# D.C Machines · Electrical Machines · GATE EE

Start Practice## Marks 1

GATE EE 2022

A 280 V, separately excited DC motor with armature resistance of 1 $$\Omega$$ and constant field excitation drives a load. The load torque is proporti...

GATE EE 2018

A separately excited dc motor has an armature resistance R$$a$$ = 0.05Ω. The field excitation
is kept constant. At an armature voltage of 100 V, the ...

GATE EE 2016 Set 1

A 4-pole, lap-connected, separately excited dc motor is drawing a steady current of 40 A while
running at 600 rpm. A good approximation for the wavesh...

GATE EE 2015 Set 2

A 4-pole, separately excited, wave wound DC machine with negligible armature resistance is rated for 230 V and 5 kW at a speed of 1200 rpm. If the sam...

GATE EE 2015 Set 2

A shunt-connected DC motor operates at its rated terminal voltage. Its no-load speed is 200 radian/second. At its rated torque of 500 Nm, its speed is...

GATE EE 2015 Set 1

A separately excited DC generator has an armature resistance of 0.1 $$\Omega$$ and negligible armature inductance. At rated field current and rated ro...

GATE EE 2014 Set 3

The no-load speed of a 230 V separately excited dc motor is 1400 rpm. The armature
resistance drop and the brush drop are neglected. The field current...

GATE EE 2011

A 4–point starter is used to start and control the speed of a

GATE EE 2007

The dc motor, which can provide zero speed regulation at full load without any controller is

GATE EE 2006

In a $$DC$$ machine, which of the following statements is true?

GATE EE 2002

A dc series motor fed from rated supply voltage is overloaded and its magnetic
circuit is saturated. The torque-speed characteristic of this motor wil...

GATE EE 2001

In case of an armature controlled separately excited dc motor drive with closed loop
speed control, an inner current loop is useful because it

GATE EE 2000

The compensating winding in a dc machine

GATE EE 2000

Ratio of the rotor reactance X to the rotor resistance R for a two-phase
servomotor

GATE EE 2000

A 1.8° step, 4-phase stepper motor has a total of 40 teeth on 8 poles of stator.
The number of rotor teeth for this motor will be

GATE EE 1999

A 4-pole lap-wound DC generator has a developed power of P watts and voltage
of E volts. Two adjacent brushes of the machine are removed as they are w...

GATE EE 1996

The torque speed characteristic of a Repulsion motor resembles which of the following dc motor characteristic?

GATE EE 1996

Which type of motor is most suitable for computer printer device?

GATE EE 1996

A $$4$$ pole dynamo with wave wound armature has $$51$$ slots containing $$20$$ conductors in each slot. The induced $$emf$$ is $$357$$ volts and the ...

GATE EE 1995

A differentially compounded d.c. motor with interpoles and with brushes on the
neutral axis is to be driven as a generator in the same direction with ...

GATE EE 1993

A cumulative compounded long shunt motor is driving a load at rated torque and rated speed. If the series field is shunted by a resistance equal to t...

GATE EE 1992

Neglecting all losses, the developed torque $$(T)$$ of $$d.c.$$ separately excited motor, operating under constant terminal voltage, is related to its...

## Marks 2

GATE EE 2018

A 200 V DC series motor, when operating from rated voltage while driving a certain load,
draws 10 A current and runs at 1000 r.p.m. The total series r...

GATE EE 2017 Set 2

A 120 V DC shunt motor takes 2 A at no load. It takes 7 A on full load while running at 1200
rpm. The armature resistance is 0.8 Ω, and the shunt fiel...

GATE EE 2017 Set 2

A 220 V, 10 kW, 900 rpm separately excited DC motor has an armature resistance Ra= 0.02 Ω.
When the motor operates at rated speed and with rated termi...

GATE EE 2017 Set 1

A 220 V DC series motor runs drawing a current of 30 A from the supply. Armature and field
circuit resistances are 0.4 Ω and 0.1 Ω respectively. The l...

GATE EE 2017 Set 1

A separately excited DC generator supplies 150 A to a 145 V DC grid. The generator is running
at 800 RPM. The armature resistance of the generator is ...

GATE EE 2016 Set 1

A DC shunt generator delivers 45 A at a terminal voltage of 220 V. The armature and the shunt
field resistance are 0.01 Ω and 44 Ω respectively. The s...

GATE EE 2015 Set 2

With an armature voltage of 100 V and rated field winding voltage, the speed of a separately excited DC motor driving a fan is 1000 rpm, and its armat...

GATE EE 2015 Set 1

A separately excited DC motor runs at 1000 rpm on no load when its armature terminals are connected to a 200 V DC source and the rated voltage is appl...

GATE EE 2015 Set 1

A DC motor has the following specifications: 10 Hp, 37.5 A, 230 V; flux/pole = 0.01 Wb, number of poles = 4, number of conductors = 666, number of par...

GATE EE 2014 Set 3

A separately excited 300 V DC shunt motor under no load runs at 900 rpm drawing an
armature current of 2 A. The armature resistance is 0.5 $$\Omega$$ ...

GATE EE 2014 Set 2

A 250 V dc shunt machine has armature circuit resistance of 0.6 $$\Omega$$ and field circuit resistance
of 125 $$\Omega$$. The machine is connected to...

GATE EE 2014 Set 1

A 15kW, 230V dc shunt motor has armature circuit resistance of 0.4 $$\Omega$$ and field circuit
resistance of 230 $$\Omega$$. At no load and rated vol...

GATE EE 2012

A 220 V, 15 kW, 1000 rpm shunt motor with armature resistance of 0.25 Ω , has a rated line
current of 68 A and a rated field current of 2.2 A. The ch...

