Off-line tuning is especially useful in the process control industries as it enables validation of controller design without any plant or equipment shut down. The REC computes a motor torque correction signal from shaft torque measurement, which in turn is applied to the mechanical system at a specific resonant frequency. A real-time interface allowed the two models to exchange information. The first time the REC was turned ON, it totally eliminated the mechanical system resonance. VisSim model of GE industrial drive system with Resonance Eliminator Controller.
Upper plot shows amount of correction applied to motor torque.
Lower plot shows drive speed. If incorrectly designed and not thoroughly tested, it can cause motor, shaft, and coupling failure, resulting in a process outage costing millions of dollars. For more details, request the DuPont case study.