Question

Consider a sparately excited DC motor with the following parameter :

Trated = 1=Nm
Nrated =3700 RPM
Kt=0.5n−m/A (motor Torque Constant)
Kb=53 V/1000RPM( Back-EMF Constant)
Ra=0.37 ohm
La=0.15mH

Calculate the terminal voltage required to deliver a steady-state torque of 5 N-m at a speed of 1500rpm.

Answer 1

To deliver a steady-state torque of 5 N-m at a speed of 1500 RPM, the terminal voltage required is 83.5 V.

Step-by-step explanation:

To calculate the terminal voltage required to deliver a steady-state torque of 5 N-m at a speed of 1500 rpm, we need to use the motor's torque constant (Kt) and back-emf constant (Kb). First, we can calculate the current drawn by the motor at the given torque using the formula I = T/Kt, where T is the torque. Substituting the values, we get I = 5/0.5 = 10 A.

Next, we can calculate the back-emf (Eb) using the formula Eb = Kb * N, where N is the speed in RPM. Substituting the values, we get Eb = 53 * 1500/1000 = 79.5 V.

Finally, we can calculate the terminal voltage (Vt) using the formula Vt = Eb + I * Ra, where Ra is the armature resistance. Substituting the values, we get Vt = 79.5 + 10 * 0.37 = 83.5 V.