| Complete IIT AIEEE ICSE ISC PMT help forum Complete help forum for students preparing for icse iit aieee cbse pmt and other related exams.Stay updated about all 2011 exams. |
Latest topics | » Nitration of aniline - IIT JEE 2018 Advanced - solved Fri Jun 08, 2018 2:34 am by adianadiadi » Diamagnetic - Paramagnetic - Ni(CO)4, [Ni(CN)4]2- and [NiCl4Fri Apr 06, 2018 1:05 am by adianadiadi » IIT JEE chemistry solved interactive question paperSun Oct 29, 2017 12:11 pm by adianadiadi » IIT JEE 2015 SOLVED QUESTION PAPERWed Oct 19, 2016 1:44 pm by adianadiadi » IIT JEE chemistry solved questionsSat Jul 18, 2015 6:15 pm by adianadiadi » General Description of Chinese Market for Foaming Agent ADC Fri May 09, 2014 2:09 pm by happybaicaitou » How to get Lowest Cost MBBS Admission?Mon Feb 24, 2014 6:39 pm by MENTOR 2014 » girl boy vashikaran specialist agori baba ji +91-9461165Tue Jan 21, 2014 6:00 pm by krshastri » STRONG LOST LOVE SPELL +91-9461165176Tue Jan 21, 2014 6:00 pm by krshastri |
feeds | |
|
Search if you can't find it here
| |
Author | Message |
---|
Abishek Active member
| Subject: Generators Wed Feb 24, 2010 11:25 pm | |
| Do we have to study the principle, theory, description and use of d.c generators? and can someone please give me notes on comparison of ac and dc generators(for variation of current and voltage with time)? |
| | | kool Active member
| Subject: Re: Generators Fri Feb 26, 2010 6:53 pm | |
| Direct current or DC electric motors work for situations where speed needs to be controlled. DC motors have a stable and continuous current. DC motors were the first and earliest motors used. They were found, however, to not be as good at producing power over long lengths. Electric companies found using DC motors to generate electric did not work because the power was lost as the electric was transmitted. Brush DC motors use rings that conduct the current and form the magnetic drive that powers the rotor. Brushless DC motors use a switch to produce the magnetic drive that powers the rotor. Direct current motors are often found in appliances around the home. Alternating current or AC electric motors are used differently based on what type of AC motor it is. Single phase AC motors are known as general purpose motors. They work well in many different situations. These AC motors work great for systems that are hard to start because they need a lot of power up front. Three phase, also called polyphase, AC motors are usually found in industrial settings. These motors also have high starting power built transmit lower levels of overall power. AC power gets its name from the fact that it alternates in power. The amount of power given off by an AC motor is determined by the amount of power needed to operate the system maY THIS be helpful to u till sm extent!!! |
| | | Abishek Active member
| Subject: Re: Generators Fri Feb 26, 2010 7:12 pm | |
| umm...i needed the notes on comparison of ac and dc GENERATORS(for variation of current and voltage with time)....btw we don't have motors right?? |
| | | kool Active member
| Subject: Re: Generators Fri Feb 26, 2010 7:15 pm | |
| ok sorry i thought that it is motors instead of dynamo.......... |
| | | Abishek Active member
| Subject: Re: Generators Fri Feb 26, 2010 7:23 pm | |
| np ....plz put up the notes for the comparison for ac and dc generators. We don't have motors. |
| | | kool Active member
| Subject: Re: Generators Fri Feb 26, 2010 7:46 pm | |
| according to me the differences shuld be the same as that is of the ac and dc.... |
| | | SHASHANK N K Active member
| Subject: Re: Generators Fri Feb 26, 2010 11:22 pm | |
| hey dont worry on dc generator coz v dont hav it for syllabus of ISC2010 |
| | | Abishek Active member
| Subject: Re: Generators Sat Feb 27, 2010 1:57 pm | |
| i checked the syllabus and it said that we needed to knw the comparison. |
| | | WinRrule Active member
| Subject: Re: Generators Sun Feb 28, 2010 3:07 pm | |
| The essential difference between an AC and a DC generator is the nature of the connection between the rotor coils and the external circuit.
In an AC generator, the brushes run on slip rings which maintain a constant connection between the rotating coil and the external circuit. This means that as the induced emf changes polarity with every half-turn of the coil, the voltage in the external circuit varies like a sine wave and the current alternates direction.
In a DC generator, the brushes run on a split-ring commutator which reverses the connection between the coil and the external circuit for every half-turn of the coil. This means that as the induced emf changes polarity with every half-turn of the coil, the voltage in the external circuit fluctuates between zero and a maximum while the current flows in one constant direction. |
| | | Sponsored content
| Subject: Re: Generators | |
|
|
| | | |
Page 1 of 1 | |
| Permissions in this forum: | You cannot reply to topics in this forum
| |
| |
| |
|