Primary response generation change

asked 2018-05-24 07:35:19 -0500

Anonymous

updated 2018-05-24 08:59:41 -0500

Hey there!

I am attempting to calculate the change of generation due to primary response so I may calculate the frequency bias in my model. It does not work.

What I have tried: - Read generation by using psspy.agenbusreal with input "PGEN" prior to simulation of fault. Run simulation till steady-state. Read PGEN for all generators again, which should now be different due to primary response. PROBLEM: the generation is the exact same!

Plots show PMECH increasing (due to primary response), and at steady-state PGEN (which I read as PELEC) should be the same as PMECH, right? What am I missing?

Additional question: Is MBASE in any way related to PMAX?

Thank you!

answered 2018-05-25 04:38:07 -0500

perolofl

2947 ●1 ●8 ●16

PGEN is used only for load flow and not in dynamics, so that variabel is not updated during a dynamic simulation. The actual generator electric power is stored in PELEC so you have to enter channels for all generators to be supervised.

At steady state with constant frequency PMECH and PELEC will be the same, if RSORCE is zero, i.e. no losses in the generator. However PELEC is given in pu system base and not in Mbase. The frequency bias for the governor may be calculated from the change in PMECH (or PELEC) during the simulation.

You can use channels with subsystem power totals for all buses (CHSB) if you are only interested in the total electric generator power (sum of PELEC) and not the individual power for each generator.

Mbase is the nominal MVA rating for the generator and the power base for all dynamic data. PMAX is a load flow parameter only and not used in dynamics.

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Hi: If the Pmax is not used in dynamics. How limitated the power generation of your plant? I already simulated a fail, but the generator inyected more power that i want. How could limitated that?