A lot more than 50% of the compression and pumping systems above 3 MW need a variable-speed drive. Frequently medium-voltage motors fed by frequency converters and parallel shaft gears are selected. Others are using epicyclic gears with a hydrodynamic superimposition drive.

Taking advantage of the condition of the artwork in electric powered motors and frequency converters, the driving program for the superimposition of the earth carrier is founded on a Long term Magnet Synchronous Superimposition (SI) engine and a dynamic Front-End Cycle Converter. So – E stands for Electric.
That is a high-speed gear drive system incorporating components that allow the use of a low-cost constant-speed (electric) driver for a variable-speed application.

More than 50% of the compression and pumping systems above 3 MW require a variable-speed drive. Often medium-voltage motors fed by frequency converters and parallel shaft gears are selected. Others are using epicyclic gears with a hydrodynamic superimposition drive.
It started with hydraulic fluid couplings creating slippage with results very little much better than the throttle.
The design of hydraulic clutches then improved and included a torque converter and a superimposed epicyclic drive.
Variable Frequency Drives (VFD) were developed and, simultaneously, the cost of the shaft trains improved, and so did efficiency. The issue of THD (Total Harmonic grid Distortion) rose and kept VFD out of many applications.

Taking advantage of the condition of the art in electric motors and frequency converters, the driving system for the superimposition of the earth carrier is based on a Permanent Magnet Synchronous Superimposition (SI) engine and an Active Front-End Cycle Converter. Therefore – E stands for Electric.
That is a high-speed gear drive system incorporating components that allow the use of a low-cost constant-speed (electric) driver for a variable-speed application.

All of the over plots were taken by analyzing the existing to the electric motor. In a normal circumstance, the vibration will be monitored and stored on a periodic basis. If the 360 Hz signal is present in the vibration spectrum, it isn’t normally of any concern. If, however, additional unexplained frequencies come in the vibration spectra, then it might be advisable to have a look at both current waveform and the existing spectrum. In the Variable Speed Gearbox webpages that follow, a few examples of problems found out in DC drives and motors are offered.”
It started with hydraulic liquid couplings producing slippage with results not much much better than the throttle.
The design of hydraulic clutches then improved and included a torque converter and a superimposed epicyclic drive.
Adjustable Frequency Drives (VFD) were developed and, at the same time, the price of the shaft trains increased, therefore did efficiency. The issue of THD (Total Harmonic grid Distortion) rose and held VFD out of many applications.