Abstract: A marine propulsion control system for use with a marine vessel, includes a port side engine in electronic communication with a port side engine controller and a starboard side engine in electronic communication with a starboard side engine controller. A control station includes a port lever configured to control a throttle of the port side engine, a starboard lever configured to control a throttle of the starboard side engine, and a user interface. A propulsion control processor is in electronic communication with the port side engine controller, the starboard side engine controller, and control station. In a synchronized operating mode, the propulsion control processor transmits a throttle instruction to the port side engine controller and the starboard side engine controller pursuant to a throttle position of a master lever corresponding to the first of the port lever and starboard lever to be actuated upon activation of the synchronized operating mode.

Abstract: Technical solutions for controlling operation of an electric machine by a control system are provided. The control system comprises an inverter and a controller performing a first operation to produce a first output data representing a motor control current command in a first time period beginning at one of a plurality of initial times occurring at a first periodic timing interval. The controller also performs a second operation upon the first output data to produce a second output data in a second time period. The controller also performs a third operation at a periodic command time to produce a motor control voltage command using the second output data in response to satisfaction of a timing criterion. The timing criterion is based upon comparing the command time and occurrence of a posting time after the initial time. A method of enforcing timing restriction to synchronize non-deterministic motor control events is also provided.

Abstract: A motor driving apparatus and a method of driving a plurality of permanent magnet synchronous motor (PMSM) using a single inverter is described. The motor driving apparatus includes a single power conversion apparatus configured to supply power to a plurality of motors and a control apparatus configured to control the power conversion apparatus to adjust a phase current ratio supplied to the plurality of motors from the single power conversion apparatus according to a requirement of each of the plurality of motors.

Abstract: In the first synchronous system of the synchronous control unit (1), movement commands of the first motor (23) and the second motor (13) made by the movement command making section (9), which are synchronized with each other, are respectively supplied to the first amplifier (22) and the second amplifier (12) through the first communication path (11) and the second communication path (21). In the second synchronous system switched from the first synchronous system, the first motor (23) is decelerated by a deceleration command made by the deceleration making section (29) and the second motor (13) is decelerated synchronously with the first motor by a movement command made by the position feedback value controlled by the first motor (23) supplied to the second amplifier (12) through the third communication path (31).

Abstract: In order to provide an X-ray imaging apparatus including a two-phase anode rotation mechanism driving circuit having a small and light configuration, one end of the main stator coil is connected to a three-phase full-bridge inverter circuit and the midpoint between two semiconductor switches of the first arm, one end of the auxiliary stator coil is connected to the midpoint between two semiconductor switches of the second arm, and the other ends of the main stator coil and the auxiliary stator coil are connected to the midpoint between two semiconductor switches of the third arm. The semiconductor switches are switched using an inverting circuit and a delay circuit so that a first AC voltage is supplied to the one end of the main stator coil and a second AC voltage, which is shifted in phase by 90° from the first AC voltage, is supplied to the one end of the auxiliary stator coil.

Abstract: Disclosed embodiments include a method for locking and synchronizing Hall-sensor driven motors electronically. A programmable integrated circuit microcontroller is positioned between the Hall-sensors and the motor drivers. The microcontroller is programmed to receive signals from the Hall sensor, mitigate the errors introduced due to uneven magnetization and sensor misalignments, and then synchronize/lock the angle and speed of the motors such that the motors operate as if on a common shaft.

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: System and methods for protecting motors of a vehicle are provided. A system includes a current transformer device for each phase of the three-phase power received by each protected motor. Each current transformer device includes a switch that is normally in a first position and is configured to monitor an output current of fuse through which the power is transmitted, compare the output current to a threshold current level, and, when the output current is below the threshold current level, change the switch to a second position. The system also includes a processing circuit configured to control operation of the one or more motors of the vehicle. The processing circuit is configured to determine whether one or more of the switches of the plurality of current transformer devices is in the second position and, if so, activate a fault condition.

