Design of Uninterruptible Power Supply/UPS

Problem Statement:

Design a 1kVA UPS powered by a single phase 220V/50Hz AC. You may consider one of the following design options:

a.         A rectifier as battery charger+ DC-DC Boost converter + Sinusoidal PWM Inverter

b.         A rectifier as battery charger + Full bridge DC-DC converter using pulse power transformer+ Sinusoidal PWM Inverter

c.         A rectifier as battery charger + Sinusoidal PWM Inverter + Step up transformer

Charging current of battery must not exceed 15A and you must take care of input power factor.

What is an Uninterruptible Power Supply?

An uninterruptible power supply, also uninterruptible power source, UPS or battery/flywheel backup is an electrical apparatus that provides power to the system which it is connected to i.e household assembly of electricity run devices, offices, computer run etc when the power from the main grid gets disrupted or cut off and it can also provide emergency power to a load when the input power source, typically mains power, fails.

UPS is a device that provides battery backup when the electrical power fails or drops to an unacceptable voltage level. Small UPS systems provide power for a few minutes; enough to power down the computer in an orderly manner, while larger systems have enough battery for several hours. In mission critical data centers, UPS systems are used for just a few minutes until electrical generators take over.