The Power and Energy Solutions from SEW-Eurodrive support the sensible use of energy © SEW-Eurodrive

Lödige Industries, based in Warburg, North Rhine-Westphalia, was the general contractor responsible for hall construction and equipment as well as other technical building equipment. In addition to horizontal connecting conveyor technology, the company supplied four storage and retrieval machines for storing and retrieving painted and body shells. These storage and retrieval machines form a central element in the new high-bay warehouse with more than 570 storage locations. They carry out lifting and travel movements simultaneously over seven levels. With a payload of up to 1.5 tons and speeds of up to 3.5 meters per second, considerable regenerative energy is generated during the braking process.

A Movi-C Controller UHX65A from SEW-Eurodrive ensures the interaction of energy storage, drive control and DC link. © SEW-Eurodrive

Because the DC link with supercaps of high power density balances out the peak loads, the size of the power supply can be reduced to around a fifth of the usual value. Despite this significantly lower connected load of 25 kW, the drives (total output 156 kW) can be operated just as efficiently as with conventional technology thanks to the intelligent "Stacker Crane" software module. The software module optimizes the travel cycles of the lifting and travel drives and thus achieves energy savings of up to 25 percent.

Modern frequency inverters are grid-friendly due to the fact that the current and voltage are largely in phase. With a power factor of 0.95, the supply network is only subject to very low harmonic loads. The interaction of energy storage, drive control and DC link is realized by a Movi-C Controller UHX65A from SEW-Eurodrive. Energy management is handled by the Movikit "PowerMode" software module. It records the power and energy data and coordinates the mains connection, the DC link and the energy storage system.

Further savings through warehouse strategy

Chaos storage systems, familiar from online retail, can bring significant energy savings. In Lödige Industries' new high-bay warehouse, bodyshells and painted bodies are stored in a colorful dice. The storage location is determined by the algorithms of the integrated control technology.

Preliminary analyses have shown that energy savings of almost 5 percent can be achieved in the travel movement and more than 25 percent in the lifting movement. Once a storage and retrieval machine has completed its last travel task, it no longer has to expend energy on returning to the hall head, but remains where it is at that moment, saving energy. This enables further energy savings of up to 16 percent.

Safety through state-of-the-art technology

The car manufacturer also sets standards in operational safety in cooperation with the two suppliers. All safety equipment is of the highest standard. For example, Lödige Industries has equipped its stacker cranes with safely reduced speed (SLS - Safe Limited Speed) on all travel axles. This is the only way, for example, that hand-held control panels can be used in the aisle.

Innovation cooperation makes it possible

"Thanks to the close and fruitful collaboration between Lödige Industries and SEW-Eurodrive, we are demonstrating what energy-saving and safe automotive production can look like," confirms Christoph Kesselmeier, authorized signatory of Lödige Systems, a subsidiary of Lödige Industries. And the SEW-Eurodrive project team in charge agrees: "Recycling energy using intelligent, low-loss capacitor technology is a pioneering and sensible step towards sustainably reducing the burden on our environment."

Authors: Petra Ernst-Gutierrez, Head of Marketing & Communications, Lödige Industries, and Gunthart Mau, Press Officer, SEW-Eurodrive

This article appeared in issue 3/23