Why a DC series motor has a higher starting torque?
Why DC series motor produce high starting torque? The torque of the DC series motor is proportional to the square of the armature current. That is why the DC series motor has high starting torque. The DC series motor produces the highest torque among all kinds of motors.
Which DC motor gives the highest starting torque and why?
Series wound DC motors are best for applications that require high startup torque, without the need for speed regulation. Like a shunt motor, as a load is applied to a DC series motor, the motor speed decreases, which reduces the back EMF and increases the net voltage.
Why the starting torque of a DC series motor is more than that of a DC shunt motor of the same rating?
Torque(T)= (Ia)^2. Thus we observe from the above equation that, torque in DC Series Motor is directly proportional to the square of armature current and torque is directly proportional to armature current in DC shunt motor. This is the reason why DC series motor have high starting torque than DC shunt motor.
Which DC motor gives high starting torque?
DC Series motor has high starting torque. We can not start the Induction motor and Synchronous motors on load, but can not start the DC series motor without load. DC motor has high starting torque.In a series motor the same current flows through the armature and the field winding.
How do you increase the starting torque of a DC motor?
Any DC motor will experience a decrease in speed when a load is applied, which causes the back EMF to decrease. The reduction in back EMF increases the net voltage, since the supply voltage remains constant. The net voltage increase causes the armature current to increase, which increases the motor torque.
Why the starting torque is low in DC shunt motor?
The high number of turns allows a strong magnetic field to be generated, but the smaller gauge wires provide a high resistance and limit the current flowing through the shunt coil. Therefore, the starting torque of a DC shunt motor is low, meaning that the shaft load must be small at startup.
Why does Series motor start with load?
At the starting of the motor there is no back emf, so large current current flows cause high starting torque. This starting torque leads to very fast acceleration of motor if shaft is not connected to any load. This fast acceleration cause motor to damage. So series motor are always started with load.
What is stall torque in DC motor?
Stall torque is the torque available from a motor whose output rotational speed is zero. Motors in a stalled condition may be prone to overheating and possible damage if the current flowing under these conditions becomes higher than the maximum continuous rating.
What is the starting torque of a DC shunt motor?
load for a DC shunt motor. The starting torque for this motor is about 1.5 times the full-load torque (Figure 7-49). This is sufficient to start this type of motor while under full load. The shunt motor, however, has the lowest starting torque of any of the other DC motors.
Which has high starting torque?
DC Series motors have high starting torque but induction motors have wide range of speed control.