Combined cycled power plant
3 sets of GE LM6000 PC( 43MW)
one 36MW STG by Bharat Heavy Electricals Limited
Year commissioned 1999
Main fuel Naphtha and start up fuel is HSD( high speed diesel)
Electricity is generated at 11 KV and stepped up to 110 KV before sending to the grid. Generators of the Gas Turbine are of GE,USA make and the Generator of Steam Turbine is of BHEL ,India make. Both GTG and STG generators are having brushless excitation system. Generator transformers are of TELK, India make. The 110 KV switchyard through which plant is connected to the grid comprises of 11 bays and two buses .
Advantages of the plant
1. The 165 MW Plant consists of three small gas turbines each of 43.5 MW capacity and a Steam turbine . Gas Turbines can be started and loaded in 15 minutes.
2. Plant can be operated both in open and combined cycle modes
.3. Gas turbine inlet air chillers ensure a constant power output irrespective of varying ambient conditions.
4. The small size of the gas turbines and modular design offers enhanced Operational flexibility to adjust to demand variation
quickly. The modular design of the engine makes it convenient for fast thereby increasing the availability of the plant.
5. LM 6000 Engines are one of the most efficient engines globally for open cycle operation with a gross Heat Rate of 2229 KCal/ KWH on LHV or an open cycle efficiency of 38.5%..
6. The Combined cycle Net Heat Rate (after deducting plant auxiliary load) of the plant using Naphtha is 1818 KCal/ KWH, LHV which is equivalent to an efficiency of .47.3%.
7. Possibility of using lease engines while the gas turbines are under maintenance
8. Down time required for maintenance is minimal.
9. No penalty for start /stop because of the light weight construction of the gas turbines and hence maintenance is based on Fired Engine Hours (FEH) rather than Equivalent Operating Hours (EOH) basis in the case of Heavy Duty industrial gas turbines. 10. Gas Turbines can be erected in about 6 months time.
The plant was last operated in May /June 2017 continuously for about three weeks. and without any issues.
Since stoppage of the plant ,equipment are kept in preservation mode
All the major electrical equipment have space heaters in service
Gas turbines along with the electrical generators are cranked at high speed once a month Hot air blowers are used to keep the turbine enclosures warm.
Steam turbine along with the generator is put on barring once a month. Condenser is preserved dry.
All other rotary equipment like chillers, pumps and compressors are run once a month Wherever trial run of rotary equipments are not possible ,they are hand rotated to avoid any possible sagging.
Internals of HSRG pressure parts are preserved wet using DeMineralized water treated with Hydrazene,concentration of which is maintained above 100 ppm. Hot gas path of HRSG is preserved by keeping the guillotine damper damper closed and outlet of the chimneys capped , thereby restricting free draft.
Bore scope inspection of LM6000 Engine is carried out every 4000 FEH (Fired Engine Hours).
For Engines operating on liquid fuel the HSIR (Hot Section Inspection and Replacement) is carried out every 12,500 FEH. In this the process the Combustor and the High Pressure Turbine (HPTR) is refurbished / replaced.
In case of Gas operation the HSIR is done once in 25,000 FEH
Engine Major Overhaul (MOH) is carried out once in 50,000 FEH. Since the average Fired Engine Hours are in the range of 35000 Hrs , none of the gas turbines are due for major overhaul.
Overhauling of the turbines till date were carried by Original Equipment Manufacturer only .
Dates of Hot section Fired hours since Total fired hours
replacement/overhaul/ last section replacement/ since new
GTG-1 04/07/2004,19/05/2010 5234 30814
GTG-2 01/06/2004,28/07/2009 8151 35381
GTG-3 11/07/2007,23-06/2011 4984 32031
STG 16-10-2009 8383 35882
Please contact me for more details
101-802 , Bundangro 190
Seongnam city, Kyonggido