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Is it Possible to Select ISO on Liquid Fuel
How much is loading rate for frame 9 heavy duty on iso mode

How much is loading rate if:

Turbine is frame 9 heavy duty
Fuel is liquid
Mode is isochronus

>How much is loading rate if:
>
>Turbine is frame 9 heavy duty
>Fuel is liquid
>Mode is isochronus

Okay; the body of the post doesn't really seem to match the title which doesn't seem to match the summary....

Unless there's something unusual about the configuration of the turbine control system, it should be capable of operation in Isochronous Mode when liquid fuel is selected. (That's presuming the other fuel isn't crude/heavy or something like that.)

The 'loading rate' for Isochronous Mode is FAST. As fast as the fuel control valve can change the fuel flow-rate the unit will change load in response to the load on the system the turbine is connected to.

It's a myth that operators can control the load on a unit running in Isochronous Mode--they can't. The turbine control system senses a change in the load being supplied by the unit (a change in the number of lights, motors, the load on the motors, the number of televisions, and computers and computer monitors, etc.) which immediately tries to change the speed of the turbine and generator. As soon as the turbine control system sees the speed change--WHAM! it changes the fuel in an attempt to keep the speed, and the frequency, stable.

If the load on the system being supplied by the turbine-generator (I'm presuming one turbine-generator only) is, let's say, 60 MW, the turbine generator has to produce 60 MW in order to maintain the frequency. If an operator tries to increase the load, or decrease the load, from the turbine control operator interface all that's going to happen is the frequency of the system will change. The operator can't change the number of lights and motors, nor the load on the motors, nor the number of televisions, computers and computer monitors. In Isochronous Mode, all the operator can do is change the frequency setpoint. Period. Full stop. End of discussion.

Changing the frequency setpoint won't change the load, but it WILL change the speed of the turbine-generator, and hence the frequency of the output of the generator.

Even if there was two or three or five generators all synchronized together on a distribution system supplying load if one of the units is operating in Isochronous Mode and producing, say, 50% of rated power, the operator CANNOT change the load of the Isochronous unit with the control system of the Isochronous unit. To change the load on the Isochronous unit, the operator has to change load on one of the other units the Isochronous unit is synchronized with. For example, if it was desired to change the load on the Isochronous unit by 25% of rated (decrease the load on the Isochronous unit), an operator would have to use the turbine control system of one of the other units the Isochronous unit is synchronized with and increase the load of that unit by an amount equal to 25% of the rating of the Isochronous unit.

But, the loading rate of a unit in Isochronous Speed Control Mode is usually very fast--it has to be fast in order to respond to changes in load (the number of lights, motors, the loads on the motors, the number of televisions and computers and computer monitors). An operator can't change the power output of the Isochronous unit when it's supplying a system of lights and motors and televisions and computers and computer monitors because by selecting Isochronous Mode the operator has commanded the turbine control system to maintain frequency as load (the number of lights, motors, the loads on the motors, televisions, computers and computer monitors) changes. In order to control frequency, it has to be "free" to respond to load changes which would tend to change the speed of the unit--but it was commanded to maintain speed/frequency when it was put in Isochronous Speed Control Mode--and it's going to do that (maintain speed and frequency) while supplying the load (as long as the load doesn't exceed the rating of the Isochronous unit's prime mover (turbine in this case)). And the turbine control system is going to try to maintain frequency as tightly as it can, and change fuel flow-rate as quickly as it can.


Hope this helps!

>How much is loading rate if:
>
>Turbine is frame 9 heavy duty
>Fuel is liquid
>Mode is isochronus

Okay; the body of the post doesn't really seem to match the title which doesn't seem to match the summary....

Unless there's something unusual about the configuration of the turbine control system, it should be capable of operation in Isochronous Mode when liquid fuel is selected. (That's presuming the other fuel isn't crude/heavy or something like that.)

The 'loading rate' for Isochronous Mode is FAST. As fast as the fuel control valve can change the fuel flow-rate the unit will change load in response to the load on the system the turbine is connected to.

It's a myth that operators can control the load on a unit running in Isochronous Mode--they can't. The turbine control system senses a change in the load being supplied by the unit (a change in the number of lights, motors, the load on the motors, the number of televisions, and computers and computer monitors, etc.) which immediately tries to change the speed of the turbine and generator. As soon as the turbine control system sees the speed change--WHAM! it changes the fuel in an attempt to keep the speed, and the frequency, stable.

If the load on the system being supplied by the turbine-generator (I'm presuming one turbine-generator only) is, let's say, 60 MW, the turbine generator has to produce 60 MW in order to maintain the frequency. If an operator tries to increase the load, or decrease the load, from the turbine control operator interface all that's going to happen is the frequency of the system will change. The operator can't change the number of lights and motors, nor the load on the motors, nor the number of televisions, computers and computer monitors. In Isochronous Mode, all the operator can do is change the frequency setpoint. Period. Full stop. End of discussion.

Changing the frequency setpoint won't change the load, but it WILL change the speed of the turbine-generator, and hence the frequency of the output of the generator.

Even if there was two or three or five generators all synchronized together on a distribution system supplying load if one of the units is operating in Isochronous Mode and producing, say, 50% of rated power, the operator CANNOT change the load of the Isochronous unit with the control system of the Isochronous unit. To change the load on the Isochronous unit, the operator has to change load on one of the other units the Isochronous unit is synchronized with. For example, if it was desired to change the load on the Isochronous unit by 25% of rated (decrease the load on the Isochronous unit), an operator would have to use the turbine control system of one of the other units the Isochronous unit is synchronized with and increase the load of that unit by an amount equal to 25% of the rating of the Isochronous unit.

But, the loading rate of a unit in Isochronous Speed Control Mode is usually very fast--it has to be fast in order to respond to changes in load (the number of lights, motors, the loads on the motors, the number of televisions and computers and computer monitors). An operator can't change the power output of the Isochronous unit when it's supplying a system of lights and motors and televisions and computers and computer monitors because by selecting Isochronous Mode the operator has commanded the turbine control system to maintain frequency as load (the number of lights, motors, the loads on the motors, televisions, computers and computer monitors) changes. In order to control frequency, it has to be "free" to respond to load changes which would tend to change the speed of the unit--but it was commanded to maintain speed/frequency when it was put in Isochronous Speed Control Mode--and it's going to do that (maintain speed and frequency) while supplying the load (as long as the load doesn't exceed the rating of the Isochronous unit's prime mover (turbine in this case)). And the turbine control system is going to try to maintain frequency as tightly as it can, and change fuel flow-rate as quickly as it can.

Hope this helps!