Energy Optimized Drive Systems Design

Abstract

Electric drives represent about 70 % of the industrial power consumption. The total saving potential in Germany by consistently using energy optimized drive systems has been estimated to be 20 THh. This corresponds to the equivalent of 8 fossil-fuel power station blocks. High efficiency motors alone represents an energy-saving potential which is a factor of 7...8 smaller. Technical measures for the purpose of energy saving have been implemented in, the standard components available today. No fundamental new developments are required. Essential for practical application is:

• Move away from conventional fixed-speed drives with downstream loss-intensive adaptation to the process requirement, whereby the excess energy available is dissipated, i.e. is converted into heat

• Move towards low-loss variable speed electric drives (VSD) with optimum process control, whereby only the required energy is made available

• Further more, it should be ensured that low-loss system components are consequentially used; e.g. no worm gears and no throttle- or bypass controls.

Electronically-controlled VSD’s allow energy-saving operations in all operating phases, especially at partial loads, partial speeds as well as when accelerating- and braking. The capital investment costs are generally amortized in a relatively short time from the significantly lower operating costs.