1 Answer

Answer :

Cycloconverter is a device which convert fixed AC input frequency to variable output frequency or variable input frequency to fixed output frequency.

There are two types of cycloconverter

1.  Step down cycloconverter

2. Step Up cycloconverter

In Step Up cycloconverter forced commutation is required.

In step down cycloconverter forced commutation is not required

There are two types of single phase cycloconverter

1. Midpoint type

2. Bridge type

Midpoint type single phase cycloconverter consist of centre tap transformer And four thyristors.

Bridge type single phase cycloconverter consists of eight thyristors. Four thyristors are for positive converter and four thyristors are for negative converter.

Related questions

Description : three phase to single phase cycloconverter

Last Answer : three phase to single phase cycloconverter

Description : what is cycloconverter ?

Last Answer : Cycloconverter is a device which convert fixed AC input frequency to variable output frequency or variable input frequency to fixed output frequency.

Description : What is meant by negative converter group in a cycloconverter?

Last Answer : The part of the cycloconverter circuit that permits the flow of current during negative half cycle of output current is called negative converter group.

Description : What is meant by positive converter group in a cycloconverter?

Last Answer : The part of the cycloconverter circuit that permits the flow of current during positive half cycle of output current is called positive converter group.

Description : A cycloconverter is a   (a) frequency change r(fc) from higher to lower frequency with one-stage conversion   (b) fe from higher to lower frequency with two-stage conversion   (c) fc from lower to higher frequency with one-stage conversion   (d) Either (a) or (c)

Last Answer : A cycloconverter is a   (a) frequency change r(fc) from higher to lower frequency with one-stage conversion   (b) fe from higher to lower frequency with two-stage conversion   (c) fc from lower to higher frequency with one-stage conversion   (d) Either (a) or (c)

Description : Explain cycloconverter and its types.

Last Answer : Cycloconverter: Cycloconverter is an AC to AC converter which converts input AC into variable AC. It changes frequency. Basically, there are two types of cycloconverter one is step up ... Disadvantages of cycloconverter: So many thyristors are required in cycloconverter.

Description : Draw and explain the circuit diagram for measurement of single phase power using dynamometer type wattmeter. 

Last Answer : Circuit diagram for measurement of single phase power using dynamometer type wattmeter: Explanation: It consists of two stationary coils, called current coils and one moving coil, called voltage or ... i.e. power. The meter can be calibrated directly to indicate the power in watts. 

Description : Explain MCB and ELCB with connection diagram supplying single phase load. 

Last Answer : OR OR Explanation: * MCB provides short circuit protection. * MCB provides overload protection * ELCB provides earth fault protection. * MCB is in series with ... occurs, the ELCB cuts off the power within the time of 0.1 sec. automatically to protect the personnel. 

Description : Why is a capacitor used in a single phase motor and not in three phase motor ?

Last Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.

Description : working principle of single phase motor

Last Answer : The Stator of single phase induction motor houses two windings  1. Main (Running) winding 2. Auxiliary (Starting ) winding Rotor of single phase induction motor is ... with starting winding or a capacitor may be permanently connected in series with Auxiliary (Starting ) winding.

Description : (a) Define permeability. (b) Define MMF. (c) Define form factor of an alternating quantity. (d) Define frequency and time period of an alternating quality. (e) Define transformation ratio of transformer. ... and state the meaning of each term used. (g) Give two applications of single phase motors. 

Last Answer : Permeability : It is the ability of a magnetic/Non magnetic material to allow setting up of flux in it.  MMF : The magneto motive force (MMF) is the force required to setup flux in a magnetic / ... applications of single phase motors : Water pumps, ceiling fan, lathe machine

Description : Explain the working of a single phase capacitor start induction motor. 

Last Answer : Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc

Last Answer : Advantages of three phase transformer over bank of single phase transformers:  For identical magnitudes of power transformation, i) Saving in copper conductor. ii) Saving in electromagnetic core material. ... material such as insulating oil. v) Saving in overall cost. vi) Higher efficiency.

Description : Draw neat labeled diagram of single phase AC locomotive showing its various equipments of power circuit and give function of each equipment used in power circuit.

