A power conversion device, which outputs an alternating current voltage corresponding to an output voltage command (V*), comprising: a direct current power source which outputs a three-level voltage (Vp, Vn); an alternating current power source, one end of which is connected to an intermediate potential point of the direct current power source; an inverter which selects and outputs either the three-level voltage (Vp, Vn)of the direct current power source or the voltage (Vr) of the alternating current power source; a reactor (Lf) which smooths the output voltage of the inverter, and a control section which controls the inverter in accordance with the output voltage command (V*), wherein the control section commands a carrier signal (Sc) of a first frequency when on a first condition that the voltage (Vr) of the alternating current power source is smaller than the output voltage command (V*), and that the difference between the output voltage command (V*) and the voltage (Vr) of the alternating current power source is smaller than a predetermined value, commands a carrier signal (Sc) of a second frequency higher than the first frequency when on a second condition that the voltage (Vr) of the alternating current power source is smaller than the output voltage command (V*), and that the difference between the output voltage command (V*) and the voltage (Vr) of the alternating current power source is larger than the predetermined value, and generates a control signal (G1, G2, Gs1, Gs2) based on the output voltage command (V*) and on the commanded carrier signal (Sc), and that the inverter, in accordance with the control signal(G1, G2, Gs1, Gs2), outputs an alternating current voltage corresponding to the output voltage command (V*). a direct current power source which outputs a three-level voltage (Vp, Vn); an alternating current power source, one end of which is connected to an intermediate potential point of the direct current power source; an inverter which selects and outputs either the three-level voltage (Vp, Vn)of the direct current power source or the voltage (Vr) of the alternating current power source; a reactor (Lf) which smooths the output voltage of the inverter, and a control section which controls the inverter in accordance with the output voltage command (V*), wherein the control section commands a carrier signal (Sc) of a first frequency when on a first condition that the voltage (Vr) of the alternating current power source is smaller than the output voltage command (V*), and that the difference between the output voltage command (V*) and the voltage (Vr) of the alternating current power source is smaller than a predetermined value, commands a carrier signal (Sc) of a second frequency higher than the first frequency when on a second condition that the voltage (Vr) of the alternating current power source is smaller than the output voltage command (V*), and that the difference between the output voltage command (V*) and the voltage (Vr) of the alternating current power source is larger than the predetermined value, and generates a control signal (G1, G2, Gs1, Gs2) based on the output voltage command (V*) and on the commanded carrier signal (Sc), and that the inverter, in accordance with the control signal(G1, G2, Gs1, Gs2), outputs an alternating current voltage corresponding to the output voltage command (V*).