A power conversion device supplies power to a load. The power conversion device includes a power conversion unit, a control unit, a noise suppression unit, and an error detection unit. The power conversion unit receives power from a first power source. The control unit controls the power conversion unit. The noise suppression unit is connected between the first power source and the power conversion unit and outputs a noise suppression signal to suppress noise generated from the power conversion unit. When an error condition is established, the error detection unit detects an error. The error condition indicates that the error has occurred in the power conversion device or the load. The error condition includes a condition that an amount of noise generated from the power conversion unit is larger than a reference value.