Method for cotrolling condensed water drain using Cotroller for estimating relative humidity and condensed water

摘要

PURPOSE: A method for controlling condensed water drain is provided to change water amount and state, thereby solving a flooding phenomenon and dry-out phenomenon. CONSTITUTION: A method for controlling condensed water drain comprises a step of calculating a water balance type residual condensed water amount in an anode condensed water collector; a step of determining a warning level of a condensed water level sensor when the residual condensed water amount is larger than a value multiplied of a condensed water density and the whole volume of a condensed water collector; a step of determining the failure of the condensed water level sensor when (V_cell < V_cell_TH), (ΔV_cell > ΔV_cell_TH), (hydrogen recirculation blower RPM < RPM_cmd - RPM_TH), (the input pressure of an anode stack > inlet normal pressure map + P_TH), or (the outlet pressure of an anode stack > outlet normal pressure map + P_TH); and a step of controlling a drain valve based on anode water trap estimation. [Reference numerals] (AA) Calculating water balance-based residual condensed water in an anode condensed water collector; (BB) Residual condensed water amount[kg] = Σ_t=0^t=∞[AWT-(Anode condensed water drain valve On) x (Condensed water discharging amount per second)] x Δt + Residual condensed water initial value; (CC) Condensed water level sensor warning; (DD) Drain valve is possibly excessively closed due to the malfunction of a water level sensor; (EE) Cell voltage reduction, hydrogen re-circulation blower abnormal operation, anode side stack input/output pressure abnormality possibly occur due to the intensification of flooding in a stack; (S102) (Residual condensed water amoun > ρ x V1) and (Retention time > t1) ?; (S104) [(V_cell < V_cell_TH) or (ΔV_cell > ΔV-cell_TH) or (Hydrogen-recirculation blower RPM < RPM_cmd - RPM_TH) or (Anode stack input pressure > Input normal pressure map + P_TH) or (Anode stack output pressure > Output normal pressure map + P_TH)) and [(Retension time > t2)]?; (S105) Condensed water level sensor fail; (S106) Initiating the control of AWT estimated value-based condensed water drain valve(Initial value close); (S107) (Residual condensed water amount > ρ x V2) and (Retension time > t3) ?; (S108) Condensed drain valve open; (S109) (Residual condensed water amount < ρ x V2 - V_TH) or (Drain valve open time) > t4)?; (S110) Condensed drain valve close;