Abstract: A switch for a variable-speed induction motor includes conductive connecting pieces, a rotary member, and a driving unit. The connecting pieces are mounted in a housing, are adapted to be connected to the induction motor, and have distal contact parts that surround an axis of the housing. The distal contact parts of any two of the connecting pieces form either an angular or height difference therebetween with respect to the axis. The rotary member is rotatable about the axis inside the housing, and is formed with contacting regions that are arranged along the axis and that are in sliding contact with the distal contact parts. The driving unit is operable so as to drive rotation of the rotary member about the axis such that the connecting pieces are bridged selectively and electrically by the contacting regions of the rotary member for varying the speed of the induction motor.

Abstract: In a control apparatus for a synchronous motor, a coordinate converter converts a detected current into a current on rotational biaxial coordinates (d-q axis). A current controller outputs a voltage command on the coordinates so that the current follows a current command on the coordinates. Another coordinate converter converts the voltage command into three-phase voltage commands. An adaptive observer calculates an angular frequency so that a q-axis component of an estimated rotor magnetic flux is zero. An inverter applies a voltage to the motor based on the voltage command.

Abstract: A synchronous motor controlling apparatus which can be applied to the carrier synchronized position estimating method as well and have protection-related functions such as detection of inverted magnetic pole position of a motor in a simple method, and an electric motor using the synchronous motor control apparatus. A controller controls a voltage applied to an AC motor with a PWM signal. A magnetic pole position detector of the controller detects a current of the AC motor to estimate a pole position of the AC motor. A fault detector detects a fault in the estimated magnetic position of the AC motor.

Abstract: In an electric motor apparatus of the present invention, both of energized spiral wires 17A and 17B for a first system 18A and a second system 18B cooperate to rotate the rotor 25 in a normal condition, however, when it is happened an abnormal condition in one of the first system and the second system, the energized spiral wires of the other system rotate the rotor 25 so that the present invention can prevent the rotation of the electric motor 14 from stopping just after the abnormal condition in either of the systems to achieve a fail-safe function. Therefore, the present invention can decrease a number of parts in comparison with the conventional apparatus having two actuators to restrain an increase of the cost and to achieve a compact structure.

Abstract: A magnetic flux estimator 7 of a controller used for sensorless vector-controlling of an induction motor computes an estimated speed ?rest and an estimated phase ?lest from input ?-phase and ?-phase voltage instructions V?*, V?* and ?-phase and ?-phase currents is?, is?. A speed corrector 8 receives these information items and determines a difference between a differential value output from a phase estimator and an additionally input slip angular speed; that is, a deviation ??res. Further, a primary delay integral value is determined by subtracting a slip angular frequency ?s from the deviation, and the primary delay integral value is multiplied by a correction gain, to thereby produce a correction to be made on the estimated speed ?rest. Thus, a more accurate estimated speed ??rest is obtained.

Abstract: A motor abnormality detection apparatus is capable of performing the abnormality detection of a motor (5) without supplying a special electric current thereto for abnormality detection in an ordinary control state. A motor control device (100) controls the motor (5) through vector control which is described by a two-phase rotating magnetic flux coordinate system having the direction of a field current as a d-axis direction and a direction orthogonal to the d-axis direction as a q-axis direction. A motor abnormality detection part (100h) (100h) performs an abnormality determination of the motor based on target impression voltages (Vd*, Vq*) impressed on the motor (5).

Abstract: A starting circuit for an induction motor is provided whereby a stationary rotor flux is established then a stored charge supplied to a motor winding in order to provide a starting torque. Before applying a mains power supply to the motor after the starting torque has been applied, a back EMF is sensed, directly or indirectly, to provide an indication that the rotor is turning before the mains supply is connected to the motor. This provides a reliable and simple method for ensuring that a mains supply may be safely connected to the motor.

