ISLAMABAD, Oct 10 (APP):The National Transmission & Despatch Company (NTDC) transmission network faced 911 tripping during peak winter season last year due to heavy fog, smog and industrial pollutions.
Out of total, 177 tripping were reported on 550kV and 734 tripping on 220kV transmission lines respectively,sources told.
On 500 kV transmission lines, the South witnessed 92 and North 85 tripping while on 220 kV transmission lines, 263 was occurred on South and 471 on North respectively during the said period, they said.
However, they said that NTDC was striving hard to enhance the reliability and availability of its transmission network to meet the performance requirements as per national and international standards.
They said various short, medium and long terms measures were being taken to overpower the tripping issues. Under short term, RTV coating and replacement of disc insulators of 500 kV Port Qasim-Jamshoro transmission line had already been completed in April besides initiating procurement for live line washing units. RTV coasted insulators on all 500 kV transmission liens near coastal belt in southern part was being installed, they said. Under medium term measures, 90 per cent auto-reclosers had been put into service on 500 kV and 220 kV transmission lines. The NTDC had also hired an international expert of insulator design through NESPAK.
The sources said NTDC has total 61 grid stations of 500 kV and 220 kV with 17,292 kilometer transmission lines across the country. Out of total, 16 grid stations were of 500 kV while 45 of 220 kV, they said.
Meanwhile, the NTDC carried out various improvement schemes during FY2018-19 to overcome constraints in its transmission networks.
They said the schemes included rehabilitation/augmentation at 500KV Port Qasim transmission line to 500 kV NKI grid station and Jamshoro circuits for evacuation of maximum power from Port Qasim Power Plant, energization of 220kV Chakdara grid station.
Augmentation of Transformer at 220 KV T.T Singh Grid Station (1×250 MVA) was completed in January and 220KV D.I Khan Grid Station was energized in February this year .
They said the Augmentation of Transformers at 220 KV Ludewala Grid Station (3×250 MVA) and Augmentation of Transformers at 220 KV Vehari Grid Station (3×250 MVA) was also carried out during March this year . 220KV Nowshera grid station, Extension Works / Addition of 750 MVA at 500 KV Rawat Grid Station and Augmentation of Transformer at 220 KV Samundri Road Grid Station (1×250 MVA) were completed during April this year .