Patent attributes
A hybrid electric vehicle (HEV) and method of operation includes a thermal management system (TMS) that maintains optimal battery temperature operating ranges. The TMS includes a controller, heater, pump, and valves that control a flow rate of a convective fluid about the battery and other components. The TMS responds to battery temperature and differential signals, converting them into pump speed and heater signals utilizing a fuzzy logic multidimensional membership function (MF) that improves performance while reducing energy consumption by generating real-time, smoothed pulse width modulated (PWM) pump speed and heater signals. The MF capability requires less processing power than prior systems, which in turn enables improved response time to battery thermal and temperature rate changes during HEV operation. The MF utilizes embedded temperature and differential MFs that generate respective, real-time, tuned signal conversion factors, without the need for calibration look-up tables, to generate the PWM pump and heater control signals.
