A Research on the Control Strategy of Coolant Circulation Flow in Internal Combustion Engine.

The electric three-way proportion valve is used for the control of the large and small coolant circulation flows of internal combustion engine. The fuzzy control principle is applied to the control of the opening of proportion valve, and hence the regulation on the large and small coolant circulations of engine is realized. The control strategy is verified on the simulation test bench of engine cooling system with the coolant temperature and its changing rate as inputs and the increment of the opening angle of proportion valve as output of fuzzy controller. The results show that the fuzzy control strategy has high control accuracy and fast dynamic response, and can achieve the rational distribution of the large and small coolant circulations of engine coolant, assuring the engine working on the most suitable coolant temperature condition. [ABSTRACT FROM AUTHOR]