Abstract: The invention relates to a method (19) for starting an electric single-phase induction motor (1), wherein during a start-up interval of the start-up cycle for starting said electric motor (1), the frequency (fref) of the electric current for driving said electric motor (1) is set to a first frequency (fstart), and later to the operating frequency (frun) of the electric motor (1), wherein the first frequency (fstart) is higher than the operating frequency (frun).

Abstract: A motor is provided with stator windings arranged on a circumference of stator. Multiple-phase currents are supplied to the stator windings. A current is supplied to rotor windings. The multiple-phase currents include torque current components, which are arranged to be opposite in directions to torque current components of the current. By this mutually opposite-directional current arrangement, a sum of both torque current components results in a magnetomotive force of zero. It is also possible to reduce influence of the torque current components on the field magnetic fluxes of the motor. In the motor, circumferential magnetic flux components can be concentrated on an airgap and a portion near therearound, so that a larger amount of torque can be obtained, and constant output control can be performed more easily.

Abstract: A motor has stator windings arranged on a circumference of a stator, a rotor with rotor magnetic poles provided by N- and S-poles, and rotor windings arranged in a circumferential direction of the rotor magnetic poles. Multiple-phase currents are supplied to the stator windings. A current is supplied to rotor windings. The multiple-phase currents include torque current components, which are arranged to be opposite in directions to torque current components of the current. By this mutually opposite-directional current arrangement, a magnetomotive force based on a sum of both torque current components becomes a local minimum. It is possible to reduce influence of the torque current components on the field magnetic fluxes of the motor. In the motor, circumferential magnetic flux components can be collected to an airgap and a portion therearound, so that a larger amount of torque can be obtained, and constant output control can be performed more easily.

Abstract: The system and method for accurately determining range-to-go for the command detonation of a projectile. Using dual laser and/or radio frequency detectors on the tail and on the nose of a spinning projectile to determine the range-to-go, time-to-go, or lateral offset from the projectile to the target.

Abstract: A device and method for generating single/split or three phase AC voltages from a DC source with 1 to 2 times gain in output voltage without using any DC/DC boost or an output transformer. An isolation/multiplexer/mixer circuit successively charges multiple power modules, allowing each power module to generate output voltage(s) with desired magnitudes and phases, and allows independent outputs of each power converter modules to be reconnected to obtain up to two times the conventional possible output voltage. An isolation block eliminates the common mode noise problem. The gain in output voltage and isolation between the output converters eliminates the need of the front end DC/DC converter or an output transformer for most of the DC voltage sources, which improves cost, power density, efficiency and reliability of the inverter.

Abstract: A motor control unit that does not make an occurrence of a noisy sound and a vibration and does not give a steering discomfort by changing parameters of a current feedback control section even if an electric characteristic of the motor varies with a system-switching due to a failure occurrence, and to an electric power steering apparatus using the same and a vehicle. The motor control unit controls a motor having multi-system motor windings by means of a 3-phase current feedback system provided with a current control section through a motor driving circuit of each winding system, having a function that changes by switching parameters of the current control section corresponding to a driving system number of the multi-system motor windings.

Abstract: A method and a circuit arrangement are provided in which a mechanical load applied to the motor shaft or a load angle of the motor can be detected without sensors in a stepper motor. This is achieved substantially based on the fact that the load or the load angle creates a mutually induced voltage (back EMF) in the motor coils and the load or the load angle is detected by determining the phase shift of the motor voltage at at least one of the motor coil relative to the coil current at said motor coil connection, the phase shift being caused by the mutually induced voltage. A method and a circuit arrangement are also provided wherein the motor current of a stepper motor can be controlled according to load angle in such a way that the current consumption of the motor is relatively low.

Abstract: A system and method for exciting an electrical machine with instantaneous non-sinusoidal current waveforms is disclosed. The system includes an inverter that controls current flow and terminal voltages in an electrical machine. The controller is further programmed to receive feedback on an air gap magnetic field in the electrical machine generated by an initial sinusoidal current demand, generate a non-sinusoidal current demand based on received air gap magnetic field feedback, and input the non-sinusoidal current demand to the inverter, thereby causing the inverter to output a non-sinusoidal current.

Abstract: A method of determining a slip estimate associated with an induction motor through analysis of voltage and current signals. A fundamental frequency is calculated from a representation (e.g., complex representation) of the voltage signal, and a saliency frequency is calculated from a representation of the current signal. An estimation of slip quantity is calculated according to a slip estimation function that includes the saliency frequency, a saliency order, the fundamental frequency, a quantity of rotor slots, and a quantity of poles of the motor.

Abstract: This application describes a motor designed to operate as a reluctance machine at low speeds and as an induction machine at high speeds. The drive waveform is composed of one or more harmonics to be used to match the reluctance pattern of the stator-rotor, causing the rotor to rotate due to the reluctance effect, and one or more other harmonics to induce current in the rotor, causing the rotor to rotate due to the induction effect and the subsequent interaction of the stator and rotor magnetic fields. The two effects are generally not applied simultaneously.

Abstract: A signal transmission apparatus of a DC brushless motor for a ceiling fan is provided. The signal transmission apparatus comprises a transmitting line. The transmitting line is configured to transmit processed output signals of a plurality of electromagnetic sensors, in which usage of transmission lines is reduced. The output signals of the electromagnetic sensors represent the operation of the magnetic poles of the DC brushless motor.

Abstract: The present invention relates to electrically magnetized synchronous machine comprising an electrically magnetized rotor, and electrically supplied sator windings, whereby it further comprises non-linear means, optionally controllable, such as rectifying means in a series with three sator phase windings, whereby a rotor field winding is arranged to be fed from said non-linear means.

