Question

Speed equation of DC motor is​

Answer 1

Answer:

DC Motor Speed Control Theory

To derive the speed of a DC motor, we start with the equation for the DC motor’s EMF (Electromagnetic Force). We know that the EMF equation of DC motor is equal to:

Hence rearranging the equation:

N = 60A E / PZØ

With k = PZ/60A, then:

N = E / kØ

Hence with E = V – IaRa, we derive the speed of the DC motor (N) =V-IaRa/kθ

Answer 2

k = N = V – IaRa / kΦ. From the above equation, the speed of the motor depends on supply voltage (V), Flux (Φ), and Armature resistance (Ra). Therefore, the speed of a DC motor can be varied, changed and controlled by changing; Terminal voltage “V” (AKA Applied Voltage Control Method).