variable speed gearbox

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 using epicyclic gears with a hydrodynamic superimposition drive.

Taking benefit of the condition of the art in electric Variable Speed Gearbox powered motors and frequency converters, the driving program 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 means Electric.
That is a high-speed gear drive system incorporating parts 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 chosen. Others are employing epicyclic gears with a hydrodynamic superimposition drive.
It started with hydraulic fluid couplings creating 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.
Variable Frequency Drives (VFD) were developed and, simultaneously, the price of the shaft trains increased, and so did efficiency. The issue of THD (Total Harmonic grid Distortion) rose and held VFD out of several applications.

Taking benefit of the state of the art in electrical motors and frequency converters, the driving program for the superimposition of the earth carrier is based on a Long term Magnet Synchronous Superimposition (SI) electric motor and an Active Front-End Cycle Converter. Therefore – E stands for Electric.
This 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.

All of the above plots were taken by analyzing the current to the engine. In a normal circumstance, the vibration will become monitored and stored on a periodic basis. If the 360 Hz signal is present in the vibration spectrum, it is not normally of any concern. If, however, other unexplained frequencies appear in the vibration spectra, after that it might be advisable to take a look at both current waveform and the existing spectrum. In the web pages that follow, some examples of problems discovered in DC drives and motors are offered.”
It started with hydraulic fluid 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.
Variable Frequency Drives (VFD) were developed and, at the same time, the price of the shaft trains increased, and so did efficiency. The issue of THD (Total Harmonic grid Distortion) rose and kept VFD out of many applications.