Variable Speed Drives

Rexroth, the drives and controls division of the Bosch group is leading the way in the development of innovative products and technology. By doing this, it remains at the forefront of modern technology to provide customers with advanced and reliable solutions for their application needs.

Large-scale facilities are constantly looking for ways to improve energy efficiency. A good starting place is to consider the use of fixed speed fans and pumps where even a small reduction in speed can reduce energy consumption and equal cost savings whilst reducing noise levels. The Rexroth Sytronix speed variable drive is designed for just such fan and pump drive applications.

Sytronix variable speed drives
Investing now into the future as a result of rising energy costs and increasingly cost efficient speed controlled drives offered on to the market, variable speed solutions are on the advance. Using intelligent servo drives to regulate speed and thus the power consumption of the electric motor energy savings of between 30% & 80% can be achieved. Noise reductions of up to 20 dB(A) are possible and in many cases hydraulic cooling requirements are reduced possibly eliminated leading to a more compact design and making further cost savings possible.

Hagglunds (high torque) variable speed drives
For high torque drives Rexroth drive systems provides a hard to beat solution. The Hagglunds motors combined with the low power drive unit (LPDU) has been specifically developed to offer a highly competitive variable speed drive for high torque but low power applications such as screw and belt feeders, mixers, conveyors and other low speed rotating plant.

The Hagglunds motor provides full torque throughout the speed range and has high efficiency. The LPDU low power drive unit has been developed to provide a high quality low cost system to complement the drive motors in power levels up to 50KW. This suits many of the applications in solids handling plants and therefore provides a new opportunity to get the Hagglunds drive solution and benefit from all the advantages without a high investment cost.

Direct hydraulic drives using Hagglunds motors and drive units from Bosch Rexroth make it simple to work across a range of applications in bulk solids handling.

The required torque determines the specific drive motor from the extensive range available in addition to a standard drive (power) unit for the speed range required and the installed power needed. Apart from three connecting pipes, that is all that is required for a successful installation. The control unit can also be included.

With direct hydraulic drives, gearboxes are not required and the motor mounts directly on the shaft to avoid alignment and foundation issues. The electric motor runs continuously with drive control handled by the hydraulics. This means that there are no complex electronics which might be problematic in poor or tough environments. Hagglunds drive systems are actually operating in some of the worst operating conditions without problems, the drive motor is maintenance free and the drive unit requires only occasional filter change and oil inspection.