ONLINE EFFICIENCY ESTIMATION ON THREE PHASE INDUCTION MOTORS USING THE AIR GAP TORQUE METHOD
Marcéu Oliveira Adissi1; Hugo de Souza Pimentel2; José Anselmo de Lucena Júnior2; Júlio César da Silva2; Abel Cavalcante Lima Filho2
1 IFPB - Instituto Federal da Paraíba; 2 UFPB - Universidade Federal da Paraíba
doi:10.20906/CPS/CILAMCE2017-0803
Resumo
Electric motors are responsible for 80% of the electric energy consumed in factories. In order to measure magnitude of mechanical variables accurately, most of the time it is necessary an invasive method placed in the motor, which makes it impractical for equipments with high price and difficult installation. The objective of this work is to apply the air gap torque (AGT) method in order to estimate efficiency in real time in three-phase induction motors, turning the process faster and more reliable. This method was considered the most adequate due to its accuracy and small invasiveness. It was built a test bench of controllable torque to execute the experimental study and to verify accuracy and repeatability of estimation methods in constant load conditions. The essential elements to acquire, process and monitor signals were voltage and current transformers, Hall Effect sensor, A/D converter, laptop and a torque meter. Estimated values presented good precision and repeatability when compared to the ones obtained using the torque meter, showing its potential to optimize industrial processes avoiding various types of losses and to increase energy efficiency.
Palavras-chave: Efficiency; Three phase induction motors; Air gap torque