Abstract: A synchronous-machine starting device includes an electric power conversion unit for converting supplied electric power into AC power for supply to the armature of the synchronous machine, a rotor position detection unit for detecting a position of the rotor of the synchronous machine based on an AC voltage in the armature of the synchronous machine detected by an AC voltage detection unit, an electric power conversion control unit for controlling the electric power conversion unit based on the position of the rotor detected by the rotor position detection unit, and an abnormality detection unit detecting a rotation abnormality of the synchronous machine based on the AC voltage detected by the AC voltage detection unit after supply of the field current to the rotor of the synchronous machine is started.

Abstract: Each screen (1) of a group of screens is configured by a method in which a function is approximated, the function giving the instantaneous axial position (H(t)) of the load bar (2) thereof along an axis (Z) of translation in the form of a function having, as a variable, the instantaneous angular position (y(t)) of a winding device (4). The load bars of the screens are sequentially moved into a plurality of positions in which the load bars are aligned, and then the angular position (y(t)) of the winding device is determined. Next, the coefficients defining the approximation function of each screen are determined. The movement of the load bar of each screen is controlled by an instantaneous angular-position set value (?(t)), which is in turn predetermined from a representative profile using the one-to-one approximation function.

Abstract: A motor controller includes: a converter for converting an alternating current to a direct current; a first inverter for converting the direct current in a direct-current link of the converter to an alternating current for driving a first motor; a second inverter for converting the direct current in the direct-current link to an alternating current for driving a second motor; a power-failure detection unit for detecting a power failure on the side with the alternating-current power supply; and a command creation unit for creating a drive command for each of the first inverter and the second inverter when no power failure has occurred, while creating a drive command for the first inverter and also creating a drive command for the second inverter by using position feedback information of the first motor driven according to the drive command for the first inverter, when a power failure has occurred.

Abstract: A condition monitoring method for an electrical machine is provided. The method includes providing at least one first sensor element embedded in or disposed on at least one substrate element located in a stator core for obtaining a first set of data. The method also includes providing at least one second sensor element for obtaining a second set of data from the electrical machine. Further, the method includes generating signals indicative of changes in characteristics of the first sensor element based on the second set of data. Finally, the method includes refining the first set of data by combining the first set of data with the generated signals.

Abstract: A small-sized load drive system which, even with three three-phase inverters, significantly reduces noise regardless of control duty ratio. The load drive system includes three-phase inverters, and first, second, and third control units. The inverters are connected to loads, respectively. The first control unit generates sawtooth wave voltage and controls the inverter according to the sawtooth wave voltage. The second control unit generates inverse sawtooth wave voltage and controls the inverter according to the inverse sawtooth wave voltage. The third control unit generates triangular wave voltage which has ramps respectively equal to the sawtooth/inverse sawtooth wave voltage and either has a same phase or is out of phase by half a period relative to the sawtooth/inverse sawtooth wave voltage, and also controls the inverter according to the triangular wave voltage.

Abstract: A rail vehicle has a powered bogie, wherein the powered bogie has driven wheels. Each driven wheel of the powered bogie can be driven by an electric machine, with a power converter being assigned to the electric machine. As a result, a separate power converter is assigned to each driven wheel.

Abstract: Presently disclosed is a method and system for processing standard part description programs in real time into the tool position control data appropriate to a CNC machine's standard and high bandwidth mechanisms, respectively. The result is precise tool tip control that tracks the programmed path at all times while maintaining the appropriate feed rates and accelerations for each type of mechanism. In one exemplary embodiment, a hybrid mechanism employing a high bandwidth mechanism mounted on and moved by a standard mechanism is employed. The command vector for the high-bandwidth mechanism is computed by subtracting the tool tip vector filtered to comprise only the tool tip positions and trajectories realizable by the standard mechanism from an ideal tool tip trajectory vector that represents the complete programmed path. These calculations produce a synchronous set of movements for both standard and high bandwidth mechanisms.

Abstract: The present invention is directed to methods for forming an inverter circuit for operating a drive motor of an electric vehicle, which can more effectively reduce the switching noise generated by a power module during the operation of an inverter.

Abstract: An automatic control mechanism for a group of motorized screens in which each screen includes a load bar that is displaced according to a predefined travel and wherein the control mechanism determines a shift parameter between a first reference position of each screen and a second reference position, one of these two reference positions being a reference position common to the screens of the group. The control mechanism takes into account at least one shift parameter to obtain, following a control command, at least the alignment of the load bars that have been displaced.

