M A I N   N E W S

Decoding the grid maze
Sanjeev Sharma/TNS

New Delhi, July 31
Over the past two days, half of the country has witnessed scenes similar to Bruce Willis blockbuster Die Hard-III where normal life comes to a standstill. There were huge jams on the roads because there were no traffic signals, hundreds of trains were stranded, there was no electricity at home, no TV, no Internet, no working lifts and so on. While in the movie, there was a villain orchestrating a takeover; in India, the crisis was precipitated twice within 24 hours because of grid failure due to overdrawing of power by some states.

A grid is basically a carrier of power. Whenever power is generated, it goes through a grid. When the power is evacuated from the producing centre, a frequency gets attached to it.

It varies between 49.5 to 50.5 and this is the range in which power is distributed. The normal grid discipline is to maintain this frequency. The trouble begins when more power is evacuated to the grid or more power is drawn from it. In the first case, the frequency goes up; while it goes down in the second case.

In India’s power deficit scenario, there is no question of putting in more power into the grid. So, withdrawing more power from the grid is the only option left that could lead to a grid collapse in our country. When the grid mechanism is violated and too much power is withdrawn, the frequency goes down drastically and the grid collapses.

Small fluctuations in frequency are alright, but when there is an abnormal drop in frequency, the grid cannot handle the load and it collapses in the event of a demand-and-supply mismatch.

How does the problem travel across areas?

If there is an extra demand from the North, the supply will first be met from its own grid. However, if there is a shortfall, it may look towards the eastern region that has a surplus to meet its shortfall. As the eastern region also has its own load and in case it is not able to meet the extra demand from the North, both grids may crash, as they did today. So, this becomes a chain effect of rising demand and dropping frequency.

Every generator and distributor of power has a load-dispatch regional centre which is how power is supplied to different regions. Power producers are normally expected to provide a schedule of their generation 24 hours in advance and in case there is an abnormal shortfall due to any reason, that can also lead to grid collapse.

What is POWER GRID

The power grid system is the electrical utility distribution system. A grid is basically a carrier of power. Whenever power is generated, it goes through a grid. India has 5 power grids — northern, eastern, northeastern, southern & western 

ITS FUNCTION

When power is evacuated to the grid from the power station, a frequency gets attached to it. It varies between 49.5 to 50.5 and this is the range in which power is distributed. The normal grid discipline is to maintain that frequency

Why the GRID trips

The trouble begins when more power is evacuated to the grid or more power is drawn from it. In the first case, the frequency goes up; while it goes down in the second case