# Torque in a 3-phase delta connected induction motor

I know the equation for torque is

        T=[m*(N2/N1)^2/2*pi*Ns]*[s*E1^2*R2/R2^2+(s*X2)^2]


N2/N1 is the effecting rotor-stator turns ratio. I have it written like 0.90:1.

How would I write it as N2/N1? Would it be 1/0.90?

• 0.90/1 = 0.90 if you put that in do you get a useful result? – Jasen May 31 '19 at 20:32
• My induction motor was 3 phase, and the torque value I got was 0.6Nm. I'm not sure if it sounds about right or not. – Sophie Jun 1 '19 at 13:52
• If I did it as 1/0.90=1.1 recurring, then I get an end value of torque=0.95Nm? – Sophie Jun 1 '19 at 14:00
• Which one sounds about right? Would be grateful if anyone could explain why which one is right? – Sophie Jun 1 '19 at 14:02
• Nothing "sound right" in this question. I would say that if the rotor-stator turns ratio is given as 0.90:1 that is 0.9 rotor turns for 1 stator turn and N2.N1 = 0.9/1. In most motor problems, the equivalent circuit is first simplified by adjusting the X2 and R2 values for N1 = N2. I can not determine how that torque equation was derived. – Charles Cowie Jun 1 '19 at 20:02

$$\0.90:1\$$ as a ratio is the equivalent of $$\ \frac{0.9}{1} = 0.9 \$$.