How is torque calculated in an induction motor?

Contents

Torque of a three phase induction motor is proportional to flux per stator pole, rotor current and the power factor of the rotor. T ∝ ɸ I2 cosɸ2 OR T = k ɸ I2 cosɸ2 .

How is motor torque calculated?

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.

What is the torque of 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.

How do you calculate the torque of a single phase induction motor?

The above equation expresses the developed torque directly in terms of the air gap power Pg and the synchronous speed ωs. Since ωs is constant and independent of the load conditions. If the value of the Pg is known then, the developed torque can be found directly.

What is the formula of induction motor?

Slip Speed & Slip of Induction Motor:

Slip speed is the difference between synchronous speed and rotor speed; Nslip = Ns – N (Speed in RPM) ωslip = ωs – ω (Angular speed in Rad/sec)

How do you calculate torque?

Mathematically, torque can be written as T = F * r * sin(theta), and it has units of Newton-meters. When the sum of all torques acting on an object equals zero, it is in rotational equilibrium.

How does induction motor increase torque?

There are three ways to improve the starting torque of Single phase induction Motor

1. Internal Rotor Resistance. The across the line starting torque at low speed can be increased by increasing the rotor resistance. …
2. External Rotor Resistance. …
3. Variable Voltage/Frequency.

Does induction motor have high starting torque?

Slip ring induction motor has high starting torque. Because slip ring is connected through the resistance. When the supply is on the resistance is increases the phase difference is decrease due to this starting torque is increases.

What is torque of motor?

Torque is a rotating force produced by a motor’s crankshaft. The more torque the motor produces, the greater is its ability to perform work. Since torque is a vector acting in a direction it is commonly quantified by the units Nm or pound-feet.

How do you calculate maximum torque of an induction motor?

So, when slip s = R2 / X2, the torque will be maximum and this slip is called maximum slip Sm and it is defined as the ratio of rotor resistance to that of rotor reactance. NOTE: At starting S = 1, so the maximum starting torque occur when rotor resistance is equal to rotor reactance.

IT IS INTERESTING:  How long can you leave a chipped windshield?

How is induction motor efficiency measured?

The efficiency is measured by dividing the total losses by two. – Method F: Equivalent circuit calculation. This is usually the least accurate way to calculated motor efficiency because such a large portion of losses are not directly measured.

What is the efficiency of induction motor?

Ideally, there’s some slippage of the rotor relative to the frequency; typically, this is about 5%. As such, these motors are considered asynchronous motors. Efficiency of three-phase induction motors can vary from 85% to 96%.