Abstract: Under a condition that a command to stop a fuel cell system is received and a state of charge of a secondary battery is equal to or lower than a threshold which is a value obtained by adding a first predetermined value to a lower limit at which electric power required to stop and start the fuel cell system is supplied, forced charging of the secondary battery by a fuel cell is performed until the state of charge reaches the threshold. After the forced charging is performed, in a case where the command to stop the fuel cell system is received within a predetermined period, the controller sets the threshold to a value obtained by adding a second predetermined value lower than the first predetermined value to the lower limit under the condition.

Abstract: A fuel cell system including: a fuel cell; a voltage sensor that measures output voltage of the fuel cell; a converter that boosts the output voltage; and a control unit that controls the converter using a duty ratio including a feedforward term and a feedback term, the feedforward term being set to perform feedforward control, the feedback term being set to perform feedback control, wherein when the control unit causes the converter to boost the output voltage, and when the feedforward term calculated by specified Expression I exceeds an upper limit calculated by specified Expression II, the control unit causes the converter to boost the voltage output from the fuel cell with the duty ratio including the upper limit and the feedback term.

Abstract: A fuel cell system for a vehicle includes: a fuel cell; a plurality of loads that consumes power generated by the fuel cell and includes a vehicle driving motor; a secondary battery configured to be charged with excess power when an amount of power generated by the fuel cell is greater than an amount of power consumed by the loads and to discharge shortage power when the amount of power generated by the fuel cell is less than the amount of power consumed by the loads; and a control unit configured to control the amount of power generated by the fuel cell such that an amount of charging-discharging power of the secondary battery is maintained at a predetermined value.

Abstract: Provided is a voltage control device of a fuel-cell vehicle capable of securing good acceleration responsiveness while suppressing battery deterioration even when a vehicle acceleration request is made in the situation where the output from a battery is restricted. When determining that electric power suppliable from a secondary battery to an air compressor is less than a lower limit of an acceleration maintaining-electric power of the air compressor, a voltage control device of a fuel-cell vehicle maintains a state where electric power generated by a fuel cell is consumed by an electric power drive, and supplies the electric power consumed by the electric power drive to the air compressor when a vehicle acceleration request is made.

Abstract: A fuel cell system includes: a fuel cell stack; a voltage sensor configured to detect voltage of the fuel cell stack; a fuel cell relay connected to the fuel cell stack; a switch connected between the fuel cell stack and the fuel cell relay; an overcurrent detector configured to detect an overcurrent flowing to the switch; and a power generation stop device configured to stop power generation of the fuel cell stack when the overcurrent detector detects the overcurrent and the detected voltage becomes a specified value or less.

Abstract: There is provided a fuel cell system. This fuel cell system comprises a fuel cell configured to generate electric power using reactive gases; a voltage sensor configured to measure a voltage output from the fuel cell; a converter configured to boost an input voltage that is input from the fuel cell; and a controller configured to control the converter. In the case where the voltage output from the fuel cell to the converter is to be boosted after a changeover of an operating state of the fuel cell system from an intermittent operation to an ordinary operation, when a duty ratio D1 calculated by Mathematical Formula I is greater than a duty ratio D2 calculated by Mathematical Formula II, the controller causes the converter to boost the voltage output from the fuel cell at the duty ratio D2. [ Math .

Abstract: A fuel cell system includes a drive motor, a fuel cell, an auxiliary machine, a secondary battery, a temperature sensor, a current sensor, and a control section. The control section controls the secondary battery for discharging by driving the drive motor or the auxiliary machine and for charging through power generation by the fuel cell or regeneration by the drive motor when a temperature measured by the temperature sensor is lower than a specified value.

