Feeder Automation used in the smart distributed network is a very efficiency measure and also the foundation of Distributed Automation System. So the research in this area can make our power supply reliable and quality. Traditional FTU has many bugs such as bad real-time performance, less control function and not enough data analysis ability. In this paper, introduces the chip of TMS320F2812 from TI company as its main controller and this DSP can matches the processing speed; it takes the AD7862 as its AD part to avoid the sampling phase errors; also in this paper RTL8019AS is adopted to implement the communication with TCP/IP protocol. The data collected is saved in the storage medium with the format of COMTARDE and sent to the host computer through serial port for graph drawing, and then FFT algorithm is used for analysis. The FTU designed in this paper has the features of high calculating speed, strong real-time quality and strong data-processing ability. It identified that design of DSP-based FTU is better, feasibility and practicability.