Contents
What is torque in an induction motor?
Torque is the turning force through a radius – with the units Nm in the SI-system and the units lb ft in the imperial system. The torque developed by an asynchronous induction motor varies when the motor accelerates from zero to maximum operating speed.
What is torque in physics definition?
Torque is a measure of how much a force acting on an object causes that object to rotate. In other words, torque is the cross product between the distance vector (the distance from the pivot point to the point where force is applied) and the force vector, ‘a’ being the angle between r and F.
An induction motor typically runs at a little below synchronous speed. The amount it runs slow is called the ‘slip’. For small values of slip, the current it draws is proportional to the slip, and to the voltage. This means the torque, which depends on current, is proportional to slip at constant voltage.
How is torque related to current and power?
The torque is the product of the flux and the torque-producing current, i.e. the component of current which is in phase with the voltage. In DC motors and AC induction motors, the magnetising current is usually constant regardless of torque, unless a special energy-saving control is applied at reduced torque.
How does voltage affect the rotor speed of an induction motor?
When the motor is loaded the rotor speed drops and induces more voltage in the rotor that will produce more rotor current to increase the torque produced to counter act the mechanical load torque. When the voltage drops the rotor speed will decrease because the electrical torque produced is proportional to the square of the voltage.
In induction motor, Torque is proportional to square of applied stator voltage (I agree that) but some source says torque is proportional to current.