A design based on DSP digital controlled high switching frequency and constant charging current system

This paper presents a new design method based on DSP control and the PI algorithm of integral separation and variable parameters for constant current battery charging system. The structure and principle of the main circuit, control strategy and software design are introduced in detail. A two-step charging pattern of battery is adopted in this system. In this charging pattern, charging current, charging time, charging principle and terminating conditions of two charging steps can be separately set ahead, and it can realize smooth conversion from the first charging step to the second. The full digital control is realized by DSP chip TMS320F240. This system has been used for charging 12V or 24V battery with constant current in 2A/spl sim/36A. The experimental result shows this charging system has both good steady-state performance and good dynamic performance.