Abstract: In a brushless motor control method and a brushless motor controller in accordance with the present invention, a rotor rotation position detection means detects the time of the intersection of a detected induced voltage and an induced voltage reference value. In addition, a motor speed calculation means calculates the rotation speed of a brushless motor on the basis of the interval of the intersection times detected by the rotor rotation position detection means. Furthermore, a speed control means outputs a duty factor index on the basis of the deviation between the command speed and the rotation speed of the brushless motor. Still further, a switching signal generation means outputs switching signals to groups of switching devices on the basis of the rotation speed and the duty factor index at the time of the intersection.

Abstract: A controller for a vector control of an induction motor, which is capable of easily determining a rotor resistance for use in calculation of a slip frequency. A temperature sensor is provided for detecting a temperature of a stator. Information on relation between the rotor temperature and the rotor resistance predetermined based on measurement is stored in a table. In driving the induction motor, the rotor resistance for the stator temperature detected by the temperature sensor is read from the table. A torque command I2 is divided by a magnetic flux command ?2 and the obtained quotient is multiplied by the read value of the rotor resistance to obtain the slip frequency ?s, so that the vector control is performed based on the obtained slip frequency ?s. The value of the rotor resistance is easily determined by simply referring the table without complicated calculation.

Abstract: A motor drive method for a motor driver having output circuits each including upper and lower side switching elements connected in series, and a current detection resistance connected in series with the output circuits in common. The motor drive method includes the steps of: turning ON a switching element on one side of one of the output circuits for a time period corresponding to a predetermined electrical angle; and repeatedly switching switching elements on the other side of a plurality of output circuits among the remaining ones of the output circuits. In the switching step, each of a plurality of periods obtained by dividing the time period corresponding to the predetermined electrical angle includes a first period in which one of the switching elements to be switched is turned ON and a second period in which another one of the switching elements is turned ON.

Abstract: An HVAC system has at least one variable speed controller for an AC induction motor, especially of the Permanent Split Capacitor (PSC) type. The variable speed controller provides switched power via a modulating triac to the main coils of the motor and constant power via an on/off triac to the auxiliary coils during operation. A large value capacitor is placed in line with the auxiliary coils to reduce power consumption and current draw over that of known systems. Power to the motor can be turned off to provide for motor speed sensing through monitoring the frequency of a generated voltage when the power is turned off. Frequency-based motor speed sensing is accomplished by shutting off all current to the motor and measuring zero crossings on the generated voltage of the decaying magnetic field. The controller can be easily retrofitted onto existing motors. An optional controller bypass is provided to run the motor at rated speed in case of controller failure.

Abstract: A system and method for controlling an electric motor using real time predictions of motor capability based on thermal modeling and measurements is provided. The invention includes controllers for receiving and processing system input signals, strategies for: determining a maximum energy amount that can be put into the motor before the motor reaches a maximum allowable temperature; determining a motor power assist value that the motor can provide in a predetermined period of time before the motor reaches the maximum allowable temperature; determining a battery power assist value; determining a maximum power assist value that is the minimum of the motor power assist value and the battery power assist value; and comparing the maximum power assist value to a driver demand signal. Strategy outputs can be sent to a vehicle system controller and/or a power assist gauge.

Abstract: A controller for a motor and a method for controlling the operation of the motor. The controller includes a model of the motor, where the model is utilized to determine modeled values of first and second motor variables. An estimated value of slip is adjusted based at least in part on a comparison of the modeled value of the second motor variable and an estimated value of the second motor variable which is based at least in part on a value of bus voltage and a value of bus current. As the estimated value of slip is adjusted, the modeled values are updated and the voltage utilized to energize the motor is thereby updated to provide control of the motor based on the control of the first motor variable.

