I have parameters of 2 MW induction generator, but I need the parameters of a smaller rating, like 1 MW, 500kW, 100kW, 10kW. Is there away to calculate that?
The parameters of any machine depend on many factors including the designer. The same machine having the same name-plate data can have different parameters if designed in different factories. However,,as a very rough approximation,you can consider that the rotor active resistance (and roughly the other parameters)is inversely proportional to the machine rated power,provided that the supply voltage and the rated speed are the same. Therefore,the parameters of the 1 MW machine will very roughly double the corresponding parameters of the 2 MW induction machine.
Dear Dr Ahmed,I see from your publications that Dr Mazen was a co-other.I know him and I think he still remembers me. Please convey to him my best regards. I am surprised that you have some publications on Aircraft a,c power systems,I had some intersections with this issue in the early sixties when I was preparing of my Thesis in MOSCOW ENERGY INSTITUTE..Wish you good luck in your career.
Dear Professor Mahmoud, thank you very much for your contact. Actually Prof. Mazen Abdel-Salam was my supervisor for final year project, Master and PhD. My Master was about electrostatic precipitation (High Voltage), and my PhD was a joint research (channel scholarship) between my university and University of Texas at Tyler, TX, USA and I got it on 2010. Now, I have one MSc student working in the aircraft actuation system and at the same time I'm a researcher in STDF project about distribution generation in power system. This makes me to go to renewable energy sources, like fuel cell, wind, PV and battery systems. I will convey your regards to Dr Mazen, insha-Allah. I'm happy to know you and sorry for my long reply...
One way to avoid this is to use the per unit (PU) system.The PU values do not differ as greatly as the actual parameters in amps, volts, resistance etc. You will find there is not much variation in the PU parameters.
Dear Prof. G. Diana, thank you for your reply. Do you mean if I convert the 2MW parameters into pu, I can use these values for a new base of 1MW machine? the same for smaller ratings of 0.5, 0.1 MW ? without looking to speed or voltages?
Yes, as the PU parameters do not vary much in terms of the physical size of the machine. This is the benefit of using the PU system which is used widely in power systems. If you simply change your base power the results should be fairly reflective of larger and / or smaller systems. The PU system was used on old analogue computers which allowed machines of any size to be modelled and simulated using OP amps with a +- 15 V supply. For example 1 pu speed may be 3000/1500/1000/750 rpm and 1 pu current may be 10/100/1000A depending upon the base you choose. Since 1 pu is 100% it may represent anything depending upon base quantities.
Thanks so much Prof. Bienkowski for your answer, do you have a reference for this machine. I need xl xm, rs rr and other parameters for simulation purposes.