C. Power oscillation in effect of Ferroresonance
In fact, ferroresonance occurs in effect of nonlinear elements
in the circuit. Consequently, the values of voltage and current
become nonlinear with respect to each other. They can get
different values in the time according to nonlinear impedance
characteristic, hence; waveforms are misshaped so that they
are deviated from sinusoidal form. Misshaped waveforms
consist of orders of harmonics, which depend on the values
and types of nonlinear elements seen by measurement points
in the network. It is able to deviate the frequency of total
waveform of magnitude from nominal frequency. The resulted
frequency depends on value and phase difference of orders
with respect to fundamental. Reciprocally, in such conditions,
another end of the network can get different nonlinear
characteristic, which results in different frequency of total
waveform of magnitude. As a result, ferroresonance is able to
make frequency difference between two points of the network.
It can be inferred that one of the most significant factors,
which affects to oscillation in Ferroresonance is frequency
difference between sources.