Random Harmonic Detection and Compensation Based on Synchronous Reference Frame

Abstract EN

Algorithms for harmonic detection and compensation are important guarantees for an active power filter (APF) to achieve the harmonic control function and directly determine the overall performance.

Existing algorithms usually need a large amount of computation, and the compensation effect of specified order harmonic is also limited.

DC side capacitor voltage at sudden change of load is affected by the algorithm as well.

This paper proposes a new algorithm for harmonic detection and compensation based on synchronous reference frame (SRF), in which a band-pass filter with center frequency of 6kth harmonic is designed in fundamental frequency SRF to extract random harmonic current with two different frequencies of (6k±1)th harmonic in stationary reference frame.

This new algorithm can rapidly detect any specified harmonic, and it can adjust the power factor to compensate reactive power.

Meanwhile, it has few impacts on DC side capacitor voltage under complicated operating conditions such as sudden change of load.

The correctness and effectiveness of this new algorithm are verified by simulation and experiment.