POWER CONVERSION DEVICE

A power conditioner (10) applied to a wind power generation system detects a system voltage (Vr) of a power system (13) and controls output power and output voltage of an inverter (2) based on an active power instruction value (Pr0) and an alternating-current voltage instruction value (Vrr) in a case where a system voltage variation rate (Vr) is within a dead zone (Rdz), and controls an output current (Iiv) of the inverter 2 to stabilize the system voltage (Vr) by use of a voltage drop due to system impedance (Zm) in a case where the system voltage variation rate (Vr) is deviated from the dead zone (Rdz).