Electrotechnical Systems

80 Electrotechnical Systems

and must suppress to the maximum possible extent the signals with frequencies in

the range of 250 Hz or higher. The cutoff lter frequency is accepted to be 100 Hz;

lter type is Lowpass, which for the rst-order lter means T = 1/(2π100) = 1.6 ms.

The voltages of the sinusoidal signals are set, according to the frequency growth, as

follows: 100, 40, 30, and 10 V. After simulation, it is seen that THD = 0.51 for Xin

and 0.17 and 0.06 for the lters of the rst and second order, respectively. One can

see a more effective smoothing by the second-order lter, looking at the curves on

the Scope.

Let the inverse problem be actual: an extraction of the high-frequency com-

ponents. Since it is desirable that the signals w ...