+ Post New Thread
Page 4 of 8 FirstFirst ... 23456 ... LastLast
Results 61 to 80 of 143
  1. #61
    Advanced Member level 5
    Points: 39,725, Level: 48
    Tahmid's Avatar
    Join Date
    Jun 2008
    Location
    Cornell University, Ithaca, New York, USA (from Dhaka, Bangladesh)
    Posts
    4,734
    Helped
    1675 / 1675
    Points
    39,725
    Level
    48
    Blog Entries
    19

    i need 12V DC to 220V AC inverter circuit

    i know the tl494 is running at very high frequencies,

    can i use ka3525 ONLY TO SWITCH THE H-BRIDGE MOSFETS @60HZ IN Order to gain this frequency.

    so to refresh i am using both ics TL494 AS THE MAIN IC TO GENERATE PWM

    AND KA3525 JUST TO DRIVE THE H-BRIDGE
    Yes. TL494 to drive the Push-Pull. KA3525 to drive the H-Bridge.
    Another way to look at it is,

    THE CIRCUIT IS RUNNING AT HIGH FREQUENCIES..... USING TL494

    HOW DO I GET 50HZ,

    hope u undertand where i am going wrong
    Using TL494 the circuit is running at high frequencies.
    Using KA3525 to generate 50 Hz, you drive the bridge at 50Hz and so the bridge outputs an AC voltage with 50Hz frequency.
    You also need to use a hi/lo side MOSFET driver for the H-bridge like IR2110/L6385. There are many others.


    2 members found this post helpful.

  2. #62
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    YES TAHMID i have finally got my understanding correct, thank you very much,

    just wondering if u could know, the inverter i have opened up has 2 tl494 ics inside it, am wondering how caould this combination possible generate 50hz ?

    AND

    a different inverter has only 1 pwm ic, is it possible to go from high frequency such as 100khz to 50hz by just using a 2nd order lc filter ?

    cos this inverter has a massive inductor inside it, am thinking its either using cut high frequencies, or to simply clean the end resulted signal, which do u think ?

    thanks once again


    1 members found this post helpful.

  3. #63
    Advanced Member level 5
    Points: 39,725, Level: 48
    Tahmid's Avatar
    Join Date
    Jun 2008
    Location
    Cornell University, Ithaca, New York, USA (from Dhaka, Bangladesh)
    Posts
    4,734
    Helped
    1675 / 1675
    Points
    39,725
    Level
    48
    Blog Entries
    19

    i need 12V DC to 220V AC inverter circuit

    Hi,
    Sorry for the late reply.
    I've also seen inverters using 2 TL494's. Although it's beyond its suggested parameter, they have been working at 50hz.
    I don't think just using a 2nd order lc filter, it's possible. I think that pwm ic is a microcontroller, most common I've seen is a dsPIC.
    Hope it helped.
    Tahmid.


    1 members found this post helpful.

  4. #64
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    The Inverters that use 2 TL494S i tried to reverse engineer, but still wouldnt work, the 2nd tl494 works by using both outputs collector and emitter to control the h -bridge, respectively,

    on my uf4oo4 diodes am geting an output of 650v ish volts is this correct ?, i have ordered ka3525, just waiting for it to arrive,

    1 question i need to ask is, if a inverter is rated at 150w, how is this power determined ? i mean where do u look at the datasheet

    mosfets used 05n03L *2

    will i still need to use lc filter ? and am thinking of makin it in a sine wave, any long winded ideas ?

    many thanks tahmid

    Added after 43 minutes:

    Ave seen ur circuitry using ka3525, can i used this direct to generate 50hz for h bridge drive, the IR2101 TEST CIRCUIT, umm is it at 83hz ?
    or any specific may be use to me ?

    to tahmid


    1 members found this post helpful.

  5. #65
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    hi

    I am having difficutly understandin the ka3525 IC, i need to wire it up to give 50hz to control a h-bridge,

    help anyone !



  6. #66
    Advanced Member level 2
    Points: 9,661, Level: 23
    hameeds01's Avatar
    Join Date
    Aug 2005
    Location
    Islamabad Pakistan
    Posts
    599
    Helped
    76 / 76
    Points
    9,661
    Level
    23

    Re: i need 12V DC to 220V AC inverter circuit




  7. #67
    Advanced Member level 5
    Points: 34,458, Level: 45
    Audioguru's Avatar
    Join Date
    Jan 2008
    Location
    Toronto area of Canada
    Posts
    4,052
    Helped
    829 / 829
    Points
    34,458
    Level
    45

    i need 12V DC to 220V AC inverter circuit

    Hameeds,
    The "500W" inverter you posted from Electronics-Lab has many errors. Its output might be only 100W, it has no protection diodes and its R and C in the CD4047 oscillator have completely wrong values.

