Application of Ultra-Local Models in Automatic Generation Control with Co-Simulation of Communication Delay
Abstract: This paper
applies the ultra-local models (also labeled as intelligent PID controllers) to
Automatic Generation Control (AGC) in a Multi-Area power system (New England 39 Bus) in
the presence of communication delay. Given the fast development of smart grid in the
past years, power system and communication network are coupled much more tightly than
before. Therefore, the independent ... read morestudy of the two domains or simplistic modeling the
communication delay in the power system simulation environment is no longer effective
and convincing. In our work, the power system model containing AGC is built in
Simulink/Matlab, and the communication network is co-simulated in Network Simulator 2
(NS2) through PiccSIM, a simulation platform for (wireless/wired) networked control
systems. A careful comparison is made between the performance of intelligent-P (iP)
controller and the conventional PI controller under the co-simulation environment of AGC
with time-varying wired communication delay. The results show the two controllers are
largely equivalent for relatively small frequency deviations. However, intelligent-P
controller performs better than conventional PI controller under more severe system
variations, such as large communication delay. The avoidance of integration in the
intelligent-P controller makes anti-windup algorithm unnecessary, which enhances the
applicability and the simplicity of controller tuning. In addition, the co-simulation
results also demonstrate that the system is more sensitive to the communication delay of
control signals from the area control center to the distributed generators than to the
delay of tie-line active power measurements. This conclusion is very illuminating that
the distributed control mechanism becomes a promising alternative for the control
mechanism applied widely now. Instead of a one control center per regulating area, every
generator participating in AGC could have its own local controller. The distributed
generator controllers can communicate with each other and share the needed information.
This fully-distributed automatic generation control (AGC) is more tolerant of
communication delay, and thus more robust and stable under various
Thesis (M.S.)--Tufts University, 2018.
Submitted to the Dept. of Electrical Engineering.
Advisor: Aleksandar Stanković.
Committee: Aleksandar Stanković, Ronald Lasser, and Jason Rife.
Keyword: Electrical engineering.read less