor, and a rotor. The stator, which comprises a plurality of magnet poles, is axially combined with the rotor which comprises a driver permanent magnet and a frequency permanent magnet. The driver permanent magnet is adapted to rotate the rotor by means of being detected by the first Hall sensor while the frequency permanent magnet with predetermined pole count adapted to generate the rotational frequency of the rotor by means of being detected by the second Hall sensor.

Abstract: A position sensor emulator system and method for use in the control of synchronous machines are disclosed. The position sensor emulator system (220) includes a first bandpass filter (222) that filters phase voltage signals from a stator of a synchronous machine (230). A converter (224) that converts the filtered phase voltages into balanced two-phase quadrature signals. A rectifier (226) that rectifies exciter voltage signals of the synchronous machine (230) and a second bandpass filter (228) that filters the rectified exciter voltage signals to generate a reference signal.

Abstract: A magnitude of current that does not cause electric power generation is supplied to a field winding of a movable element, and an induced voltage generated in a armature winding of a stationary element is measured. A position of the movable element is determined from the measured induced voltage. In addition to the thus-determined position of the movable element, a position of the movable element measured on a different basis is used to measure an error regarding the position of the movable element.

Abstract: The invention concerns a device for stopping the motor when the load on the motor exceeds a predetermined value. It comprises means (D1, DZ, R1, R2) transforming the voltage variation at the phase-shifting capacitor terminals corresponding to a specific torque variation into a selected voltage variation whatever the maximum torque developed, means comparing (T1) the transformed voltage (UB) with a reference voltage and means for stopping the motor when the transformed voltage is less than the reference voltage.

Abstract: An appliance includes a rotating position switch and a selector switch. The rotating position switch has a first position associated with a first appliance function and a second position associated with a second appliance function. The second appliance function modifies the first appliance function. The selector switch has an actuated state configured to generate a signal representative of a selection of the first appliance function when the rotating position switch is in the first position. The actuated state is further configured to generate a signal representative of a selection of the second appliance function when the rotating position switch is in the second position.

Abstract: An abnormality detector for motor drive system easily detects, using a CPU, abnormality such as short circuit or disconnection in magnetic field coils of a motor, wiring, an open/close element, etc., which are controlled by a microprocessor (CPU). The open/close elements conducting an open/close operation sequentially in response to pulse outputs P1, P2 generated by the CPU, drive the magnetic field coils. Surge voltages generated upon interrupting the mentioned open/close elements are OR connected through a diode, and input to a temporary storage circuit. Then the CPU reads out, stores and resets the surge voltages using pulse edges of the pulse output P1 or P2. When any generation of the surge voltage is not stored in the temporary storage circuit, the CPU operates an abnormality alarm display.

Abstract: Method and system for controlling a permanent magnet machine are provided. The method provides a sensor assembly for sensing rotor sector position relative to a plurality of angular sectors. The method allows starting the machine in a brushless direct current mode of operation using a calculated initial rotor position based on angular sector position information from the sensor assembly. Upon reaching a predefined mode-crossover criterion, the method allows switching to a sinusoidal mode of operation using rotor angle position based on extrapolating angular sector position information from the sensor assembly.

Abstract: A method of starting an electric brushless rotating machine is provided where a large startup torque is obtained with no use of any rotor position detecting device and the forced commutation can be switched to normal energization easily and smoothly. At the startup stage, any two of three-phase stator windings are energized for initial magnetization (Steps S1 and S2) to hold the magnetic rotor at a position. Then, the windings of the phases are energized in a sequence while gradually increasing the level of the energization (Step S3). During the forced commutation, the magnetic rotor is rotated by a rotating position detecting signal generated from a voltage signal induced on the not-energized windings to drive the output shaft of an engine. Then, the energization is canceled when the number of revolutions in the internal combustion engine determined from the rotating position detecting signal reaches its predetermined level.

