Achieving Economic Operation and Secondary Frequency Regulation Simultaneously Through Local Feedback Control

Abstract

This paper presents an exciting finding for the power industry: The parameters of secondary frequency control based on integral or proportional integral control can be tuned to achieve economic operation and frequency regulation simultaneously within a considerable short period. We show that if the power imbalance is represented by frequency deviation, an iterative dual-ascent-based economic dispatch solving is equivalent to integral control. An iterative method of multipliers based economic dispatch is equivalent to proportional integral control. Similarly, if the controller parameters of the secondary frequency controls are chosen based on generator cost functions, these secondary frequency controllers achieve both economic operation and frequency regulation simultaneously.