Conventionally, a movable object (for example, an electric vehicle) including a rechargeable battery as at least a part of a power source is known. Such a movable object needs to receive power at a charging station if the remaining power of the battery becomes small. In relation to this, a mechanism for managing a state of a power transmitter that supplies power to the movable object is known.
For example, the following Patent Literature 1 describes a wireless power transfer device capable of detecting a malfunction. Specifically, a detection unit of the wireless power transfer device detects a phase difference between an output voltage and an output current output from a power supply main circuit, and a power supply side controller provides a notification indicating a malfunction using a notification device when it is determined that the phase difference is outside a specific range.
Also, in the following Patent Literature 2, a power feeding device including a warning device is described. Specifically, a power transmission ECU determines the presence or absence of a malfunction of a primary resonance coil on the basis of a signal indicating the state of the primary resonance coil detected by a detector and the warning device provides a notification of the presence/absence of a malfunction.