Answer / kalirajan.n

system, a prime mover drives a direct current (DC) generator
at a constant speed. The armature of the DC generator is
connected directly to the armature of a DC motor. The DC
motor drives the load equipment at an adjustable speed. The
motor speed is adjusted by adjusting the output voltage of
the generator using a rheostat to adjust the excitation
current in the field winding. The motor field current is
usually not adjusted, but the motor field is sometimes
reduced to increase the speed above the base speed. The
prime mover is usually an alternating current (AC) motor,
but a DC motor or an engine might be used instead. To
provide the DC field excitation power supply, Ward Leonard
systems usually include an exciter generator that is driven
by the prime mover.[3][

Answer / kalirajan.n

that's not ward lconard that's "WARDD LEONARD". Ward leonard
system is nothing but the combined system of Motor and
generator coupling through the MECHANICAL motive. it's very
useful metod for SPEED CONTROL PURPOE. And it's mostly USED
in RAILWAY TRACTION system.

Answer / jugs

ward leonard control is a very efficient way of speed
control in motors.in this method we vary the stator
voltage to control the speed.
most important feature of this method of speed control
is ,we can increase & decrease the speed with respect to
the base speed.

Answer / najib

Ward Leonard method is a very effective method of speed
control that allows the variation of speed both above and
below the base speed.
The speed control below the base speed is obtained by
varying the supply voltage to the armature of the motor.The
point important here is till the base speed the speed
control is constant torque and variable power method.
The speed above the base speed can be obtained by reducing
the flux of the field and it is a constant power and
variable torque method.

Answer / tapeshwar pandey

This is unidirectional speed control of dc shunt motor by
varrying the field flux.

how to calculate the knee point voltage of current transformer?

2 Answers  

---

What are the two basic types of transformers?

0 Answers  

---

what is the purpose of NGR?

25 Answers   Assam Electricals,

---

What does the letter CTNM in negative phase sequence relay means?

0 Answers  

---

How to convert resistance value at 20 degree to 90 degree?

2 Answers  

---

---

can a rotating machine give the DC output without commutator? if yes, how? if no, why?

6 Answers   BARC,

---

what will be d.g. capacity to cater together for 14hp A.C. load & 3kw lighting load

0 Answers  

---

what will be the maximum winding temperature of 6.6kv HT motor 450kw, Full load current 49A. 50Hz Frequency.

0 Answers   DVC,

---

Why transformer rating is represent in KVA?

7 Answers   Bhel, Sonalika, Usha Martin, Wipro,

---

Can we parallel two grid with different incoming voltage. Ex.let say one grid is 132kv and another is 220kv.

2 Answers  

---

The insulation resistance of a cable can be measured by

3 Answers  

---

what is the difference between squirrel cage & slip ring induction motor?

17 Answers   College School Exams Tests, NTPC, Ramyaa Electro Gear,

---