Capacidade de hospedagem de geração distribuída baseada em otimização usando o método de injeção de correntes trifásico a quatro fios

Abstract

This paper presents a novel deterministic approach to calculate the maximum hosting capacity of generation to be accomodated in energy distibution systems, based on the formulation of an optimization problem in which the objective function aims to maximize the total amount of active power injected into the network subject to inequality constraints associated with three phase voltage magnitudes, neutral-to-earth voltage (NEV) magnitudes, reverse power flow at the utility substation and voltage unbalance factor. To calculate the load flow in power distribution systems, the Three-Phase Four-Wire Current Injection Method (TPFWCIM) is modeled through equality constraints incorporated into the optimization model. The solution provided by the Sequential Quadratic Programming (SQP) method seeking to combine advantageous computacional time with a viable solution that meets the problem constraints. Computational simulations are performed using a IEEE 33 bus test system and 6.6 kV distribution system based on the modeling of UFJF (Federal University of Juiz de Fora) medium-voltage network in order to prove the applicability of the proposed methodology, showing the impact of the neutral conductor in calculations regarding distributed generation hosting capacity in medium voltage networks. Several scenarios are evaluated by analyzing load conditions, grounding impedance and power factor oof distributed generation units. As a methodological contribution, the four-wire-three-phase formulation for deterministic studies of hosting capacity using the TPFWCIM equations is considered, taking into acount the representation of the neutral conductor in multi-grounded systems, being a valuable tool for studies of maximum accomodation of non-dipatchable energy in medium-voltage systems, ensuring the quality of energy supplied by utilities and delivered to consumers.