+ Post New Thread
Results 1 to 3 of 3
  1. #1
    Member level 4
    Points: 2,117, Level: 10
    Achievements:
    7 years registered

    Join Date
    Feb 2010
    Posts
    76
    Helped
    0 / 0
    Points
    2,117
    Level
    10

    12 to 220 modified inverter

    I have built my 12 to 220 modified inverter (1000 watt).
    I use ATMEGA8 and IRF3205 in my design.
    I am sure about 220V and 50Hz on output.
    My design almost look like this.
    Click image for larger version. 

Name:	500W-Modified-Sine-Wave-Inverter-ElectroSuite.jpg 
Views:	23 
Size:	177.2 KB 
ID:	107891
    In addition to feedback signal.
    My problem is : this inverter Destroyed my three home fans (its driver board use triacs).
    Click image for larger version. 

Name:	table_fan.jpg 
Views:	5 
Size:	59.8 KB 
ID:	107890
    Is there any way to solve this problem?

    •   AltAdvertisement

        
       

  2. #2
    Super Moderator
    Points: 52,953, Level: 56

    Join Date
    Apr 2011
    Location
    Minneapolis, Minnesota, USA
    Posts
    12,951
    Helped
    2580 / 2580
    Points
    52,953
    Level
    56

    Re: 12 to 220 modified inverter

    220 modified
    This sounds as though your inverter is modified sinewave, correct? A waveform whose appearance is halfway between square wave and sinewave?

    The problem might be a matter of how high your peak voltage goes, in order to match the RMS power of a sinewave.

    A 220V sine has a peak amplitude of 220 x √2, or 311V. Does your inverter put out a greater amplitude?



    •   AltAdvertisement

        
       

  3. #3
    Advanced Member level 5
    Points: 53,716, Level: 56
    Achievements:
    7 years registered
    Audioguru's Avatar
    Join Date
    Jan 2008
    Location
    Toronto area of Canada
    Posts
    8,749
    Helped
    2053 / 2053
    Points
    53,716
    Level
    56

    Re: 12 to 220 modified inverter

    The speed control circuit using triacs in the fan expects a smooth sinewave, not the abrupt pulses of a modified sinewave.
    The 10V transformer does not produce enough output voltage for the average voltage to be 220AC. The peak voltage of 220VAC is 311V but the 10V transformer produces a peak voltage of less than 12/10V x 220V= 264V. Then the average output voltage is only 187VAC.



--[[ ]]--