Optimal power flow considering non-smooth generation cost function and emissions using AMPL and Knitro solver

Resumo

The Optimal Power Flow (OPF) problem aims to analyze the planning and operation of electrical power
systems and has been widely used due to the benefits that can be obtained. This work analyzed the application of
language AMPL (Modeling Language for Mathematical Programming) and the Knitro commercial solver, to solve
the Economic and Environmental Dispatch (EED) problem, modeled as an OPF. In the proposed OPF modeling
were considered equality constraints such as active and reactive power balance and inequality constraints such as
generator, transformer and Shunt VAR compensator constraints that represent the operational and physical limits
of the system. The problem was implemented as single and combined objective functions aiming minimize the
generation cost with and without valve point effect and emissions. These characteristics make the problem more
complex, nonlinear, and non-convex. Additionally, a simple heuristic was proposed to deal with the discrete
characteristic related to the value of transformer taps. The IEEE 30-bus test system was presented to illustrate the
application of the proposed problem. Finally, the obtained data were compared with the literature and the
superiority of the approach was demonstrated.