    It stupidly uses two LM324 quad opamps instead of a single LM358 dual opamp.

    Its output is a simple square-wave with its voltage unregulated and many electronic products do not work from a square-wave.



  8. #68
    Advanced Member level 2
    Points: 6,295, Level: 18

    Join Date
    May 2006
    Location
    India
    Posts
    643
    Helped
    114 / 114
    Points
    6,295
    Level
    18

    Re: i need 12V DC to 220V AC inverter circuit

    check this this is from old elektor



  9. #69
    Full Member level 1
    Points: 2,988, Level: 12
    Fidelis Anyanti's Avatar
    Join Date
    Jun 2006
    Location
    Nigeria
    Posts
    108
    Helped
    17 / 17
    Points
    2,988
    Level
    12

    Re: i need 12V DC to 220V AC inverter circuit

    To build an H-Bridged Inverter, you can use the TL494 or K3525 in a chopper circuit to get something in the neighborhood of of 350V @ high frequency. You rectify its output to get clean DC, this will be your DC bus.

    Next, you will have another TL494 or K3525 circuit. This time, your frequency of oscillation will be 50Hz driving H-Bridge output of either mosfet or igbt powered by your DC bus, and your AC load is connected to the H-Bridge output directly.. with some filters .



    •   Alt26th January 2010, 15:29

      advertising

        
       

  10. #70
    Advanced Member level 2
    Points: 6,295, Level: 18

    Join Date
    May 2006
    Location
    India
    Posts
    643
    Helped
    114 / 114
    Points
    6,295
    Level
    18

    i need 12V DC to 220V AC inverter circuit

    Is any simple method to drive Full bridge without using mosfet driver IC's like Ir2110 , i have one ups using full bridge with 4 CET CEP83A3 ( I ball make ) but not using any drives or opto-coupler for driving



  11. #71
    Full Member level 1
    Points: 2,988, Level: 12
    Fidelis Anyanti's Avatar
    Join Date
    Jun 2006
    Location
    Nigeria
    Posts
    108
    Helped
    17 / 17
    Points
    2,988
    Level
    12

    Re: i need 12V DC to 220V AC inverter circuit

    There is one very simple way which i have used. I made a small driver transformer with four drive windings, two windings in the same phase to drive two adjacent outputs in an H-Bridge, and the other two which are in anti-phase to drive the other two adjacent outputs.



  12. #72
    Advanced Member level 2
    Points: 6,295, Level: 18

    Join Date
    May 2006
    Location
    India
    Posts
    643
    Helped
    114 / 114
    Points
    6,295
    Level
    18

    i need 12V DC to 220V AC inverter circuit

    thanks
    there is no gate driver transformers in the circuit (PCB)



  13. #73
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    Hi guys i need some help.

    I am using 2* IR2101 TO drive each side of the mosfets, i am putting pwm from sg3525 @50hz into both IR2101 ICs i have tested both high side and low side, (diagram from datasheet) working...and with 6us deadtime. now how do i link which source to which drain, i,ie high to low or high to high if u know what i mean

    thanks guys



  14. #74
    Full Member level 1
    Points: 2,988, Level: 12
    Fidelis Anyanti's Avatar
    Join Date
    Jun 2006
    Location
    Nigeria
    Posts
    108
    Helped
    17 / 17
    Points
    2,988
    Level
    12

    Re: i need 12V DC to 220V AC inverter circuit

    Ok, let us slow things down a little for easy understanding.
    Check this out, hope it helps.

    Enjoy.



  15. #75
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    THANK YOU VERY MUCH.......


    NOW i have another question.......... how do i convert a square wave to sine wave

    to pulse the h- bridge



  16. #76
    Advanced Member level 5
    Points: 34,458, Level: 45
    Audioguru's Avatar
    Join Date
    Jan 2008
    Location
    Toronto area of Canada
    Posts
    4,052
    Helped
    829 / 829
    Points
    34,458
    Level
    45

    Re: i need 12V DC to 220V AC inverter circuit

    Quote Originally Posted by KRYCHEK
    how do i convert a square wave to sine wave to pulse the h- bridge?
    The 12V from the battery is converted to 345VDC with a power converter circuit.
    The H-bridge operates from the 345VDC. The H-bridge is pulsed with PWM at about 25kHz. The PWM is modulated with a 50Hz sine-wave. The output of the H-bridge is filtered with an LC lowpass filter into a 50Hz 220VAC sine-wave. Since the carrier frequency is 25kHz then the filter's inductor and capacitor are small.

