Microcontroller implementation for monitoring time-varying harmonics from non-linear loads

摘要

The electric grid is becoming more complex due to implementation of distributed generation, widespread use of power electronic devices and all types of dynamic and non-linear loads. As a consequence, harmonic pollution is increasing and it presents non-stationary characteristics that demand advanced signal processing techniques. Several methods have been proposed in order to analyze these time-varying harmonics. Among these methods, this paper shows the implementation of the Slide Window Recursive DFT in a microcontroller system. This method is suitable to track harmonics in time. Moreover, it has fast algorithm which allow it to compute and display time varying harmonics in real time. Hardware and software developments are presented for real time applications. The system is tested using dynamic and non-linear loads and power electronic devices.