Abstract: A system and method are provided for estimating temperature of a rotor of a motor configured to calculate temperature of the rotor using an actual measured data-based thermal model (thermal impedance model) and an energy loss model, and to estimate temperature of the rotor using the calculated temperature variation of the rotor. The method includes calculating, by a controller, an energy loss of the motor using driving conditions of the motor. The controller is also configured to calculate a temperature variation of the rotor in a predetermined reference temperature using the calculated energy loss and thermal resistances of the rotor and a stator of the motor. Further, the controller is configured to estimate a rotor temperature in the predetermined reference temperature using the temperature variation of the rotor.

Abstract: A control device of a machine tool which filters possible continued machining time data estimated from a value of current of a motor to thereby enable an accurate grasp of the time regardless of fluctuation of the load, that is, a control device of a machine tool which has a motor which drives a spindle, which control device of a machine tool can use a value of current of the motor, an overheat temperature of the motor, and a temperature of the motor to estimate the time until reaching the overheat temperature when the current operating current continues to be run through the motor, filter the estimated value of time by a filter to display a possible continued processing time, change a filter time constant based on either of a value of current and current command value, and accurately display the possible continued processing time even if the load fluctuates.

Abstract: An assembly provides a dual function for mounting a port connector on a circuit board and also secures a capacitor to the circuit board. The assembly includes the circuit board and a monolithic plastic frame having a flange, a snap structure, a capacitor cradle, and a socket section. The flange has a fastening structure for fastening the frame to the circuit board. The snap structure for a snap-in attachment of the port connector to the frame is arranged near an end edge of the circuit board. The capacitor cradle for holding a cylindrical capacitor is formed adjacent to the snap structure and is elevated from the circuit board by an air gap. The socket section bears socket contacts for receiving capacitor contact leads.

Abstract: A controller includes a voltage determination module, a bus voltage command module, and a power factor correction (PFC) control module. The voltage determination module determines a desired direct current (DC) bus voltage for a DC bus electrically connected between a PFC module and an inverter power module that drives a motor. The voltage determination module determines the desired DC bus voltage based on at least one of torque of the motor and speed of the motor. The bus voltage command module determines a commanded bus voltage based on the desired DC bus voltage. The PFC control module controls the PFC module to create a voltage on the DC bus that is based on the commanded bus voltage.

Abstract: An electric power tool includes a drive source, a rechargeable battery that supplies power to the drive source, a voltage meter that measures voltage of the rechargeable battery, a temperature meter that measures temperature of the rechargeable battery, and a drive control unit that regulates the power supplied to the drive source from the rechargeable battery to drive the drive source. If the battery temperature measured by the temperature meter is lower than or equal to a predetermined temperature when the battery voltage measured by the voltage meter is lower than or equal to a predetermined voltage, the drive control unit drives the drive source differently from normal driving that is performed if the battery temperature is higher than the predetermined temperature when the battery voltage is higher than the predetermined voltage.

Abstract: An exemplary power supply system for a direct-current drive includes a power converter for at least one direction-dependent two-quadrant operating mode, at least one associated pulse-based actuation device, an input-side connection and an output-side connection for the power converter, and at least one mechanical interruption device for the input-side connection and/or the output-side connection. The power supply system is provided to continually provide values of a current flowing on the output-side during operation by receiving an STO (safe torque off) signal, immediate changeover of the power converter operating mode into the inverter limitation if an STO signal is received, interrupting a feed of actuation power through the actuation device into the power converter, and supplying an interruption signal to the at least one mechanical interruption device once a second subsequent time interval has elapsed and the current flowing on the output side has not decayed below a safety-critical limit value.

Abstract: A method for detecting a motor error of a motor driven power steering (MDPS) may include: calculating, by a control unit, a Q-axis command current of a motor through a Q-axis command current calculation unit, according to requested torque; calculating a command current of each phase of the motor from the calculated Q-axis command current of the motor; controlling the motor according to the Q-axis command current of the motor, and sensing a measured current of each phase of the motor through each current sensor; determining whether each phase of the motor is disconnected, through the command current and the measured current of each phase of the motor; and outputting the determination result to an output unit.

