Reconstruction of PWM signal based on double fourier transform and minimum phase system

Since PWM signal is hard to express with formulation in time domain while it is simple in the frequency domain and taking the frequency dependence of the system into consideration, this paper establishes a new way to the reconstruction of PWM signal from frequency domain to time domain. It uses double Fourier transform to decompose the PWM signal in frequency domain, then gets terminal waveforms by using the model of different frequency viewing from motor. Finally, it refactors phase information based on principle of minimum phase system to recovery time domain waveform and then to compare with the waveform of reality. The recovery of the signal is nearly consistent to the real waveform. It can be laid the theoretical foundation of long-line transmission systems of oil exploration in our country.