系统的主要功能是在单片机的控制下，将20V~30V的直流电压转换成设定的5V~10V之间的稳定的直流电压输出。系统由分成开环控制的基本功能和闭环控制的拓展功能两部分-The system' s main function is under the control of the microcontroller, to convert the DC voltage of 20V ~ 30V to set a stable DC voltage output between the 5V ~ 10V. System consists of two parts, divided into open-loop control of basic functions and the expansion of the closed-loop control functions