1 Answer

Answer :

In Ward-Leonard control the lower limit of speed is imposed by residual magnetism of the generator.

Related questions

Last Answer : The main disadvantage of the Ward-Leonard control method is high initial cost, high maintenance cost, low efficiency at light loads.

Last Answer : Ward-Leonard control is basically a voltage control method.

Last Answer : Speed control by Ward Leonard method gives uniform speed variation in both directions.

Last Answer : For constant torque drive armature voltage control speed control method is preferred.

Description : Speed control of the motor using TRIAC

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Description : The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque  (1) Decreases (2) Increases (3) Remains constant (4) None of the above

Last Answer : The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque Increases 

Last Answer : Series motor has the poorest speed control.

Last Answer : Usually wide and sensitive speed control is desired in case of colliery winders.

Last Answer : Speed control of a universal motor is achieved by varying field flux with tapped field windings, connecting rheostat in series, applying variable voltage by means of silicon controlled rectifier, applying variable voltage by means of variable auto-transformer.

Last Answer : The speed control of universal motor used for sewing machines is by varying the resistance.

Description : What are the speed control methods of dc motor?

Last Answer : Field control of DC motor Armature control of DC motor

Description : speed control methods of three phase induction motor?

Last Answer : Speed control of three phase induction motor

Description : The chief advantage of Ward-Leonard system D.C. motor speed control is that is  1. Can be used even for small motors 2. has high overall efficiency at all speeds 3. Gives smooth, sensitive and wide speed control 4. Uses a flywheel to reduce fluctuations in power demand

Last Answer : The chief advantage of Ward-Leonard system D.C. motor speed control is that is Gives smooth, sensitive and wide speed control 

Description : Why does the speed of a DC shunt motor decrease as the load increases?

Last Answer : Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease.

Description : Under constant load conditions, the speed of a d.c. motor is affected by?

Last Answer : Under constant load conditions, the speed of a d.c. motor is affected by field flux.

Last Answer : If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will increase.

Description : The method of D.C. motor speed control shown in the illustration is known as _____________. EL-0101 A. Ward-Leonard B. Sperry-Rand C. Atlas-Copco D. Burmeister-Wain

Last Answer : Answer: A

Description : The basic type of D.C. motor speed control where a generator armature directly feeds the motor armature and the motor and generator fields are excited by a separate D.C. source is called ___________________. A. Burmeister-Wain B. Ward-Leonard C. Sperry-Rand D. Atlas-Copco

Last Answer : Answer: B

Description : is an open loop control system. (a) Ward Leonard control (b) Field controlled D.C. motor (c) Stroboscope (d) Metadyne

Last Answer : Ans: B

Description : If the math was easier then could we have a speed limit on automobile acceleration?

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Last Answer : How?

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Description : What are the disadvantages of Open loop control system?

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Description : Draw and explain bulk correction method for power factor & control.

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