Actions to improve the power supply quality of Eletronorte's industrial customers

This paper presents recent experiences of Eletronorte (Brazil) concerning electric energy quality, with efforts involving industrial customers and the facility, where tools of total quality, digital simulations, identification of production processes and field tests were used. The activities began due to complaints from industrial customers of the city of Manaus, related to interruptions in its productive processes caused by power system voltage variations. Those complaints were characterized as being mainly in consequence of short-time undervoltages (voltage sags). In this way, the paper describes the technical analysis and field tests, as well as the solutions adopted to reduce the number of interruptions in the customers plants.