Bombardier ALP-46 MITRAC GTO-VVVF Traction Motor Analysis - Inductor Simulation

Note: This is not an actual inductor recording, so some parts may are subject to be inaccurate.

[@GamerRobYT]

question, what's the difference between DSC and asynchronous?

[@tractioninverter]

DSC (Direct Self Control) is a method of directly controlling stator flux by applying the corresponding space vectors (switching states of the inverter) at the right time. Since this is not happening periodically, it sounds a bit "random" to the ear. This method is not based on any specific carrier frequency to generate pulses, instead it calculates the right timings in real-time (as mentioned -> this leads to "random" noise). Although the switching happens at calculated times, there is still a limit to how small or big pulses can be, which is called the tolerance band. (you could call it a specified bandwidth or a range of allowed frequencies) Asynchronous modulation, however is based on a carrier frequency - which can be a sawtooth "edge-aligned" or a triangle "center-aligned" signal. This frequency can be selected freely at any given time, as long as it's not too high for the inverter switches (few kHz for IGBT, only a few hundred Hz for GTO, and tens of kHz for MOSFET, ...) and not too low (less than 10 Pulses per half-wave). It can also be modulated randomly in a given range which is called RCFM (Random Carrier Frequency Modulation) or periodically PCFM (Periodic Carrier Frequency Modulation). Here is an actual real-life recording of DSC on a TRAXX locomotive. kzbin.info/www/bejne/lWSydZdqYtJ8kLs

[@GamerRobYT]

@@tractioninverter Thanks for the explanation

[@winstonpx]

@@tractioninverter I've always wanted to learn about traction motors in trains, are there any resources/websites/books/etc. that you recommend for learning about these? Is this something you can learn by getting an electrical engineering degree? How did you learn all of this in your experience? Thank you sm in advance!

[@tractioninverter]

@@winstonpx I can recommend the book "Electric Traction - Motive Power and Energy Supply" by Andreas Steimel. It's really informative! Hope you can learn something from it! :) And yes, studying in this field will get you the knowledge, however the really interesting stuff is company internal know-how.

[@winstonpx]

@@tractioninverter thanks for the suggestion! I've also joined the vvvf discord in case I've got any questions.

[@TheSearleFamily123]

This is what you need to record the sound: kzbin.infoUgkxj3MqV8zvRxibqXoT6oq3jEfRjmmfaT7D (both coils have inductance of 100mH)

[@ctslrailfan2696]

that’s my plan. only issue is i don’t have access to locomotives like this.

[@TheSearleFamily123]

@@ctslrailfan2696 Yeah, unfortunately you're not like Traktionsstromrichter, who [private information]

[@ctslrailfan2696]

@@TheSearleFamily123 eh, i could get access if i ask some of my buddies, but i'd rather not in my current position.

[@nooxis2643]

@@ctslrailfan2696 Do you think it would be possible to ask for a pic of the traction converter nameplate in the 46 and 46A? I'm trying to find imformations about it, but i can't find anything and I really want to know