Does the speed of a shunt motor increases or decreases when the armature current increases?
From the equation. (3) we can say, speed is inversely proportional to armature current. Thus, when the speed of the dc motor is increased, the armature current will decrease.
How does the speed of a DC shunt motor vary with armature voltage and field current?
In the armature control method, the speed of the DC motor is directly proportional to the back emf (Eb) and Eb = V- IaRa. When supply voltage (V) and armature resistance Ra are kept constant, the Speed is directly proportional to armature current (Ia). The motor back EMF (Eb) and Speed of the motor can be changed.
How will the speed of the motor change with increasing the value of armature voltage?
Very simple, with constant Field flux a DC motors speed is directly proportional to the applied DC voltage on the armature. If a DC motor is turning at a given rpm and voltage and the voltage is increased, it produces a difference between the applied voltage and the back end or voltage generated by the motor.
How can I increase the speed of my 12V DC fan?
The correct answer is use a bigger fan of same 12V rating which draws more current. However, if fan can not be changed but a slightly higher cooling is desired then you can try feeding 13 V power supply to a 12 V fan. Mostly it would run at a slightly higher speed.
How to control the speed of a DC shunt motor?
Speed Control of DC shunt motor 1.Field control methods Weakening of field causes increase in the speed of a motor and strengthening of field reduces the speed.Speed adjustment can be obtained by: Field-rheostat control involving the variation of flux by means of a field rheostat.
Where does a shunt wound DC motor fall?
The shunt wound DC motor falls under the category of self excited DC motors, where the field windings are shunted to, or are connected in parallel to the armature winding of the motor, as its name is suggestive of.
How is the speed control of a DC motor achieved?
Field Flux Control Method of DC Motor. Flux is produced by the field current. Thus, the speed control by this method is achieved by control of the field current. Shunt Motor. In a Shunt Motor, the variable resistor R C is connected in series with the shunt field windings as shown in the figure below. This resistor R C is known as a Shunt Field
Why does armature current increase in a DC motor?
The armature current will increase when the torque is demanded from the load side. This is because when the load torque increase, the speed falls down. The reduction in the speed leads to decrease of back EMF. The decrease of back EMF will lead more armature current. Ausaf Ahmad, Tinkering with electronics since a toddler !