Optimal Parameter Design by NSGA-II and Taguchi Method for RCD Snubber Circuit

A genetic algorithm and Taguchi method were used to optimize parameters for the residual-current device (RCD) snubber circuit of a DC-DC flyback converter. The most suitable algorithm was determined by using test functions to compare performance in three multi-objective optimization methods: non-dominated sort genetic algorithm-II (NSGA-II), multi-objective particle swarm optimization (MOPSO), and multi-objective differential evolution algorithm (MODE). Comparisons of coverage rate, distance between non-dominant solutions, and maximum walking distance showed that NSGA-II was superior to both MOPSO and MODE. Therefore, NSGA-II was used to obtain parameter values for the RCD snubber circuit. However, practical application of the parameter values was limited because the values could not meet the specifications required for real-world circuits. Thus, the parameter values obtained by NSGA-II were used in further factor-level experiments performed by Taguchi method. The experimental results indicated that, compared to previous design methods, the proposed NSGA-II and Taguchi method obtains better parameter values for the RCD snubber circuit.