Abstract: Solving Means: A field coil current and a stator current are controlled by a controller. The stator current is controlled under vector control and is controlled so that the phase keeps an efficient motor zone. In a case of rated power generation, when the motor speed is low, the phase current and field coil current are increased to reserve the generated power. And, as the speed is increased, the phase current is decreased to reduce the copper loss, while in place of decreasing the phase current, the field coil current is kept high to reserve the generated power. Thereafter, as the speed is increased more, the field coil current is decreased to reduce the iron loss, while in place of decreasing the field coil current, the phase current is increased to reserve the generated power.

Abstract: A drive control apparatus, which controls an AC motor subjected to rotational drive by applying a rectangular wave voltage thereto, comprising: an actual torque detection section for detecting an actual torque value T outputted from the AC motor; an estimated torque calculation section for calculating an estimated torque value Tm based on a motor model with the AC motor in a simulated state; and a voltage phase calculation section wherein the voltage phase calculation section calculates a first voltage phase ?fb based on the actual torque value T and a command torque value T*, and a second voltage phase ?ff based on the estimated torque value Tm and the command torque value T* respectively, and outputs a value obtained by making the voltage phase subjected to weighting addition, as a voltage phase ?v.

Abstract: In the control of a synchronous motor having a permanent magnet, an alternating current power supply voltage that is input to a power amplifier or a direct current link voltage of which input voltage is rectified is measured. A reactive current (a d-axis current) or a current control phase advance is changed, according to this power supply voltage. With this arrangement, reactive current control or current phase control can be carried out directly according to a change in the input power supply voltage. A motor control device includes a voltage measuring unit that measures a voltage supplied to a driving amplifier, and a current control unit that controls a current passed to a synchronous motor based on the measured voltage. The voltage measuring unit measures a voltage supplied to the amplifier. The current control unit controls a current that is passed to the synchronous motor, according to the measured voltage.

Abstract: An excitation controller controls excitation of a synchronous machine, which is connected to a power transmission system through a transformer, so that a high-side voltage of the transformer is maintained at a target voltage with high accuracy. An output terminal target voltage of the synchronous machine is set to precisely compensate for a voltage drop in the transformer, corresponding to the transformer phase angle variation. To achieve this result, the excitation controller detects an output terminal voltage and an output current of the synchronous machine and calculates active and reactive currents of the output current, sets the output terminal target voltage of the synchronous machine from the active and reactive currents, the high-side voltage of the transformer, and the reactance of the transformer, and controls excitation of the synchronous machine to compensate for the voltage drop in the transformer corresponding to phase angle variation of the transformer.

Abstract: A speed control apparatus for a synchronous reluctance motor is disclosed. The speed control apparatus includes a voltage detector for detecting a voltage applied to the motor, a first phase converter for receiving voltages in three phases from the voltage detector and converting the three-phase voltages into equivalent voltages in two phases, a current detector for detecting a current applied to the motor, a second phase converter for receiving currents in three phases from the current detector and converting the three-phase currents into equivalent currents in two phases, and a rotor speed operator for receiving the two-phase voltages thereby computing a speed of a rotor included in the motor. A speed controller for receiving a deviation between a speed command externally inputted and an output value from the rotor speed operator is provided for generating a torque-related current command.

Abstract: A servo controller capable of controlling motors to be driven in different control modes, such as a synchronous motor and an induction motor, irrespectively of the type of the motor, and also capable of carrying out servo control by using incremental feedback signals. A control section common to individual motors and a control section dedicated to each motor are provided in a servo controller. The common control section is always used, while the dedicated control section is selectively used in accordance with the motor to be driven. Thereby, motors each requiring a different control mode can be controlled by the servo controller of one type. The use of th servo controller of one type can reduce maintenance management and a load on a CNC. Also, the provision of the control section common to individual motors can restrain increases of size, installation area and manufacturing cost of the device.

Abstract: The present invention provides a method for controlling an induction motor. The method comprises determining an input impedance of the motor at an operating point; determining an input electrical power to the motor at the operating point; and estimating a slip or shaft speed of the motor at the operating point from the input impedance and input electrical power.

Abstract: During the run-up of high-power synchronous machines (6), such as those used in pumped storage plants, in gas turbines sets and so forth, unwanted alternating currents with slip frequencies between those of the phase swings and the nominal frequency (50 Hz) of the synchronous machine (6) can also occur in the disturbed condition in addition to low-frequency plant-specific phase swings. These alternating currents are induced in the field windings of the synchronous machine (6) as a consequence of an unwanted asynchronous starting and can lead to inadmissible heating of the synchronous machine and to overvoltages in the field circuit. Alternating voltages (U1) associated with the slip frequencies are detected from use of a sensing resistor (4) in the exciter current (i.sub.

Abstract: A method of starting an AC motor from any initial speed using open loop control is provided. Sufficient current is provided to the motor so that motor flux can be developed. The frequency provided to the AC motor is varied and the stator frequency at which the motor peak flux occurs is determined. A transition to a control responsive to an external command at approximately the stator frequency at which the peak flux occurred is made.

Abstract: The disclosed inverter system comprises three three-phase inverters connected in parallel across a positive and a negative terminal of a DC source including a negative terminal, and two three-phase transformers each including star-connected primary windings connected at one end to three AC outputs of the mating inverter and at the other ends connected to the neutral source terminal. Three secondary windings of each transformer are serially connected to those of the other transformer across three star-connected phase windings of a synchronous motor and three AC output of that inverter not connected to the transformer. The motor includes a neutral terminal connected to the neutral source terminal.