Optimal coordinated control strategy of AGC and AVC based on hierarchical control

Abstract

Negative effects exists between the control commands and control targets of AGC and AVC system, which result in a series of problems such as system security and overshoot. This paper models a coordinated automatic control system of AGC and AVC based on hierarchical control, adopting decomposition-coordination method between active power and reactive power based on time dimension, the design scheme of each control layer is also given. The upper controller optimize active and reactive power coordinately, and then provides the reference setting for comprehensive optimal economic and security. The lower controller improve the control strategy of AGC in advance thus actualized comprehensive energy saving, study of the AGC effects on voltage control is carried out and realize the comprehensive optimal of economic and security by means of suitable voltage control command. Besides, the coordination process checks and corrects the commands in an iterative way, and then get the final comprehensive coordinated commands, which can minimize the negative effects thus maintains the system operating within the multi-objective suboptimal area. Simulations in computer prove the effectiveness of the proposed control system and the strategies