Abstract: A controller switches between modes each having a different connection state of a DC power supply and the capacitor with respect to first and second output points by controlling switches. A generation unit generates a reference wave including at least one carrier wave. The modes are classified into a sustaining mode in which no current is caused to flow to the capacitor, a charging mode in which a current is caused to flow to the capacitor, and a discharging mode in which a current in a direction opposite to that in the charging mode is caused to flow to the capacitor. The controller switches between the sustaining mode and a charging or discharging mode according to the comparison result between a signal wave and the reference wave.

Abstract: A power converter 1 includes a first conversion circuit 10 connected with a first winding n1 of a transformer 40, and a second conversion circuit 20 connected with a second winding n2 of the transformer 40. The first and second conversion circuits 10 and 20 are configured to perform bidirectional power conversion. The power converter further includes a third conversion circuit 30 that is a circuit provided at a pre-stage of the first conversion circuit 10 in a direction of transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10. The third conversion circuit 30 is configured to perform bidirectional power conversion, and function as a boosting chopper circuit upon transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10.

Abstract: A first conversion circuit is electrically connected between a reference potential point and a first input point on a high potential side of a direct current power supply. A second conversion circuit is electrically connected between the reference potential point and a second input point on a low potential side of the direct current power supply. A voltage-regulating circuit is configured to adjust a magnitude of an applied voltage to the first conversion circuit and the second conversion circuit. The voltage-regulating circuit is configured to increase the magnitude of the applied voltage over time during a start time period from a start of supplying power from the direct current power supply until a first capacitor and a second capacitor are charged to a specified voltage.

Abstract: A first conversion circuit switches a magnitude of a voltage generated between a first output point and a reference potential point in three stages. The second conversion circuit switches a magnitude of a voltage generated between the reference potential point and a second output point in three stages. The third conversion circuit includes first to fourth switches in a full bridge configuration and converts a voltage generated between the first output point and the second output point into an alternate current voltage and outputs the alternate current voltage. The third conversion circuit forms a current path including inductors between the first output point and the second output point during a start time period from a start of supplying power from a direct current power supply until a first capacitor and a second capacitor are charged to a specified voltage.

Abstract: In a discharging operation of a vehicle storage battery, a controller switches between a full-wave rectification operation of full-wave rectify a voltage across a second winding while maintaining a second short circuit in an open state, and a full-wave voltage doubling rectification operation of full-wave voltage doubling rectify a voltage across second winding while maintaining second short circuit in a closed state, based on magnitude relationship between DC voltage across first terminals and DC voltage across second terminals.

Abstract: Connector for electrical connection includes coupler, cable, switch mechanism, failure detector and transmitter. Coupler is removably inserted in and connected to reception side connector provided in machine which is equipped with storage battery. Cable includes two or more electric wires including power line configured to be electrically connected to reception side connector via coupler. Cable is connected to device that performs at least one of supplying power to machine and receiving power from machine. Switch mechanism opens and closes electrical circuit between coupler and power line. Failure detector detects occurrence of failure of coupler. Transmitter transmits detection result of failure detector to device through at least one first electric wire of the two or more electric wires. Switch mechanism opens and closes the electrical circuit in accordance with control signal transmitted through first electric wire.

Abstract: A first bidirectional switch is electrically connected between a first connection point which is a connection point of a first switching element and a second switching element and a second connection point which is a connection point of a seventh switching element and an eighth switching element. A second bidirectional switch is electrically connected between a third connection point which is a connection point of a third switching element and a fourth switching element and a fourth connection point which is a connection point of a fifth switching element and a sixth switching element. A power-converting device is configured to generate an output voltage between a first output point and a second output point.

Abstract: There is provided a device including: an inverter 5 including switching elements 51-52 for outputting a U-phase voltage and switching elements 53-54 for outputting a W-phase voltage; midpoint capacitors 31-32; a midpoint stabilizer 2 configured to regulate a power storage amount of each of the midpoint capacitor 31 and the midpoint capacitor 32; and a controller 7 configured to control the switching elements 51-54 so as to supply a desired U-phase voltage and a desired W-phase voltage based on voltages between the U-phase voltage line and the neutral line and the voltage between the W-phase voltage line and the neutral line, and control the midpoint stabilizer 2 so as to adjust the midpoint potential in the O phase based on the condition of the midpoint potential in an O phase at a connecting point between the midpoint capacitor 31 and the midpoint capacitor 32.

Abstract: An inverter device (1), including a first inverter (10), and a second inverter (20) connected in parallel to the first inverter. Both the first and second inverters (10, 20) are three-level inverters. The first and second inverters (10, 20) generate first and second output voltages (V1, V2) using the voltage (Vc) at the connection point between a first capacitor (C1) and a second capacitor (C2) connected in series and evenly allocating a power supply voltage (Vin). A control circuit (40) duty-controls the second inverter at high frequency, when the second inverter (20) switches the level of the second output voltage (V2).

Abstract: A power converter 1 includes a first conversion circuit 10 connected with a first winding n1 of a transformer 40, and a second conversion circuit 20 connected with a second winding n2 of the transformer 40. The first and second conversion circuits 10 and 20 are configured to perform bidirectional power conversion. The power converter further includes a third conversion circuit 30 that is a circuit provided at a pre-stage of the first conversion circuit 10 in a direction of transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10. The third conversion circuit 30 is configured to perform bidirectional power conversion, and function as a boosting chopper circuit upon transferring electric power toward the second conversion circuit 20 from the first conversion circuit 10.