Abstract: An electrical machine comprises a rotor without windings, a stator having an armature winding 24, 25 and a field winding 10 for generating a magnetomotive force in a direction extending transversely of the magnetomotive force generated by the armature winding. An electronic circuit 40 is provided for controlling the current in the armature winding 24, 25 such that periods in which a magnetomotive force in one direction is associated with a first current pulse alternate with periods in which a magnetomotive force in the opposite direction is associated with a second current pulse. A position sensor is provided for monitoring the rotational position of the rotor and for supplying output signals dependent on the speed of rotation of the rotor. Furthermore a control system 32 supplies control signals to the circuit 40 to control the current in the armature winding 24, 25.

Abstract: There are performed converting electric currents Iu, Iv, and Iw flowing through the synchronous motor into a d-axis actual current Idfb and a q-axis actual current Iqfb on rotational coordinate axes which rotate synchronously with a rotor magnetic flux vector, on the basis of an actual position ? of the rotor of the synchronous motor; estimating a d-axis simulated current Idob and a q-axis simulated current Iqob on the basis of the d-axis actual current Idfb, the q-axis actual current Iqfb, a d-axis actual voltage command Vdref, and a q-axis actual voltage command Vqref; generating a d-axis actual voltage command Vdref and a q-axis actual voltage command Vqref on the basis of a d-axis current command Idref, a q-axis current command Iqref, a d-axis simulated current Idob, and a q-axis simulated current Iqob; and converting the d-axis actual voltage command Vdref and the q-axis actual voltage command Vqref into actual voltage commands Vuref, Vvref, and Vwref on the basis of the actual position ? of a rotor of t

Abstract: A coil winding number variable type motor for varying a cooling and heating capacity of a reciprocating motor includes: a plurality of coils separately wound and connected in series to each other so as to vary turn ratio among motor coils; a plurality of relays respectively connected between adjacent coils among the plurality of coils; and a relay controller for outputting and ON/OFF control signal for varying the winding number of the motor coil and controlling the relays according to a change in a load and a power supply voltage. The coil wound in the motor of the reciprocating compressor is divided into the main coil and the plurality of sub-coils and the winding number of the motor coil is varied by itself to control the stroke of the reciprocating compressor, thereby effectively coping with the change in the voltage or the load.

Abstract: A motor driver circuit including an inverter, a motor-drive-current detector, a current detector, and a controller operable to calculate a d-axis current difference between the detected d-axis current and a commanded d-axis current value, and a q-axis current difference between the detected q-axis current and a commanded q-axis current value. The controller is further operable on the basis of the calculated d-axis and q-axis current differences, to calculate a d-axis difference signal which is not influenced by a q-axis input voltage of the motor and which is influenced by a d-axis input voltage of the motor, and a q-axis difference signal which is not influenced by the d-axis input voltage and which is influenced by the q-axis input voltage. The controller controls the inverter, so as to zero the d-axis and q-axis difference signals.

Abstract: Disclosed are a flux observer and a sensorless control system of a synchronous reluctance motor. The flux observer includes an estimated flux output unit, a measured flux output unit, and a fixed/rotational coordinate converter. The flux observer estimates a flux of a synchronous reluctance motor by removing higher harmonic components of a current in a rotational coordinate system which flows into the motor. The measured flux output unit measures a flux in a fixed coordinate system by combining a voltage in the fixed coordinate system, which is applied to the motor, and a current in the fixed coordinate system, from which higher harmonic components are removed, with the estimated flux outputted from the estimated flux output unit. The fixed/rotational coordinate converter converts the measured flux outputted from the measured flux output unit to a measured flux in the rotational coordinate system.

