Kodagu Power -Expert Opinion

 

Five 66 kv lines and Seven 66 kv substations serve KODAGU  District through i)Kushalnagar ii) Suntikoppa iii)  Madikeri iv)  Ponnampet and v) Virarajpet vi) Alur Siddapura vii) Shanivarasanthe substations ( about 178 Ckt kms) in addition to 4 nos  of 33/11kv stations at Somvarpet, Srimangala  Murnad and Siddapura -80 kms.

Twelve new 66 kv substations ( Eight  new & Four to upgrade 33/11KV  stations  are planned at: i)Sampaje, ii)Bhagamandala (Kopatti)   iii) Maragodu, iv) Hudikeri, v) Madapura vi) Kudige vii) Balele viii) Kodlipet. ix) Hangala Shettihalli  x) Srimangala xi) Murnad xii) Siddapura.  

KODAGU has an area of 4102 sq.kms and presently each 66 kV station covers 4102/11=410  sq.kms approximately and  after 8 new sub stations   coverage of each 66 kv sub station will be over 216 sq.kms and length of 11 kv lines  will be over 15 kms  considering zig zag factors and terrain.

My few suggestions:

 1) To make all 66 Kv SINGLE CIRCUIT lines planned, to Sampaje/ Kopatti/ Maragodu (   from Madikeri 66 kV sub-station) and Ponnampet to Hudikeri to Shrimngala as  66 Kv D.C LINES ON NARROW BASED TOWERS OR MONOPOLES WITH ‘V’ SHAPE CROSS ARMS to meet the ‘n-1’ requirement of transmission planning of CEA and to have better reliability.

2) The source to 66 kV sub-stations at Madikeri, Ponnampet and Suntikoppa are very weak and does not meet the n-1 requirement of CEA guidelines ie: if one source is down there is no alternate source.

[For example if the 66 kv tap line to Ponnampet is down  there is no way to feed the loads of South Kodagu though partial loads may be met from Madikeri  side if and when the 66 kv lines are commissioned  between Madikeri & Virajpet via Maragodu,  Murnadu  . But still bottleneck will be Kushalnagar to Madikeri 66 Kv D.C line LILO at Suntikoppa.

A 66 kV D.C line on D.C towers to be planned from Periyapatna to Ponnampet on priority basis.

3) A 66 kv D.C line to Somvarpet from Kushalnagar has to be planned in the corridor of 33 kv line and extended down to Suntikoppa, so that the load on the Kushalnagar to Madikeri D.C line comes down and existing LILO will be a back up source to Suntikoppa and  vice versa (  LILO can be made as tap lines).Even the planned 66 kv Substation at Madapura can be fed from Somvarpet DC  66 kv line.

4) It would be wonderfully good if a 220 Kv DC line is constructed from Kushalnagar to Madikeri ( KODAGU District Hqs ) as a permanent measure to meet the power requirement of Kodagu for next 2 decades in the existing corridor of 66 kV D.C line or adjacent to it using narrow based towers or monopoles with compact construction ( all 66 kV lines have to be of narrow based compact lines only in Kodagu to save corridor widths by over 30 % and save forests). This needs to be examined in detail by survey & discussions .

5) Important to use of auto reclosers ( for branch feeders) and Sectionalizers  at least 2-4 in each 11 kV lines starting with feeders which have more than 4-5 trippings per week to improve reliability of power & to localise faults. Also vegetation management along EHV & HV lines using Drones to survey tree growth & cut trees so as to reduce faults.

6) Study of reactive power management on 11 kV lines & use of capacitor banks in Sub stations or along 11KV lines so as to reduce line losses as most loads will be from agricultural loads with low power factors. Distribution engineers to be told about the importance of Economic loading of 11 KV feeders ( not loading till thermal limits) so as to reduce losses and improve voltage profile.

Kindly go through the above and if there are any comment/feedback please let me know and we can talk it out.

Vs rao

[ Er V VENKATA SUBBA RAO]

Former Director Technical BESCOM. KARNATAKA.