Abstract: An object of the present invention is to reduce the period of time required to stop a fuel cell system and to suppress freezing of a fuel cell. The fuel cell system includes a controller that controls operations of a fuel cell, and the controller operates the fuel cell in a dry condition according to a state quantity (e.g., impedance) of the fuel cell in operation. The controller can operate the fuel cell in a dry condition before a system stop command is issued. In addition, the controller can switch an operation of the fuel cell from a dry condition to a wet condition when a required output of the fuel cell or a vehicle speed of a vehicle equals or exceeds a predetermined value.

Abstract: Even in a fuel cell system which performs scavenging processing after the power generation of a fuel cell is stopped, the operation time for when a battery is being operated can be increased. When determining that the condition of running out of gas occurs based on a sensor value of a pressure sensor, a control unit stops the power generation of the fuel cell. The control unit, for example, shortens the time required for scavenging processing and then performs the scavenging processing. On the other hand, when determining that the condition of running out of gas does not occur and when the power generation of the fuel cell should be stopped, the control unit stops the power generation and then performs normal scavenging processing.

Abstract: An LED driving apparatus comprises a power supply unit that includes a transformer having a primary coil and a plurality of secondary coils and outputs alternating power from the plurality of secondary coils; a current balancing unit and a first rectification smoothing unit connected to a first secondary coil of the plurality of secondary coils; an LED load group that includes a plurality of LEDs connected in series and to which power smoothed from the first rectification smoothing unit is supplied; a power control unit that controls power to be supplied to the first and second LED loads, based on currents flowing in the first and second LED loads; and a direct current load that is connected to both ends of a second secondary coil of the plurality of secondary coils. The power supplying unit controls the alternating power, based on the power supplied to the direct current load.

Abstract: A fuel cell system has a flooding elimination mode as one of available operation modes of fuel cells and includes a drive controller. When the ambient temperature of the fuel cell system is not higher than a preset first temperature, the drive controller causes the fuel cells to be driven in the flooding elimination mode. When the ambient temperature of the fuel cell system is not lower than a preset second temperature that is higher than the first temperature, the drive controller prohibits the fuel cells from being driven in the flooding elimination mode. On the occasion of input of a checkup instruction of the fuel cells, the drive controller causes the fuel cells to be driven in the flooding elimination mode, independently of the ambient temperature. This arrangement effectively improves the user's convenience at the checkup time of the fuel cell system having the operation mode for eliminating the state of flooding.

Abstract: A resonant converter includes: a first switching element and a second switching element, which are connected in series; a series resonant circuit, which includes a primary coil of a transformer having leakage inductance and a current resonant capacitor, and which is connected in parallel to one of the first switching element and the second switching element; a rectifying-and-smoothing circuit, which is connected to a secondary coil of the transformer, wherein an output voltage is to be supplied to a load; and a clamp circuit, which clamps a voltage between both ends of the current resonant capacitor to a predetermined voltage value, wherein, when an output current supplied from the rectifying-and-smoothing circuit to the load is higher than the predetermined current value, an output characteristic is set so that, as the output current is increased, the output voltage is decreased.

Abstract: The present invention includes: a power factor correction circuit configured to correct a power factor; a DC/DC converter configured to convert an output voltage of the power factor correction circuit to a different direct-current voltage; an input voltage detector configured to detect an input voltage inputted into the power factor correction circuit; and a power factor correction circuit output voltage controller configured to generate a voltage instruction for controlling the output voltage of the power factor correction circuit, based on a value of the detected input voltage, an output current value to a load connected to an output of the DC/DC converter or an output power value of the load, as well as a set value of an input voltage short break output hold time, and to output the voltage instruction to the power factor correction circuit.

Abstract: A DC converter includes: a transformer (T1) including a primary winding (P1) and a secondary winding (S1); a series resonant circuit in which a current resonant reactor (Lr), the primary winding (P1) of the transformer, and a current resonant capacitor (Cri) are connected in series; conversion circuits (Q1, Q2) for converting a DC voltage of a DC power supply (Vin) into a rectangular-wave voltage, so as to output the rectangular-wave voltage to the series resonant circuit; and a rectifier smoothing circuit (D3, D4, Co) for rectifying and smoothing a voltage generated at the secondary winding (S1) of the transformer, so as to output a DC output voltage to a load, wherein a capacitive element (Cr) including a capacitive component corresponding to a floating capacitance (Cp) equivalently present between the primary winding of the transformer was connected to the current resonant reactor (Lr) in parallel.