Abstract: A motor control device includes a measuring unit configured to output a measurement value corresponding to a rotation speed of a motor; and a control unit configured to control driving of the motor such that the measurement value makes closer to a target value. When the measurement value does not exceed a predetermined abnormality determination threshold, the control unit controls the driving of the motor based on a difference between the measurement value and the target value. The abnormality determination threshold is set in a positive direction or in a negative direction with reference to the target value. When the measurement value exceeds the abnormality determination threshold, the control unit controls the driving of the motor based on a difference between a corrected measurement value and the target value. The corrected measurement value is set in the same direction as the direction in which the abnormality determination threshold is set.

Abstract: A powered screwdriver system includes an electric ratchet. In accordance with one aspect, the powered screwdriver system includes a driver housing and includes a motor disposed within the housing. A working end provides a rotational output and is mechanically coupled to the rotor. A power source provides power to the motor. A controller receives signals representative of a motor condition and, based on the received signals, controls the motor in a manner providing the electric ratchet.

Abstract: The invention relates to a device for actuating actuators in a motor vehicle having an at least partially metallic housing (MG) in which an electric circuit is arranged, which has at least one high-voltage-generating circuit (HES) for generating an output voltage (UHS) which is higher than a voltage which is considered safe for people, from the on-board motor vehicle power system voltage. The electric circuit has a monitoring circuit (UES) which has a first input (E1) which is connected to a reference voltage (Vref), and has a second input (E2) which is connected to the at least partially metallic housing (MG), and the output (A) of which is operatively connected to the high-voltage-generating circuit (HSS) in such a way that in the case of a differential voltage at the two inputs (E1, E2) which is higher than a predefined value, the high-voltage-generating circuit (HSS) is deactivated or the output voltage (UHS) thereof is limited to a value of at maximum the voltage which is considered safe for people.

Abstract: A control unit for an electric machine. The control unit has a processing unit and a power output stage connected to the processing unit. The power output stage is connected to outputs of the control unit for stator coils of a stator of the electric machine. The processing unit is designed to supply current to the power output stage for generating a stator field, in particular a rotating magnetic field. The control unit comprises an electrical energy store, in particular an intermediate circuit capacitor or accumulator, connected to the power output stage. The control unit includes an input for a control signal, for example a temperature signal. The processing unit is preferably designed to actuate the power output stage as a function of the temperature signal such that the energy store can be heated by a current application pattern generated by the power output stage.

Abstract: A roll shade system is disclosed. The roll shade system includes a motor configured to remain stationary during operation of the motor, a support shaft supporting the motor wherein the support shaft is configured to remain stationary during operation of the motor, and a roll shade tube configured to be rotatable about the motor and the support shaft during operation of the motor. The roll shade system further includes stationary components including a wiring connector, an input wiring system, a bearing, an antenna, a coaxial cable, a motor controller, a counterbalance spring. The roll shade system also includes rotatable components including a bearing housing and one or more O-rings.

Abstract: An inverting apparatus and a photovoltaic power system using the same are provided. The inverting apparatus includes an inverting circuit, a control circuit, and a voltage regulator-based ground detection circuit. The control circuit controls the power conversion of the inverting circuit. The voltage regulator-based ground detection circuit samples an input voltage of the DC input power, and performs voltage regulation and voltage division on the input voltage to generate a ground indication voltage. The electric potential of the output terminal of the voltage regulator is built based on a photovoltaic ground terminal of a photovoltaic module. The ground indication voltage is the voltage difference between an output terminal of the voltage regulator and a device ground terminal of the inverting apparatus. The control circuit determines whether a ground fault occurs to the photovoltaic module and enables a ground protection mechanism to control the inverting circuit when the ground fault occurs.

Abstract: A motor control device includes an H-bridge circuit for controlling on/off of a current fed to a motor, a drive circuit for driving the H-bridge circuit, a drive command signal generator for generating a drive command signal including a pulse signal having a predetermined drive frequency for sending a command to drive the motor, a current detection circuit that includes a current detection resistor and a comparator connected in series with the motor and outputs a comparison output signal based on comparison between a current detection signal of a motor current and a target value signal, a latch circuit for holding a current detection result based on an ON signal of the drive command signal and the comparison output signal, and a gate circuit for driving the drive circuit based on the ON signal of the drive command signal and a latch output signal from the latch circuit.

