An uninterruptible power supply, also known as UPS, is a secondary power system designed to provide stabilized power when there’s an interruption in the primary grid.
Unlike other emergency systems, a UPS allows for instant power supply when a grid outage occurs.
These devices, commonly known as UPS units, are used in computers and other electronics, preventing abrupt shutdowns in case of failures and ensuring a few minutes of operation.
Its power is provided by a battery that is charged by the electrical grid while it is functioning correctly.
Generally, a UPS battery has a short autonomy (between 10 and 15 minutes, depending on the model).
This time is sufficient to save data or wait for the power generator to start operating.
Besides providing power in case of interruption, some UPS models can correct other grid issues like sags, voltage fluctuations, overvoltages, noise, frequency instability, or harmonic distortion.
Types of Supply
There are two types of uninterruptible power supplies: online and offline.
In the online system, double energy conversion occurs.
In the first stage, the alternating current (AC) voltage is converted into direct current (DC) voltage, and in the second stage, the inverter converts the DC voltage back to AC for output.
Thus, the final load has amplitude, shape, and frequency entirely different from the input.
In the offline type (Line Interactive), the inverter is constantly connected.
In case of a voltage drop, the monitoring circuit uses the inverter’s power to maintain supply, ensuring stable power.
