Severe pollution in north Chennai led to tripping and power cut in parts of Chennai, says report
The pollution in the north Chennai network and severe insulator tracking led to the tripping of the transmission lines, which resulted in the blackout, sources said.
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CHENNAI: The power blackout in north Chennai and parts of west and central Chennai on Friday morning was caused by severe pollution and insulator tracking, said the Southern Regional Load Despatch Centre (SRLDC) in its report.
The pollution in the north Chennai network and severe insulator tracking led to the tripping of the transmission lines, which resulted in the blackout, sources said. Insulator tracking is the phenomenon when the current flows over the surface of the insulation, which generates heat and damages the insulation.
According to the SRLDC’s flash report of outage/multiple trippings, the preliminary reason for the tripping of the lines is due to severe pollution in the North Chennai network and also due to severe Insulator tracking. This led to the overloading of the 230kV transmission lines in the North Chennai network from 1.14 pm on May 16.
“Firstly, the 230kV NCTPS Stage 1 - Tondiarpet D/C lines tripped, hence this caused overloading of 230kV Alamaty - Manali -1 (the 230kV Alamaty - Manali - 2 was already under breakdown as informed by TN, SLDC). Subsequently, the 230kV Alamaty - Manali -1 tripped on overloading, resulting in cascading tripping of the 230kV transmission system in the North Chennai area. The Core Chennai areas were affected due to the disturbance,” the report said.
Speaking to DT Next, a senior Tangedco official said that the transmission line tripping was caused by pollution. Explaining this, the official added that fly ash deposit on insulators, flue gas emission from the industries in Manali area, and moisture from sea breeze could have damaged insulators, leading to tripping.
As per the report, the duration of power interruption was 130 minutes and approximately 450 MW generation loss. The 210 MW units 1 and 2 of the North Chennai Thermal Power Station Stage I, which has three units of 210 MW capacity, tripped at 2.37 am on May 17 after the 230 kV NCTPS-Sriperumbudur line tripped. The unit-1 was revived at 12.27 am on May 18 while the unit-2 was brought back at 4.01 am on Friday itself.
Due to the non-availability of any source power supply, substations at Manali, Tondiarpet, Pulianthope, Basin Bridge, Vysarpadi, CMRL Central and TNEB Headquarters were tripped. They were revived within one hour through backfeeding from substations at Taramani, Sunguvarchatram and Alamaty, the report added.
