A Time-Coordination Approach for Regenerative Energy Saving in Multiaxis Motor-Drive Systems

An analytical approach for the management of regenerative energies in multiaxis servo-motor-drives, which can operate in parallel packaging/assembly/manufacturing lines, is presented in this paper. This energy management is achieved through a proper time-coordination between the speed commands of multiaxis drives. Moreover, the proposed approach significantly limits the peak value of the ac input current in these systems. It is mathematically proved that a time-delay can significantly increase the amount of utilized regenerative energy, and consequently decreases the amount of dissipated energy. In this paper, a set of closed-form formulas is developed for different acceleration-deceleration time ratios, where motor losses are neglected. The findings of this investigation were experimentally verified using a two-axis permanent-magnet motor-drive system, and the results are presented in this paper. The experimental results are in remarkable agreement with the developed closed-form formulas.