Abstract: A DC conversion apparatus comprises a first transformer, a second transformer, a parallel circuit having series circuits connected in parallel, one of the series circuits including a reactor and a primary winding of the first transformer, the other series circuit including a reactor and a primary winding of the second transformer, a conversion circuit converting a DC voltage of a DC power source into an AC voltage and outputting it to the parallel circuit, a first rectifying-smoothing circuit rectifying and smoothing a first voltage generated by a first secondary windings of the first transformer into a first DC output, and a second rectifying-smoothing circuit rectifying and smoothing a second voltage generated by a first secondary windings of the second transformer into a second DC output that is different from the first voltage. The second secondary windings of the first transformer are connected in parallel with the first secondary windings of the second transformer.

Abstract: A fuel cell system capable of adequately controlling the water content of a fuel cell is provided. An impedance reference value is stored in a memory for an impedance comparator. The impedance reference value is a reference value that is set in order to prevent the water content in a fuel cell from decreasing too much. The impedance comparator compares a measured impedance value supplied from an impedance operation unit with the impedance reference value and performs scavenging control based on the comparison result.

Abstract: A current balancing apparatus includes a first transformer having a first primary winding and a first secondary winding electromagnetically coupled with the first primary winding, the first primary winding having a first end connected to a first load that passes a first current; a second transformer having a second primary winding and a second secondary winding electromagnetically coupled with the second primary winding, the second primary winding having a first end connected to a second load that passes a second current having an AC component substantially having a 180-degree phase difference with respect to the first current; and a series circuit including the first secondary winding, the second secondary winding, and a current smoother, to balance the first current and second current with each other.

Abstract: The present invention seeks, when a temporary abnormality occurs in a voltage converter, a recovery of the voltage converter, and minimizes the inadequacy of the drive power. In a fuel cell system comprising an electric storage device disposed with a voltage converter, in the case where an abnormality occurs in the voltage converter, the voltage converter is stopped once, an attempt is made to recover the voltage converter to a normal state after the voltage converter is stopped, and drive power is generated in at least a fuel cell until the voltage converter recovers to the normal state. It is preferred that an upper limit of the power which can be generated when the voltage converter recovers to the normal state be set to a value lower than an upper limit of power obtained prior to the occurrence of the abnormality. Further, it is preferred that the limit be canceled step by step when recovering the voltage converter to a normal state.

Abstract: A fuel cell system that can continue a stable operation of a fuel cell and perform un-interrupted operation of the system even upon the occurrence of an abnormality in a voltage converter, and a mobile body. A fuel cell system where an accumulator device is connected to a load via a voltage converter in parallel with a fuel cell includes an auxiliary equipment connected nearer the fuel cell than the voltage converter, and a control device for controlling the voltage converter and the auxiliary equipment. The control device changes the operational point of the auxiliary equipment when an abnormality has occurred in the voltage converter.

Abstract: An LED driving apparatus comprises a power supply unit that includes a transformer having a primary coil and a plurality of secondary coils and outputs alternating power from the plurality of secondary coils; a current balancing unit and a first rectification smoothing unit connected to a first secondary coil of the plurality of secondary coils; an LED load group that includes a plurality of LEDs connected in series and to which power smoothed from the first rectification smoothing unit is supplied; a power control unit that controls power to be supplied to the first and second LED loads, based on currents flowing in the first and second LED loads; and a direct current load that is connected to both ends of a second secondary coil of the plurality of secondary coils. The power supplying unit controls the alternating power, based on the power supplied to the direct current load.