Power conversion device

A power conversion device, comprising:

• a voltage conversion circuit;
• voltage detection circuitry including:
• an input voltage detector configured to detect, as a detected input voltage value, an input voltage input to the voltage conversion circuit;
• and
• an output voltage detector configured to detect, as a detected output voltage value, an output voltage output from the voltage conversion circuit;
• and
• control circuitry configured to control the voltage conversion circuit,
• the control circuitry including:
• setting circuitry configured to set, based on a target voltage value which is a target value of the output voltage, a duty ratio of a PWM signal to be given to the voltage conversion circuit, and configured to output the PWM signal based on the set duty ratio to the voltage conversion circuit;
• estimated value calculation circuitry configured to cyclically calculate, based on the detected input voltage value and the detected output voltage value, an estimated duty ratio value which is a duty ratio of the PWM signal supposed to be output from the setting circuitry to the voltage conversion circuit with a premise of a relationship between the detected input voltage value and the detected output voltage value;
• and
• abnormality detection circuitry configured to detect abnormality of the voltage detection circuitry based on a change of a difference value, the difference value being a cyclically calculated difference between an updated estimated value and a comparison reference value, the updated estimated value being the estimated duty ratio value newly calculated by the estimated value calculation circuitry, the comparison reference value being based on the estimated duty ratio value calculated by the estimated value calculation circuitry in a cycle prior to a cycle in which the updated estimated value is calculated.