In the equation of torque, The rotor resistance, rotor inductive reactance and synchronous speed of induction motor remain constant. … 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.
How is torque calculated in an induction motor?
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 rated torque calculated?
- Torque (lb.in) = 63,025 x Power (HP) / Speed (RPM)
- Power (HP) = Torque (lb.in) x Speed (RPM) / 63,025.
- Torque (N.m) = 9.5488 x Power (kW) / Speed (RPM)
- Power (kW) = Torque (N.m) x Speed (RPM) / 9.5488.
How do you calculate maximum torque of an induction motor?
The developed torque is maximum when the rotor resistance per phase is equal to the rotor reactance per phase under running conditions. By putting the value of sX20 = R2 in the equation (1) we get the equation for maximum torque.
What is motor torque formula?
As you see this equation torque is the product of the force and the distance between the force and the center of rotation. For example, if you want to hold the force acting on the end of pulley, T = F x r.
What is 120 in motor speed formula?
The equation for calculating synchronous speed is: S = 120 f/P speed = constant (120) times frequency of power source (60 Hz) divided by number of poles used in the motor (P). Where does the 120 come from and what units does it have? There is RPM on one side and Cycles/second divided by #of poles on the other.
How do I calculate torque?
A practical way to calculate the magnitude of the torque is to first determine the lever arm and then multiply it times the applied force. The lever arm is the perpendicular distance from the axis of rotation to the line of action of the force. and the magnitude of the torque is τ = N m.
How much torque does a 1 hp motor have?
The 1800 RPM, 1HP motor produces 3 ft. lbs of torque at 1800 RPM. The 3600 RPM, 1HP motor produces 1.5 ft.
What is rated torque?
Rated torque is the maximum continuous torque available at the design speed that allows the motor to do the work without overheating. Starting torque is the torque the motor delivers at zero speed.
What is full load torque in induction motor?
Full-load (Rated) Torque or Braking Torque
The Full-load Torque is the torque required to produce the rated power of an electrical motor at full-load speed. In imperial units the Full-load Torque can be expressed as. T = 5252 Php / nr (1)
What is the dimensional formula for torque?
The SI unit for torque is Newton- meter as we know that the unit of force is newton which is equal to Force=mass×acceleration. The SI unit of mass is Kilogram and acceleration is meter/sec2. Hence the dimensional formula of torque is ML2T−2.
What is the starting torque?
Starting torque is the torque transferred by the shaft coupling during run-up (see Start-up process). It is calculated based on the ratio of power (P) to angular velocity (ω) and is represented as a rotational speed function.
Is torque directly proportional to RPM?
The relation between torque and speed are inversely proportional to each other. The torque of a rotating object can be mathematically written as the ratio of power and angular velocity.
Does 2 motors double torque?
A motor always provides the torque which the load requires. … When two motors are connected on a same shaft and are run at same speed, the torques would definitely add up, but the speed (rpm) won’t change.
Why electric cars have more torque?
The benefit of using an electric motor to power a car is that it can help drivers reach maximum torque from 0 RPM. This is because electric motors use an electric current, which moves through a magnetic field and creates the force necessary to rotate the armature and get the car moving.