DC Motor Characteristics
If length of conductor = L meter, field intensity = B weber per square meter (Bwb/m2) and current flowing in the conductor = i ampere, then the force experienced by the conductor will be F = iBL Newton.
F= B.L.I.Sinθ
where,
- B = flux density (in Tesla).
- L = length of conductor (in meters).
- I = current flowing in the conductor.
- Sinθ = angle between the conductor and magnetic lines of force.
DC Motor Torque Formula
Torque, also known as moment or moment of force, is the force that tends to rotate or move an object around a central axis. A force is a push or pull, similarly, torque creates twisting to an object. Mathematically, torque is given as T = F × r. For DC Motor, the torque is given as
T = (0.159PΦNZ/A)Ia
where,
- T is Torque of Armature
- Ia is the armature current
- P is Number of Poles
- Ф is Flux per pole
- N is Speed of motor in (RPM)
- Z is Number of conductors
- A is Number of parallel paths
DC Motor EMF Equation
EMF or the electromotive force is responsible for flow of current in the electrical appliances. EMF is not an force but the electric potential. In case of DC Motor, a back EMF is produced which counters the armature current. The direction of this back EMF is given by Lenz Law. The formula of back emf is given as
Eb = PΦNZ/60A
where,
- P is Number of Poles
- Ф is Flux per pole
- N is Speed of motor in (RPM)
- Z is Number of conductors
- A is Number of parallel paths
DC Motor Speed
The formula for DC Motor speed is given as:
N = KEb/Φ
where,
- N is speed in RPM
- K is constant proportionality which is equal to 60A/ZP
DC Motor
DC motor is a machine that converts electrical energy of direct current into mechanical energy. In a DC motor, the input electrical energy is direct current which is converted into mechanical rotation.
In this article, we will learn what is DC motor, its Diagram, Construction, Working, types, and applications. We will also compare DC and AC Motors based on various parameters.
Table of Content
- What is DC Motor?
- Construction of DC Motor
- DC Motor Working Principle
- DC Motor Characteristics
- Types of DC Motors
- AC and DC Motors
- Applications of DC Motor