A vehicle system of the present invention includes: a motor configured to drive a vehicle; a high voltage storage device connected to the motor and configured to supply the motor with power; a fuel cell connected to the high voltage storage device and configured to charge the high voltage storage device; and a low voltage storage device connected to the fuel cell. The vehicle system includes: a bidirectional first voltage converter interposed between the fuel cell and the high voltage storage device, and configured to adjust a voltage at either of the fuel cell or the high voltage storage device and to supply power to the other; and a second voltage converter interposed between the fuel cell and the low voltage storage device, and configured to adjust a voltage at the low voltage storage device and to apply the adjusted voltage to the fuel cell. The vehicle system is characterized in that the vehicle system includes a bidirectional third voltage converter interposed between the high voltage storage device and the low voltage storage device, and configured to adjust a voltage at either of the high voltage storage device or the low voltage storage device and to supply power to the other.

The subject matter of this specification can be embodied in, among other things, a hydrogen fuel cell anode control system including a hydrogen inlet configured to receive pressurized hydrogen, a hydrogen outlet configured to be fluidically coupled to an anode manifold of a hydrogen fuel cell, a recirculation inlet configured to receive overflow hydrogen from the anode manifold, a hydrogen pressure regulator configured to receive pressurized hydrogen from the hydrogen inlet, a hydrogen recirculation module configured to mix hydrogen received from the hydrogen pressure regulator and the recirculation inlet, and provide a hydrogen mixture to the hydrogen outlet, a differential pressure measurement module configured to measure a differential pressure between the anode manifold and a cathode manifold of the hydrogen fuel cell, and a controller configured to control at least one of the hydrogen pressure regulator or the hydrogen recirculation module based on the measured differential pressure.

In a power control device for a vehicle in which an electric motor for driving the vehicle to travel is supplied with power from a battery mounted on the vehicle and a fuel cell, a control unit sets a target charging rate (SOCt) of the battery in such a manner that the target charging rate decreases as a remaining fuel amount (Qf) of the fuel cell decreases after the power generation of the fuel cell is started during high-output/high-speed travelling and controls a power generation output (Pf) of the fuel cell based on a difference between the target charging rate (SOCt) and a current charging rate (SOC).

The present disclosure is made in order to reduce inaccuracy of current sensors. A fuel cell system 100 comprises a converter 150 configured to convert output voltage of the fuel cell 1, and a current sensor CS1 including a preliminarily magnetized magnetic core MC1 and configured to measure current flowing in the converter 150 from the fuel cell 1. A controller 160 comprises, as driving modes of the fuel cell system 100, a first driving mode DM1 in which a maximum current value IL1max in a target circuit of current measurement by the current sensor CS1 is lower than a current value for preliminary magnetization of the magnetic core and a second driving mode DM2 in which the maximum current value IL2max in the target circuit is higher than the maximum current value IL1max in the target circuit in the first driving mode DM1. When an accumulated temperature value IT of the current sensor CS1 in the first driving mode DM1 has exceeded a threshold ITth, the second driving mode DM2 is executed and subsequently the first driving mode DM1 is executed.

A fuel cell system comprises an electrochemical fuel cell stack for generating electrical power. A load circuit is switchably coupled to the fuel cell stack for periodically receiving a discharge current from the fuel cell stack during an energy dissipation phase, such as an air stall operation for conditioning the fuel cell stack. A protection circuit is coupled to the load circuit, configured to monitor a cumulative energy dissipation level during an energy dissipation phase and to abort an energy dissipation phase if the cumulative energy level reaches a predetermined threshold. In this way, lower specification resistor components can be used for stack conditioning.

A fuel cell system includes: a converter that boosts a voltage input from a fuel cell; a voltage control device that can control a voltage input from an electricity storage unit; a drive circuit that converts direct-current electricity input from the converter and the voltage control device into alternating-current electricity and outputs the converted electricity to the load; a relay that switches between a connected state in which the fuel cell and the drive circuit are connected to each other and a disconnected state in which they are disconnected from each other; and a controller that determines whether the relay is welded by different determination methods using an index current value between the relay and the fuel cell and a first index voltage value between the relay and the converter when the fuel cell system is to be stopped.

A fuel cell system including a radiator disposed on an electronic part cooling line, the cooling line configured to pass through an electronic part and to circulate a coolant, the radiator being configured to cool the coolant, a coolant pump configured to pump the coolant to circulate the coolant in electronic part cooling line, and a controller configured to determine whether air bubbles are generated, based on a change in a current of the coolant pump while the coolant is circulating and control an air bleeding through the coolant pump.

The subject matter of this specification can be embodied in, among other things, a hydrogen fuel cell anode control system including a hydrogen inlet configured to receive pressurized hydrogen, a hydrogen outlet configured to be fluidically coupled to an anode manifold of a hydrogen fuel cell, a recirculation inlet configured to receive overflow hydrogen from the anode manifold, a hydrogen pressure regulator configured to receive pressurized hydrogen from the hydrogen inlet, a hydrogen recirculation module configured to mix hydrogen received from the hydrogen pressure regulator and the recirculation inlet, and provide a hydrogen mixture to the hydrogen outlet, a differential pressure measurement module configured to measure a differential pressure between the anode manifold and a cathode manifold of the hydrogen fuel cell, and a controller configured to control at least one of the hydrogen pressure regulator or the hydrogen recirculation module based on the measured differential pressure.

Various embodiments of the present disclosure provide a fuel cell system configured to modulate the flow of oxidant through the fuel cell system to maintain a desired temperature at the fuel cell stack. The fuel cell system is configured to control the flow of oxidant to maintain the desired temperature in the fuel cell stack based on temperature measurements of fluid outside of the fuel cell stack.

A fuel cell power controller tracks load current and fuel cell output voltage, and alerts on excessive fuel cell ramp rate, so another power source can supplement the fuel cell and/or the load can be reduced. A power engineering process makes efficient use of available fuel cell power by ramping up power flow rapidly when power is available, while respecting the ramp rate and other power limitations of the fuel cell and safety limitations of the load. Power flow decreases after an alert indicating an electrical output limitation of the fuel cell. Permitted power flow increases in response to a power demand increase (actual or requested) from the load in the absence of the alert. Power flow may increase or decrease in a fixed amount, a proportional amount, or per a sequence. A power controller relay may trip open on a low fuel cell output voltage or high load current.