Three Pillars Of Wisdom On Electrical Drives

Strategy provides a holistic approach to saving energy in electrical drive applications. As a responsible solution provider and technology partner Lenze, the drive and automation technology specialist, actively supports the current efforts to reduce greenhouse gases and energy costs. With this in mind, Lenze AG has developed a three pillar strategy which provides a holistic approach regarding electrical drives.

It allows the user to identify the potential for improvements in energy consumption. By increasing energy efficiency, energy requirements can be reduced with no detrimental affects on the process. In this way the strategy contributes directly to the reduction in greenhouse gases. In industry electrical drives are among the biggest consumers of energy. As a result, increasing their efficiency is a key factor for efforts to reduce CO2 emissions and energy costs.

Although product oriented efforts will undoubtedly help reduce energy consumption, only a holistic approach focusing on the use of drives and drive components, can maximise the true savings potential. Therefore Lenze is using its competence in drive solutions to introduce a programme that will increase energy efficiency with three main strategic approaches. The Lenze Rightsising approach aims to specify drive systems in such a way that applications are only supplied with the energy they actually need. Drives should not be oversised because efficiency drops sharply with partial loads, so dimensioning should be based on an accurate assessment of the maximum amount of energy required by the application.

Lenze application knowhow together with powerful software dimensioning tools leads to a Rightsised selection. Taking this approach prevents energy from being wasted when operating in a partial load range and reduces material costs. If the amount of energy required by an application fluctuates, a common case with fluid flow and intermittent processes, the energy provided can be matched to the level required using inverter drives. In practice this means that a high degree of efficiency and thereby energy savings can be achieved at a justifiable cost.

The second pillar of the Lenze strategy is to select high efficiency components for the drive installation. Once the drive is correctly dimensioned and, where necessary, uses an inverter, the energy efficiency can be further increased by employing higher efficiency components. Selecting optimised asynchronous motors, or using synchronous motors that are energy efficient by design, on speed controlled drives allows the total efficiency of the installation to be increased.

Similarly energy efficient gearboxes, typically helical and bevel designs, also increase efficiency. The comprehensive Lenze product programme has the perfect solution for each application case. The third aspect is to make use of the braking energy. When applications feed significant amounts of kinetic or potential energy back to the drive, for example in material transport applications, this energy can be re-used.

Lenze currently offers several concepts for using regenerative energy. Energy can for example be exchanged between several axes using a DC bus connection. There are also options of feeding energy back into the electrical mains supply. The Lenze three pillar strategy highlights numerous possibilities for energy saving in the field of electrical drives and provides support during implementation.

As part of this strategy Lenze supports the customer with energy efficient products, tools for dimensioning and comprehensive application know-how. In addition Lenze has published a new brochure entitled "Energy saving solutions" which analyses the possible measures for increasing the energy efficiency of drives and provides guidelines on how these measures should be implemented.