Last Answer : Functions of equipment: 1) circuit breaker: disconnects the locomotive equipment from the supply in the event of fault in the equipment / loco. 2) On load tap changer, used to control the ... 6) Traction motor: operates as per the required operating characteristics to take on the traction load.

Description : State the classification of single phase induction motors.

Last Answer : Types of single phase induction motors: 1. Split phase induction motor. 2. Capacitor start inductor motor. 3. Capacitor start capacitor run induction motor. 4. Permanent split capacitor motor. 5. Shaded pole induction motor. 

Description : In a single-phase induction motor, the operating direction is determined by the ________ A) Rotor B) Stator C) Starting circuit D) None of these

Last Answer : In a single-phase induction motor, the operating direction is determined by the Starting circuit

Description : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Last Answer : What is the slip (as a percentage) when a 6 pole single phase induction motor operating on 220 V and 60 Hz is rotating at speed of 1140 rpm? A) 60% B) 5% C) 10% D) None of these

Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Last Answer : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Description : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is (A) 216 V (B) 226 V (C) 234 V (D) 236 V

Last Answer : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is 226 V

Description : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is (A) 28.2 mm (B) 26.4 mm (C) 24.4 mm (D) 22.0 mm

Last Answer : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is 22.0 mm

Description : In the capacitor-start, capacitor-run single-phase induction motor (A) two capacitors are connected across the main winding (B) when the centrifugal switch opens, the permanent capacitor is left ... left in the main winding circuit (D) two capacitors are connected across the auxiliary winding.

Last Answer : In the capacitor-start, capacitor-run single-phase induction motor when the centrifugal switch opens, the permanent capacitor is left in the auxiliary winding circuit

Description : The primary turns of a 444 V/222 V, 50 Hz single-phase transformer with a core cross-sectional area of 100 cm2, and a maximum flux density of 1.0 T is (A) 100 (B) 200 (C) 222 (D) 400

Last Answer : The primary turns of a 444 V/222 V, 50 Hz single-phase transformer with a core cross-sectional area of 100 cm2, and a maximum flux density of 1.0 T is 200

Description : The meter constant of a single-phase 230 V induction watt hour meter is 400 revolutions per kWh. The speed of the meter disc for a current of 10 A of 0.9 pf lagging will be

Last Answer : The meter constant of a single-phase 230 V induction watt hour meter is 400 revolutions per kWh. The speed of the meter disc for a current of 10 A of 0.9 pf lagging will be 13.80 rpm

Description : The current coil of a single-phase energy meter is wound on (a) One limb of the laminated core (b) Both the limbs of the laminated core with same number of turns (c) Both the limbs of the laminated core with different number of turns (d) The centre of the limb on the laminated core

Last Answer : The current coil of a single-phase energy meter is wound on Both the limbs of the laminated core with same number of turns

Description : One single-phase energy meter operating on 230 V and 5 A for 5 hours makes 1940 revolutions. Meter constant is 400 rev/kWh. The power factor of the load is

Last Answer : One single-phase energy meter operating on 230 V and 5 A for 5 hours makes 1940 revolutions. Meter constant is 400 rev/kWh. The power factor of the load is 0.8

Description : A single-phase ac voltage source has 200 V rms and a system connected consumes an active power of 300 W. What is the reactive power consumed by the system if 2.5 A rms current is drawn ?  (a) 100 VAR (b) 200 VAR (c) 300 VAR (d) 400 VAR

Last Answer : A single-phase ac voltage source has 200 V rms and a system connected consumes an active power of 300 W. What is the reactive power consumed by the system if 2.5 A rms current is drawn ? 400 VAR

Description : If the conductive loop on the rotor of a simple two -pole, single-phase generator rotates at the rate of 400 rps. The frequency of the induced output voltage will be: A. 40 Hz B. 100 Hz C. 400 Hz D. indeterminable

Last Answer : If the conductive loop on the rotor of a simple two -pole, single-phase generator rotates at the rate of 400 rps. The frequency of the induced output voltage will be: 400 Hz

Description : Comparing the total copper cross sections in terms of current-carrying capacity for a single-phase and a three-phase 120 V system with effective load resistance of 15Ω, will yield: A. single-phase 32 A; three-phase 16 ... C. single-phase 8 A; three-phase 4 A D. single-phase 16 A; three-phase 0 A