Abstract: A load-driving circuit capable of driving a plurality of loads based on a priority order endowed therewith is provided. The load-driving circuit comprises a first load 3, a first driving switch 1 for driving the first load, a second load 4, a second driving switch 2 for driving the second load, first switching means 5 being turned on when the first driving switch is switched to a position where the first load is driven, second switching means 6 being turned on when the second driving switch is switched to a position where the second load is driven, and third switching means 7 for disconnecting the first load from the grounding terminal when the first switching means 5 and the second switching means 6 are turned on at the same time.

Abstract: A rotor position estimator for a permanent magnet motor with a stator and a rotor includes a sensing circuit that generates d-axis and q-axis negative sequence stationary current (NSSC) signals. A signal conditioning circuit combines the d-axis and q-axis NSSC signals with first and second positive feedback signals that are based on a rotor position estimate signal. A regulator is coupled to an output of the signal conditioning circuit. A mechanical system simulator that is coupled to the regulator and a demand torque signal generates the rotor position estimate signal. The signal conditioning circuit includes a second harmonic amplifying circuit that receives the rotor position estimate signal and outputs the first feedback signal to a first multiplier. The signal conditioning circuit includes an inverse saliency model receives the rotor position estimate signal and outputs the second feedback signal to a second multiplier.

Abstract: In an AC motor having a main winding connectable to an AC power source for supplying running torque, and having a start winding connectable to the AC power source for supplying starting torque, a start switch is provided for connecting and disconnecting the start winding from the AC power source in starting and running modes, respectively. A main winding voltage phase detector detects the phase of voltage across the main winding. A start winding current phase detector detects the phase of current through the start winding during the starting mode. A cut-out circuit responds to the main winding voltage phase detector and to the start winding current phase detector.

Abstract: A motor controller system (15a) for dc power source motors (10) which includes a sensor device (16) that operates to measure and generate a voltage signal from the motor current and the rate of change of said current, and a programmable input/output processor (12) which receives voltage signals as input from the motor current, dc power source (11) and/or motor (10) and compares on or more of these voltage signals to one or more control parameters. Based upon these comparisons, the processor (12) generates a pulse width modulation control signal, which triggers a switching mechanism (14) and related interrupt service routing to make adjustments to the operational parameters of the motor by periodic interruption of the motor current.

Abstract: A dual current-limiting circuit for a dc brushless motor includes an over-current detective circuit, an operation detective circuit, and a current-limiting circuit. The over-current detective circuit produces a voltage signal used to determine whether an over-current has been input to the motor. The operation detective circuit also produces a voltage signal used to determine whether the motor is being operated in a normal manner. The current-limiting circuit decides to turn on a first switch of a first current-limiting circuit and to subsequently turn on a second switch of a second current-limiting circuit depending upon the two voltage signals. The current-limiting circuit is capable of suppressing current passing through a coil at a low voltage level, which is inadequate to damage a driver circuit and still adequate to restart the motor if an abnormal input current is eliminated.

Abstract: Control section determines necessary acceleration of a transporting section in accordance with an actual transporting speed, and also determines a correction coefficient corresponding to the number of rotations of an engine from among correction coefficients having a characteristic of becoming closer to a value of one as the number of rotations of the engine increases. The control section multiplies the necessary acceleration by the correction coefficient to thereby provide corrected necessary acceleration, and controls rotation of a transporting drive motor in accordance with the corrected necessary acceleration. When the amount of electric power to be generated by a power generator driven by the engine has increased, the control section controls the opening of a throttle valve.

Abstract: A motor control system for use in heating, ventilation and air conditioning applications including a blower and a motor coupled to drive the blower, an inverter coupled to provide energization to the motor, a relay capable of coupling the motor to the output of the inverter or to line power, and a controller providing signals to control the output of the inverter, where, upon startup and transfer of the motor from the line to the inverter, the output of the inverter is controlled by the inverter to provide for an enhanced startup or transfer.

