Optimizing Control of a Power System during an Emergency

Abstract: Population growth, infrastructure and economy puts pressure and demand on the existing power supplies. It puts strains on the current power systems which causes instabilities in the systems. This is an ongoing challenge which needs an immediate solution. The objective of this thesis is voltage stability. This is examined with the help of constructing a small power system using a programming language called Matlab. Optimization tools provided by Matlab are used to find the maximum possible pre-contingency load, while still maintaining a stable system. To find feasible solutions in Matlab, system models, such as load models and power line models are simplified. The results show that a system which has experienced a fault can successfully recover by using a linear load recovery model and an exponential load recovery model. Certain constraints, such as generator ramping and limitations on the field voltages in the generators are implemented. Feasible olutions are found although constraints might have made it more difficult under the course of this study. These findings are rough approximations of how a small power system can operate. Though, this can give valuable information on how a more complex system might act before and after a contingency as well as suitable recovery paths. Although the thesis is more suited for those who have some knowledge in control or power systems, a reader without a technical background can enjoy the paper too.