Design of single-phase power analyzer based on FFT analysis

Based on TI's LAUNCHXL-F280049C development board, this paper constructs a single phase power analysis hardware system for single phase AC power supply system. The system includes AC detection module, key/display module, signal conditioning and analysis system and power management module. SCM collects voltage and current data, uses fast Fourier transform to analyze harmonic spectrum, calculates active power, power factor and current THD, and realizes visual display through OLED display. This system pays attention to high precision and high efficiency. Compared with PA reading, the absolute value of relative error of the measured value of current and voltage is controlled within 0.3%, the error of active power and power factor is less than 0.8%, and the error of current THD is about 0.5%. At the same time, the system power consumption is as low as 42mW, reflecting the design concept of high efficiency. In addition, the system follows the standard of electrical isolation, and the measurement scheme adopts transformer technology to ensure safety and reliability. Through the joint debugging of the hardware and software system, the design goal is achieved. This system provides an effective and reliable solution for precision power measurement of single-phase AC power supply system.