While power supply from of the Central stations in North and East to Andhra Pradesh was impacted due to Northern Grid collapse, the State grid remained stable and unaffected.
The utilities in Andhra Pradesh have adopted 24x7 grid monitoring system which enables them to detect problems and remedy them. The automatic disturbance control mechanism and the island mode grid mechanism helped the State insulate itself against Northern grid collapse early today.
This protected Andhra Pradesh from possible blackout.
The normal frequency at which electricity is transmitted through the Northern Grid ranges from 49.5 to 50.2 Hz, and when the grid collapsed it was at 2.35 a.m., the grid frequency was 50.46 Hz, a few notches above normal frequency.
According to experts, grid overloading could be one of the probable reasons for the collapse. Power supply across nine states of North India including Delhi, Haryana, Punjab and Rajasthan were hit due to grid failure. The Northern Grid caters to 28 per cent of the country's population.
Reviewing the grid developments, Mr Hiralal Samaria, Chairman and Managing Director of AP Transco suggested the need to ensure grid stability in the State so that there is no disruption in power supply. He emphasised the need to maintain grid frequency between 49.5-50.2 Hz, according to the Indian Electricity Grid Code.
There has been no power blackout in the Southern grid since the September 11, 2001, the last time there was grid collapse. It was due to an electrical fault in a neighbouring State which had led to cascading impact on all the Southern states. However, Andhra Pradesh was saved.
States violating the code are being penalised. Apart from initiating major steps for grid security, the Government has earmarked funds to strengthen the T&D infrastructure over the next four years.