Rotor Angles in PSSE Dynamic Simulation
Rotor Angles in PSSE Dynamic Simulation
(OP)
Hi Everyone, I have set up IEEE 39 bus system in PSSE. I am able to run the dynamics successfully. The only problem I got is the rotor angles which are increasing indefinitely when I apply a contingency. They increase upto some 100's of degrees.The speed deviations are also in the range of 1E-4. This is same with all the generators. Before applying the contingency, they are constant. Can Anyone tell me if this is an unstable behavior? Is there any better way to monitor the rotor angles? Every thing else seems to be good, the voltages and all the other values settle at constant values. Thank you






RE: Rotor Angles in PSSE Dynamic Simulation
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(2B)+(2B)' ?
RE: Rotor Angles in PSSE Dynamic Simulation
RE: Rotor Angles in PSSE Dynamic Simulation
RE: Rotor Angles in PSSE Dynamic Simulation
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(2B)+(2B)' ?
RE: Rotor Angles in PSSE Dynamic Simulation
Nevertheless, there should be a bus somewhere in the calc that is identified as a reference.
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(2B)+(2B)' ?
RE: Rotor Angles in PSSE Dynamic Simulation
The other is that your model and/or initial conditions are failing to converge. Read the manual sections related to this topic and see if there are any specific requirements, restrictions or hints on ensuring that you've actually got a valid model.
RE: Rotor Angles in PSSE Dynamic Simulation
@davidbeach, the manual says that the output which I am seeing are the relative angles. They remain at some constant values during the normal conditions, but when I apply some disturbance, they all change together. What I expect here is that they settle down at constant values determined by the new generator outputs, which is not happening.
RE: Rotor Angles in PSSE Dynamic Simulation
If it is the later, then the contingency you added will cause the testing generator OOS
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RE: Rotor Angles in PSSE Dynamic Simulation
You might want to post a plot here for some better feedback.. Basically you have a drifting angle plot described, which means you need to select a different reference, or not. The nature of the plot matters. Did you plot voltage? What does that look like? Are the plots of angle or voltage well damped? Is there "hash" on the plots? To be honest neither the absolute or relative angle value is particularly important...it is more the nature of what that angle is doing over time that matters.
RE: Rotor Angles in PSSE Dynamic Simulation
The voltages of all the generators are well damped and settle down at stable values. I found out from the tech support that the governor characteristics are responsible for continues change in angle. The angle would settle down if I used isochronous governor instead of one with droop characteristics which do not completely damp the speed deviations. I have attached a plot of rotor angles after a disturbance at 2 seconds.
RE: Rotor Angles in PSSE Dynamic Simulation