COI based Frequency Slow Dynamics Simulation of AC/DC Interconnected Power Systems Incorporating AGC

This paper suggests a structure-preserved frequency slow dynamics simulation model of ac/dc interconnected power systems incorporating AGC function, which will be applied to study relevant control so that power system viability crisis caused by frequency slow dynamics can be released. Then multi-control-area-based dynamic load flow (DLF) is designed based on the suggested model. In this model, the generator speed governor and rotor dynamics, linear load- frequency characteristics, AGC function of area control centers and simplified models for HVDC transmission are all considered. However, at this stage reactive power-voltage sub-problem is neglected for modeling simplicity, hence the interconnected power network is entirely preserved and described by dc power flow in time simulation. The area center of inertia (ACOI) concept is used based on the assumption of uniform frequency in individual control areas similar to conventional DLF. The computer test results from IEEE 30-bus system demonstrate the validity and effectiveness of the suggested model and corresponding algorithm.