Abstract: In a discharging operation of a vehicle storage battery, a controller switches between a full-wave rectification operation of full-wave rectify a voltage across a second winding while maintaining a second short circuit in an open state, and a full-wave voltage doubling rectification operation of full-wave voltage doubling rectify a voltage across second winding while maintaining second short circuit in a closed state, based on magnitude relationship between DC voltage across first terminals and DC voltage across second terminals.

Abstract: A power conditioner includes first and second power conversion portions, a smoothing capacitor, and an auxiliary power supply. The first power conversion portion is connected to a DC system. The second power conversion portion is connected to an AC system. The capacitor is connected between wires of an intermediate bus which connects input/output terminals of the first power conversion portion and the second power conversion portion. The auxiliary power supply receives commercial power and generates an auxiliary charge voltage to be applied to the capacitor. The first power conversion portion converts DC power of the storage battery to a first DC voltage and outputs the first DC voltage to the intermediate bus. The second power conversion portion converts a voltage of the capacitor to an AC voltage and outputs the AC voltage to the AC system. The auxiliary charge voltage is lower than the first DC voltage.

Abstract: A power conversion system includes a power conversion device, a connector, and a processing module. The power conversion device is connected to a power system. The attached state and the unattached state of the connector relative to a connecting port that is provided in an apparatus having a battery mounted therein can be selected. The processing module is configured to determine that a malfunction has occurred when a voltage is applied to a portion that electrically connects the connector and the connecting port in a period in which transmission of electric power with respect to the battery is stopped.

Abstract: Connector for electrical connection includes coupler, cable, switch mechanism, failure detector and transmitter. Coupler is removably inserted in and connected to reception side connector provided in machine which is equipped with storage battery. Cable includes two or more electric wires including power line configured to be electrically connected to reception side connector via coupler. Cable is connected to device that performs at least one of supplying power to machine and receiving power from machine. Switch mechanism opens and closes electrical circuit between coupler and power line. Failure detector detects occurrence of failure of coupler. Transmitter transmits detection result of failure detector to device through at least one first electric wire of the two or more electric wires. Switch mechanism opens and closes the electrical circuit in accordance with control signal transmitted through first electric wire.

Abstract: A DC power supply system includes a DC power supply and a secondary battery for backing up the DC power supply. When a voltage of the DC power supply is lower than a voltage of the secondary battery, the DC power system adds an extra voltage to the voltage of the DC power supply to provide an input voltage to the secondary battery higher than the voltage of the secondary battery by using an electric power of the secondary battery, and the secondary battery is charged.

Abstract: An electric power supply apparatus, which enables a driving frequency of a switching circuit connected to a primary side of a transformer constant and output of a secondary side variable, comprises a transformer (5), a series circuit of two first switching elements (Q1, Q2) connected between terminals of a direct current power supply (2), an LC resonant circuit connected between both ends of one of the first switch element (Q2) and a primary winding (Np) of the transformer (5), bidirectional switch elements (Q3, Q4) connected to secondary windings (Ns1, Ns2) of the transformer (5) and having a rectification function and a phase control function, and a control circuit for inputting gate driving signals having a phase difference into the first switch elements (Q1, Q2) and the second switch elements (Q3, Q4).

Abstract: A DC/DC converter has DC input terminals to which a DC power is inputted, a transformer, and a bidirectional switching device on the primary side of the transformer.

Abstract: A solar power generation system includes: a solar power generation module 4; a power converter 3 for solar power generation configured to convert DC power generated by the solar power generation module 4 into AC power; a storage battery unit 2; a charge and discharge controller 1 configured to take out the AC power obtained through conversion by the power converter 3 for solar power generation from an isolated operation mode terminal 3a, and to store the AC power in the storage battery unit 2. A controller 16 detects input power taken out from the isolated operation mode terminal 3a and inputted into the charge and discharge controller 1, acquires generated power generated by the solar power generation module 4, and lowers the input power inputted into the charge and discharge controller 1 when a differential between the acquired generated power and the detected input power is not greater than a predetermined value.

Abstract: There is provided a device including: an inverter 5 including switching elements 51 52 for outputting a U-phase voltage and switching elements 53 54 for outputting a W-phase voltage; midpoint capacitors 31 32; a midpoint stabilizer 2 configured to regulate a power storage amount of each of the midpoint capacitor 31 and the midpoint capacitor 32; and a controller 7 configured to control the switching elements 51, 54 so as to supply a desired U-phase voltage and a desired W-phase voltage based on voltages between the U-phase voltage line and the neutral line and the voltage between the W-phase voltage line and the neutral line, and control the midpoint stabilizer 2 so as to adjust the midpoint potential in the O phase based on the condition of the midpoint potential in an O phase at a connecting point between the midpoint capacitor 31 and the midpoint capacitor 32.

Abstract: A multilevel inverter device comprises: a series circuit of a first switching element 21 and a second switching element 22 connected between a terminal at a high voltage side and a terminal at a low voltage side of a DC electric power supply 2; a series circuit of two capacitors 11 and 12, which is connected in parallel with the first switching element 21 and the second switching element 22, to generate an intermediate voltage of the DC electric power supply 2; and a single bidirectional switching element 100 connected between a connection point P1 of the two capacitors 11 and 12 and a connection point P2 of the first switching element 21 and the second switching element 22; and wherein the bidirectional switching element 100 has a horizontal transistor structure using GaN/AlGaN.