Uninterruptible Power Supply

The uninterruptible power supply in the full name of UPS.

The ups are a device that provides uninterrupted power to us anytime and anywhere which is a common electrical device.

This is used when the main power source fails. It plays the role of an auxiliary in which batteries and supercapacitors are used.

The Main Role of UPS:

Ups work to provide short-term power supply when your mains power supply is disrupted.

Also, it can operate at different temperatures and is also effective in correcting small and large power problems such as power increase or decrease.

This is mainly divided into 2 types.

1.Online ups

2. Offline ups

1. Offline UPS:

This is also known as a standby unit that provides only basic needs. It is given filtered AC power in the primary phase. Whenever the power fails, the transfer switch selects its backup power.

This system acts as a backup when there is any interruption in the main power supply. In this system, the alternating current is already kept low. And is attached to a battery unit connected to a rectifier

When any kind of power is broken, the system comes into motion and the power in its battery is forwarded from DC to AC with the help of an inverter and the load connected to it is supplied.

This system has proven to be cheaper and less costly. It provides more features besides backup. The transfer time can be about 25 milliseconds.

Whose line diagram is shown below.


Off line UPS
The rectifier has no role in the circuit when the main power supply fails. And the storage in the battery is connected to the power inverter to power the load. Once the power is turned on again as usual then the battery is charged again,
2. Online UPS:
In this type of UPS In, the double conversion method is used.
Thus first the AC power is stored in the battery unit. And then converting the same power from dc to ac with the help of Ups which is given to that load.
This type of system requires electrical isolation.
This system is a bit more expensive due to the design of continuous converters and cooling systems.
Thus the rectifier that runs across the input current runs only the direct inverter hence it is also known as double conversion UPS. The block diagram is shown below.
On line UPS
When any kind of power fails, there is no role of a reformer and the power supply meets the load continuously.
The power in the battery meets the load and is connected to the battery.
The static power which is connected to the inverter is given to the load by the transfer switch. Turns on the supply level.
During a major power breakdown, this UPS system operates with zero transfer time. The reason is that the backup source acts as the primary source.
This can take up to 4 to 5 milliseconds transfer time in case of power failure.

Use of UPS System:

Apart from this, many other places are useful for this.

  • Data centers.
  • Industries.
  • Telecommunications.
  • Hospitals.
  • Banks and insurance.
  • Some special projects (events).

Hey, I am Vishnu Patil and I'm an Electrical Engineer and Electrical maestro. I have more than 10 years of experience with electricals. Through ElectricalGang I want to spread my knowledge with everyone else.

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