Fuel cell vehicle

Abstract

A fuel cell vehicle capable of improving energy efficiency by reducing switching loss is provided. The fuel cell vehicle includes: a fuel cell that generates direct current power; inverters which respectively include switching elements and convert the direct current power generated by the fuel cell into alternating current power; a diode that prevents current from flowing from the inverters toward the fuel cell; a step up/down DC/DC converter that adjusts the voltage of the cathode side of the diode; a voltage control part that controls the step up/down DC/DC converter, thereby controlling current output from the fuel cell; and a stop and idle determination part that stops the supply of air to the fuel cell, thereby stopping idling of the fuel cell. The voltage control part reduces the voltage of the cathode side of the diode as the voltage of the fuel cell is reduced by activating the stop and idle determination part.

Description

technical field [0001] The invention relates to a fuel cell vehicle, in particular to a combustion battery vehicle capable of reducing switch loss and improving energy efficiency. Background technique [0002] In recent years, attention has been paid to fuel cell systems as power sources for automobiles. A fuel cell system includes, for example, a fuel cell that chemically reacts a reactant gas to generate power, a reactant gas supply device that supplies a reactant gas to the fuel cell through a reactant gas passage, and a control device that controls the reactant gas supply device. [0003] A fuel cell has, for example, a stacked structure in which tens to hundreds of cells are stacked. Here, each unit has a structure in which a membrane electrode assembly (MEA) is sandwiched by a pair of separators. solid polymer electrolyte membrane. [0004] When hydrogen gas as a reaction gas is supplied to the anode of the fuel cell, and air containing oxygen as a reaction gas is s...

AI Technical Summary

Problems solved by technology

[0009]However, in the above fuel cell vehicles, the fuel cell voltage becomes higher because the load on the fuel cell decreases during the idling stop period.

Therefore, as described above, in order to prevent the current from flowing from the fuel cell through the inverter to the motor or auxiliary equipment, it is necessary to set the voltage of the inverter to be higher than the open voltage of the fuel cell. When the switching loss increases and the energy efficiency cannot be sufficiently improved

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