A device for controlling a power converter that converts a DC voltage (Vdc) including a pulsation component (Vdch) into an AC voltage and outputs said AC voltage to a synchronous electrical motor (M1), comprising: a pulsation component detection unit that detects said pulsation component; and a control circuit that controls said power converter so that a load angle of said synchronous electrical motor is increased in accordance with increase in an instantaneous value of said pulsation component, wherein said control circuit controls said power converter so that a voltage phase which is a phase of said AC voltage is increased in accordance with increase in an instantaneous value of said pulsation component to increase said load angle, generates a first voltage command (VMc*, VTc*) for said AC voltage in a control coordinate system (Mc-Tc) rotating in accordance with a rotation of said synchronous electrical motor (M1), calculates a phase difference (θ0c) of said control coordinate system (Mc-Tc) with respect to a fixed coordinate system (α-β), the device for controlling the power converter is characterized in that the control circuit is configured to: correct said phase difference to increase in accordance with increase in said instantaneous value of said pulsation component (Vdch) to calculate a corrected phase difference (θ0c'), perform a coordinate conversion on said first voltage command using said corrected phase difference to generate a second voltage command (Vu*, Vv*, Vw*) for said AC voltage in said fixed coordinate system (α-3), and generate a control signal (S) for controlling said power converter on a basis of said second voltage command. a pulsation component detection unit that detects said pulsation component; and a control circuit that controls said power converter so that a load angle of said synchronous electrical motor is increased in accordance with increase in an instantaneous value of said pulsation component, wherein said control circuit controls said power converter so that a voltage phase which is a phase of said AC voltage is increased in accordance with increase in an instantaneous value of said pulsation component to increase said load angle, generates a first voltage command (VMc*, VTc*) for said AC voltage in a control coordinate system (Mc-Tc) rotating in accordance with a rotation of said synchronous electrical motor (M1), calculates a phase difference (θ0c) of said control coordinate system (Mc-Tc) with respect to a fixed coordinate system (α-β), the device for controlling the power converter is characterized in that the control circuit is configured to: correct said phase difference to increase in accordance with increase in said instantaneous value of said pulsation component (Vdch) to calculate a corrected phase difference (θ0c'), perform a coordinate conversion on said first voltage command using said corrected phase difference to generate a second voltage command (Vu*, Vv*, Vw*) for said AC voltage in said fixed coordinate system (α-3), and generate a control signal (S) for controlling said power converter on a basis of said second voltage command. correct said phase difference to increase in accordance with increase in said instantaneous value of said pulsation component (Vdch) to calculate a corrected phase difference (θ0c'), perform a coordinate conversion on said first voltage command using said corrected phase difference to generate a second voltage command (Vu*, Vv*, Vw*) for said AC voltage in said fixed coordinate system (α-3), and generate a control signal (S) for controlling said power converter on a basis of said second voltage command. <EOS>