Abstract: An electronically commutatable motor, whose excitation windings are controllable via semiconductor output stages by an electronic control unit with the aid of PWM control signals, a setpoint value being specifiable to the control unit, and the control unit emitting corresponding PWM control signals to the semiconductor output stages; a motor characteristic curve, from which an assigned nominal operating speed is derivable for the setpoint value being stored in the control unit, and the derived nominal operating speed being able to be compared to the actual speed of the motor. It a predefinable or predefined speed difference between the nominal operating speed and the actual speed is exceeded, the control unit and/or the semiconductor output stages can be switched off. The derivation of the nominal operating speed for the predefined setpoint value is facilitated by a three-dimensional characteristics field determined by four coordinate points.

Abstract: The invention concerns a method for controlling a motor vehicle wiper motor comprising steps which consist in: determining at least a range related to an operating parameter of the motor and capable of having several non null values; comparing said range with a predetermined threshold (high LS, low; HS, high INT, low LS, low INT); and controlling the motor on the basis of the result of the comparison. The range is determined when the rotor of the motor occupies a determining position corresponding to a predetermined point on a trajectory of a blade driven by the motor.

Abstract: An electronically commutatable motor, whose excitation windings are controllable via semiconductor output stages by an electronic control unit with the aid of PWM control signals, a setpoint value being specifiable to the control unit, and the control unit emitting corresponding PWM control signals to the semiconductor output stages. The start-up of the motor is monitored in a simple manner and an overloading is prevented in that, with the input of the setpoint value and/or the switching on of the control unit and/or the semiconductor output stages, after a predefined or predefinable starting time has expired, a monitoring device monitors the speed of the motor to check whether a minimum speed has been reached, and if the minimum speed is not reached, the control unit and/or the semiconductor output stages is/are disconnectible.

Abstract: A synchronous motor drive system in accordance with the present invention detects a DC current of an inverter which drives a synchronous motor, and based on the magnitude of the current, estimates torque current components that flow through the motor, and then based on the estimated value, determines the voltage which is applied to the motor, and finally estimates and computes the magnetic pole axis located inside the motor using the estimated value of the torque current.

Abstract: The present invention provides a motor control device, which comprises a signal control circuit having an input pin to output different motor drive signals according to input electronic signals. The signal control circuit is also protected for over current and over voltage. Two switch circuits of brake before make configuration are connected to the signal control circuit. An inverter is arranged between the two switch circuits. The inverter switches the motor drive signal among the two switch circuits and transmits it to a driver, which is connected to a motor drive circuit. A power source circuit is connected to the motor drive circuit to provide electricity for the motor drive circuit. A back electromotive force (back EMF) component for detection and control of the rotation speed of motor is disposed in the driver. The motor control device of the present invention has the advantages of reduced number of pins and shrunk volume.

Abstract: A starting motor for an internal combustion engine, where a control circuit monitors or controls the temperature of the starting motor or the carbon brushes, and if necessary, limits or switches off the primary current. The temperature is indirectly determined by means of a comparison, using the voltage ripple in the primary circuit between the battery and the starting motor. Occurring errors can be stored as status messages in an error storage device, and if desired, they can be interrogated and corrected at the next service interval.

Abstract: A method for determining the position of a movable element driven by a motor shaft includes using a counter to count current ripples contained in an armature current signal of the motor as the motor shaft rotates to drive the element. The position of the element is determined based on the counted current ripples. Upon power to the motor being interrupted such that the motor shaft slows down during the power interruption and upon the counter being prevented from counting the current ripples contained in the armature current signal of the motor during the slowdown of the motor shaft, an amount of current ripples expected to be contained in the armature current signal of the motor during the slowdown of the motor shaft is estimated. The position of the element during the slowdown of the motor shaft is determined based on the estimated amount of current ripples.

