The Power of Variable Speed Drives
Modern AC variable speed drives [VSD] offer a host of benefits to the user of industrial electric motors. These include reduced mechanical stress at startup, increased system efficiency, and closed loop control of both speed and torque for improved process accuracy.
When you apply VSDs to centrifugal pumps & fans, it is often possible to save vast amounts of energy through optimisation of the motor speed (and power consumption) to match the actual load demanded by the process.
Take a look at this video from Siemens UK which highlights a multi-megawatt installation of low harmonic VSDs and high efficiency motors at a combined cycle British power station :-