The process is straight forward. You take a written exam, HR interview, Panel Interview, and Hiring manager Interview. The written exam is basic power electronics so you should practice on that when applying to this company.
The frustrating part on this company is that they will inform you to expect a call on a certain day, give you some promising remarks on your interview but if they decided to proceed to a different candidate, they won't even inform you (paasa). Even if you request a follow-up, HR will just "seen" you and will not respond. If you get interviewed here, make sure that you don't expect anything despite good remarks.