Last Answer : Comparing the total copper cross sections in terms of current-carrying capacity for a single-phase and a three-phase 120 V system with effective load resistance of 15Ω, will yield: single-phase 16 A; three-phase 8 A 

Description : A two -winding single phase transformer has a voltage regulation of 4.5% at full - load and unity power -factor. At full -load and 0.80 lagging power-factor, the voltage regulation will be: (A) 4.5% (B) less than 4.5% (C) more than 4.5% (D) none of the above

Last Answer : A two -winding single phase transformer has a voltage regulation of 4.5% at full - load and unity power -factor. At full -load and 0.80 lagging power-factor, the voltage regulation will be: more than 4.5%

Description :  Which single phase ac motor will you select for record players and tape recorders?  a) Hysteresis motor b) Shaded pole motor c) Reluctance motor d) Two value capacitor motor

Last Answer : Which single phase ac motor will you select for record players and tape recorders?  Hysteresis motor

Description : A capacitor start, capacitor run single phase induction motor is basically a : -  a) ac series motor b) dc series motor c) 2 phase induction motor d) 3 phase induction motor

Last Answer : A capacitor start, capacitor run single phase induction motor is basically a : -  2 phase induction motor 

Description : A single phase, half-wave, controlled rectifier has 400 sin (314 t) as the input voltage and R as the load. For a firing angle of 60° for the SCR, the average output voltage is   (a) 240/π (b) 400/π (c) 300/π (d) 200/π 

Last Answer : C

Description : A single phase energy meter has a constant of 1200 revolution/kWh. When a load of 200 W is connected, the disc rotates at 4.2 revolutions per min. If the load is on for 10 hours, the meter records an excess of   (a) 0.1 kWh (b) 0.2 kWh (c) 1.0 kWh (d) 2.0 kWh 

Last Answer : 2

Description : Starting torque can be obtained in the case of a single phase induction motor with identical main and auxiliary windings by connecting:  (1) A capacitor across the mains (2) A capacitor in ... with the auxiliary winding (4) Equal value capacitors in series with the main and the auxiliary windings

Last Answer : Starting torque can be obtained in the case of a single phase induction motor with identical main and auxiliary windings by connecting:  A capacitor is series with the auxiliary winding.

Description : In a capacitor start single-phase induction motor, the capacitor is connected in:  (A) series with the main winding (B) series with the auxiliary winding (C) series with both the windings (D) parallel with the auxiliary winding .

Last Answer : In a capacitor start single-phase induction motor, the capacitor is connected in: series with the auxiliary winding 

Description : A single phase transformer rated at 3000 kVA, 69 kV 4.16 kV, 60 Hz has a total internal impedance Zp of 127 ohm, referred to the primary side. Calculate the primary current if the secondary is accidentally short circuited.  (A) 43.5 A (B) 543 A (C) 9006 A (D) 721 A 

Last Answer : 543A

Description : A single phase 60 Hz generator supplies an inductive load of 4500kW at a power factor of 0.80 lagging by means of a 20 km long overhead transmission line. The line resistance and inductance are 0.0195 ohm and 0.60 mH ... voltage regulation of the line.  (A) 12.59% (B) 16.34% (C) 32.68% (D) 41.15% 

Last Answer : Answer is C

Description : if the rated voltage from the power lines is applied to the primary of a single-phase transformer which is operated on no-load, then

Last Answer : if the rated voltage from the power lines is applied to the primary of a single-phase transformer which is operated on no-load, then input voltage is sinusoidal and input current is non sinusoidal.

Last Answer : The m.m.f. produced by a single phase winding is pulsating and stationary.

Last Answer : The squirrel-cage winding of a single-phase motor is placed in the rotor.

Last Answer : The series magnet of a single phase Energy meter consists of coil of thick wire of few turns.

Description : write short notes on single phase system.

Last Answer : A "phase" in an electrical system is often referred to as the waveform (may be voltage or the current) of the power supply. The waveform in an AC system is typically ... domestic household or commercial supplies and street lighting. Industrial supplies requires three phase electrical supply .

Description : Why a single phase motor is not a self starting motor

Last Answer : The motor mechanical degree 360 degree this must covered revolving field so single phase to starting need starting winding with 90 degree to main winding