Inclusão do modelo do regulador de velocidade nos problemas de fluxo de potência e fluxo de potência ótimo com abordagem trifásica

Abstract

In this work, alternative formulations of the power flow and optimal power flow problems are developed using the positive sequence and unbalanced three-phase modeling, considering the steady-state synchronous generators (SGs) governor representation. Voltage and frequency regulation of distributed generation units (DG) using inverters are also included in the three-phase models. In the power flow, a new concept of a slack bus is introduced in the developed methodologies, allowing any load or generation bus to be the angular reference of the system. The new equations are incorporated into the power flow model, resulting in an augmented system of equations. This new system of equations is solved using the Newton-Raphson method. The proposed power flow allows estimating the frequency deviation due to a variation of system load and generation. Additionally, the active losses are distributed among the generation units regardless of the reference bus choice. The proposed optimal power flow formulations consider the representation of the primary frequency control. The three-phase modeling also includes the representation of the DG unit controls. The proposed formulations can determine the load shedding to maintain the system frequency within the specified limits. Results obtained by the power flow formulations are validated using ANAREDE, ANATEM programs, and real-time simulations using RTDS, demonstrating the effectiveness of the proposed formulations.