Abstract: An antenna device, which has wide-angle directivity and a configuration suitable to be used in a portable electronic apparatus, includes a flat board-like substantially rectangular soft magnetic body, and a loop-shaped coil disposed from a front surface to a rear surface of the soft magnetic body such that a region surrounded by the coil includes at least a part of a specific edge, i.e., one edge out of four edges of the soft magnetic body, and does not include a facing edge that faces the specific edge.

Abstract: It is composed of a three-phase three-level inverter 1, three single-phase five-level inverters 2, each of which is connected in series with an output of each phase of the three-phase three-level inverter 1, and pulse width modulation control means 8 provided for each phase which supplies gate pulses to the three-level inverter 1 and the single-phase five-level inverter 2 of the relevant phase.

Abstract: In a motor driving system, a motor driving system is provided which simplifies the system by ceasing ON/OFF control of a commercial driving command, and by performing commercial synchronous transfer and capture control based on a drive speed reference. A system controller performs synchronization control so as to make a drive output coincident with a phase/amplitude of a commercial AC power source when a rotation speed of a motor exceeds a drive speed reference n2, and when a prescribed requirement is satisfied, the commercial AC power source is synchronously transferred, and the motor is driven by the commercial AC power source. In addition, when the drive speed reference is set to n1, and a drive output side switch is closed, the drive output is connected to the commercial AC power source, and when a prescribed requirement is satisfied, the motor is started to be driven at a variable speed (t7), and thereby the synchronous capture is performed.

Abstract: An inverter test apparatus includes a DC power supply, a second inverter which is connected to a DC side of the first inverter, an inductor which is connected between an AC side of the first inverter and an AC side of the second inverter, a first controller which controls an AC voltage of the first inverter to be at a constant amplitude and a constant frequency, a current detector which detects a current that flows through the inductor, a phase command value computation module which computes a phase command value of the second inverter so as to control the current detected by the current detector, and a second controller which controls a phase of the second inverter, based on the phase command value computed.

Abstract: It is composed of a three-phase three-level inverter 1, three single-phase five-level inverters 2, each of which is connected in series with an output of each phase of the three-phase three-level inverter 1, and pulse width modulation control means 8 provided for each phase which supplies gate pulses to the three-level inverter 1 and the single-phase five-level inverter 2 of the relevant phase.

Abstract: A drive system for driving a multi-phase motor (such as a three-phase AC motor) or other load. Where a transformer is used, the transformer may have a disconnected wye configuration on the secondary side. The system may also utilize the average or other combination of DC bus voltages of inverters for each load phase, to provide feedback control.

Abstract: An antenna device, which has wide-angle directivity and a configuration suitable to be used in a portable electronic apparatus, includes a flat board-like substantially rectangular soft magnetic body, and a loop-shaped coil disposed from a front surface to a rear surface of the soft magnetic body such that a region surrounded by the coil includes at least a part of a specific edge, i.e., one edge out of four edges of the soft magnetic body, and does not include a facing edge that faces the specific edge.

Abstract: Systems and methods are shown for detecting a blown fuse in a three-phase line by comparing neutral points in the line before and after the fuses. Diode rectifier circuits may be used to compare the neutral points and generate a DC output voltage when neutral points are off from one another, and photocoupler circuits may provide electrical isolation when signaling a neutral point shift. The neutral points compared need not be on immediate sides of the fuses, so intermediate components may exist, and in some embodiments one of the compared points may be within a load connected to the three-phase line.

Abstract: An inverter system for driving electrical loads such as multi-phase induction motors is disclosed utilizing five single-phase inverter cells configured in a wye configuration. Inverter cells such as neutral-point-clamp inverter cells are configured to generate a voltage waveform between two output terminals and further configured with a terminal providing a neutral voltage reference point with respect to each of the two output terminals. The inverter cells may be configured with the neutral voltage reference points connected together and with one output terminal from each inverter cells connected together to provide three outputs of the inverter system at different voltage phases and with the common neutral reference point as the wye connection of the three outputs. The other three single phase inverter cells may be added to each of the three outputs to boost the output voltage of the inverter system and decrease the maximum voltage requirements on each inverter cell.

Abstract: A drive system for driving a multi-phase motor (such as a three-phase AC motor) or other load. Where a transformer is used, the transformer may have a disconnected wye configuration on the secondary side. The system may also utilize the average or other combination of DC bus voltages of inverters for each load phase, to provide feedback control.

Abstract: A system for transmitting electric power from an electric power transmission apparatus (10) to an electric power reception apparatus (50) by using electromagnetic induction between a power receiving coil (60) and a power transmitting coil (40). The electric power transmission apparatus (10) comprises an electric power switching circuit (14), a first capacitor (20) and an electric power derivation circuit (30). The electric power switching circuit (14) includes a switching element (16) and an output point (P) and switches the switching element (16) at a predetermined switching frequency (f), thereby causing the electrical potential at the output point (P) to exhibit a predetermined variation, wherein the predetermined variation is an electrical potential variation obtainable by the half-wave rectification of a sinusoidal wave variation which has a predetermined amplitude. The first capacitor (20) is coupled between the output point (P) and a first constant electrical potential (ground).

