48 V lithium battery micro hybrid system is the most fuel economy vehicle which can be mass produced at present. However, with the irreversible internal resistance increase of the key component 48 V lithium battery, and the capacity continues to decline, the system performance deteriorate. Worst case could be the system not functional in the middle and later age of vehicle life cycle. This paper studies the feasibility of using 48 V super capacitor as the replacement to 48 V lithium battery, and uses a 12 V module of 48 V super capacitor as the traditional 12 V power supply, further reducing the number of components or reducing the demand for parts of 48 V micro hybrid system. This paper analyses the 48 V super capacitor micro hybrid system scheme, based on which a prototype is built, and carries out the vehicle comparative test. The results show that: (1) The performance of 48 V super capacitor micro hybrid system perform comparably with 48 V lithium battery micro hybrid system, and 12 V multiplexing function does not cause power loss of super capacitor; (2) The SOC fluctuation of super capacitor is larger than that of lithium battery, but it can satisfy all test conditions through the strategy; (3) The voltage mutation of super capacitor is smaller than that of lithium battery. It can greatly reduce the impact of voltage on vehicle electrical appliances. The 48 V super capacitor micro hybrid system with 12 V multiplexing function is of great significance.
展开▼
