Abstract: A power supply control apparatus includes a switching control device configured to switch each of switching elements of a power converter between an on state and an off state alternately, and a discharge control device configured to, when residual charge of the fuel cell is discharged, control a gas supply unit such that oxidant gas is not supplied to the fuel cell, in a first period, control the switching control device such that an on time during which at least one switching element is maintained in the on state is longer than the on time during an operation of the fuel cell and the at least one switching element is switched between the on state and the off state alternately, and, in a second period subsequent to the first period, control the switching control device such that the at least one switching element continues to maintain the on state.

Abstract: A fuel cell stack includes: a first stack including: first unit cells stacked; and a first outer peripheral surface around a first stacking direction of the first unit cells; a second stack that is juxtaposed to the first stack including; second unit cells stacked along the first stacking direction of the first unit cells; and a second outer peripheral surface around a second stacking direction of the second unit cells; an external gas manifold that supplies and discharges a reactant gas to and from the first and second stacks; and an external coolant manifold that supplies and discharges a coolant to and from the first and second stacks.

Abstract: A fuel cell stack includes: a first stack including: first unit cells stacked; and a first outer peripheral surface around a first stacking direction of the first unit cells; a second stack that is juxtaposed to the first stack including; second unit cells stacked along the first stacking direction of the first unit cells; and a second outer peripheral surface around a second stacking direction of the second unit cells; an external gas manifold that supplies and discharges a reactant gas to and from the first and second stacks; and an external coolant manifold that supplies and discharges a coolant to and from the first and second stacks.

Abstract: A fuel cell system that includes a fuel cell and a secondary battery, each acting as a power supply source. A first converter a second converter is provided between the fuel cell and the secondary battery and first and second loads. A first inverter is provided between the first and second converters and the first load and a second inverter is provided between the first and second converters and the second load. A first controller controls an output of the fuel cell by controlling the first converter, and a second controller is configured separately from the first controller. If one of the first controller and the second controller receives the failure information sent from the other, the first controller or the second controller that has received the failure information stops operation of the control target thereof.

Abstract: In a fuel cell system which includes a high-electricity multiple-phase converter, noise generated due to an increase in reactor vibrations and due to a sound pressure increase caused by a plurality of reactors is effectively inhibited, and silence is improved. A fuel cell system includes a multiple-phase converter provided between a fuel cell and a load device. The fuel cell system includes: selecting means (e.g., a controller) for selecting a driving phase of the multiple-phase converter in accordance with the load of the load device; and driving means (e.g., a controller) for driving a plurality of driving phases, when selected by the selecting means, at carrier frequencies so that these driving phases are nearly opposite to each other.

Abstract: A fuel cell system includes; a fuel cell which generates electricity by using a fuel gas and an oxidant gas as reaction gases; current control means which controls current of a fuel cell; voltage control means which controls voltage of the fuel cell; and heat value control means which calculates a heat value required by the fuel cell system and decides a target current value of the current control means and a target voltage value of the voltage control means so as to generate the calculated necessary heat amount, thereby controlling the heat value. Thus, it is possible to supply a heat required for the fuel cell system without increasing the size of the fuel cell system.

Abstract: The step-up converter includes the plurality of converting units, each having the reactor and the semiconductor element part having electronic parts such as the transistor and the diodes. The ECU performs changeover control of increase or decrease of the number of drive phases of the converting units, based on the output condition from the fuel cell, the temperature condition of the reactor, and the temperature condition of the semiconductor element part.

Abstract: A fuel cell system capable of improving the voltage controllability of a converter provided in the system is provided. A controller judges whether or not a passing power of a DC/DC converter falls within a reduced response performance area for the number of active phases as of the present moment. When the controller determines that the passing power of the DC/DC converter falls within the reduced response performance area, the controller determines the number of phases which avoids the driving within the reduced response performance area, and outputs a command for switching to the determined number of phases (phase switching command) to the DC/DC converter.

Abstract: Provided is a fuel cell system capable of supplying electric power to external loads without excess or deficiency even when switching occurs between operation states. A warm-up timing judgment part judges whether it is time to operate warm-up based on the temperature of a fuel cell stack. A target shift voltage determination part determines a target output voltage of the fuel cell stack used during a warm-up operation, and a voltage change speed determination part determines a voltage change speed based on electric power required from the fuel cell stack, the target output voltage of the fuel cell stack used during the warm-up operation which is output from the target shift voltage determination part and a current output voltage detected by a voltage sensor. A voltage decrease execution part operates voltage decrease processing according to the voltage change speed indicated by the voltage change speed determination part.

Abstract: A fuel cell system capable of carrying out a proper current limiting even when decreasing a cell voltage through, e.g., a rapid warm-up is provided. When a rapid warm-up is started, an acceptable cell-voltage value setting part sets a acceptable lowest-cell-voltage value in accordance with the operation state of a fuel cell. Meanwhile, a target cell-voltage value setting part sets an initial value for a target lowest-cell-voltage value. The target cell-voltage value setting part then compares a lowest cell voltage detected by a cell monitor with the set target lowest-cell-voltage value, and judges whether or not the lowest cell voltage is near the target lowest-cell-voltage value continuously for a given time period. If the result of the judgment is positive, the target cell-voltage value setting part updates the target lowest-cell-voltage value with a value obtained by decreasing the target lowest-cell-voltage value only by an update width.

