Beat Frequency Oscillation Analysis for Voltage Regulators in Telecom Power System

The interaction of voltage regulators (VRs) in a power system may introduce instability, oscillation, or other performance degradation issues. This paper studies the beat frequency oscillation caused by two cascaded VRs in a telecom power system. VRs' stand-alone mode, low frequency interaction, and high frequency interaction are analyzed through a harmonic state space model to clarify the root cause of the beat frequency oscillation. An equivalent circuit model is developed for the cascaded VRs system to describe its beat frequency oscillation and design recommendations are proposed to limit such oscillation.