Abstract: A method is provided for detecting an insufficient or missing phase current in a permanent magnet synchronous motor, and includes determining a composite vector position of a combined three-phase phase current with respect to a stationary portion of the motor, and assigning a sector to the position. The method includes comparing the phase current to a calibrated threshold current corresponding to the sector, and executing a response when the absolute value is less than the threshold. A vehicle includes an energy storage device (ESD), a motor/generator configured as a permanent magnet synchronous motor, a voltage inverter, and a bus for conducting DC current from the ESD to the inverter. A controller detects an insufficient phase current, determines a current vector position of the three-phase AC, assigns a sector to the position, and executes a response when an absolute value of the phase current is less than a calibrated threshold.

Abstract: Provided is a small-sized load drive system which, even with three three-phase inverters, significantly reduces noise regardless of control duty ratio. The load drive system includes three-phase inverters 301 to 303, and first, second, and third control units 401 to 403. The inverters 301 to 303 are connected to loads 211 to 213, respectively. The first control unit 401 generates sawtooth wave voltage and controls the inverter 301 according to the sawtooth wave voltage. The second control unit 402 generates inverse sawtooth wave voltage and controls the inverter 302 according to the inverse sawtooth wave voltage. The third control unit 403 generates triangular wave voltage which has ramps respectively equal to the sawtooth/inverse sawtooth wave voltage and either has a same phase or is out of phase by half a period relative to the sawtooth/inverse sawtooth wave voltage, and also controls the inverter 303 according to the triangular wave voltage.

Abstract: A wiper apparatus includes: a wiper blade driven by a motor; and a wiper blade driven by a motor. The motors are drive-controlled by control microcomputers, respectively. The control microcomputers are connected to each other through a communication line. While exchanging position information of the wiper blades through the communication line, the control microcomputers synchronously drive the motors on the basis of a position relationship between both of the wiper blades. In the case where a communication abnormality occurs when the position relationship between the wiper blades is in a normal state, the wiper blade is stopped after reaching a lower turning position. In the case where the communication abnormality occurs in a state where the position relationship between the blades is inverted, the blade is stopped after reaching an upper turning position.

Abstract: A method for controlling a mechanically commutated electric motor, wherein the rotational angle of the output of said motor is determined by means of detection of the change in back electromotive force, when the electric motor commutates, and wherein the power supply to the electric motor is halted after a predetermined number of detected commutations.

Abstract: A field-oriented control method for an electric drive comprising a plurality of electric motors, for implementing a tension mechanism, especially for load cable and/or gearing means, using measurements of a polyphase motor actual current. The measured values are transformed into a direct current component and a quadrature current component, based upon a magnetic rotor field or flux angle, in a rotor flux-based d,q coordinate system. The quadrature and direct current components from the actual current are subjected to a comparison with predetermined quadrature and direct current components of a current command value.

Abstract: A synchronous controller capable of gently changing a synchronous multiplying factor and setting the gentleness of changing of the synchronous multiplying factor without shocking a machine. A block for gently changing the synchronous multiplying factor is added between blocks before and after the changing of the synchronous multiplying factor. Synchronous multiplying factors a and b before and after changing of the synchronous multiplying factor designated in the added block, a motion amount p of master axis, a motion amount of a slave axis, and a residual motion amount v of the master axis after the completion of changing the synchronous multiplying factor (or a preliminary motion amount u of the master axis from the start of motion of the block concerned to a position for the start of changing of the synchronous multiplying factor) are read out. A gradient of changing the synchronous multiplying factor and the preliminary motion amount u (or the residual motion amount v) are obtained based on these data.

Abstract: An inverter having M×N arms is connected to a first motor having N groups of M phase coils and a second motor having M groups of N phase coils. At least one of the first motor and the second motor has as many teeth as the number of phases of the motor multiplied by an integer, and the M×N coils of the motor are wound around the teeth by equal to or more than two coils for each of the teeth. Drive points of the M×N coils of the first motor are connected to output points of the corresponding arms of the inverter. Drive points of the N×M coils of the second motor are connected to output points of the arms of the inverter, so that each of the N phase windings in each of the M groups of the second motor is connected to each of the N drive points of the first motor, the N drive points having the same phase.

