TSGENCO AE case studies

TSGENCO AE · Put your knowledge to work in context.

The TSGENCO Assistant Engineer (AE) recruitment exam is the screening gate used by the Telangana Power Generation Corporation to shortlist graduate engineers for assistant engineer posts in its generating stations and corporate offices. It is aimed at candidates with a B.E./B.Tech (or equivalent) in Electrical, Mechanical, or Civil Engineering who want a state-sector generation utility role rather than a transmission or distribution one. The TSGENCO AE case studies are 5 cases and about 4,364 words.

33 kV Feeder with Poor Tail-End Voltage, a Harmonic-Rich Load and a Capacitor Bank That Keeps Blowing Fuses

A 132/33 kV substation in Telangana feeds a 22 km radial 33 kV feeder supplying an industrial cluster. Conductor data are R = 0.35 ohm/km and X = 0.45 ohm/km per phase.

938 words, about 5 min 2

Direct-On-Line Starting of a 1250 kW Boiler Feed Pump Motor on a Weak 6.6 kV Board

A 1250 kW, 6.6 kV, 6-pole, 50 Hz squirrel-cage motor drives the boiler feed pump of a 2 x 210 MW station. It is started direct-on-line from the 6.6 kV unit board, which is fed by a 6.3 MVA, 33/6.6 kV transformer of 8% impedance; the 33 kV bus behind it has a fault level of 80 MVA.

708 words, about 4 min 3

Motor Winding Failures and Nuisance Trips on a 250 kW PWM Drive with a Long Cable and a Nearby Capacitor Bank

A 415 V, 250 kW, 4-pole cage motor on a rolling mill is fed by a 6-pulse PWM voltage-source drive with a diode front end, default 4 kHz carrier and a 400 V output. The motor is 240 m away, connected by three single-core 95 mm2 cables in trefoil; the drive has no output reactor.

922 words, about 5 min 4

Diagnosing a 210 MW Unit: Rising Back Pressure versus Air-Preheater Leakage, and the Cost of Waiting

A 210 MW coal-fired unit (design turbine heat rate 1950 kcal/kWh, boiler efficiency 87.5%, auxiliary consumption 9.5%, coal GCV 3800 kcal/kg) has drifted over one month. At a steady 200 MW the condenser back pressure has risen from 0.09 to 0.12 bar absolute while the circulating-water inlet temperature stayed at 32 degC; the CW outlet rose from 38 to 41 degC at unchanged flow.

904 words, about 5 min 5

Merit-Order Dispatch for a 1000 MW Evening Peak with a Must-Run Unit and a Costly Exchange Offer

A Telangana discom control room must meet a 1000 MW evening demand from its own units. The dispatch desk holds the following data, all at the sending end of the station: Unit Capacity Auxiliary Heat rate at 100% Heat rate at 75% Coal GCV Landed coal --- --- --- --- --- --- --- A 600 MW supercritical 6.5% 2280 kcal/kWh 2340 kcal/kWh 3600 kcal/kg Rs 4200/t B 500 MW supercritical 7.0% 2320 kcal/kWh 2380 kcal/kWh 3500 kcal/kg Rs 3800/t C 210 MW subcritical 9.5% 2500 kcal/kWh 2620 kcal/kWh 3900 kcal/kg Rs 4600/t Unit C is running at 120 MW because its 220 kV corridor is required for voltage support, and its technical minimum is 55%.

892 words, about 4 min