A method of controlling a power conversion apparatus which comprises: a first power supply line and a second power supply line; a rectifier configured to rectify a first AC voltage to be inputted into a DC voltage to output said DC voltage to between said first power supply line and said second power supply line; a capacitor provided between said first power supply line and said second power supply line; a reactor constituting an LC filter, together with said capacitor; and a power converter configured to convert a DC voltage (Vdc) supported by said capacitor into a second AC voltage based on a switching signal to be inputted in said power converter and then to apply said second AC voltage to a load to flow an alternating current, said method comprising: detecting a voltage of said reactor taking a potential on the side of said capacitor as a reference; characterized by when at least the first voltage control rate command (ks**) which is a ratio of an amplitude of said second AC voltage to an average value of said DC voltage is smaller than a predetermined value, calculating a correction coefficient (α) which is made smaller as said first voltage control rate command (ks**) becomes smaller; making a correction on said first voltage control rate command to subtract a correction amount obtained by multiplying said voltage of said reactor by said correction coefficient (α), thereby generating a second voltage control rate command (ks*); and giving said switching signal which is generated based on said second voltage control rate command (ks*) to said power converter. a first power supply line and a second power supply line; a rectifier configured to rectify a first AC voltage to be inputted into a DC voltage to output said DC voltage to between said first power supply line and said second power supply line; a capacitor provided between said first power supply line and said second power supply line; a reactor constituting an LC filter, together with said capacitor; and a power converter configured to convert a DC voltage (Vdc) supported by said capacitor into a second AC voltage based on a switching signal to be inputted in said power converter and then to apply said second AC voltage to a load to flow an alternating current, said method comprising: detecting a voltage of said reactor taking a potential on the side of said capacitor as a reference; characterized by when at least the first voltage control rate command (ks**) which is a ratio of an amplitude of said second AC voltage to an average value of said DC voltage is smaller than a predetermined value, calculating a correction coefficient (α) which is made smaller as said first voltage control rate command (ks**) becomes smaller; making a correction on said first voltage control rate command to subtract a correction amount obtained by multiplying said voltage of said reactor by said correction coefficient (α), thereby generating a second voltage control rate command (ks*); and giving said switching signal which is generated based on said second voltage control rate command (ks*) to said power converter. detecting a voltage of said reactor taking a potential on the side of said capacitor as a reference; characterized by when at least the first voltage control rate command (ks**) which is a ratio of an amplitude of said second AC voltage to an average value of said DC voltage is smaller than a predetermined value, calculating a correction coefficient (α) which is made smaller as said first voltage control rate command (ks**) becomes smaller; making a correction on said first voltage control rate command to subtract a correction amount obtained by multiplying said voltage of said reactor by said correction coefficient (α), thereby generating a second voltage control rate command (ks*); and giving said switching signal which is generated based on said second voltage control rate command (ks*) to said power converter.