Abstract: A propulsion system for a device includes an electric motor configured to generate torque to propel the device. The electric motor includes a stator and a rotor with one or more permanent magnets. A controller is in communication with the electric motor and has recorded instructions for a method for minimizing demagnetization in the one or more permanent magnets. The controller is adapted to select a starting point and an intermediate point on a current trajectory in a stator current graph. The controller is adapted to obtain a final point on the stator current trajectory based on a comparison of the intermediate point and a predetermined voltage limit. A demagnetized torque capability is generated based on the final point on the current trajectory.

Abstract: A position sensor mounted in an actuator includes a magnetic detecting element for detecting the position of a shaft, and a temperature detecting element for detecting intra-sensor temperature which is used for correction of the temperature characteristics of the magnetic detecting element, the magnetic detecting element and the temperature detecting element being built therein. A control device for the actuator acquires both the temperature-corrected position of the shaft and the intra-sensor temperature from the position sensor, and uses them for control of the actuator.

Abstract: A maximum current value determination unit determines the maximum current value of a permanent magnet synchronous motor in order to prevent irreversible demagnetization of a permanent magnet of the permanent magnet synchronous motor from occurring due to transient current occurring at the time of short-circuiting of three phases, based on one of a set of irreversible demagnetization causing current value corresponding to permanent magnet temperature and the transient current occurring at the time of the short-circuiting of three phases, and a set of irreversible demagnetization causing magnetic field intensity corresponding to the permanent magnet temperature and demagnetization field intensity of the permanent magnet of the permanent magnet synchronous motor occurring at the time of the short-circuiting of three phases.

Abstract: A motor includes a frame, a shaft rotatably mounted onto the frame, and at least one disc mounted onto the shaft. At least one permanent magnet is mounted on the disc, and at least one electromagnet and at least one coil are mounted to the frame in rotational magnetic proximity to the permanent magnet. A battery is connectable to the electromagnet and the coil for energizing the electromagnet and for receiving electrical current from the coil for charging the battery. A relay switch controls the transmission of electrical power from the battery to the electromagnet. A sensor generates a signal to the relay switch to activate electrical power to the electromagnet upon sensing that the permanent magnet is positioned with respect to the electromagnet such that a magnetic force generated by the electromagnet would be effective for inducing movement of the permanent magnet and consequent rotation of the disc.

Abstract: A system and method for the automatic control of wheel brake-slip in a motor vehicle with an electric drive (2), including the following steps: detecting a brake signal (14) by means of a slip control device (9), at which point the slip control device (9) generates an electric drive signal (15) and a friction brake signal (16) for the automatic control of a predetermined slip value of a wheel (1) of the motor vehicle, transmitting the electric drive signal (15) to an electric drive control device (6) and transmitting the friction brake signal (16) to a friction brake control device (12), at which point a friction brake control device (12) activates a friction brake (10) of the wheel (1) according to the friction brake control signal (16) to generate friction brake signal (16) to generate friction brake torque and an electric drive control device (6) activates electric drive (2) according to electric drive signal (15) to generate electric drive torque.

Abstract: An electric power plant with a gas turbine engine that drives an electric generator, where the generator is a co-rotating electric generator positioned between the turbine and the compressor such that the turbine drives the compressor through the electric generator, and where the co-rotating generator includes a rotor and a stator that both rotate in the same direction but with a differential rotational speed of around 3000 or 3,600 rpm in order to produce 50 or 60 hertz electrical power. A wire brush makes contact with a rotating surface of the generator to carry away electricity, and the wire brush is continuously fed to make up for wear.

Abstract: Methods and apparatus are provided that include or provide a first three-phase induction machine including stator windings, a second three-phase induction machine including stator windings, wherein the stator windings of the first machine are coupled in series with the stator windings of the second machine, and an inverter circuit that provides a three-phase output signal coupled to the stator windings of the first machine. Other aspects are also provided.