Abstract: The invention relates to a method for operating a power output stage (2), in particular an electrical machine, which comprises a bridge circuit (3) with at least one half-bridge (1), wherein the half-bridge (1) has two power semiconductor switches (4, 5) which are connected in series and which are each supplied with an operating control voltage during normal operation in order to set a power voltage, and wherein the power voltage (u4, u5) of the respective power semiconductor switch (4, 5) is detected for the purpose of short-circuit monitoring. In this case, provision is made, in order to check the functioning of the short-circuit monitoring means in a check mode for the power semiconductor switches (4, 5), for a test control voltage which is below the operating control voltage to be set at least temporarily at the same time.

Abstract: An inverter device for an electric vehicle includes an inverter circuit that controls an electric motor connected to a wheel via a connecting member and a control unit that controls torque of the electric motor. The control unit includes a current control unit that executes control so that a q-axis current command for the electric motor matches a current flowing through the electric motor, and a limiter unit that puts limitations so that a magnitude of the q-axis current command does not become equal to or smaller than a preset predetermined value.

Abstract: Disclosed is a power supply control apparatus of an electric load that includes an upstream side switching element and a downstream side switching element and detects various abnormality states of a load wiring by a small number of detection signals. The power supply control apparatus includes a control circuit unit that gives a power supply command signal to the upstream switching element connected in series with the electric load and gives a conduction command signal to the downstream switching element, open-circuits the upstream and downstream switching elements by a synthetic overcurrent determination storage circuit that is operated in response to an overcurrent detecting circuit, monitors a value of one variable divided voltage generated by the voltage monitoring circuit for the electric load, and identifies and stores a wiring abnormality such as a negative line supply fault, a positive line ground fault, and a load short circuit abnormality.

Abstract: Disclosed are a high-voltage protection circuit, a high-voltage protection method and a power supply. The high voltage protection circuit comprises a main relay, an auxiliary relay, a first resistor, a second resistor, a first capacitor and a second capacitor, wherein one end of the main relay is connected to the input port of a live line, and the other end thereof is connected to the output port of the live line; one end of the auxiliary relay is connected to the input port of the live line, and the other end thereof is connected between the first resistor and the second resistor; one end of the first capacitor is connected to the output port of the live line, and the other end thereof is connected to a neutral line parallel to the live line; the second capacitor is connected to both ends of the main relay in parallel; and the second resistor and the first resistor are connected between the input port and the output port of the live line in series in sequence.

Abstract: The invention provides a method and a device capable of precisely and simply extracting data used for abnormality determination and life diagnosis of a drive system of an industrial robot while executing a normal action program. Regarding a torque signal Tf outputted from a motor driver for controlling a motor in accordance with a position command Xs generated based on an operation program of a robot to the motor, a highpass filter is applied after gravity compensating torque and interference torque due to other shafts of the robot are removed from the torque signal Tf, and an abnormality in a reducer is determined based on an extracted oscillating component of the reducer.

Abstract: An output control device configured to control the output of a running drive source mounted on a vehicle includes an anomaly discriminator which judges that the output control device is anomalous, if excess acceleration G (output difference index) of the vehicle remains greater than or equal to a predetermined threshold value G1, . . . , G7 for a predetermined time t1, . . . , t7 or longer, wherein the predetermined time t1, . . . , t7 for the anomaly discrimination is set so as to shorten with increase in the threshold value G1, . . . , G7 of the excess acceleration of the vehicle.

Abstract: The present invention relates to a vehicle power controlling apparatus, and more particularly, to a vehicle power controlling apparatus for interrupting a dark current from an ECU power front stage of a motor driven power steering (MDPS) system.

Abstract: A method of controlling a current flowing through a component of a drive comprising the steps of: estimating the current flowing through a component; estimating the temperature of the component; comparing the estimated temperature with a desired maximum temperature for the component; and adjusting the current flowing through the component based on the result of the comparing step.

Abstract: A system and method for monitoring and controlling the amount of electrical current provided to a motor used to actuate a field device within a control system.

Abstract: Provided is an image forming apparatus capable of detecting the ON/OFF state of each of two interlock switches connected in series to a power line, and detecting the opening/closure of each of two covers. The first and second interlock switches are set on/off according to the opening/closure of the first and second covers respectively. The first interlock switch is connected to a supply voltage when the first interlock switch is on, and is connected to a detection voltage being lower and on which the load does not operate when the first interlock switch is off. A control part detects the opening/closure of the first cover and the second cover based on a voltage on the power line between the first interlock switch and the second interlock switch and a voltage on the power line between the second interlock switch and the load.

