CROSS-REFERENCE TO RELATED APPLICATION

Priority is claimed on Japanese Patent Application No. 2019-176864, filed Sep. 27, 2019, the content of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a fuel cell system, a method of controlling a fuel cell system, and a storage medium.

Description of Related Art

In the related art, when supplying power from a fuel cell vehicle to an external power supply device, a technology is known for ensuring an operating efficiency of a fuel cell stack by maintaining a flow rate of air supplied to the fuel cell stack at a predetermined flow rate or more, regardless of a state of the fuel cell stack, in a case a state of the fuel cell stack is intermittently switched between efficiency priority driving and output limiting driving or power generation stoppage on the basis of a state of charge (SOC) of a battery is known, (for example, see Japanese Unexamined Patent Application, First Publication No. 2014-56771).

SUMMARY OF THE INVENTION

However, in the related art, variation in electric power demand on the side of devices that are targets for supply of power have not been considered.

An aspect of the present invention is directed to providing a fuel cell system, a method of controlling a fuel cell system, and a storage medium that are capable of stably performing supply of electric power.

A fuel cell system, a method of controlling a fuel cell system, and a storage medium according to the present invention employ the following configurations.

(1) A fuel cell system according to an aspect of the present invention includes a fuel cell; an electrical storage device configured to store electric power generated by the fuel cell; and a control device configured to perform power generation control for at least the fuel cell, wherein the control device acquires a charging rate of the electrical storage device, when the electric power stored in the electrical storage device is supplied to external devices, the control device performs a first control which causes the fuel cell to generate power and increases a charging rate of the electrical storage device and a second control which restricts a power generation output of the fuel cell to be smaller than that in the first control and decreases a charging rate of the electrical storage device, and when a switching condition, in which an electric power demand from the external devices becomes greater than a predetermined electric power or a state in which an electric power demand from the external devices is greater than the predetermined electric power continues for a predetermined time, is satisfied, the control device increases a power generation output generated by the fuel cell during the first control being performed to be larger than that before the switching condition was satisfied.

(2) In the aspect of the above-mentioned (1), before the switching condition is satisfied, the control device may cause the fuel cell to generate power which has a maximum power generation efficiency.

(3) In the aspect of the above-mentioned (1) or (2), after the switching condition is satisfied, the control device may cause the fuel cell to generate power that is an upper limit specified by regulations.

(4) A method of controlling a fuel cell system according to another aspect of the present invention is performed by a control device of a fuel cell system including: a fuel cell; and an electrical storage device configured to store electric power generated by the fuel cell, the method including: performing power generation control for at least the fuel cell; acquiring a charging rate of the electrical storage device; when the electric power stored in the electrical storage device is supplied to external devices, performing a first control which causes the fuel cell to generate power and increases a charging rate of the electrical storage device and a second control which restricts a power generation output of the fuel cell to be smaller than that in the first control and decreases a charging rate of the electrical storage device; and when a switching condition, in which an electric power demand from the external devices becomes greater than a predetermined electric power or a state in which an electric power demand from the external devices is greater than the predetermined electric power continues for a predetermined time, is satisfied, increasing a power generation output generated by the fuel cell during the first control being performed to be larger than that before the switching condition was satisfied.

(5) A storage medium according to another aspect of the present invention, has a program stored thereon, the program being configured to cause a control computer of a fuel cell system including: a fuel cell; and an electrical storage device configured to store electric power generated by the fuel cell, to perform processing of performing power generation control for at least the fuel cell; processing of acquiring a charging rate of the electrical storage device; when the electric power stored in the electrical storage device is supplied to external devices, processing of alternately performing a first control which causes the fuel cell to generate power and increases a charging rate of the electrical storage device and a second control which restricts a power generation output of the fuel cell to be smaller than that in the first control and decreases a charging rate of the electrical storage device; and when a switching condition, in which an electric power demand from the external devices becomes greater than a predetermined electric power or a state in which an electric power demand from the external devices is greater than the predetermined electric power continues for a predetermined time, is satisfied, processing of increasing a power generation output generated by the fuel cell during the first control being performed to be larger than that before the switching condition was satisfied.

According to the aspects of the above-mentioned (1) to (5), it is possible to stably perform supply of electric power.

