VOITH HYDRODINAMIC COUPLINGS USE FOR THE SPEED CONTROL OF A CENTRIFUGAL COMPRESSORS
Main reason for the use of speed control is the saving of energy. Compared to other alternatives for oil flow and pressure control (inlet throttle, bypass and inlet guide vane), speed control is by far the most economical control. It also allows a very wide regulation range, without causing increased wear, for example, as it occurs in throttle valves.Through the control possibility the compressor can be protect- ed effectively against unpermissive operating ranges, for example, like the surge limit.If various operating conditions (e.g. pressure variation, mole weight, flushing, and flow adjustment) are to be realized, the speed control, in combination with other control possibilities, frequently offers the best solution.The speed control is also of valuable services to control the starting and stopping process. There is for example, the quick passage through the critical speed range. Last but not least, we would like to mention the flexibility. If system or process parameters are not yet known, not measurable or changes are to be expected later during operation, final and exact adjustment is possible by speed control.For single-shaft turbocompressors, speed control is a very good alternative for load adaptation. For this purpose more and more electric motors are used worldwide.For speed control of these compressors with high power the Vorecon proved to be successful as hydrodynamic superposing planetary gear. An operating experience from several project over a sufficient period of time confirm the forecasted availability and reliability.