Integrating adjustable robust optimal power flow with dynamic stability constraints
One of the primary objectives of the power system operator is to maintain the frequency of an interconnected power network as close to the nominal value as possible. The operator also has to ensure that the transmission and generation systems are resilient enough to avoid voltage and rotor angle instability. This instability may result in voltage collapse. If the gap between power generated and the demand increases, it may lead to damages and blackouts as the grid frequency, and voltage varies from the nominal value. The generation and load balance on the AC power grid can be directly acquired by the system frequency which makes the frequency regulation one of the primary mechanisms to ensure the power balance.
The growing penetration of sporadic renewable energy sources such as wind and solar power has led to the necessity to augment renewable energy sources to the power grid without affecting the stability of the network. The objective of this thesis is to investigate the effects of adding renewable energy sources to the power network. Robust optimal power ﬂow with the control method is used for driving all the synchronous generator states, i.e., generator phase angle, rotor velocity and quadrature axis internal EMF to their respective stable values. This is performed by writing a joint convex formulation of adjustable robust optimal power ﬂow which includes the renewable energy sources with the linear quadratic regulator which stabilizes the generator states after the disturbance while simultaneously ﬁnding an optimal cost of generation. The proposed research can help in understanding better the integration of renewable energy sources in the power network for robust, stable operation and dynamics. The presented formulation is carried out on IEEE 9 and 39 bus systems.