Electromagnetic Transient Modelling Using Dynamic Adaptive Frequency Sampling

Conclusion

The main difficulty in modelling transients via the frequency domain in highly resonant structures is to extract the complete information from its frequency response spectrum. The selection of suitable values for the number of samples and the frequency resolution determines the accuracy of the result. However, neither of these parameters are known prior to simulation. A high Q spectrum requires high resolution samples which if taken at uniform intervals for the FFT will result in a large number of samples. The proposed dynamic adaptive sampling technique takes the samples at intervals according to the requirement at different points of the spectrum. It will, without a priori knowledge of the spectrum, concentrate samples around resonant frequencies. The method has successfully overcome the difficulty without incurring the penalty of increasing computer time.