Abstract: Systems and methods are shown for detecting a blown fuse in a three-phase line by comparing neutral points in the line before and after the fuses. Diode rectifier circuits may be used to compare the neutral points and generate a DC output voltage when neutral points are off from one another, and photocoupler circuits may provide electrical isolation when signaling a neutral point shift. The neutral points compared need not be on immediate sides of the fuses, so intermediate components may exist, and in some embodiments one of the compared points may be within a load connected to the three-phase line.

Abstract: An inverter system for driving electrical loads such as multi-phase induction motors is disclosed utilizing five single-phase inverter cells configured in a wye configuration. Inverter cells such as neutral-point-clamp inverter cells are configured to generate a voltage waveform between two output terminals and further configured with a terminal providing a neutral voltage reference point with respect to each of the two output terminals. The inverter cells may be configured with the neutral voltage reference points connected together and with one output terminal from each inverter cells connected together to provide three outputs of the inverter system at different voltage phases and with the common neutral reference point as the wye connection of the three outputs. The other three single phase inverter cells may be added to each of the three outputs to boost the output voltage of the inverter system and decrease the maximum voltage requirements on each inverter cell.

Abstract: On the basis of rainfall amount data (24) representing a timeseries change in the amount of rainfall in a district as an estimation target and unascertained water amount data (23) representing a time-series change in the amount of unascertained water at a base point located downstream of each district, an unascertained water occurrence distribution estimating unit (12) of a control unit (10) calculates a correlation value between the rainfall amount data (24) in each district and the unascertained water amount data (23), and outputs each correlation value as an unascertained water occurrence distribution in each district.

Abstract: A multi-level power converter is disclosed. The converter includes a DC power source having N (N is an Integer more than two)-level voltage potentials, and a plurality of switching legs connected in parallel to the DC power source. The switching leg has switching elements in series connection, and clamp diodes connected between intermediate DC potential terminals to middle points of the switching legs. The converter is provided with a control means for supplying gate pulses to the switching elements, and a supervising means for supervising every switching element to output a failure signal. The converter further includes a logic operating means for detecting an over-current failure of main circuit elements to output a device fault signal using the failure signals An operation of the logic operating means at least includes AND condition of at least two failure signals to output the device fault signal.

Abstract: A case base (54) is generated from historical data containing inflow data (31) that indicates a sewage inflow measured at a sewage treatment plant (10) and meteorological data (33) corresponding to the inflow data (31). A similar case search section (56) and output estimation section (57) predict a sewage inflow corresponding to an input prediction condition (40) after a predetermined prediction time in real time using the case base (54) and output inflow prediction data (20).

Abstract: In a power inverter system, an inverter unit includes first to third single-phase inverters. In the power inverter system, a reference-frequency calculating unit calculates a reference frequency of each of the first to third single-phase inverters. A reference-voltage-calculating unit calculates a reference voltage of each of the single-phase inverters. In the power inverter system, a voltage-correcting unit adds a correction voltage to the reference voltage calculated by the reference voltage-calculating unit. The correction voltage has a frequency three times as high as the reference frequency.

Abstract: A multi-level power converter is disclosed. The converter includes a DC power source having N (N is an Integer more than two)-level voltage potentials, and a plurality of switching legs connected in parallel to the DC power source. The switching leg has switching elements in series connection, and clamp diodes connected between intermediate DC potential terminals to middle points of the switching legs. The converter is provided with a control means for supplying gate pulses to the switching elements, and a supervising means for supervising every switching element to output a failure signal. The converter further includes a logic operating means for detecting an over-current failure of main circuit elements to output a device fault signal using the failure signals An operation of the logic operating means at least includes AND condition of at least two failure signals to output the device fault signal.

Abstract: On the basis of rainfall amount data (24) representing a time-series change in the amount of rainfall in a district as an estimation target and unascertained water amount data (23) representing a time-series change in the amount of unascertained water at a base point located downstream of each district, an unascertained water occurrence distribution estimating means (12) of a control unit (10) calculates a correlation value between the rainfall amount data (24) in each district and the unascertained water amount data (23), and outputs each correlation value as an unascertained water occurrence distribution in each district.

Abstract: In a power inverter system, an inverter unit includes first to third single-phase inverters. In the power inverter system, a reference-frequency calculating unit calculates a reference frequency of each of the first to third single-phase inverters. A reference-voltage-calculating unit calculates a reference voltage of each of the single-phase inverters. In the power inverter system, a voltage-correcting unit adds a correction voltage to the reference voltage calculated by the reference voltage-calculating unit. The correction voltage has a frequency three times as high as the reference frequency.