Some Nonlinear Feedback Control Systems under high gain conditions exhibit the phenomenon of subharmonic instability, or contain subharmonics of the fundamental output frequency. A general discussion of subharmonics in nonlinear systems is followed by an investigation of ripple instability in a forced limitcycling voltage regulator containing a thyristor or SCR bridge utilizing an 0NOFF switching scheme. A digital computer program is used to simulate the dvnamic response of the system under different loading conditions and for different reference voltage levels.

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http://archive.org/details/investigationofs1094512485

Major, United States Marine Corps