Abstract: A direct-current power supply (40) is connected between the neutral points of two three-phase coils (24, 26) of a 2Y motor (22) constituted of the windings of the two three-phase coils (24, 26), which are connected in Y-connection and wound on a same stator, and to which three-phase alternating current power is severally supplied with a phase difference of a shifted angle between the windings from two inverter circuits (30, 32) having a positive pole bus (34) and a negative pole bus (36) for common use. A capacitor (38) is connected between the positive pole bus (34) and the negative pole bus (36). The electric potential difference between the neutral points of the three-phase coils (24, 26) is made larger or smaller than the voltage of the direct-current power supply (40) through the switching control of the inverter circuits (30, 32). Thereby, the capacitor (38) can be charged or discharged. Consequently, an inverter input voltage can be adjusted within a wide range.

Abstract: A direct-current power supply connecting the negative pole bus of an inverter circuit and the neutral point of a motor and a capacitor connecting the positive pole bus of the inverter circuit and the neutral point of the motor are provided for performing the switching control of the transistors T1-T6 of the inverter circuit on the basis of a phase voltage command value formed by the addition of a direct-current component and an alternating-current component. The voltage between the terminals of the capacitor is controlled on the direct-current component, and the driving control of the motor is performed on the alternating-current component. The supply voltage of the direct-current power supply can be made to be lower than a voltage necessary to drive the motor.

Abstract: To improve accuracy in controlling battery output, a charge-storage element is connected in parallel to a plurality of power source units. Each power source unit includes a power source element, and power transmission and reception between the power source element and a neutral point N side can be controlled by controlling the ratio of time over which an open/close switch remains closed, determined according to which among the voltage at the power source element or a voltage across the power source unit is larger or smaller. As an output of each power source element can be controlled, accuracy in output control for the combination battery can be improved.

Abstract: To improve accuracy in controlling battery output, a charge-storage element is connected in parallel to a plurality of power source units. Each power source unit includes a power source element, and power transmission and reception between the power source element and a neutral point N side can be controlled by controlling the ratio of time over which an open/close switch remains closed, determined according to which among the voltage at the power source element or a voltage across the power source unit is larger or smaller. As an output of each power source element can be controlled, accuracy in output control for the combination battery can be improved.

Abstract: When the absolute values of the negative voltage V− and the positive voltage V+ of a rectangular wave to be applied to the three phase coils of the motor driven using a rectangular-waved voltage are different, time T1 and time T2 for the rectangular wave are adjusted such that the area A representing the absolute value of a time integration value of the negative voltage V− and the area B representing the absolute value of a time integration value of the positive voltage V+ becomes equal to each other. With this adjustment, the average voltage of the rectangular wave becomes of value 0, so that a DC component current is prevented from flowing into the three phase coils of the motor.

Abstract: A synchronous motor control system which can freely regulate n-phase electric currents in a synchronous motor to control the characteristics of the synchronous motor. The synchronous motor control system can enhance the output torque per unit weight of a synchronous motor (40) simultaneously with reducing torque ripples. The waveform of three phase alternating currents is freely corrected over a range of +30 degrees from a specified electrical angle, at which a target phase current drawing a sine-wave curve reaches its peak value. It is assumed that this range of .+-.30 degrees corresponds to a range of 0 degree to 60 degrees. By way of example, the waveform is controlled to the peak value of the phase current in a range of 0 degree to 28 degrees. The correction of the phase current is carried out for the target phase which produces the primary magnetic flux of a revolving magnetic field.

Abstract: The present invention provides a magnets containing-type motor that minimizes a cogging torque without lowering its output. In a magnets containing-type motor where permanent magnets are set in magnetic pole elements of a rotor, the dimensions of each magnetic pole element are determined to satisfy predetermined relations according to a variety of numerical elements of the motor. In accordance with a concrete arrangement, the dimensions of each magnetic pole element are determined, so as to enable either one of a magnetic pole element opening angle L2 and an equivalent magnetic pole element opening angle L3 to be expressed as (n+z).multidot.Pp+x.multidot.(g/R)+y.multidot.(gp/R), based on a predetermined relation between a parameter (t2-t1)/g and a predetermined threshold value.

Abstract: A linear generator according to the present invention is adapted to generate a voltage proportional to the speed of a movable member or rotor and enable the movable member to be smoothly moved. The linear generator includes a first part having permanent magnets fixed to a yoke which are magnetized to the direction perpendicular to the longitudinal direction of a shaft, and a second part having a coil wound around the bobbins and a housing enclosing the coil. A plurality of magnetic poles are provided between the magnets and coils.

Abstract: An inverter current controlling method wherein output currents of an inverter having a plurality of switching elements and connected to a three-phase load are detected, and the switching elements are ON/OFF controlled so that the waveforms of the output currents are approximated to set output current wave commands, respectively, comprising: maintaining a specific switching element in a specific state so that a specific output terminal of the inverter is fixed to a specific polarity during a period of time when a specific ideal phase voltage of the three-phase load corresponding to the output current wave command is in a predetermined phase; and ON/OFF controlling the switching elements other than the specific switching element during the period of the predetermined phase so that the output current waveforms are approximated to the output current wave commands, respectively. Also disclosed is an inverter current controlling apparatus suitably employed in the above-mentioned method.