Abstract: A method and apparatus for use with a controller that uses a flux angle position value to control a three phase induction machine, the method for determining an instantaneous flux angle position value in the machine where the machine is characterized by a system specific dominant harmonic frequency number DH that is at least two, the method comprising the steps of injecting a high frequency voltage signal having a high frequency value into the machine thereby generating a high frequency current within the stator windings, obtaining a high frequency feedback signal from the machine, mathematically combining the high frequency value and the dominant harmonic number DH to provide an instantaneous modified angle, using the feedback signal to identify X consecutive calculating instances during each Y consecutive feedback signal cycles where Y is at least two, at each of the X different calculating instances, identifying an instantaneous flux angle position value by mathematically combining a shift angle with the i

Abstract: A method for providing additional dc inputs or outputs (49, 59) from a dc-to-ac inverter (10) for controlling motor loads (60) comprises deriving zero-sequence components (Vao, Vbo, and Vco) from the inverter (10) through additional circuit branches with power switching devices (23, 44, 46), transforming the voltage between a high voltage and a low voltage using a transformer or motor (42, 50), converting the low voltage between ac and dc using a rectifier (41, 51) or an H-bridge (61), and providing at least one low voltage dc input or output (49, 59). The transformation of the ac voltage may be either single phase or three phase. Where less than a 100% duty cycle is acceptable, a two-phase modulation of the switching signals controlling the inverter (10) reduces switching losses in the inverter (10). A plurality of circuits for carrying out the invention are also disclosed.

Abstract: The present invention enables modulated wave signals having extremely small waveform distortion to be generated using a relatively simple circuit, and thereby it is possible to hold down vibrations and noise of a motor, which are attributable to torque ripples. In order to remove defects of the conventional techniques, the circuit generates a plurality of trapezoidal wave signals having at least two constant levels based on position sensing signals of magnetic pole of a motor, generates quasi-sinusoidal wave signals at a quasi-sinusoidal wave modulator based on the plurality of trapezoidal wave signals, and compares the quasi-sinusoidal wave signals with a carrier wave so as to perform PWM control of an inverter.

Abstract: An induction motor drive system and method estimates a motor power factor based on the AC power output to the motor phase windings and estimates the rotor speed based on the estimated power factor. The estimated rotor speed is compared to a rotor speed command signal to generate a speed error, and the voltage and frequency input to the motor are adjusted in response to the speed error. Rotor speed is estimated based on estimated rotor slip, which is estimated based on the applied voltage, frequency, estimated power factor and estimated motor power.

Abstract: An interface circuit for actuating an electrical consumer, especially a pole-changing rotary-current induction motor, with a first contact element assigned to a signal line carrying an alternating voltage signal to generate at least two different control signals. A circuit arrangement is provided for actuating an electric motor, especially a pole-changing rotary-current induction motor, with a control switch element having an aforementioned interface circuit, which is connected via a signal line to a motor control of the electric motor.

Abstract: A longer life, low cost tool and tool holder enabling change of posture with respect to a spindle, having a high machining accuracy of a workpiece, and resistant to generation of vibration or heat, provided with a working tool for processing a workpiece, a motor having an output shaft to which the working tool is connected and rotating the working tool, a first holder for holding the working tool and the motor, a mount attached to the spindle, a generator to which rotational force is transmitted from the spindle through the mount and generating electric power for driving the motor, a second holder for holding the mount rotatably, holding the generator, and engaged with a nonrotating portion of the machine tool, and a posture adjustment mechanism which connects the first holder and the second holder and is able to change the posture of the working tool with respect to the spindle.

Abstract: A control apparatus of a synchronous reluctance motor includes a torque current correction unit (16) that generates a torque current command tracing a load torque so as to make the output torque of the motor coincide with the load torque. The control apparatus may further include a position and speed estimation unit (13) that estimates the position and speed based on three phase voltage equation to improve control performance in a voltage saturation state.

Abstract: A feedback response signal in a motor drive system in response to injection of a high frequency carrier signal provides information for determining motor position and demagnetization detection. The high frequency carrier signal excitation can be voltage or current based. The feed back signal is processed with various filtering techniques and phase detection to obtain the desired information. Both uniform and localized demagnetization of the motor is detected by examining the saturation saliency of the stator iron for a lack of position dependent information or large DC offsets. The technique provides good position information for the motor while providing an indication of motor health.