Abstract: A driving frequency setting portion is provided. The driving frequency setting portion sets a switching frequency of a switching element on the basis of a notification from a driving phase number switching portion. A ripple current detected by a current sensor is in inverse proportion to inductance of reactor. Since a ripple current becomes the largest in the single-phase driving, in this embodiment, considering both the ripple current and switching loss, a switching frequency for the single-phase driving is set higher than a switching frequency for multiphase driving.

Abstract: In a fuel cell system comprising a fuel cell with plural cells and performing processing for limiting a supply current to a load by performing a compensation computation with respect to a system-request current corresponding to a system-request power requested by the system based on the lowest cell voltage in the cells, the compensation computation being performed for limiting the supply current through a PI compensation using, as a reference value, a current value of the system-request current as of the time when the lowest cell voltage falls below a predetermined lowest-cell-voltage acceptable value, values for gains in the PI compensation for limiting the supply current are different from values for gains in the PI compensation for restoring the supply current.

Abstract: A fuel cell system according to the present invention comprises: a fuel cell and a secondary battery, each acting as a power supply source; a first converter a second converter provided between the fuel cell and the secondary battery and first and second loads; a first inverter provided between the first and second converters and the first load and a second inverter provided between the first and second converters and the second load; a first controller that controls an output of the fuel cell by controlling the first converter; and a second controller configured separately from the first controller, the second controller controlling the second converter, the first inverter and the second inverter to thereby control outputs supplied to the first inverter and the second inverter, including an output from the secondary battery. The first and second controllers are connected so as to be able to communication with each other regarding failure information on respective control targets.

Abstract: A voltage boost converter includes: a main voltage boost portion that has a first switch and a first coil, and that raises output voltage of a direct-current power source by using counter electromotive force of the coil caused by the switch performing a switching action on the coil; and a subsidiary voltage boost portion which has a capacitor that adjusts potential difference between two poles of the switch by amount of electricity stored, and which reduces switching loss of the switch by adjusting the amount of electricity in the capacitor during the switching action, and which has a second switch and a second coil. The second coil is formed by winding a wire around at least a portion of a core formed of a magnetic body. The core is provided with a gap formed of a non-magnetic body. A core region formed of a magnetic body is adjacent to the gap.

Abstract: Provided is a converter control device which detects an on-failure of an auxiliary switch constituting an auxiliary circuit of a soft switching converter and can prevent element failures. A current sensor for detecting the current flowing in a coil is provided between a fuel cell and the. A controller sequentially detects current by use of the current sensor and makes a judgment as to whether or not the detected current has exceeded an overcurrent threshold value stored in a memory (not shown). When the controller judges that the current has exceeded the overcurrent threshold value, the controller judges that a second switching element has an on-failure, and performs a fail-safe operation by stopping the driving of a converter (for example, a U-phase converter) of an auxiliary circuit provided with this second switching element.

Abstract: A fuel cell system includes; a fuel cell which generates electricity by using a fuel gas and an oxidant gas as reaction gases; current control means which controls current of a fuel cell; voltage control means which controls voltage of the fuel cell; and heat value control means which calculates a heat value required by the fuel cell system and decides a target current value of the current control means and a target voltage value of the voltage control means so as to generate the calculated necessary heat amount, thereby controlling the heat value. Thus, it is possible to supply a heat required for the fuel cell system without increasing the size of the fuel cell system.

Abstract: A voltage conversion circuit apparatus that adjusts a timing skew between the switching control of the first switching element and the switching control of the second switching element includes: a skew storage portion that stores a timing skew between the switching controls of the first and second switching elements after the voltage conversion circuit apparatus is manufactured; and a timing adjustment portion that corrects the stored timing skew and thereby adjusts the timing relation between a first pulse signal and a second pulse signal so as to bring within a permissible range the timing skew that occurs when the switching controls of the first and second switching elements are performed by using the first pulse signal and the second pulse signal.

Abstract: A fuel cell system comprising a fuel cell and a secondary cell as power supply sources to a load, in which, during normal operation, a first control part allows a first converter (boost converter at the fuel cell side) to control an output voltage of the fuel cell and a second control part allows a second converter (boost converter at the secondary cell side) to control an output voltage to a first load side, whereas during an occurrence of an abnormality of the secondary cell, the first control part allows the first converter to control an output voltage thereof and the second control part allows the second converter to control an output voltage to a second load side.

Abstract: The present invention detects a failure in an FC converter. A target voltage determination section determines an output target voltage for a fuel cell. A superimposition signal generation section generates a predetermined reference signal to be superimposed onto the output target voltage. A voltage command signal generation section generates a voltage command signal by superimposing the reference signal onto the output target voltage. A frequency characteristics calculation section calculates the frequency characteristics of the reference signal component superimposed on the output voltage of the fuel cell. A failure judgment section judges that a failure occurs in the FC converter if a value of the calculated frequency characteristics is less than the lower limit threshold value of an allowable range established based on reference characteristics.

Abstract: Output voltage of a fuel cell 2 is decreased by a converter 51 to conduct an activation treatment to catalyst of the fuel cell 2, while measuring reduction current by a current sensor 2a while scanning output voltage of the fuel cell 2 over a certain range by the converter 51 as measurement of cyclic voltammetry under the condition that supply of oxidation gas to the fuel cell 2 is stopped from a compressor 31, and this measurement value is integrated by a control device 6. The control device 6 finds a charge amount of electrode catalyst of the fuel cell 2 based on this integration value, decides whether this charge amount is smaller or not than a degradation decision value, and displays this decision result on a display 55. A decision can be made precisely as to whether the electrode catalyst of the fuel cell is degraded or not.