    If you tried to filter a 50Hz square-wave into a sine-wave then the resistance of the huge expensive inductor will be so high that most the inverter's power will be wasted in it. Then the output power will be very low.



  17. #77
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    HI Audio guru

    Currently i have designed a modified sinewave inverter

    The H-Bridge is powered using 350V, and pulsed using 50Hz, using sg3525

    Can you please explain to me, how can i generate 25kHz.....

    Then if i pass this frequency through an LC filter, how will i get sine 50hz

    Please correct me if I am wrong

    Thnak you very much

    Added after 1 hours 31 minutes:

    i also need to know, how do i test my inverter,

    I mean i need to test it using different load and draw up a graph

    150w

    230V

    how many ohms do i start off and what value do i finish at

    THANKS GUYS



  18. #78
    Advanced Member level 5
    Points: 34,458, Level: 45
    Audioguru's Avatar
    Join Date
    Jan 2008
    Location
    Toronto area of Canada
    Posts
    4,052
    Helped
    829 / 829
    Points
    34,458
    Level
    45

    Re: i need 12V DC to 220V AC inverter circuit

    Quote Originally Posted by KRYCHEK
    HI Audio guru

    Currently i have designed a modified sinewave inverter

    The H-Bridge is powered using 350V, and pulsed using 50Hz, using sg3525

    Can you please explain to me, how can i generate 25kHz.....

    Then if i pass this frequency through an LC filter, how will i get sine 50hz
    A modified sine-wave inverter has a square-wave output with only two steps. Since its frequency is only 50Hz then its stepup transformer is huge and expensive and it is impossible to LC filter into a sine-wave without reducing its power output to almost nothing since the huge and expensive inductor would have a high resistance and will get hot.

    Inexpensive sine-wave inverters use PWM at about 25kHz and the PWM is modulated with a 50hz sine-wave. Then the LC filter is small and inexpensive. the DC to DC converter can also use the 25kHz frequency and its transformer will be small and inexpensive with a ferrite core.
    Any simple oscillator can generate 25kHz. The minimum oscillator frequency for an SG3525 is 100kHz so use 120kHz. The oscillator in a TL494 PWM controller IC (it is used in many sine-wave inverters) is from 1kHz to 300kHz.

    how do i test my inverter?
    I mean i need to test it using different load and draw up a graph

    150W, 230V

    how many ohms do i start off and what value do i finish at
    An inverter should be tested with an adjustable load resistance. Use the wire from an electric toaster or a heater. Light bulbs draw 10 times their rated power when cold so are a poor load for an inverter. Use Ohm's Law to calculate the resistance.

    Different loads and different battery voltages will affect the output voltage of your inverter. You will want to add negative feedback for voltage regulation.



  19. #79
    Member level 1
    Points: 1,047, Level: 7

    Join Date
    Jan 2010
    Location
    HUDDERSFIELD UK
    Posts
    38
    Helped
    5 / 5
    Points
    1,047
    Level
    7

    Re: i need 12V DC to 220V AC inverter circuit

    Hi Guru

    I am using tl494 for high frequency to convert to 350V dc BUS

    and sg3525 for 50Hz

    SO if i step up my frequency for sg3525 to about 120Khz....feed it into H-Bridge.... and then use a filter.... should i then get a sine wave i mean does this seem reasonable,

    the pulses from the sg3525 are about 5 v i think which feed into ir2101......

    thanks



  20. #80
    Advanced Member level 5
    Points: 34,458, Level: 45
    Audioguru's Avatar
    Join Date
    Jan 2008
    Location
    Toronto area of Canada
    Posts
    4,052
    Helped
    829 / 829
    Points
    34,458
    Level
    45

    i need 12V DC to 220V AC inverter circuit

    You need to use a 50Hz sine-wave to modulate the SG3525. The LC filter at the output removes most of the 120kHz switching frequency.


    1 members found this post helpful.

+ Post New Thread
Please login
Page 4 of 8 FirstFirst ... 23456 ... LastLast

LinkBacks (?)

  1. 12th December 2011, 16:59
  2. 5th December 2011, 07:35
  3. 9th September 2011, 04:57