Case study: Adaptative overcurrent protection scheme applied to an industrial plant with cogeneration units

Although digital protection has been widely employed in power system industry, many protection practices are still the same employed to electromechanical relays. Consequently, the potentialities and benefits of digital relays are not fully explored. In this context, this work presents the advantages of digital protection to coordinate overcurrent relays in an industrial plant with three cogeneration units, resulting in three operating scenarios. It is shown that conventional practices did not result in an efficient solution and an adaptative protection scheme was proposed, which guaranteed overcurrent coordination for all the considered operating scenarios.