Regenerative energy saving in multi-axis servo-motor-drives

A method for the regenerative energy saving in multi-axis servo-motor-drives is presented in this paper. This energy management is achieved through a proper time-coordination between the speed commands of multi-axis 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, where the motor losses are neglected. The findings of this investigation were experimentally verified using a two-axis permanent-magnet (PM) motor-drive system, and the results are presented in this paper. The experimental results are in remarkable agreement with the developed closed-form formulas.