Abstract: A motor control device includes a velocity detection unit, a motor control unit, a phase difference detection unit, and a correction value calculation unit. The velocity detection unit detects each velocity of a plurality of driven bodies or of a plurality of motors which independently drives a corresponding one of the driven bodies. The motor control unit independently controls each of the motors based on the velocity and a predetermined velocity directive value. The phase difference detection unit detects a phase difference among each of the driven bodies. The correction value calculation unit calculates a correction value for the velocity or the velocity directive value based on the phase difference.

Abstract: The invention includes a system and method for generating simulated encoder outputs in a control system. An output pulse width between reference position inputs is computed, the output pulse width being based upon a difference between an updated reference position input and a previous reference position input, and upon a time interval between the reference position inputs. Next, a plurality of simulated encoder pulses is output between updates of the reference position input based upon the computed output pulse width. The output pulse is thereafter adjusted in a closed loop manner between updates of the reference position input.

Abstract: The present invention relates to a method and relevant electronic device (10) for determining the hydraulic flow rate in a pump driven by a synchronous electric motor (12), said motor (12) being of the type comprising a rotor (14), equipped with a permanent magnet, which is rotation-driven by the electromagnetic field generated by a stator (16) equipped with pole pieces (18) with relevant windings. The method comprises an indirect measuring of the flow rate through the following steps of: acquiring at least one pump operation variable; comparing the value of said variable with a predetermined correlation table to hydraulic flow rate values and determining a corresponding flow rate value.

Abstract: An apparatus for use with an encoder feedback device includes a comparator, a counter, and a prediction unit. The encoder feedback device is coupled to rotate with a rotating load and operable to generate at least one feedback position signal indicative of movement of the rotating load. The comparator is operable to receive the feedback position signal and generate a first position signal including a plurality of edges based on the feedback position signal. The counter is operable to receive the first position signal and count the edges to periodically generate position values at a predetermined update interval. The prediction unit is operable to receive a position data request at a first time and predict a position of the rotating load at the first time as a function of at least a subset of the position values generated prior to the first time and a misalignment between the first time and the predetermined update interval to generate an aligned position signal.

Abstract: A method for controlling a mechanically commutated electric motor, wherein the rotational angle of the output of said motor is determined by means of detection of the change in back electromotive force, when the electric motor commutates, and wherein the power supply to the electric motor is halted after a predetermined number of detected commutations.

Abstract: A transmission path delay is set in a shift setting register. A slave unit generates a PRE_ITP signal in response to a timing signal (ITP signal) issued by a master unit. The phase difference between this PRE_ITP signal and the ITP signal unique to the slave unit is loaded into a period modification counter. A timer corrects a reference value, outputs position/speed control period signals (SYN signals) and counts down the period modification counter with these SYN signals until the period modification counter reaches zero. Furthermore, the ITP signal unique to the slave unit is outputted every time a predetermined number of the SYN signals are outputted.

Abstract: A load driving device controls two motors by PWM signals. When a standard duty ratio of the PWM signals is 50% and a level of a drive instruction is the standard duty ratio, the standard duty ratio are output to the respective motors to provide a reverse phase relationship that the PWM signal of the standard duty ratio does not overlap. A continuous off-period and the standard PWM signal output when the level of the drive instruction is lower than the standard, and the continuous on-period and the standard PWM signal output when the level of the drive instruction is higher than the standard are changed over at the ratios corresponding to the level of the drive instruction.

Abstract: A method and assembly for synchronizing machine operations, the assembly comprising a reference generator for generating a speed reference signal and a position reference signal, a plurality of slave units, each slave unit including, a mechanical device, a separate motor linked to and driving the mechanical device and a separate unit controller for controlling the unit motor, the unit controller receiving and using the reference signals to control motor operation and a synchronizer receiving the reference signals from the control signal source and simultaneously providing the reference signals to each of the slave unit controllers for use in controlling operation of the motors in a synchronized fashion.

Abstract: A motor control apparatus includes a first FG pattern for generating a first induced voltage attendant upon rotation of the rotor of a motor; a second FG pattern for generating a second induced voltage due to noise; a differential amplifier for differentially amplifying the first and second induced voltages, which are input thereto; and a motor speed control unit for controlling rotation of the motor so as to achieve synchronization between the output of the differential amplifier and a prescribed frequency signal.

