Uninterrupted Power Supply System (UPS)

OPERATING PRINCIPLES, DESIGN AND GENERAL FEATURES OF THE DEVICE

Operating principle

A UPS ensures AC electrical supply to the loads it serves by using batteries. In addition, it filters disruptions, harmonics, voltage spikes etc. that may appear in the grid. Those features are demanded by critical or vital loads that require high quality trustworthy power.

A UPS is made up of 4 sub-systems:

  • Rectifier: converts incoming AC voltage to DC
  • Batteries: stores the required energy
  • Inverter: converts DC voltage to AC at the output
  • By-pass: continuously selects the best grid (aux. or)

Device design

The device has excellent dynamic behaviour with IGBT transistors. It’s controlled by a microprocessor that governs the device in response to different keywords and signals it receives and informs the user of its status.

Control functions:

  • History: last 250 alarms with time and date
  • Automatic control: programmable start up and shut down
  • Diagnostics: visualise and transmit the status of the device
  • Measurements:
  • Vef and Ief of all phases
    • Active, apparent and reactive power
    • Internal system temperatures
    • Output
    • Cos q> and input and output frequency
    • Test: automatic, local/remote, periodic and programmable
    • Digital settings: parameters adjustable by keyboard
    • Configurable: basic system functions can be defined
    • Tips for using the keyboard

General features

  • High power factor at input: 20.95
  • Digitally synthesised perfect sine wave output
  • High frequency stability and output voltage
  • High performance, simplicity and reliability
  • Excellent behaviour with non-linear unbalanced loads
  • Multiprocessor digital control, PWM modulation
  • Interface using a display, keyboard, LEDs and serial communication
  • Built in galvanic isolation transformer

Can optionally operate in parallel with other units

Data sheet

Features

  • Input: Three-phase 220 / 380 / 400 VAC + 15 % – 10% – Frequency 50 / 60 Hz ± 5% – power factor up to 0.9
  • Output: From 5 to 1300 kVA – Frequency 50 / 60 / 400 Hz ± 0.1 % – Single-phase 220 VAC ± 1 % – Three-phase 220 / 380 / 400 VAC ± 1 % – Voltage adjustment ± 5% Vn – allowable cos 0.6 capacitive / 0.4 inductive – Harmonic greater 3 % – Max distor.THD global linear load < 3 % - non-linear load < 5 % - Dynamic response ± 5 % - Response time 30 ms - Crest factor 3 - Yield 80 - 93 %, depending on power
  • Options: Pb or NiCd batteries – 6 or 12 pulses – Anti-harmonics filter – LBP line stabiliser transformer – 28 VDC / 160 a 1000 A Auxiliary source – Redundant – Operation in parallel with other units – Class 1E Anti-earthquake – Output distribution board – Manoeuvre board– Adaptation to diverse regulations (MIL, UL, …)
  • Design: Self-supporting metal cabinet – IP20 to IP54 Protection – Colour RAL 7032 (standard)