Abstract: A technique for controlling an AC motor. An electric power is output to the AC motor. The output current of an electric power converter is controlled based on a difference signal of an output current detection signal and a current command signal of the electric power converter. When the AC motor is in a free run condition, current control is conducted by forcing the current command signal to be zero so that a current in the AC motor is made zero. The amplitude and phase and angular velocity of a residual voltage of the AC motor are found based on a calculated output voltage command.

Abstract: Systems and methods for controlling and/or calculating the torque for a field oriented induction motor operating at a given stator frequency. The systems and methods include calculating the torque using a first algorithm when the motor is at or below a first predetermined stator frequency, a second algorithm when the motor is at or above a second predetermined stator frequency, and a third algorithm when the motor is between the first predetermined stator frequency and the second predetermined stator frequency.

Abstract: A drive unit for a brushless fan motor capable of easily controlling the rational speed of the motor without using PWM control. A power control circuit is provided for controlling the rational speed of the rotor by controlling the on/off operation of power feed semiconductor switch. The actual rotational speed of the rotor is compared with the target rotational speed. Based on the compared values, the turn-off time of the power feed semiconductor switch is controlled so that the rotational speed of the rotor may reach the target rotational speed fast and smoothly.

Abstract: One embodiment of the present invention is a method to control input to an alternating current (AC) induction motor from a power supply that includes steps of: (a) determining a measure of reactive power (VAR) in two input lines to the motor during a time period; and (b) maintaining an SSR (solid state relay) connected in series between the power supply and the motor in a non-conducting state for a subsequent time period, the length of which subsequent time period is determined by analyzing the measure of VAR.

Abstract: A provide a position-sensorless motor control apparatus comprises a salient-pole AC motor 2, a PWM inverter 3 for applying voltage to the AC motor 2, and a controller 1 for controlling the PWM inverter 3 by means of PWM signals, wherein the controller 1 has a position estimation means 11 which detects motor inductance in the pre-determined direction to the vector direction of the current that flows through the AC motor 2 and estimates the AC motor's rotor position based on the motor inductance.

Abstract: Processor-based field oriented control for brushless doubly-fed induction machine having first and second polyphase stator windings is programmed to operate the machine in various modes, as a motor or a generator, with bumpless switching between operating modes. An electronic power converter controls a current supplied to the first stator winding to control the torque of the machine, with the second stator winding selectively connected to an AC line. Stationary coordinates for in-phase and quadrature current commands are coordinate transformed using a voltage vector for voltage induced on the first polyphase stator winding to control current in the first stator winding, with or without a position sensor. The electronic power converter controls the voltage supplied to the first stator for generating, with the second stator selectively connected to a load. The machine can also be controlled to operate as a singly-fed motor at lower speeds, with the second stator winding shorted.

Abstract: A method and apparatus for regulating a harmonic current component of an inverter fed motor drive system comprises measuring a phase current of the motor, substantially eliminating the fundamental component of the phase current, demodulating the phase current having the fundamental component substantially eliminated to produce a first current signal and providing the first current signal to a PWM control input of an inverter drive of the inverter fed motor drive system to affect the inverter output voltage by driving a first harmonic current of the motor substantially to zero thereby to achieve harmonic current control. More accurate, estimated motor voltages can also be provided by the system.

Abstract: A control device for an induction motor controlling torque generation of the induction motor with high precision includes a rotation speed detector which detects the rotation speed of the induction motor, a current detector which detects a primary current of the induction motor; an amplifying unit which amplifies deviation between an estimated primary current obtained from a magnetic flux observing device and the primary current obtained from the current detector; a magnetic flux observing device which estimates an estimated secondary magnetic flux and an estimated primary current of the induction motor based upon the rotation speed obtained from the rotation speed detector, the primary voltage of the induction motor and the deviation signal obtained from the amplifying unit, and a control unit which controls a voltage applied to the induction motor based upon the estimated secondary magnetic flux obtained from the magnetic flux observing device.

