Drive Dynamic Analysis – The Key to Optimal Drive Performance

The paper presents concept and application of mathematical and simulation model of variable-speed drives (hereafter VSD or VSDs). The models were/are used in rolling mills engineering, commissioning and maintenance. The VSDs are the main actuators there. In order to reach optimal performance in terms of material tolerances, wear and tear, and reliability it is necessary to have good VSD control which meets not only technology targets but also properties of the VSD mechanical train (set of motor rotors, shafts, gear boxes, couplings, clutches, spindles, working and backup rolls, etc.). Only the optimal VSD control and appropriate operation and maintenance can ensure trouble-free operation and long lifetime of the VSDs. We have been dealing with the VSDs models since 1990. Since then we have used the models in many practical applications. Currently, we concentrate mainly on an optimal and advanced interstand section control. Apart from various PID control strategies, also Fuzzy control has been tested and analyzed. The paper mentions some of our experiences we have achieved in this area.