i am working in power plant in the power generation department especially Gas turbine.

our Gas turbines are MS-7001E. My question is about what are the load restrictions of Gas turbine. For example,if any gas turbine carries 40 MW and I want to increase the load to the base load but it is showing that the exhaust temperature reaches the control temp by means it doesn't accept loading.

 

MS-7001E units are usually nominally rated for about 70-80 MW, which is Base Load, exhaust temperature control. In a hot and/or humid environment that rating can decrease to less than 70 MW because of ambient conditions (high air temperature, high humidity, high elevation, etc.).

But, for a MS7001E to reach exhaust temperature control at 40 MW means that something is amiss.

The usual question is: When did this problem start?

How long since the last maintenance outage?

What is the pressure drop across the turbine inlet air filter?

Is the unit operating in simple- or combined cycle when this happens?

Are there high exhaust temperature spreads? What are the values of TTXSP1, TTXSP2, and TTXSP3 when this happens?

What fuel is the unit being operated on?

What is the FSR when this happens?

What is the CPD when this happens?

What is the exhaust temperature (TTXM) when this happens?

What is the ambient temperature (CTIM) when this happens?

What have you done to troubleshoot the problem?

[NOTE: The above signal names are typical signals names for the parameters being asked for in a Speedtronic turbine control panel. If the unit does not have a Speedtronic panel, you should still be able to find the requested information.]

 

I forgot to ask what the exhaust temperature reference values are when this occurs. What is the value of TTRXP?

What is the value of TTRXS?

What is the value of TTRX?

 

Even though you probably will have this data the frame 70001EA has the following specifications in ISO conditions
<pre>
Model Fuel ISO Base Heat Heat Exhaust Exhaust Exhaust Exhaust Pressure
Rating Rate Rate Flow Flow Temp Temp Ratio
(kW) (Btu/kWh) (kJ/kWh) (lb/hr) (kg/hr) (degrees F) (degrees C)
x10-3 x10-3
PG7121 (EA) Gas 84,360. 10,480. 11,054 2361. 1070 998. 536 12.7
Dist. 87,220. 10,950. 11,550 2413. 1093 993. 537 12.9</pre>

Depending on your site conditions , ambient temperature , humidity altitude and such the frame 7 machine you have will have a reduced Rating in all these parameters. Please post them here along with the historical data when the the machine load was normal and the parameters which you now have. along with these please post the historical data for the following tags in the system. both for when the load was normal and now at the reduced load condition.

1. Dwatt ( machine output)
2. CPD (compressor discharge pressure)
3. FSR (fuel stroke reference)
4. FQLM (Fuel input)
6. CSGV (IGV opening)
7. CTIM (compressor inlet temperature)
8. CTD (compressor discharge temperature)
9. TTXM ( exhaust temperature)
10 TTXspl1 ( exhaust spread)
11. whole wheel space probes

ok , now to the guessing part , such reduction in output of the machine is caused mainly due to a severe reduction in the compressor performance, as i mentioned above check the CDP when the machine was running with a normal load and now. if it is low , this means that your compressor is fouled and you need to do a waterwash. online water wash as i have seen does not bring a great change , you might need to go for a offline water wash in this case , if the problem is with the reduced compressor output.

another area is a bad combustion liner but most probably if this happens it will be accompanied by a high exhaust spread , mostly leading to a machine trip.

 

see please this happen on month ago and UCS control can n't save the data only for 2 weeks.
but the most important thing that i need is what are the parameters should maintained.