Amount of Transmission System Use Determination For Electricity Distribution Utilities
In the last decades the Brazilian electric sector has been going through a series of structural reforms. One of the main changes was the unbundling of the sector and its separation into four agents: generation, transmission, distribution and commercialization. This format required the formation of agencies capable of regulating and overseeing their relationship and ANEEL was created to assume this role. Among ANEEL's attributions was defined the concept of Transmission System Use Amount (MUST). The MUST must be defined with the agents that make use of the transmission system, such as the power distribution utilities. This is not a trivial problem that directly impacts the companies' operations and finances. Moreover, the insertion of renewable and distributed energy sources, as well as stricter recent regulations, introduced new challenges for agents. This paper aims to propose a novel in the methodological approach to determine the MUST for the electricity distributors. The proposed method consists in the determination of distribution profiles for generation and consumption points, scenario simulation by Monte Carlo method, application of probabilistic power flow and, finally, determination of MUST with its associated risk and dispersion measures. Until the stage presented in this paper, the proposed methodology was tested in a small 6-bar system, without the insertion of renewable or distributed generation, considering all connections as a normal type distribution. Results showed the applicability in larger systems mainly caused by the computational automation capacity, that is, the development of software routines that handle manually executed tasks. That method is also flexible to adapt to different scenarios of electrical grids. The advance proposed by this method may collaborate with the electric utilities, increasing the operation and planning predictability.