| 摘要 |
PURPOSE: A method for monitoring freezing point of cooling water for a fuel cell is provided to provide information about current freezing point, thereby preventing fracture of a fuel cell stack due to freezing of refrigerant. CONSTITUTION: A method for monitoring freezing point of cooling water for a fuel cell comprises a step of calculating a specific heat of refrigerant circulating per a specific interval(t) throughout a fuel cell stack; a step of calculating refrigerant mixing ratio of the refrigerant and ultrapure water based on the specific heat and temperature of the refrigerant; a step of calculating freezing point of the refrigerant based on the mixing ratio; and a step of turning on a cluster warning lamp for a driver. [Reference numerals] (AA) Start; (BB) External temperature < 0°C; (CC) Calculate a specific heat(C) of refrigerant per a specific interval, t time, based on a sensor measured value or Q, Mw, T400, T410, T410, and old values which are the characteristic values of a system; (DD) Calculate refrigerant mixing ratio based on the calculated specific heat and refrigerant temperature; (EE) Calculate the average value of the refrigerant mixing ratio calculated latest n times; (FF) Calculate the freezing point of the refrigerant based on the average value of the mixing ratio; (GG,LL) Yes; (HH) Final freezing temperature + α < External temperature; (II,MM) No; (JJ) Display a CLUSTER warning lamp; (KK) Final freezing temperature + β < External temperature; (NN) Stop the progress of operation, Store the final freezing temperature; (OO) End |
