I want to simulate an BLDC motor, so I am studying corresponding mathematical model. My problem is that I am little bit confused by the torque equation.
\$e_a\$, \$e_b\$, \$e_c\$ - Back-EMF voltages (induced components of winding voltage drop)
\$i_a\$, \$i_b\$, \$i_c\$ - currents through windings
The amplitude of back-EMF voltage is proportional to angular velocity, right? So how can torque be dependent on back-EMF voltage? One would get zero torque for zero angular velocity. I know torque should be maximum at start point, but I am missing something to understand this equation..
P.S. I would get that in stable state, so I can calculate torque from back-EMF for constant speed. But how can I calculate output torque on shaft in nonstable state? Is that the equation including torque constant (\$T=K_t.I\$)?