Now, uninterruptible power supplies or power protection systems are more efficient, reliable and cause minimum disruption upstream and downstream of their supply. Some suppliers says that rotary UPS to be the answer but others hold differing opinion, saying that latest, advanced designs of static online UPS has made the additional expense of Rotary UPS unnecessary.
Description of Rotary UPS
Rotary UPS are mechanical UPS power protection systems that aim to convert kinetic energy into electrical energy to power connected loads. Two great designs are there:
Rotating transformer depends upon on a regulated isolated rotating transformer. On the other side, induction coupling is consists of a diesel engine, two-speed concentrically-mounted induction coupling and alternator. Irrespective of their design, Rotary uninterruptible power supply begin at around 500kVA in size and range more than or up to 2MVA when arranged in parallel operation. That’s why, their application is saved for huge installations.
If you compare it with a static online UPS power protection system, Rotary UPS produce less dangerous harmonics and get large Meantime Between Failure values. Generation of harmonics is not good as it may lead to poor power quality that can be dangerous to critical device as a complete or partial mains supply failure. It can result to hardware loss and irregular data corruption.
The real quality of mains power supply is evaluated in terms of its voltage, frequency, waveform and the presence of a variety of power issues such as blackouts as well as momentary interruptions. Harmonics are current or voltage waveforms whose frequencies are multiples of the fundamental. In the UK, it is 50Hz and the multiples are ordered into a particular sequence like the 2nd harmonic is 2x50Hz i.e. 100Hz, 3rd harmonic 3x50Hz i.e.150Hz and so on.
Meantime Between Failure or MTBF is a standard indicator of the reliability of a UPS power protection system. It shows the mean processing time between powering-up and device turn off due to failure. The figure is mostly showed in hours.
Higher Prices and Complicated Installation
Installation process of a Rotary UPS is more complicated than a static online UPS. They are a motor generator-based machine and their installation involves vibration, high ventilation, noise as well as elimination of exhaust gas problems.