Abstract: A system and method for predicting mechanical failures in machinery driven by induction motors by using the motor as a diagnostic tool to detect present mechanical disturbances. The motor is monitored during operation to avoid down-time. The motor's torque fluctuations are used as an indicator of early-stage mechanical failures in the machinery. The motor's torque fluctuations are determined using indirect sensing techniques that are less expensive and less intrusive than previously known. More specifically, torque is derived from easily and inexpensively measurable parameters, such as motor slip and phase angle. Current operation is compared to known normal operation. Variations of the motor's characteristics from the known baseline indicate an actual or approaching mechanical failure. “Experimental Fractals” are disclosed that visually represent a current state of the monitored machinery and allow for visual comparison to a baseline for detection of mechanical failures.

Abstract: A method for utilizing a three-wire programming box with a motor control circuit is provided. The method includes providing a three-wire to two-wire interface. The method further includes connecting the three-wire to two-wire interface between the three-wire programming box and the motor control circuit such that the three-wire programming box communicates bi-directionally with the motor control circuit utilizing less than three connections between the three-wire to two-wire interface and the motor control circuit.

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: To provide a control circuit or the like of a brush-less motor capable of properly controlling current of motor windings by detecting positions of magnetic poles of a rotor at a rotational frequency of the rotor from low rotation which cannot lock a PLL circuit to steady-state rotation for rotating at high speed. Positions of magnetic poles are detected by a change in a magnetic flux (magnetic flux signal) of motor windings caused by rotating a rotor having the magnetic poles, thereby, a synchronizing signal (ROT signal) in synchronism with rotation of the rotor is generated.

Abstract: A method for controlling an induction motor using an equivalent circuit model, the equivalent circuit having a real component and an imaginary component, is disclosed. The method instead of measuring a plurality of induction motor parameters, the real and the imaginary component of the induction motor impedance are calculated based on the measured phase currents and voltages. The invention calculates a first control function based on the real component of the induction motor impedance, and a second control function based on the imaginary component of the induction motor impedance, and adjusts the induction motor excitation frequency until the first control function is approximately equal to the second control function. After the excitation frequency is determined, the motor torque is calculated by taking the square of motor voltage in the d-q reference frame.

Abstract: A battery-supplied inverter (1) for a brushless electric motor (2) having a plurality of phase windings (3a, 3b, 3c), which is connected in a supply current delta connection (4a) via two supply current lines (5) with a supplying battery (6) having a plurality of battery cells (8), wherein it is connected with the battery (6) in at least one second supply current delta connection (4b, 4c) via supply current lines (5).

Abstract: A power controller for applying power to an induction motor or similar AC load has a variable drive circuit for staring and switching a portion of the AC input line power. In one mode, the input line power is fed straight through to the load. In another mode, the AC waveform is reshaped to improve the power factor or to boost its RMS value, e.g., for brownout protection. In a further mode the output power can be provided at a different frequency from the input line power. Vector control increases efficiency through power optimization, with sensing of load requirements. Sensing of regeneration pulses at the commencement of a half cycle can be employed for direct sensing of motor speed or load.

Abstract: In the embodiments described in the specification, a permanent magnet machine includes a stator having windings which intercept flux received from peripheral pole pieces in a rotor generated by permanent magnets disposed between the pole pieces. In order to control the flux passing through the stator windings, flux shunts are provided between the pole pieces and a winding on the core of each flux shunt generates flux in the shunt in proportion to current supplied to the winding so as to decrease the flux from the magnets which can be diverted from the pole pieces through the shunt. Current is supplied to the flux shunt windings in accordance with the instantaneous difference between the wave shape of the output from the machine and a desired wave shape stored in a control unit. An encoder supplies a signal to the control unit indicating the instantaneous position of the rotor with respect to the stator.

