zopeon
Member level 2
I have Designed a low -pass GM-C filter operating in week inversion with cutoff freq of 185 Hz. I used input signal of 2mV@50Hz for measuring Harmonic Distortn. I did transient analysys with end time =0.4s and then did DFT of Output Voltage.
DFT from 0 to 0.4s, samples 256, window Hamming. I get a peak arnd 0 to 0.8 Hz of -8db and my fundamental is at -60db with 3rd harmonic at -101 db. Should I be concerned abt the peak at dc and arnd 0.8 Hz ??
I also used PSS to get THD , my Beat Freq was 50Hz and method was Shooting with initial time of 2ms. I got 1% THD. The image shows the Harmonic Distortn plot?
Also can u get THD by using PSD of Tran output and then using db10 ?
thank you
zopeon
DFT from 0 to 0.4s, samples 256, window Hamming. I get a peak arnd 0 to 0.8 Hz of -8db and my fundamental is at -60db with 3rd harmonic at -101 db. Should I be concerned abt the peak at dc and arnd 0.8 Hz ??
I also used PSS to get THD , my Beat Freq was 50Hz and method was Shooting with initial time of 2ms. I got 1% THD. The image shows the Harmonic Distortn plot?
Also can u get THD by using PSD of Tran output and then using db10 ?
thank you
zopeon