Abstract
This paper is concerned with 1/2-harmonic self-oscillation of a first-order system involving a thyristor amplifier.
From investigations of an equivalent PWM system, it is shown that the only 1/2-harmonic self-oscillation occures in the instability state.
The method of analysis is based on the equation of the system in the state of the limit cycle. The method is applied to closed-loop systems with two kinds of thyristor amplifier, namely an AC-DC converter and a DC chopper, and rigorous conditions for the 1/2-harmonic self-oscillation are obtained in suitable forms for numerical calculations. The analytical results are verified with the experimental results obtained on voltage stabilizing circuits.
