Tese
Estrutura de resposta da demanda para redes elétricas rurais e consumidores irrigantes
Fecha
2022-05-23Autor
Uberti, Vinícius André
Institución
Resumen
Rural grids are composed by radial feeders of great extensions, are located close to
the vegetation and, often, in uninhabited places and difficult access locations. In
general, rural electrical grids feed seasonal loads, which operate only in the harvest
months, and have high levels of technical losses. Often, equipment in these networks
is overloaded, as well as the occurrence of transgressions of the operational limits of
voltage measurements throughout the grid. Inserted in rural areas, consumers with
irrigating rice crops bring their own particularities, such as the lack of automation,
direct start of large loads and use of precarious, obsolete or poorly sized equipment,
which enhances the reduction in the quality of electricity in these feeders. In this
context, this work proposes a demand response structure to rural electricity
distribution networks with a concentration of irrigation consumers and proves that
demand response can contribute to the quality of energy on these grids, reducing
technical losses, improving voltage levels long the grid and avoiding transgressions
of operating limits of the equipment. The proposed structure is composed by an
irrigating controller, located at the rice farms, and a demand response manager,
which is located at the utility operational center. The irrigation controller is developed
through the fuzzy logic and considers crop characteristics and weather forecast
variables to determine the rotation speed of irrigation equipment. The demand
response manager monitors the electrical parameters along the rural feeder and acts
on the irrigation controllers, in response to situations of transgression of the rural
network's operational limits, like feeders or transformer overload and voltage’s limits
transgressions. Results demonstrate technical losses along the grid mean reduction
of 27%, as correction of voltage’s precarious situations, and significant reduction of
overload occurrence in substation and grid equipment. Another important result
occurs in terms of energy efficiency of crop’s irrigation systems, in which energy
consumption reductions start from 49%, during off-peak tariff hours, and 18%, during
the incentivized tariff hours, even in the most adverse weather and farming
conditions.