Based on the demand of the power quality 's harmonic monitor and the specialty of large scale programmablelogic device, this paper advances a frame of a 24-bit float point FFT module in FPGA.
The soft switching of asynchronous communication among PLC (ProgrammableLogic Con-troller), transducer, touch screen, RS-485 module and PC is introduced.
The digital signal processor (DSP) TMS320LF2407 and the complex programmablelogic device (CPLD) EPM7256E are used as the main control system and the drive module is also designed.