Abstract: A starter control system is comprised of a starter motor, a control circuit for controlling the starter motor to rotate at a preliminary rotation speed that is high enough to engage a pinion with an engine for a predetermined time and low enough to suppress a harsh noise caused when the pinion engages the engine and, thereafter, at a normal rotation speed that is high enough to start the engine, and a control circuit for changing the preliminary rotation speed according to an engine temperature. The starter control system is effective to reduce noises that are caused when the engine is started by an economy-run system.

Abstract: A brushless motor apparatus includes a motor section including delta-connected three-phase coils; a switching section electrically connected to the motor section via a line; and a driving section for controlling an ON state and an OFF state of the switching section so as to drive the motor section. In the brushless motor apparatus, r1+r2<2R, where r1 is an internal resistance of the switching section in an ON state, r2 is a resistance of the line connecting the motor section and the switching section, and R is a direct current resistance of each of the three-phase coils.

Abstract: Method and system for controlling a permanent magnet machine are provided. The method provides a sensor assembly for sensing rotor sector position relative to a plurality of angular sectors. The method further provides a sensor for sensing angular increments in rotor position. The method allows starting the machine in a brushless direct current mode of operation using a calculated initial rotor position based on an initial angular sector position information from the sensor assembly. Upon determining a transition from the initial angular sector to the next angular sector, the method allows switching to a sinusoidal mode of operation using rotor position based on rotor position information from the incremental sensor.

Abstract: A system and method is disclosed for drilling a borehole using a silicon controlled rectifier (SCR) system. The SCR system includes analog rack mounted hardware cards for control of an engine AC generator and a DC load. The engine AC generator of the SCR system generates alternating current (AC) that is then converted to direct current (DC) by a silicon controlled rectifier transformer connected to the output of the engine AC generator. The DC power from the silicon controlled rectifier transformer drives one or more DC motors that are coupled to a load by a mechanical linkage. An AC generator controller controls the engine AC generator and includes an engine control module that controls operating speed of the engine AC generator and air-fuel mixture at engine start. A DC load controller coupled to the silicon controlled rectifier transformer and DC motors performs automatic load share control between the DC motors.

Abstract: A method and an apparatus for controlling release of a hoisting motor brake in a hoisting apparatus, where electricity is used as the driving force and a squirrel cage motor as the hoisting motor for hoisting or lowering a load attached to a hoisting member of the hoisting apparatus. Controlling of brake release comprises measuring the current and supply voltage of the hoisting motor after the start-up period of the hoisting motor and determining a variable which describes the load of the hoisting apparatus from the current and supply voltage. The variable describing the load is compared with a pre-determined limit value and hoisting or lowering of the load is interrupted if the variable describing the hoisting apparatus load exceeds the limit value set for the hoisting movement when the load is hoisted or if it exceeds the limit value set for the lowering movement when the load is lowered.

Abstract: A method and an apparatus for a medium indexing device, such as an ink jet printer, that includes utilizing greater torque generated by a motor at lower speed and lower torque available by the motor at higher speeds. Motion profiling during acceleration and deceleration is designed to better utilize available torque provided by the motor in order to quickly position the medium during start-stop operations and to reduce the maximum power or speed required of the motor during the indexing operations. The motor may include a stepper or servo motor, and may apply to medium indexing devices other than printers. In addition, a velocity discontinuity in motor speed is provided near the stop position to prevent the medium from overshooting the intended stop position.

Abstract: A vehicle co-operative control system is provided which suppresses the torque steer phenomenon by co-operatively controlling a driving force and/or braking force distribution device and an electric power steering device without changing the control device of the electric power steering device for a vehicle having a specification in which the co-operative control is not carried out or with the introduction of only a minimal change. The control device can also be applied to a vehicle having a specification in which the co-operative control is carried out.

Abstract: A drive circuit including a motor for positioning a damper from a rest position to a stalled position and protect the drive mechanism from damage due to increased current to the drive motor when the damper stalls by including a current limiter to prevent the current in the motor from exceeding a predetermined value.