Synchronous machine saturation instabilities
2 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
Simulating the synchronous machine below, i am unable to model saturation without immediately creating a numerical instability. The data has been sourced from factory tests, and manufacturer calculated datasheet values where tests were not possible. Decreasing sample time from 25µs to 0.25µs improves stability, but creates unacceptable simulation times.
Characteristics of the data that i am aware of:
- OC saturation curve (from test data) does not intersect the declared 1pu operating point for excitation current @ nominal volts. Scaling the saturation data to fit (1,1) has not helped.
- X''d & X''q are more different (compared to each other) than anticipated
- Increasing the parasitic load on the machine from 5-15% improves stability, but then offsets the true operating point for the rest of the model.
SM.Rating.S = 1938e3;
SM.Rating.Vline = 690;
SM.Rating.F = 60;
SM.Rating.Poles = 4;
SM.Mech.gensetH = 0.8516;
SM.Imped_Std.Ra = 0.0054; %Stator resistance @ 75degC [pu]
SM.Imped_Std.Xdst_RI = 13.7e-2; %X"d unsat pu
SM.Imped_Std.Xdt_RI = 21.9e-2; %X'd unsat pu
SM.Imped_Std.Xd_RI = 222e-2; %Xd unsat pu
SM.Imped_Std.Xqst_RI = 18.4e-2; %X"q unsat pu
SM.Imped_Std.Xq_RI = 113e-2; %Xq unsat pu
SM.Imped_Std.X1 = 6.6e-2; %Stator winding leakage reactance pu
SM.TimeConsts.Tdst_RI = 0.017; %T"d
SM.TimeConsts.Tdt_RI = 0.267; %T'd
SM.TimeConsts.Tqst_RI = 0.018; %T"q
SM.base.Iexc = 0.85;
SM.SatData.If_OC_ST = [0.19 0.35 0.55 0.6 0.67 .72 .8 .89 .92 .98 1.09 1.31 1.61 2.52]/SM.base.Iexc;
SM.SatData.V_OC = [259 374 553 586 621 659 689 716 724 742 760 793 828 897]/SM.Rating.Vline;
My first post; so please advise if i can compose my questions better! Thanks
0 Commenti
Risposte (1)
Meme Young
il 7 Giu 2020
Hi Dude I am doing sync machine modelling as well. It seems that you are imitating the simulink sync machine model. How do you use these parameters in Simulink?
5 Commenti
Meme Young
il 9 Giu 2020
Yes, thank you, I am trying to describe the difference between
Synchronous Machine pu Fundamental block
and
Synchronous Machine pu Standard block.
I am just trying to find a way to create 2 Synchronous machines, one is pu fundemental and the other is pu standard, and they have identical transient and steady-state characteristics. That means I need to find a way to convert parameters between pu standard and pu fundemental, but no documentation of matlab mentioned the exact way. The references of matlab documentation is also very confusing and chaotic, and the parameters and circuits in these references may not be suitable for matlab sync machine models at all. I am wondering if you could figure it out.
Regards
Young
Adrián Solís Bajo
il 22 Feb 2024
Modificato: Adrián Solís Bajo
il 23 Feb 2024
The methodology for the exact conversion of synchronous machine parameters from standard form to fundamental form was first described by I. M. Canay. You can find it in his article: DETERMINATION OF SYNCHRONOUS MACHINE MODEL PARAMETERS FROM THE CHARACTERISTIC QUANTITIES APPLICABLE ALSO TO SUB-SUBTRANSIENT DATA. You can also find the conversion process in the user help documentation of several power system simulation programs.
Vedere anche
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!