Incorporating STATCOM into a Hydro-Thermal Optimal Power Flow Algorithm

Abstract

This paper presents the results of the inclusion of Synchronous Static Compensator (STATCOM) power flow models into a hydro-thermal optimal power flow (HTOPF) algorithm. STATCOM basically introduces the voltage magnitude and phase angle of the source converter into the algorithm. For each incorporated STATCOM, an augmented Lagrangian function was formed. The first and second derivatives of these functions were added to the gradient vector and Hessian matrix of an existing algorithm. The modified algorithm was implemented using MATLAB R2018a and tested on 30 and 57 bus systems. Two and three STATCOMs were, respectively, tested on 30 and 57 bus systems. The results obtained showed that one of the STATCOMs used on 30-bus system injected reactive power that ranges from 8.99 MVAR to 28.22 MVAR while the other one injected reactive power in the range of 8.20 MVAR to 33.20 MVAR. For the STATCOMs placed on the 57-bus system, the range of reactive power absorption by the one placed at bus 5 is 7.83 MVAR to 22.86 MVAR while the one at bus 55 absorbed from 5.06 MVAR to 12.92 MVAR. The STATCOM’s reactive power injection at bus 31 ranges from 4.63 MVAR to 10.35 MVAR. All the lower and higher values were obtained at hours 3 and 7, respectively. While the STATCOMs significantly improved the systems’ voltage profile, the impacts of STATCOM on the total systems daily energy loss, daily energy generations (from both plants), daily fuel cost and hydro plant water worth are insignificant.