What is the formula of DC motor?

What is the formula of DC motor?

k = N = V – IaRa / kΦ

The above relation shows that the speed of a DC motor can be controlled through change in voltage, flux and armature resistance.

What is Z in DC motor?

P – number of poles of the machine. ϕ – Flux per pole in Weber. Z – Total number of armature conductors. N – Speed of armature in revolution per minute (r.p.m).

How do you calculate the EMF of a DC motor?

EMF equation of a DC generator
1. Flux cut by one conductor in one revolution = dΦ = PΦ …. (Weber), Number of revolutions per second (speed in RPS) = N/60.

What is the basic electrical formula?


Quantity Formula Unit
Voltage V = I R Volt (V)
Current I = V R Ampere (A)
Resistance R = V I ohm ( ω )
Power P = VI Watt (W)

What is back emf formula?

The back emf is calculated based on the difference between the supplied voltage and the loss from the current through the resistance. The power from each device is calculated from one of the power formulas based on the given information. The back emf is ϵi=ϵS−I(Rf+REa)=120V−(10A)(2.0Ω)=100V.

What is the formula for armature current?

Armature Current Formula
To calculate the armature current, subtract the back e.m.f. from the source voltage, then divide by the armature resistance.

What is torque of DC motor?

In a DC motor, a circumferential force (F) at a distance r which is the radius of the armature is acted on each conductor, tending to rotate the armature. The sum of the torques due to all the armature conductors is known as armature torque (τa).

What is voltage drop formula?

Voltage drop of the circuit conductors can be determined by multiplying the current of the circuit by the total resistance of the circuit conductors: VD = I x R.

What is current formula?

Ohm’s law relates the current flowing through a conductor to the voltage V and resistance R; that is, V = IR. An alternative statement of Ohm’s law is I = V/R.

What is torque of a motor?

Torque relates to the rotational force of an electric motor while speed refers to the rate that the motor can rotate. This means that torque is associated with rotational force while speed relates to the rate of rotation which can be calculated by examining the RPMs, or revolutions per minute.

What is the eddy current?

Eddy currents are loops of electrical current induced within conductors by a changing magnetic field in the conductor according to Faraday’s law of induction. Eddy currents flow in closed loops within conductors, in planes perpendicular to the magnetic field.

What is back EMF formula?

What is the torque equation of DC motor?

Torque or moment or moment of force is the tendency of a force to rotate or move an object about an axis. A force is a push or pull, likewise, torque is a twist to an object. Mathematically, torque, T = F × r.

How do I calculate current?

The current formula is given as I = V/R. The SI unit of current is Ampere (Amp).

What are the 3 Ohm’s law?

Ohm’s Law Formulas
They are; I = V / R. V = IR. R = V / I.

What are the 3 formulas for power?

Power Formula is articulated as,

  • P = E t.
  • P = W t.
  • P = V 2 R.

How do I calculate RPM?

How to Calculate Motor RPM. To calculate RPM for an AC induction motor, you multiply the frequency in Hertz (Hz) by 60 — for the number of seconds in a minute — by two for the negative and positive pulses in a cycle. You then divide by the number of poles the motor has: (Hz x 60 x 2) / number of poles = no-load RPM.

What is maximum torque?

Maximum torque means the highest value of the net torque measured at full engine load.

What is Lenz force?

Lenz’s law states that. The induced electromotive force with different polarities induces a current whose magnetic field opposes the change in magnetic flux through the loop in order to ensure that the original flux is maintained through the loop when current flows in it.

What is hysteresis loss?

The hysteresis loss instead is the energy entrapped in magnetic materials exposed to a magnetic field in the form of residual magnetization—a typical behavior of FM materials—which is then lost as heat during the demagnetization step.

What are the 3 formulas in Ohm’s law?

3-4: A circle diagram to help in memorizing the Ohm’s Law formulas V = IR, I = V/R, and R= V/I.

What is the SI unit of ohm?

The SI unit of electric resistance is the ohm (Ω). 1 Ω = 1 V/A. When spelled out in full, unit names are treated like ordinary English nouns. Thus the names of all units start with a lower-case letter, except at the beginning of a sentence or in capitalized material such as a title.

What is the SI unit of Ohm’s law?

Ohm’s law formula is written as; V ∝ I. Therefore, V = RI where R is a constant called resistance. R depends on the dimensions of the conductor and also on the material of the conductor. Its SI unit is Ohm (Ω).

What is Ohm’s law rule?

Ohm’s Law Equation : V = IR, where V is the voltage across the conductor, I is the current flowing through the conductor and R is the resistance provided by the conductor to the flow of current.

How do we calculate torque?

To calculate load torque, multiply the force (F) by the distance away from the rotational axis, which is the radius of the pulley (r). If the mass of the load (blue box) is 20 Newtons, and the radius of the pulley is 5 cm away, then the required torque for the application is 20 N x 0.05 m = 1 Nm.