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Showing posts from March, 2018

What is heat rate?

Amount of heat energy needed to produce one unit of electrical energy.

STG Protections?

 Differential  Negative Phase sequence voltage fault  Negative Phase sequence current fault  Over current  frequency fault  field fault  Reverse Power  Stator Earth fault Your comments will be highly appreciated

Power factor & Reactive power?

The relationship is determined by the "power factor". This is normally supplied by the generator OEM. It's considering losses of actual power generator and power supplied.  There must also be kept in mind the grid also has losses so depending on how your power output is measured there may be more correction factors to take into consideration.  For more in-deep, for example see Wikipedia and search on "power factor. I hope this will help you.  Reactive power supplied by a generator is dependent on the requirement of the grid to which it is connected. it is absolutely proportional to the terminal voltage of the machine concerned. Otherwise it does not have any relationship with the active power generated of the concerned unit and hence no proportionality can be arrived.  With the reactive power the generator participates into maintaining grid voltage; With the active power generator participates into maintaining grid frequency. Total generator load is composed

What is the purpose of IGV in Gas Turbine?

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IGV (inlet guide vane) used to modulate the inlet air flow to compressor suction according to turbine output to maintain the exhaust temperature within the range. Must be add your comments...

What is Bleed Valve in Gas Turbine & it's purpose?

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Bleed valves are provided for gas turbine axial compressor safety from surge and stall conditions. Bleed valve when generator circuit breaker open and close with the closing of generator circuit breaker. Must be add your comments...

What is Buchholz Relay in transformer?

It is a mechanical arrangement mounted on the interconnecting pipe of main oil tank and resvoire of transformer which operate at high flow of vpour through it At low vapour flow it produce slow gas alarm and t high flow fast gas alarm Must be add your comments...

Transformer Protections?

Transformer is a device which used for step up or step down the voltage without changing frequency and power. The following protection implemented on transformer.  Differential protection  Over current with voltage blocking  Composite with voltage blocking over current protection  Leads earth fault  Earth fault protection  Start cooler  Temperature protection  Pressure release protection  Buchlez relay  Oil temperature high 95c  Coil temperature high 115c  High pressure relief device(busting disk)  Over excitation of transformer  Generator transformer differential protection Must be add your comments...

Generator Protections?

 Differential  Negative Phase sequence over current  Over voltage  Over frequency  Under voltage  Under Frequency  V/Hz  Under impedance  Excitation Trip  Inadvertant energization  Over excitation  Under excitation  Stator Ground fault  Rotor earth fault  reverse Power  GCB failure  Synchronous check device Must be write your comments.

Purge time calculation on gas turbine?

Purge times are calculated from many factors, including the air flow through the gas turbine's axial compressor during purging, air flow from zero speed to purge speed, and the volume of the exhaust--including heat recovery steam generator (HRSG; boiler); exhaust stack volume, any exhaust duct work between the turbine and HRSG and stack, etc. Some installations have a "bypass stack" that can be used when the gas turbine exhaust is not to be used to make steam. In this case the purge time is usually shorter. The accepted industry standard is to have three to five "exchanges" of air through the entire unit (axial compressor, turbine, exhaust/HRSG/stack) to ensure any combustible gases are purged before fuel/spark are admitted to the gas turbine. Some manufacturers have done some very creative things with "purging" recently because owners/operators have demanded shorter and shorter purge times. If you are having difficulty or more specific questions, we c

Difference between Mark V and Mark VIe?

Mark V and Mark VIe The Mark V was developed when IBM-compatible (Intel) PCs were just beginning to be used as operator interfaces (Human Machine Interfaces) for control systems. As such, even most graphical user interfaces were just 'point-and-click' methods of sending commands to a command-line interface--which the early PCs all used. Every command which could be done with a mouse click in early versions of MS-Windows could also be issued from the command line (DOS prompt); MS-Windows was just another method for typing commands at a command prompt. The Mark VIe uses a proprietary application called ToolboxST for all configuration issues such as you are describing. Everything like downloading, MODBUS configuration, Control Constant display and changes, sequencing modifications, logic forcing, trending, etc., is done using Menu bar selections (or hot-key sequences) from ToolboxST. (I'm sure that several functions can also be done via command-line sequences, but since most