INDUSTRAL VISIT on 13/05/2022

THE DAY OF VISIT: 13/05/2022

42 students of II-year EEE of SRM Valliammai Engineering College Students visited 400/230kV Sriperumbudur Substation on 13-05-2022. The Substation was explained briefly by Assistant Engineer Mr. M. Gopala Krishnan. This substation receives power from different power plants like Mettur Thermal Power Station, Neyveli lignite Corporation, Madras Atomic Power Station in Tamil Nādu. The power is transmitted and distributed to many places like Oragadam, Kadaperi, Padapai and to companies like Hyundai, Ford etc. The different components and its functions that we saw in 400 kV Substation are as follows:

Current transformers (CT): The lines in substations carry currents in the order of thousands of amperes. The measuring instruments are designed for low value of currents. Current transformers are connected in lines to supply measuring instruments and protective relays.

Potential transformers (PT): The lines in substations operate at high voltages. The measuring instruments are designed for low value of voltages. Potential transformers are connected in lines to supply measuring instruments and protective relays. These transformers make the low voltage instruments suitable for measurement of high voltages.

Circuit breaker (CB): Circuit breakers are used for opening or closing a circuit under normal as well as abnormal (faulty) conditions. Different types of CBs which are generally used are oil circuit breaker, air-blast circuit breaker, vacuum circuit breaker and SF6 circuit breaker.

Isolators or Isolating switches: Isolators are employed in substations to isolate a part of the system for general maintenance. Isolator switches are operated only under no load condition. They are provided on each side of every circuit breaker.

Lightning arresters (LA): Lightning arresters are the protective devices used for protection of equipment from lightning strokes. They are located at the starting of the substation and also provided near the transformer terminals.

Earth switch: It is a switch normally kept open and connected between earth and conductor. If the switch is closed it discharges the electric charge to ground, available on the uncharged line.

Wave trap: This equipment is installed in the substation for trapping the high frequency communication signals sent on the line from remote substation and diverting them to the telecom panel in the substation control room.

Coupling capacitor: A coupling capacitor is used in substations where communication is done by AC power line. It offers very low impedance to high frequency carrier signal and allows them to enter the line matching unit and blocks the low frequency signal.

Bus-bar: When number of lines operating at the same voltage levels needs to be connected electrically, bus-bars are used. Bus-bars are conductors made of copper or aluminum, with very low impedance and high current carrying capacity.

About the visit to 400/230 KV Power Corporation of India Ltd, Sriperumbudur:

On 13.05.2022 the students of II year (42 students) along with two faculties have visited the 400/230 KV Power Corporation of India Ltd. We have reached the power grid corporation at 10.20 a.m. and an Assistant Engineer started giving lectures about the entire module held in front of the office. Then students were brought to the site and were explained about each and every aspect of receiving(400KV) and distribution power (230KV and various ranges required by the customer) and converted power is distributed to the various main cities and industrial in Chennai based on their requirement.