Abstract: The present invention provides a method for controllably moving a plurality of antennae in a wireless communications system. The method comprises activating a first and second actuator associated with a first and second one of the plurality of antennae to move the first and second antennae to a desired position. The power delivered to the first and second actuators is measured, and at least one parameter of at least one of the first and second actuators is reduced in response to the measured power being greater than a setpoint.

Abstract: An inverter having M×N arms is connected to a first motor having N groups of M phase coils and a second motor having M groups of N phase coils. At least one of the first motor and the second motor has as many teeth as the number of phases of the motor multiplied by an integer, and the M×N coils of the motor are wound around the teeth by equal to or more than two coils for each of the teeth. Drive points of the M×N coils of the first motor are connected to output points of the corresponding arms of the inverter. Drive points of the N×M coils of the second motor are connected to output points of the arms of the inverter, so that each of the N phase windings in each of the M groups of the second motor is connected to each of the N drive points of the first motor, the N drive points having the same phase.

Abstract: In a method for synchronizing drive units, a target value of the speed of each drive unit of a plurality of drive units speed is computed by determining the product of a maximum speed of the drive unit, a unit-dependent normalized ratio value of the drive unit, and a synchronization factor which is identical for all drive units. The ratio value defines the relative speeds of the individual drive units. Changing the synchronization factor causes synchronous speed changes of the drive units. As a result, a lasting synchronization can be realized across the entire speed spectrum.

Abstract: An elevator control device for controllably driving multiple traction units includes position sensors and current supplies. Each of the current supplies includes a position controller for generating a speed command for the corresponding traction unit based on input difference between a common position command for the traction units and a feedback signal derived from an output of the pertinent position sensor, a speed controller for generating a current command for the corresponding traction unit based on an input difference between the speed command generated by the position controller and a feedback signal obtained by differentiating the output of the pertinent position sensor, and a current controller for supplying an electric current to the corresponding traction unit based on the current command generated by the speed controller.

Abstract: A method of controlling synchronous running of a plurality of electronically commutated motors (22, 24, 26), each of which includes a stator having a stator winding (40, 42, 44), a permanent-magnet rotor (28, 30, 32), and at least one arrangement (34, 36, 38), associated with the respective motor, for sensing its rotor position and for generating a rotor position signal (H1, H2, H3). Also provided is an energization arrangement (46), to which the stator windings (40, 42, 44) of the motors are connected. The method includes the steps of detecting occurrence of a predetermined state of the rotor position signals (H1, H2, H3) and, in response thereto, triggering simultaneously commutation of the currents in all the motors.

Abstract: Performing communications between numerical control apparatus 1a and peripheral devices (composed of at least one of a servo amplifier 2a, a spindle amplifier 3a and a remote I/O unit 4a) by connecting a numerical control apparatus 1a and peripheral devices using a communication cable composed of a pair of data transmission cables 7 for transmission and a pair of data transmission cables 8, in a numerical control system having numerical control apparatus 1a and peripheral devices composed of at least one of a servo amplifier 2a, a spindle amplifier 3a and a remote I/O unit 4a.

Abstract: A synchronous control device which is provided with drive motors and a central control unit generating a synchronous reference signal and with which the drive motor is controlled to rotate synchronously with the synchronous reference signal supplied from the central control unit, which is provided with: device motor brakes for braking a rotation of the drive motor; machine home position detectors for detecting a rotation phase of the drive motor; and drive controlling means for controlling a drive motor in such a manner that the drive braking means is activated depending on a stop instruction supplied from the central control unit and a required rotation phase of the drive motor is stored; a comparison between the required rotation phase of the drive motor and the rotation phase thereof is performed at the time of re-start; and a home position alignment of the drive motor is performed at a start time of a subsequent operation.

Abstract: A drive unit for controlling a motor includes a position feedback device and a velocity noise filter. The position feedback device is operable to generate a position signal relating to a position of the motor. The velocity noise filter is coupled to the position feedback device and operable to filter the position signal over a predetermined number of samples to generate a velocity feedback signal for the motor.