Abstract: A motor control device includes: a frequency instruction setting section for outputting a plurality of frequency instructions; an AC voltage instruction generation section for generating and outputting an AC voltage instruction based on each of the frequency instructions; a voltage application section for applying voltage to a motor based on the AC voltage instruction; a current detection section for detecting motor current flowing in the motor; and a type determination section for determining the type of the motor based on a transfer characteristic of the motor calculated from the motor current, the AC voltage instruction, and the frequency instruction.

Abstract: A power tool including a motor for rotatably driving a tool bit at an attained rotational speed, a source for supplying an electric current to the motor, a sensor for measuring the current, and a control device. The control component fulfills the task of detecting a variation of the slope of the current in the course of time, and generates a control signal. The rotational speed of the tool is reduced in response to the control signal. The power tool automatically detects whether the work piece operated by the tool bit reaches a predetermined position by electronic control means. It may make sure that the screw is driven into a piece of wood and does not go beyond the predetermined position once it detects that the work piece reaches the position and carries out a changing action.

Abstract: In a method for predefining a generator-based braking power of an electric machine in a vehicle, a motor-based propulsion power is predefined as a function of the position of a first final control element, e.g., an accelerator pedal, and the generator-based braking power is predefined as a function of the position of the first final control element, the generator-based braking power assuming values which are unequal to zero, already at an actuated position of the first final control element.

Abstract: A power supply (20) for providing a desired current to an electric load (23) broadly comprises: a current limiter (21) for providing a desired current; a current sensor (28) for determining the actual current supplied by the current limiter and providing a feedback signal (30, 31) to the current limiter for causing the current limiter to reduce the error between the desired and the actual currents; and a test circuit (24) for temporarily changing the actual current sensed by the current sensor to a level different from the desired current for causing the current limiter to adjust the magnitude of the current provided thereby; whereby the operation of the power supply may be tested. The invention also provides an improved method of operating such a power supply.

Abstract: A diagnostic system and method for an electric power steering system are provided. The diagnostic system includes a first microprocessor that determines a first relative position value indicating the relative rotational position of the rotatable shaft at the first time based on the signals from first and second position sensors. A second microprocessor determines a second relative position value indicating the relative rotational position of the rotatable shaft at the first time based on the signals from third and fourth position sensors. The first microprocessor determines whether the first relative position value is an acceptable value based on a difference between the first relative position value and the second relative position value.

Abstract: A rotating electrical machine control apparatus includes a plurality of rotating electrical machine controllers and a target voltage setting device. Each of the rotating electrical machine controllers includes a rotating electrical machine and a power supply controller configured to perform power supply control on the rotating electrical machine. The rotating electrical machine controllers have different imposed loads. The target voltage setting device is configured to set DC-side voltages of the rotating electrical machine controllers to a target voltage defined as a thermal equilibrium voltage which represents the DC-side voltages obtained when the rotating electrical machine controllers are in a thermal equilibrium condition.

Abstract: A method for fault recognition in an electric machine controlled by an inverter in a motor vehicle, in which the phase currents of the electric machine are ascertained, in particular ascertained by measuring, and a fault is recognized if at least one of the phase currents or a variable derived therefrom, exceeds a predefined upper threshold value, the upper threshold value being established as a function of operating parameters of the motor vehicle, in particular of the electric machine and/or of the inverter.

Abstract: A retarding control system for a machine is disclosed. The retarding control system may include a locator, configured to sense a location of the machine. Additionally, the retarding control system may include a sensing system configured to sense at least one a parameter indicative of a retarding of the machine. The retarding control system may also include a retarding system configured to retard the machine and a braking system configured for braking the machine. The retarding control system may also have a map configured to store at least one known retarding condition and at least one known retarding location. Further, the retarding control system may include a controller. The controller can be in communication with the locator, the sensing system, the retarding system, the braking system and the map. The controller may be configured to update the map based on the location, and the retarding condition.

Abstract: The present invention concerns a control system for an electric motor, wherein an operating mode with predetermined value assignments is selected for a parameter set for controlling an electric motor and the pulse frequency of a control signal for the electric motor is set in accordance with the selected operating mode in order thereby to signal to the electric motor the selected value assignments for the parameter set.

