The output of the rectifier pulsating in nature, it consists of a desired DC component of voltage and unwanted ripple components. These ripple components are removed by placing filter circuit at the output of the rectifier.Types of filters: 1. capacitor filter 2. series inductor filter 3. LC filters of following two types (a)capacitance input filter (b)inductance unput...

gajanan ghawale

• Jun 27th, 2017

In order to remove DC component which are left behind the Rectifier circuit output, the circuit consist combination of resistor capacitor or Inductor is known as filter

Deepali Goyal

• Jun 10th, 2017

Filter is used to select only a particular range of frequencies. Filters are basically are of two types
1. Active Filters
2. Passive Filters

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How we can step-up or step-down the DC voltage directly?

S.Ghosh

• May 23rd, 2012

A chopper is nothing but a thyristor/SCR/transistor circuit which operates with the principle of PWM (Pulse Width Modulation). If you need to boost DC voltage with chopper, additional circuits includi...

sai charan

• May 20th, 2012

this can be done by using chopper.chopper is a dc equivalent of a.c transformer to which d.c input which is to be stepped up is applied at input terminals and output is taken from output terminals whi...

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What is the power factor?

bashir varsi

 Profile Answers by bashir varsi Questions by bashir varsi

• Jun 14th, 2009

Power factor is the ratio of active power to apperant power. for better energy efficiency it should be unity.  

jeet29

 Profile Answers by jeet29 Questions by jeet29

• Jun 8th, 2009

Power Factor means that what amount of the power the circuit is using. If the power factor is .807 that means circuit is using 80.7% of power and the remaining 19.3% is returning back to supplying source.

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What would happen if a transformer is made to operate at 60Hz instead of 50Hz ?

expertnayak

 Profile Answers by expertnayak Questions by expertnayak

• Jun 8th, 2009

In transformer eddy current lossesPe=Kv^2 it is not dependent on frequency so only hyteresis losses will get affectedPh=KfB^x

jeet29

 Profile Answers by jeet29 Questions by jeet29

• Jun 8th, 2009

If we are connecting a 50 hz transformer to a 60 hz transformer then there hystersis and eddy current both losses increases considerably (for detail check effect of frequency on transformer losses).

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The single phase induction motor starts with two phases(Using capacitor). Why can't the three phase induction motor starts with two phase?

jeet29

 Profile Answers by jeet29 Questions by jeet29

• Jun 8th, 2009

For the starting of a single phase motor we need two different fields and the resultant of both the fields works as the operating field revolving the motor in the direction of strong field (for more...

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KaranSorout  

 Profile Answers by KaranSorout Questions by KaranSorout

• Member Since Jul-2006 | Jul 13th, 2006

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The power ratio between Star to Delta is 1:3

Explanation:

 

Let?s suppose V_s be the supply voltage per phase.

So the line voltage of the supply will be ?3V_s.

Now assume any type of load; for simplicity I?m assuming it a only resistive load.

And let it be ?R? per phase.

 

For Delta connected load:

 

Calculation for per phase power; P_D= I²R

 

Where I ? load current (per phase)

And,

I = ?3V_s/R       {as line voltage of the supply is directly applied to the phase of the delta load}

So,

            P_d = (?3V_s/R )²R = 3V_s²/R  watts per phase.

For 3 phases:

            P_3D = 3P_d = 3*3V_s²/R = 9V_s²/R watts.

 

Now for Star connected load:

 

P_S = I²R = (V_s/R)²R = V_s²/R watts

For 3 phases: P_3S = 3P_S = 3 V_s²/R watts

 

Conclusion:

P_3S / P_{3D  =}  3V_s²/R / 9V_s²/R = 1/3

It may be better concluded by drowing figures. If any variations, can connect to me through karan.sorout@gmail.com  

RUP KAMAL KUTUM

• Feb 3rd, 2018

Well first you assumed voltage per phase as Vs and Line voltage as sqrt(3) x Vs: Which is for star connection. Then, you assumed the same thing for Delta Connection(where line and phase voltages are t...

Anbumozhi R

• Dec 3rd, 2017

Power is Same. Whether it is star to Delta conversion or Delta to star conversion. Power is 1:1

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