Abstract:

In order to improve the lifetime and cruising capacity of lead-acid battery in electric vehicle and realize efficient and fast charging,an intelligent charging system is designed.In hardware design,a DC/DC forward converter is used to realize power conversion,a singlechip acts as the core of intelligent control and DS18B20 is employed to collect battery temperature.In software design,a new control strategy is put forward which combines the graded fixed current with plus-minus pulse.By modular design method,software for each function module is designed and the digital PI algorithm is applied to realize graded fixed current.The experiments show that the new control strategy used in the intelligent charger during the charging process can reduce the charging time and improve the charging efficiency.

Key words: intelligent charge;forward converter;control strategy;modular design