Abstract: A motor controlling apparatus includes a first target torque value calculator, a frequency detector, a second target torque value calculator, a torque command value calculator, a torque limiter, and a controller. The first target torque value calculator calculates a first target torque value, which is a target value of an output torque of a motor. The frequency detector detects a motor rotational frequency. The second target torque value calculator calculates a second target torque value based on the rotational frequency. The torque command value calculator mathematically combines (e.g., adds) the first and target torque values to calculate a torque command value. The torque limiter sets the signs of the first target torque value and the torque command value to be equal to limit the torque command value according to the first target torque value. The controller controls the motor based on the limited torque command value.

Abstract: A circuit arrangement for an electrical machine having a plurality of stator windings, with each stator winding including at least a first winding phase and a second winding phase. The circuit arrangement includes at least a prespecified first and a prespecified second selection of in each case a plurality of half-bridges. A common connection of the two switching elements of the respective half-bridge of the first selection can be electrically coupled in each case to a connection of the first winding phase of the respectively associated stator winding. A common connection of the two switching elements of the respective half-bridge of the second selection can be electrically coupled in each case to a connection of the second winding phase of the respective associated stator winding.

Abstract: A converter module for a variable speed drive having a semiconductor device for precharge is described. The precharge circuit includes switching modules, one switching module with a first semiconductor switch connected in parallel or series with a second semiconductor switch. The second semiconductor switch is switched on and off during the precharge operation in order to limit the inrush current into the DC Link. After the precharge operation, the second semiconductor switch is turned on all the time and acts like a diode. The second semiconductor device may have a lower maximum current rating than the main semi-conductor devices. The lower current rated semiconductor device experience the same short circuit current as the higher current rated semiconductor device. The lower current rated semiconductor device can be supplied with a larger gate to emitter voltage than the higher current rated semiconductor device to equalize current between semiconductor devices.

Abstract: A system for determining if a tire of a vehicle is improperly inflated. The system includes a radar, a wheel speed sensor, and a controller. The radar is configured to emit a signal to detect a reflection of the signal off of an object positioned perpendicular to the vehicle, and to output an indication of a speed of the vehicle. The wheel speed sensor is configured to sense a speed of a wheel of the vehicle. The controller is configured to receive the indication of the speed of the vehicle from the radar, to calculate a speed of the vehicle based on the sensed speed of the wheel, and to determine a tire of the wheel is improperly inflated when the speed of the vehicle calculated using the wheel speed sensor varies by more than a predetermined amount from the speed of the vehicle determined using the radar signal.

Abstract: A PI calculation unit of a rectangular-wave voltage control unit calculates a control deviation by performing a PI calculation on a torque deviation relative to a torque command value, and outputs a voltage phase of a rectangular-wave voltage in accordance with the control deviation. A rate-of-change limiter imposes a restriction on the rate of change of the voltage phase. Here, the rate-of-change limiter lessens the restriction on the rate of change of the voltage phase, when the rate of change of the rotational speed of an electric motor is larger than a predetermined value representing an abrupt change of the rotational speed of the electric motor.

Abstract: A control device for a rotating electrical machine, which is able to reduce a tracking delay of an actual output torque and actual currents with respect to a fluctuating torque command and fluctuating current commands and to reduce steady state deviations, is obtained. The control device includes a torque current computing unit; an actual current computing unit; a current feedback control unit; and a voltage control unit that controls voltages on the basis of the two-phase voltage commands. The torque command includes a fluctuation cancellation torque command for cancelling transmission torque fluctuations transmitted from the internal combustion engine, and the current feedback control unit includes a harmonic controller that calculates the two-phase voltage commands by using a characteristic of a transfer function corresponding to a periodic function of a frequency of the transmission torque fluctuations.

Abstract: A handheld machine tool has a drive motor and a supplementary handle which is mounted on the housing of the handheld machine tool and is assigned a drive-torque limitation device, the drive-torque limitation device limiting the drive torque to a torque level below a maximum torque if the supplementary handle is not mounted on the housing.

Abstract: A method for controlling the operation of an arrangement of at least two electric machines coupled to different wheels of a motor vehicle and connected to a battery which provides an actual minimum and maximum limiting current for the electric machines. Desired torques are provided for the electric machines by a drive control logic. A desired current resulting from the desired torque is ascertained for each electric machine, and the sum of the desired currents are compared with the maximum and minimum limiting current. If the sum lies outside an interval defined by the limiting currents, the desired currents are adjusted using at least one change rule such that the sum of the desired currents lies within the interval. Adjusted desired torques are determined from the adjusted desired currents and used to control the electric machines.

