In the case where a predetermined condition related to a load is satisfied in a first state in which electric power is supplied from a second power supply source to the load via a second electric circuit and not supplied to the load via a third electric circuit when electric power cannot be supplied from a first power supply source to the load, a control unit controls a converting unit and a switching unit to establish a second state in which electric power is supplied from the second power supply source to the load via the second electric circuit and the third electric circuit.