GATE EE 2011

A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature
resistance is 1.0 $$\Omega$$ and armature current is 10 A. of the excitation...

GATE EE 2010

A separately excited DC motor runs at 1500 rpm under no-load with 200 V applied
to the armature. The field voltage is maintained at its rated value. T...

GATE EE 2010

A separately excited DC motor runs at 1500 rpm under no-load with 200 V applied
to the armature. The field voltage is maintained at its rated value. T...

GATE EE 2009

Figure shows the extended view of a $$2$$ pole $$dc$$ machine with $$10$$ armature conductors. Normal brush positions are shown by $$A$$ and $$B,$$ p...

GATE EE 2008

A $$240V$$ $$dc$$ shunt motor draws $$15A$$ while supplying the rated load at a speed of $$80$$ $$rad/s$$. The armature resistance is $$0.5$$ $$ohm$...

GATE EE 2008

A $$240V$$ $$dc$$ shunt motor draws $$15A$$ while supplying the rated load at a speed of $$80$$ $$rad/s$$. The armature resistance is $$0.5$$ $$ohm$...

GATE EE 2006

A $$220V$$ $$DC$$ machine supplies $$20$$ $$A$$ at $$200V$$ as a generator. The armature resistance is $$0.2$$ ohm. If the machine is now operated as ...

GATE EE 2005

Two magnetic poles revolve around a stationary armature carrying two coils
($$c_1-c'_1$$ , $$c_2-c'_2$$ ) as shown in Figure. Consider the instant whe...

GATE EE 2005

A 50 kW dc shunt motor is loaded to draw rated armature current at any given
speed. When driven (i) at half the rated speed by armature voltage contro...

GATE EE 2005

In relation to DC machines, match the following and choose the correct
combination.
Group-I(Performance variables)
(P) Armature emf (E)
(Q) Developed...

GATE EE 2004

The armature resistance of a permanent magnet dc motor is 0.8 $$\Omega$$. At no load, the
motor draws 1.5 A from a supply voltage of 25 V and runs at ...

GATE EE 2004

A 8 pole, DC generator has a simplex wave-wound armature containing 32 coils
of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at ...

GATE EE 2003

A dc series motor driving an electric train faces a constant power load. It is
running at rated speed and rated voltage. If the speed has to be brough...

GATE EE 2002

A 200 V, 2000 rpm, 10A, separately excited d.c. motor has an armature resistance
of 2 $$\Omega$$. Rated d.c. voltage is applied to both the armature a...

GATE EE 2001

An electric motor with 'constant output power' will have a torque speed
characteristic in the form of a

GATE EE 2000

A 240 V dc series motor takes 40A when giving its rated output at 1500 rpm. Its
resistance is 0.3 ohms. The value of resistance which must be added to...

GATE EE 2000

A permanent magnet dc commutator motor has a no load speed of 6000 rpm when connected to a 120V dc supply. The armature resistance is 2.5 ohms and oth...

GATE EE 1999

A DC shunt motor is running at 1200 rmp, when excited with 220 V DC.
Neglecting the losses and saturation, the speed of the motor when connected to a
...

GATE EE 1998

A 240 V d.c. shunt motor with an armature resistance of 0.5 $$\Omega$$ has a full load
current of 40 A. Find the ratio of the stalling torque to the f...

GATE EE 1998

Match the following
List-I (Test)
(A) No load and blocked rotor test
(B) Sumpner’s test
(C) Swinburn’s test
List-II (Machine)
(1) Transformer
(2) In...

## Marks 5

GATE EE 2002

A $$230V,$$ $$250$$ $$rpm.$$ $$100A$$ separately excited $$dc$$ motor has an armature resistance of $$0.5\,\Omega .$$ The motor is connected to $$230V...

GATE EE 2001

In a $$dc$$ motor running at $$2000$$ $$rpm,$$ the hysteresis and eddy current losses are $$500$$ $$W$$ and $$200$$ $$W$$ respectively. If the flux re...

GATE EE 2001

A $$dc$$ series motor is rated $$230V,$$ $$1000$$ $$rpm,$$ $$80$$ $$A$$ (refer to Figure). The series field resistance is $$0.11\,\Omega ,$$ and the a...

GATE EE 1999

A separately excited $$DC$$ shunt motor is driving a fan load whose torque is proportional to the square of the speed. When $$100$$ $$V$$ are applied ...

GATE EE 1998

A $$DC$$ shunt generator delivers $$60$$ $$KW$$ at $$240$$ $$V$$ and $$360$$ $$rpm.$$ The armature and field resistances are $$0.015\,\,\,\Omega $$ an...

GATE EE 1997

A $$200V$$, $$10$$ $$kW$$ lap-wound $$d.c.$$ generator has $$10$$ poles and $$500$$ conductors on it's armature. If the pole face covers $$80\% $$ o...

GATE EE 1997

A $$5$$ $$kW,$$ $$200V$$ $$d.c.$$ shunt motor has an armature resistance of $$1$$ $$ohm$$ and shunt field resistance of $$100$$ $$ohms.$$ At no-load, ...

GATE EE 1997

The field coil of a two-pole $$d.c.$$ series motor is made up of two identical sections In one case
$$(i)$$ of two sections of the field coil are conn...

GATE EE 1997

At $$50\% $$ of full load, the armature current drawn by a $$d.c.$$ shunt motor is $$40$$ A when connected to a $$200$$ $$V$$ $$d.c.$$ mains. By decre...

GATE EE 1992

A separately excited $$d.c.$$ motor has an armature resistance of $$0.5$$ $$ohm.$$ It runs off a $$250$$ $$V$$ $$d.c.$$ supply drawing an armature cur...