Currently I am working on simulation model for the non-control Brushless DC motor in MATLAB/Simulink environment. BLDC parameters are from the paper via IEEE online library. For now, I am not able to understand why I have higher back-EMF voltages in each phase like the input voltage. I know, it is not easy question, because you don't see my MATLAB/Simulink model, but I can send it to you by email. For example, if the input voltage is 60V (+- 30V for each phase) then I have (+- 33-34V) back-EMF voltages for each phase.