Variable-speed Gearbox for Pumps & Compressors

SETCON SE6 for a 6.5 MW BFP

SETCON is an electro-mechanical variable-speed gearbox designed to control speed in large scale pumps, compressors, fans, and blowers. With a very high overall efficiency, it is the most efficient variable-speed drive technology for your application and pioneering in terms of reliability.

  • Highest overall efficiency up to 97% (reduced OPEX)
  • Power range 4–15 MW
  • Variable output speed up to 15,000 rpm
  • Integrated LOS (incl. lubrication of external units)
  • Footprint optimized for fast replacement of hydraulic gear couplings
  • For Retrofits the existing Main drive remains (reduced CAPEX)
  • Service-friendly and robust design due to low-voltage electronics

= lowest life cycle costs (LCCs) on market

Add-ons: “Soft-start device” – Integrated soft start of Main Drive


As oil and gas prices continue to fluctuate, causing demand for production to vary at refineries, and EU Ecodesign regulations are now stricter, more and more operators are turning to controlled speed drives for their machines. What is standard in other applications, namely adjusting the power required to actual needs, is still not common practice in many areas of industry. If speed control is used, frequency converters (full-scale converters) or hydrodynamic variable speed gear couplings are usually installed. However, when high electrical drive power is required, purchase costs and efficiency losses are often high.
SETCON on the other hand combines all the benefits of conventional drive technologies, thus delivering extremely high efficiency, minimal footprint, and maximum reliability.


Functional description

The SETCON® System consists of a  Gearbox incl. differential gear (planetary gear) (1), Servos in combination with a low-voltage Frequency Converter (2+3) and a Control Cabinet (4). The constant power supply is done by an electric motor as the medium-voltage Main Drive (5). The variable ouput is transmitted to a Driven Machine (6) e.g. a Pump or Compressor. The medium-voltage Main Drive (5) is connected directly to the MV-grid and drives the planetary gear’s ring gear at constant speed. The differential gear’s sun wheel transmits the variable speed through the optional spur gear unit to the Driven Machine (6). The differential gear’s planet carrier is connected to the Servos. The speed of the Servos (2) is controlled firstly in order to ensure the speed at the Driven Machine (6) is variable when the speed of the Main Drive (5) is constant, and secondly to control the torque in the  entire drive train.

Set-up drive train

Principle of the differential gear (1)

Click >here< for the Gear Animation (use google-chrome or firefox browser)

Efficiency Comparison

Total Efficiency: incl. Main Drive and excl. Driven Machine
    • SETCON®: Electro-mechanical Differential System
    • VFD: Variable Frequency Drive incl. Gearbox
    • HDVSD: Hydro-dynamic Variable Speed Drive (hydro dynamic converter)
    • HDC: Hydro-dynamic Coupling