Abstract: A circuit system that includes a sensor circuit for a sensor that detects the state of a motor is provided in an inverter unit for driving the motor. A 0V of the circuit system is connected with a shield braid of a shielded cable that connects the sensor circuit and the sensor. Further, the shield braid of the shielded cable is connected to an earth plate.

Abstract: A motor control system for controlling a motor includes control logic and a motor controller. The control logic is operable to generate a control signal at a first periodic time responsive to a synchronization signal. The motor controller is operable to generate a drive signal for the motor based on the reference signal at a second periodic time synchronized with respect to the first periodic time.

Abstract: A synchronization device particularly for at least two windshield wipers, comprising at least two wipers, each of which is composed of a blade that is kinematically connected to an electric motor or gearmotor in order to oscillate between two preset positions; elements for activating/deactivating the gearmotor; elements for signaling the transit of each one of the blades through a preset reference position; elements for controlling the signals and driving the activation/deactivation elements; elements for determining the wiping time for each one of the wipers; elements for calculating the lead time error of the at least one wiper that is faster with respect to the slower wiper of the at least two wipers; elements for calculating a correction time; elements for identifying the slower wiper and elements for applying each one of the correction times to the corresponding motor/gearmotor of the at least one faster wiper.

Abstract: The lighting fixture includes a housing having an interior cavity and a transparent cover. A color-changing electric light assembly is provided in the interior cavity. The light assembly emits a plurality of different colors of light through the transparent cover and cycles through the plurality of different colors of light to sequentially emit each of the plurality of different colors of light. A synchronization circuit responds to a timed interruption in the power for synchronizing the color-changing electric light assembly with a color-changing electric light assembly of another underwater lighting fixture connected to the same power.

Abstract: An underwater lighting fixture adapted for installation in a wall of a swimming pool. The lighting fixture includes a housing having an interior cavity and a transparent cover. A color changing electric light assembly is provided in the interior cavity. The light assembly emits a plurality of different colors of light through the transparent cover and cycles through the plurality of different colors of light to sequentially emit each of the plurality of different colors of light. An electrical conductor extends through the housing into the interior cavity for delivering power to the color changing electric light assembly. A synchronization circuit responds to a timed interruption in the power for synchronizing the color changing electric light assembly with a color changing electric light assembly of another underwater lighting fixture connected to the same power.

Abstract: A first drive voltage generating section corresponds to a first motor, and a second drive voltage generating section corresponds to a second motor. Each of the first drive voltage generating section and the second drive voltage generating section includes switching elements, an A/D converter, and an MPU. Each A/D converter samples an analog signal representing a load state of the corresponding motor. A clock circuit synchronizes the control periods of the drive voltage generating sections. Each MPU commands the corresponding A/D converter to sample the analog signal at timing where no switching is performed by any of the switching elements in the drive voltage generating sections. Therefore, the analog signals representing the load states of the motors are preferably sampled without being influenced by noise generated by switching.

Abstract: By controlling all motors so that they all decelerate at substantially the same rate, buckling of media in a media handling system is substantially eliminated on shutdown. Preferably, the deceleration rate of the highest inertia motor is used as the common deceleration rate.

Abstract: A method for controlling the rotation speed of a slave drive is described, where a reference rotation speed and a reference position is provided to a controller. The controller determines an estimated acceleration curve for the slave drive based on an instantaneous rotation speed, an instantaneous position and a maximum rotation-speed-dependent acceleration of the slave drive. The estimated acceleration curve for the slave drive is hereby determined so that after a compensation time, the rotation speed of the slave drive is equal to the reference rotation speed and the position of the slave drive is also equal to an expected reference position, which is determined by the controller based on the reference position, the reference rotation speed and the compensation time.

Abstract: A synchronization control device and a synchronization control method are provided in which it includes controllers Am and As1 of a master section and a slave section for accurately synchronizing rotational frequency and rotation phases of driving electric motors Mm and Ms1. The controller As1 includes rotational frequency detectors Ss1, Fs1, a master phase counter Cm1, and a slave phase counter Cs1, and detects at all times both of a rotational frequency and a rotation phase of the electric motors Mm of the master based upon an output of the rotary encoder Pm, and further detects at all times both of a rotational frequency and a rotation phase of the electric motor Ms1 of the slave.