A power conversion device is provided, which includes a power conversion circuit configured to convert primary power to secondary power and supply the secondary power to a pump and a control circuit configured to cause the secondary power to follow a control command by the power conversion circuit the control circuit being configured to further execute evaluating, on the basis of the secondary power, an amplitude of a driving force of the pump, setting, on the basis of a relationship between an evaluation result of the amplitude and a driving speed of the pump, an amplitude threshold value profile indicating a relationship between an amplitude threshold value and the driving speed, and detecting an abnormality in the pump in response to the evaluation result of the amplitude exceeding the amplitude threshold value based on the amplitude threshold value profile.