Home >Lenze launches smart concept to use braking energy

Lenze launches smart concept to use braking energy

20 May 2016

Many applications with electric drives require frequent accelerating and braking. When accelerating or lifting loads, electrical energy is converted into kinetic or potential energy and much of this can be recovered when braking or lowering the load.

Often this recovered energy is converted to heat using a brake resistor without any economic benefit. But in some applications it is worth passing on this braking energy for another use. Lenze's new r700 takes power recovery to new levels of economic efficiency, practicality and, most importantly, simplicity. Launched at Hanover Fair, the regenerative module is available in two versions with 24 and 48 kW peak power. Its special feature is the separation of supply and recovery paths, permitting an economic system design. Due to its outstanding efficiency of 98% and elimination of external filters, the Smart Energy Recovery quickly pays for itself and impresses with a compact design. Retrofitting existing machinery is a simple task.  

In the past regenerative units for power recovery often failed to make economic sense. They were difficult to install, too complicated to set up and the investment cost far outweighed any power savings. The new Lenze r700 Smart Recovery Unit makes power recovery feasible, even in applications hitherto deemed unprofitable.  By decoupling the power supply and recovery lines, the recovery unit is made simple. This is illustrated by the facts that no EMC filters are required for connection to the mains, and no programming is needed to set up the system. The Smart Recovery Unit is simply connected to the DC bus of the drive or drives. Power is only returned to the mains when there is too much energy in the DC bus.

Typical implementation areas include storage and retrieval units, also other lifting and handling equipment in which a relatively high amount of energy is accumulated as the load is lowered. In such cases the power supply to the drives is dimensioned as normal whilst the recovery unit can be dimensioned only on the surplus braking energy which can be accurately calculated with Lenze Drive Designer software. This leads to compact and economic selections. Depending on the quantity of power recovered, the system pays for itself in around a year.

The new Lenze r700 Smart Recovery Unit breaks new ground for saving energy with dynamic drives. Setting up the system is easy with no EMC filters, no programming and compact dimensions. Energy is returned to the mains reducing electricity bills instead of being lost as heat from braking resistors.

The r700 energy recovery module connects without EMC filters or programming.