An inverter comprising: a diode bridge arranged to rectify an inputted three-phase AC voltage into a DC voltage; an inverter section arranged to convert the DC voltage converted by the diode bridge into an AC voltage and output the resulting voltage; an LC filter having an inductance element (L dc) connected between one output terminal of the diode bridge and one input terminal of the inverter section and a capacitance element (C dc) connected across input terminals of the inverter section; a voltage detecting section arranged to detect a cross terminal voltage (V L) of the inductance element (L dc) of the LC filter; and a control section arranged to control an input current of the inverter section based on a current set point (I a*) so that a transfer characteristic of an I/O voltage of the inverter section becomes a characteristic close to a first-order lag system, the control section comprising: an adder-subtractor arranged to subtract a rotational angular velocity (ω re) of a load from a rotational angular velocity set point (ω re*) and output a difference signal; a PI controller arranged to perform PI control of the difference signal from the adder-subtractor and output a signal; a multiplier arranged to multiply the cross terminal voltage (V L) of the inductance element (L dc) detected by the voltage detector by a gain (k) and output a signal; and an adder-subtractor arranged to subtract the signal from the multiplier from the signal from the PI controller to generate the current set point (I a*). a diode bridge arranged to rectify an inputted three-phase AC voltage into a DC voltage; an inverter section arranged to convert the DC voltage converted by the diode bridge into an AC voltage and output the resulting voltage; an LC filter having an inductance element (L dc) connected between one output terminal of the diode bridge and one input terminal of the inverter section and a capacitance element (C dc) connected across input terminals of the inverter section; a voltage detecting section arranged to detect a cross terminal voltage (V L) of the inductance element (L dc) of the LC filter; and a control section arranged to control an input current of the inverter section based on a current set point (I a*) so that a transfer characteristic of an I/O voltage of the inverter section becomes a characteristic close to a first-order lag system, the control section comprising: an adder-subtractor arranged to subtract a rotational angular velocity (ω re) of a load from a rotational angular velocity set point (ω re*) and output a difference signal; a PI controller arranged to perform PI control of the difference signal from the adder-subtractor and output a signal; a multiplier arranged to multiply the cross terminal voltage (V L) of the inductance element (L dc) detected by the voltage detector by a gain (k) and output a signal; and an adder-subtractor arranged to subtract the signal from the multiplier from the signal from the PI controller to generate the current set point (I a*). an adder-subtractor arranged to subtract a rotational angular velocity (ω re) of a load from a rotational angular velocity set point (ω re*) and output a difference signal; a PI controller arranged to perform PI control of the difference signal from the adder-subtractor and output a signal; a multiplier arranged to multiply the cross terminal voltage (V L) of the inductance element (L dc) detected by the voltage detector by a gain (k) and output a signal; and an adder-subtractor arranged to subtract the signal from the multiplier from the signal from the PI controller to generate the current set point (I a*).