POWER CONVERSION DEVICE

To provide a technique capable of detecting a cooling system abnormality in a power conversion device in which a temperature sensor for measuring a semiconductor element temperature is not included.SOLUTION: The present invention relates to a power conversion device comprising: a semiconductor module including at least one semiconductor element; a cooler which is disposed adjacently to the semiconductor module and in which a coolant flows along the semiconductor module; a first temperature sensor which is disposed upstream of the semiconductor element in the cooler and measures a temperature of the coolant; a second temperature sensor which is disposed downstream of the semiconductor element in the cooler and measures a temperature of the coolant; an identification unit which identifies a loss of the semiconductor element on the basis of the energization status of the semiconductor element; a determination unit which determines at least one decision threshold relating to a temperature rise of the coolant by multiplying the identified loss with at least one reference value relating to previously stored heat resistance; and a decision unit which decides whether or not a differential obtained by subtracting the measured temperature of the first temperature sensor from the measured temperature of the second temperature sensor is less than the decision threshold.SELECTED DRAWING: Figure 2 【課題】半導体素子温度を測定する温度センサを有さない電力変換装置において、冷却系異常を検知し得る技術を提供する。【解決手段】電力変換装置であって、少なくとも一つの半導体素子を有する半導体モジュールと、半導体モジュールに隣接配置され半導体モジュールに沿って冷媒が流れる冷却器と、冷却器において半導体素子に対して上流側に配置され、冷媒の温度を測定する第１温度センサと、冷却器において半導体素子に対して下流側に配置され、冷媒の温度を測定する第２温度センサと、半導体素子の通電状況に基づいて、半導体素子の損失を特定する特定部と、特定された損失に、予め記憶された熱抵抗に関する少なくとも一つの基準値を乗じることによって、冷媒の温度上昇に関する少なくとも一つの判定閾値を決定する決定部と、第２温度センサの測定温度から第１温度センサの測定温度を減算した差分が、判定閾値を下回るのか否かを判定する判定部と、を備える。【選択図】図２