Abstract: At least two asynchronous AC induction electrical machines in series connection with the power source are respectively made with the main winding and control winding for operating the electrical machines, wherein the individually driven loading operations of the two electrical machines in cross-interlockingly series connection being series connected with the power source are led by the changes of individual electrical machine driving loading statuses to appear variable impedance operation so as to change the end voltage ratio between individual electrical machines in cross-interlockingly series connections.

Abstract: A distributed electromechanical actuation system including multiple electromechanical actuators intended to operate together in a synchronous (or near synchronous) manner. Each individual actuator is powered by one or more induction motors or other appropriate motor such as a stepper motor. The induction motors are designed to have a very high pullout torque with very low slippage to the pull out point. The group of actuators is controlled from a single controller (e.g., an induction motor controller) that utilizes a Volts per Hertz type of open loop control where the bus voltage and frequency are controlled to assure that the motors always operate on the low slip side of the pull out point performance curve.

Abstract: This motor control apparatus is provided with: a reduced energy calculation device that calculates a reduced energy that is produced when a drive mode of a hybrid vehicle is shifted from a drive mode driven by a motor to a drive mode driven by an internal combustion engine and if the phase of the motor is changed from the present phase to the arbitrary required phase; a displacement energy calculation device that calculates a displacement energy that is produced when the present phase is changed to the arbitrary required phase; and a phase change permission device that compares the reduced energy and the displacement energy, and permits changing from the present phase to the required phase when it is determined that the reduced energy is greater than the displacement energy.

Abstract: The invention relates to a continuously controllable gear comprising a driving rotor rotatably driven by a power source which is provided with magnets uniformly distributed on the periphery thereof and produces, during the rotation thereof, a magnetic multipolar field in an ambient space rotating therewith. Said driving rotor is surrounded in the radial direction outwards with the primary air gap of a coaxial field concentrator which forms magnetoconductive pole shoes and is separated from a coaxial stator by means of a secondary air gap. The grooves of the stator are provided with sequentially short-circuitable windings.

Abstract: Methods and apparatus are provided that include or provide a first three-phase induction machine including stator windings, a second three-phase induction machine including stator windings, wherein the stator windings of the first machine are coupled in series with the stator windings of the second machine, and an inverter circuit that provides a three-phase output signal coupled to the stator windings of the first machine. Other aspects are also provided.

Abstract: There is provided a controller for a motor capable of changing the phase difference between two rotors that can prevent demagnetization of permanent magnets or the rotors. The motor has two rotors each having a permanent magnet and phase difference changing driving means for changing the phase difference between the rotors. The controller has a demagnetization determining means for determining whether or not demagnetization of the permanent magnets of the rotors occurs during operation of the motor, and rotor phase difference controlling means for controlling the phase difference changing driving means to change the phase difference between the rotors from a current phase difference to a phase difference that results in a higher strength of a composite field of the permanent magnets if the result of determination by the demagnetization determining means is positive.

Abstract: A controller for a motor carries out field weakening control by using a simple construction to change the phase difference between two rotors, which are disposed around a rotating shaft, without depending on the number of revolutions of a motor. The controller for a motor includes a field weakening current calculator for calculating a field weakening current command value on the basis of the radius of a target voltage circle, a d-axis voltage command value, and a q-axis voltage command value, a rotor phase difference command value determiner for determining a command value of a rotor phase difference on the basis of the field weakening current command value, and a current command value determiner for determining a d-axis current command value and a q-axis current command value on the basis of the rotor phase difference command value and a torque command value.

Abstract: There is provided a controller for a motor capable of changing the phase difference between two rotors that can prevent demagnetization of permanent magnets or the rotors. The motor has two rotors each having a permanent magnet and phase difference changing driving means for changing the phase difference between the rotors. The controller has a demagnetization determining means for determining whether or not demagnetization of the permanent magnets of the rotors occurs during operation of the motor, and rotor phase difference controlling means for controlling the phase difference changing driving means to change the phase difference between the rotors from a current phase difference to a phase difference that results in a higher strength of a composite field of the permanent magnets if the result of determination by the demagnetization determining means is positive.

