To use a shunt for detecting the output current of an inverter and arm short-circuiting in, and the output overcurrent of the switching elements comprising the inverter, and to obviate expensive transformers.

An inverter device is provided with a first switching element 21 and a second switching element 22 which have anti-parallel diodes connected in series with both the ends of a direct-current voltage power supply 1. The inverter device is provided with a first shunt 31 placed between the first switching element 21 and the second switching element 22, a second shunt 32 placed between the connection point between the first shunt 31 and the first switching element 21, a first potential difference amplifier which amplifies the output voltage of the first shunt 31 and a second potential difference amplifier, which amplifies the output voltage of the second shunt 32. Furthermore, the connection point between the first shunt 31 and the second shunt 32 is connected with a ground common to the potential difference amplifier and the second potential difference amplifier.