Abstract: Disclosed is an apparatus controlling an operation of a motor and control method thereof enabling to prevent a driving force of the motor from being reduced and actuate the motor for hours stably when a washing machine is operated for hours. The present invention includes the steps of detecting a phase voltage value and a phase current value applied to the motor between forward and backward revolution sections of the motor, calculating a phase resistance value based on the detected phase voltage and current values, and controlling the operation of the motor by controlling a voltage applied to the motor in accordance with the calculated phase resistance value.

Abstract: Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.

Abstract: Method/apparatus for controlling input to an AC induction motor from a power supply that determines a measure of reactive power in two input lines to the motor from the power supply, and uses that measure of reactive power to control an SSR in series between the power supply and the motor. In one arrangement, a voltage difference between the two input lines and a current in one of the lines is used to determine the measure of reactive power.

Abstract: Object of the present invention is to distribute signals indicating angular position of a rotor from a controller for a brush-less motor to another control device. A controller for driving a brush-less motor has a magnetic-pole detecting circuit (9) that receives from a Hall-effect semiconductor disposed in a motor roller (4) sequential (pole position-representing) signals relating to a rotor's position. These signals are converted into pulses and then supplied to a current-controlling circuit (8), so that currents to stators are controlled based on the signals from the detecting circuit (9) so as to drive the motor roller. A sequencer (20) supplies to a controlling circuit (7) “ON/OFF” and other commands, that are then processed in this circuit and fed to the current-controlling circuit (8) for driving the motor.

Abstract: The present invention includes an induction motor and a system for controlling the induction motor including a battery providing a DC voltage and an inverter coupled to the induction motor and the battery, wherein the inverter is adapted to drive the induction motor from the battery. A motor controller is adapted to calculate a flux current and a slip frequency in response to an induction motor speed. The motor controller is further adapted to operate in one of a current control mode or a slip control mode. The motor controller is adapted to cause the slip frequency to increase by a slip decremental in a transition phase from the current control mode to the slip control mode, and further adapted to cause the slip frequency to increase by a slip incremental in a transition phase from the slip control mode to the current control mode.

Abstract: A method for use with an adjustable frequency controller to deliver current to an electromagnetic load including a stator and a rotor, the method for identifying a flux current estimate and comprising the steps of (a) identifying a rated torque value; (b) providing an initial q-axis current estimate; (c) using the q-axis current estimate to identify a d-axis current estimate; (d) mathematically combining the d-axis current estimate and the q-axis current estimate to identify a torque estimate; (e) comparing the rated torque value to the torque estimate; (f) where the torque estimate is similar to the rated torque value skipping to step (i); (g) altering the q-axis current estimate; (h) repeating steps (c) through (f); and (i) storing the d-axis and q-axis current estimates as flux and torque current values for subsequent use.

Abstract: The present invention is related to an operating device (200) for driving and controlling the opening and closing of an electrical high voltage or medium voltage switching apparatus, such as a switch or a circuit breaker. The operating device comprises a rotating electric machine (201) which is operatively connected to a mobile contact (203) of the switching apparatus. The rotating electric machine (201) operates the mobile contact via a mechanical coupling (202) upon receiving control signals (208) from a control unit (205). The rotating electric machine (201) may, upon a decelerating motion of the mobile contact (203), transform the kinetic energy of the mobile contact (203) into electrical energy which can be transferred to a suitable energy storage or supply unit (204). The operating device according to the invention is especially suited to operate circuit breakers of all types.

Abstract: A modular motor controller family comprises a housing. Solid state switches are selected from one of plural switch sizes for controlling a desired voltage and current range. The switches are mounted in the housing for connection between an AC line and motor terminals for controlling application of AC power to the motor. A logic circuit board is mounted in the housing including logic circuitry for commanding operation of the solid state switches independent of the selected switch size. An interface circuit board selected from one of plural configurations is mounted in the housing and includes interface circuitry connected between the logic circuitry and the solid state switches. The interface circuitry is selected to interface with the selected switch size according to the desired voltage and current range.