Abstract: A change in torque produced by a motor having two rotors is reduced when the motor operates in a low-velocity and low-torque operational state. The motor has a first rotor and a second rotor, each of which has a permanent magnet, and an output shaft capable of rotating integrally with the first rotor. The second rotor can relatively rotate with respect to the first rotor by a driving force from a phase difference changing driving device, and the phase difference between the rotors (rotor phase difference) can be changed by the relative rotation of the second rotor with respect to the first rotor. When the values of the torque and the rotational velocity of the motor lie within a predetermined region in the proximity of 0, the phase difference changing driving device adjusts the rotor phase difference to a predetermined phase difference for which the strength of a composite field of the permanent magnets is lower than a maximum strength.

Abstract: A rotary electric machine having a plurality of rotors is driven by a compound current. A voltage to be applied to a stator of the rotary electric machine is in the form of a compound rectangular or stepwise voltage composed of a plurality of superposed components each of which is a rectangular or stepwise wave having a frequency corresponding to the revolution speed of a unique one of the rotors.

Abstract: A motor/generator comprises a stator (2) having plural coils (C1-C14), and plural rotors (3, 4) disposed coaxially with the above-mentioned stator and driven by a compound current. The phase difference between the currents (70, 71) driving the rotors (3, 4) is arranged to be other than 180 degrees. Thereby, the utilization factor of the voltage of the direct current power supply (10) is improved.

Abstract: An inverter (23) generates a composite current comprising an electrical current for a first rotor (4) and an electrical current for a second rotor (3). A microprocessor (22) controls the inverter (23) so that the average value of the composite current is smaller than the sum of the average values of the respective currents.

Abstract: A transformer outputs different (high or low) secondary voltages. A switch outputs high or low secondary voltage according to a mode signal. An electric power converter including a rectifying circuit and a switching circuit either charges a smoothing capacitor with an output of the switch or discharges the smoothing capacitor to supply a regenerative current toward the transformer with a power fact improved. An phase signal generation circuit generates PWM or PAM phase signals in accordance with the mode signal. An inverter circuit generates driving signals supplied to the motor in response to the phase signals from power from the smoothing capacitor. A mode determining circuit determines one of modes to generate the mode signal in accordance with a speed command signal and acceleration/deceleration which is indicated by the rotating speed signal and the rotating speed command signal.

Abstract: In a first type of variable speed electric motor, two coaxial shafts are mounted in a housing. Two rotors are mounted on each shaft. Two stators are mounted in the housing. Each of the stators is in operative association with a rotor mounted on a different one of the shafts. The remaining two rotors are in operative association with each other and form a converter motor. In the second type of variable speed electric motor, two parallel shafts are mounted in a housing. A support is mounted for rotation around the first shaft. Two rotors are mounted on the first shaft. A stator is mounted in the housing in operative association with one of the rotors mounted on the first shaft. A third rotor is mounted on the support in operative association with the other rotor mounted on the first shaft. The support is geared to the first shaft through idler gears mounted on the second shaft.

Abstract: A variable speed rotary electric machine comprises a stator composed of a stator core and first and second stator windings wound on the stator core, and a cage rotor mounted rotatably within the stator and composed of a rotor core and rotor conductor disposed in a squirrel-cage configuration. The first stator winding is connected to an AC power supply of a fixed frequency. The second stator winding is connected to a power supply of a variable frequency. The first and second stator windings are so wound as to form, respectively, numbers of poles differing from each other. The rotor conductors of the cage rotor are electromagnetically coupled with the magnetic flux generated by the first and second stator windings, respectively, and so disposed as to form a number of poles which is intermediate between the number of the poles formed by the first stator winding and the number of poles formed by said second stator winding.