Second unit at Madras Atomic Power Station to re-start by September

The second unit at the Madras Atomic Power Station (MAPS) is likely to start functioning only by the end of September, when the installation of a new transformer is expected to be completed, a senior official said Thursday.

The unit, belonging to India's atomic power plant operator Nuclear Power Corporation of India ltd (NPCIl), was shut down last month after a fire damaged its transformer.

"We have placed an order for a new transformer with TElK (the Kochi-based Transformers and Electricals Kerala ltd). It will take three months for us to restart the unit. By September end the unit is expected to start functioning," MAPS station director T.J. Kotteeswaran told IANS over phone from Kalpakkam, around 70 km from here.

According to him, TElK has started its part of the work and it would cost NPCIl around Rs.8 crore.

The burnt transformer is around 30 years old, and was supplied by Asian power equipment major Bharat Heavy Electricals ltd. (BHEl). Similar transformers are not in its production line.

Queried about the earlier plans of bringing a BHEl transformer from its Jhansi unit in Madhya Pradesh, Kotteeswaran said: "Actually, it was not made for us. Some modifications would need to be done to suit our needs."

He said the time that BHEl would take to do the modifications and transport the transformer would be more or less the same as the time TElK would take to manufacture and supply it to the Chennai unit. 

"As TElK will be making the transformers as per our needs, we decided to go for that," Kotteeswaran said.

Speaking to IANS, a BHEl official said: "We had located a transformer that can be modified to suit MAPS. The transformer was slated for Syria. But owing to the problems in that country the shipment has been delayed at the request of the Syrian client."

The MAPS, run by NPCIl, has two reactors of 220 MW each, but they have been functioning below their rated capacity owing to paucity of fuel.

On April 15 morning when the reactor was operating at 110 MW, the unit tripped due to a fault in the generator transformer's high-voltage bushing, and the reactor was shut down. The unit was restarted prior to that after a 40-day maintenance shutdown.

Due to the generator transformer failure, the reactor turbine stopped and the reactor was gradually shut down, following due procedure.

Kotteeswaran said the first unit is operating normally, feeding 170 MW to the grid.

In August 2012, two reactors at MAPS shut down automatically after a critical component (breaker) in the 230 KV switchyard tripped, resulting in power supply failure to the reactors.

Both reactors shut down their operations and restarted a couple of days later.

According to Kotteeswaran, the MAPS' operational licence is valid till 2014.

Every nuclear power plant in India has to renew its operational licence once in five years.

After the accident in Fukushima reactors in Japan, additional safety measures have been suggested by the Atomic Energy Regulatory Board to NPCIl for its units.

The NPCIl has also been asked for an implementation roadmap. Till such time, the units are given limited period licence.

Meanwhile NPCIl is taking a series of measures as a part of its corporate social responsibility at Kalpakkam and surrounding places like building of bus shelters, overhead water tanks, improvement in the local school laboratories.