Abstract: A system comprising an actuator and a controller configured to drive the actuator with a pulse width modulated (PWM) signal. The controller is configured to limit a duty cycle of the PWM signal in response to a current supplied by the PWM signal.

Abstract: There is provided a power controller including a drive circuit connected to a DC power supply to apply a first voltage to the drive circuit and configured to supply power to an external load, a current detection circuit configured to detect a current flowing in the drive circuit by converting the current into a second voltage corresponding to the current, and a current-voltage control unit configured to generate a reference voltage corresponding to a limit value of the current flowing in the drive circuit when the first voltage is applied to the drive circuit, and configured to control the drive circuit to operate in a desired current according to the first voltage, based on a comparison result of the reference voltage and the second voltage.

Abstract: A protective method is provided against torque peaks between a motor adapted for setting a shaft of the motor into rotation and an electric source adapted for electrically powering an electric assembly and including a fixed section and a rotating adapted for rotating with the shaft. The method includes a step for controlling the operation of the electric source forcing the rotary movement of the rotating section with the shaft to observe an instruction relating to the torque of the rotating section applied to the shaft of the motor, the instruction being adapted depending on at least one element characterizing a current operating state of the motor.

Abstract: A control method comprises determining wheel creep of a wheel operably coupled to a traction motor and limiting a rate of change of an excitation frequency applied to the traction motor to drive the wheel, based on the determined wheel creep. According to one aspect, the rate of change of the excitation frequency is limited if the wheel creep exceeds a wheel creep threshold.

Abstract: When an abnormality occurs in a refrigeration cycle, the inverter motor provided in the air conditioner is stopped reliably and contacts of the main relay are prevented from degradation and fusion. A power circuit 1 of the air conditioner includes a rectifier circuit RC, a capacitor C (smoothing unit), a main relay 10 provided on a current path between the rectifier circuit RC and the capacitor C, an inverter circuit 30, a microcomputer 100, and a delay circuit 40. The microcomputer 100 has an inverter circuit control unit 110, a main relay opening/closing control unit 120, a waveform forced cut-off unit 130, and a cut-off signal output unit 140.

Abstract: The present invention relates to a high power battery system having a battery system monitoring electronics and battery modules being electrically connected in series via an operating current line. At least one battery module is a bypass battery module comprising a bypass switch and a bypass line for electrically bypassing the battery module. For each bypass battery module a module monitoring unit of the monitoring electronics monitors the assigned battery module and detects a fault state. In the fault state, the battery system monitoring electronics measures the current flow in the operating current line connecting the battery modules and switches the bypass switch of the bypass battery module concerned from a normal operating position to a bypass position at a time when the current flow in the operating current line is lower than a predetermined limit value.

Abstract: Dynamic reconfiguration-switching of motor windings in an electric motor in an electric vehicle is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting the electric motor in the electric vehicle is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.

Abstract: An exemplary power supply assembly includes a drive device having a bus capacitor. A switch associated with an input side of the drive device selectively connects the drive device to a power supply. An inductor has an impedance that limits an amount of current supplied to the bus capacitor during an initial charging of the bus capacitor when the switch connects the input side of the drive device to the power supply. A restrictive circuit portion dampens a resonance effect of the inductor. The restrictive circuit portion has a resistance that allows the bus capacitor to charge quickly. The impedance of the inductor has a more significant effect on how quickly the bus capacitor charges than an effect of the resistance. A dampening factor of the restrictive circuit controls a voltage of the bus capacitor during the charging of the bus capacitor.

Abstract: A motor driven power steering (MDPS) may include: a vehicle speed sensor configured to sense vehicle speed; a temperature sensor configured to sense a temperature of a power pack; a current sensor configured to sense an amount of current applied to the MDPS; a storage unit configured to store a thermal resistance value based on the vehicle speed with respect to the temperature of the power pack; and a control unit configured to calculate an estimated temperature by reflecting the thermal resistance value based on the vehicle speed with respect to the temperature of the power pack and the current amount applied to the MDPS into a temperature estimation function, and drive a motor according to the calculated estimated temperature.