MARK V convert to combined cycle


Thread Starter

Javier Schanck

I have a GE Frame 6B gas turbine with Speedtronic Mark V control system in simple cycle. In the conversion process to combined cycle, I need know the necesary change in the Mark V control system for operation in the combined cycle.

Can you help me with any information (or link) about the change in the control logic in Mark V?

jschanck2001 @
Very simply, when an HRSG is added to the exhaust of a gas turbine the back-pressure on the exhaust will increase, even it's only by a few cm of water. This increased back pressure will reduce output if nothing is done.

If you want to achieve maximum output at Base Load, the exhaust temperature control curves should be re-calculated.

Also, if you want to use IGV Temperature Control to maximize exhaust temperature during Part Load operation and the Mark V isn't programmed for that, it would have to be modified.

You should consult with a firm or individual knowledgeable in the determination of gas turbine operating conditions and modifications for help with such calculations and sequencing modifications.