More than 50% of the compression and pumping systems over 3 MW require a variable-speed drive. Often medium-voltage motors fed by frequency converters and parallel shaft gears are selected. Others are employing epicyclic gears with a hydrodynamic superimposition drive.
Taking benefit of the condition of the art in electrical motors and frequency converters, the driving program for the superimposition of the earth carrier is founded on a Permanent Magnet Synchronous Superimposition (SI) motor and a dynamic Front-End Cycle Converter. Therefore – E stands for Electric.
That is a high-speed gear drive system incorporating elements that allow the use of a low-cost constant-speed (electric) driver for a variable-speed application.
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.
It started with hydraulic liquid couplings creating slippage with results very little much better than the throttle.
The look of hydraulic clutches then improved and included a torque converter and a superimposed epicyclic drive.
Adjustable Frequency Drives (VFD) were developed and, simultaneously, the expense of the shaft trains improved, and so did efficiency. The problem of THD (Total Harmonic grid Distortion) rose and held VFD out of many applications.
Taking advantage of the condition of the art in Variator Gearbox electric powered motors and frequency converters, the driving program for the superimposition of the planet carrier is based on a Long term Magnet Synchronous Superimposition (SI) electric motor and a dynamic 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 engine. In a normal scenario, the vibration will become monitored and kept on a periodic basis. If the 360 Hz signal exists in the vibration spectrum, it is not normally of any concern. If, however, other unexplained frequencies appear in the vibration spectra, after that it would be advisable to take a look at both the current waveform and the existing spectrum. In the webpages that follow, some examples of problems uncovered in DC drives and motors are presented.”
It started with hydraulic fluid couplings making slippage with results not much better than the throttle.
The look of hydraulic clutches then improved and included a torque converter and a superimposed epicyclic drive.
Variable Frequency Drives (VFD) were developed and, at the same 
time, the expense 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.