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kachew
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Posts posted by kachew
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hi guyz,
just wants to ask u guyz how to increase the voltage if i'm using mosfet and center tap tranformer to make the modified sine wave inverter? cos currently i notice that my transformer needed is too bulky....i need to make the inverter portable...thanks for u guyz help.... ;) ;) ;) -
oh...that's great....thanks mp
kachew -
hi all,
do anyone hav the manual for the eagle....??? i want to learn how to use it...thanks[table][/table] -
hi audioguru,
may i know the transition of the pulse where both mosfet are turned off? you only shows the transition where 1st and second mosfet are turned on....and i would also like to ask why we want to use the drain source of the mosfet to ground the center tap transformer?
thanks for your reply :D :D -
sorry to introduce myself, actually i am using kachew's account , i am sonny....
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hi audioguru,
i think i know what is kachew tryin to deliver.... ;D the concept can be found in any power electronics book ;D ;D and i also attach a circuit i think is similar to your concept using the cd 4001....and audioguru can u try to explain your circuit using the cd 4001 and mosfet as a switch? the center tap transformer is similar to 2 transformer circuit as i attach? thanks for your information and reply ;D ;D -
hi audioguru,
then what u means is the mosfet will only produce only 2V from each mosfet to the transformer so the is unactive in this circuit? then the previous kachew inverter is theoritical working (exclude latest modification) and the mosfet is acts as a switch?? and for 200w output the transformer have to be 12V and 1Amps??
thanks for your reply. ;) -
hi audioguru,
i think there is some problem due to the circuit....i think the CD4047 and CD4001 can be act as the control circuit for the swithing circuit which must consist of four mosfet in order to get the modified sine wave?? in the 1st cycle the signal from the control circuit will go trough the 1st then to the 1st winding of the transformer and back to 4th mosfet to get the +12V at the transformer and get the positive pulse at the output of the transfomer. in the 2nd cycle, the signal from the control signal again pass through the 2nd and 3rd mosfet again to get the negative pulse at the output of the transformer....
pls comment and thanks for your reply
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dear MP,
then what you means is when we want to use relay for 12V circuit with power rating of 200W, the we should choose relay rating of 12V and 20A? because 200/12V??
thanks for your reply -
dear audioguru,
thanks again for the help and giving so much information to me.. ;D ;D -
dear audioguru,
so the rest of the part is ok already? for the ouput in order to get lesser like 200W i shall reduce the mosfet or change the transformer value??? -
this the circuit ...thanks for your every help audioguru ....really appreciate it
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this the circuit ...thanks for your every help audioguru ....really appreciate it
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dear audioguru,
if i wanted to make and modified sinewave inverter with a single mosfet as you recommended which power mosfet can u recommen me? cos i weak in looking the datasheet...so audioguru can u teach me how to calculate the loss in the mosfet so i would know the power rating used for this modified sinewave ....thanks again... -
dear audioguru,
as u can see in the sasi inverter circuit it also uses CD 4047 but there sasi uses 4.7k not 47ohms
and may i know what is the use of the capacitor and resistor near the transformer ?? thanks
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dear audioguru,
1.can i still use the transformer u recommended earlier ???(8.5-0-8.5)
2. so for my circuit do i need to add the LM358 or straight use the CD4047??
3. in font of the power mosfet i still need to put 1k resistor? if i use low on resistance??? -
dear audiouru,
may i know wat is the power rating for the transfomer???is it usin the equation p=vi? is so in order to get 150w at output 220v then we need 0.68A and at the input then we must have at least 12.5v?Sketch the circuit of a modified sine-wave inverter and I will check it for you. Don't forget the transformer must have an output voltage about 1.414 times higher than the transformer in a square-wave inverter, to create the peak voltage of the sine-wave. Therefore instead of a 230V to 24V center-tapped (12V-0-12V) transformer you need a 230V to 17V center-tapped (8.5V-0-8.5V) transformer
tought u said this to me before??? why call me to use the LM358 again??? or do you have any other suggestion???how about i add LM358 amplifier to increase the output current from the CD4047 in order to increase the efficiency?
At only 50Hz or 60Hz, I don't think the switching speed makes any difference. If it was 50kHz or 500kHz then a lot of current is needed to charge and discharge the high gate capacitance of the Mosfets for them to switch quickly so they don't get hot. An LM358 is about the slowest opamp that is made, even slower than an old 741 opamp. It would be lousy for driving Mosfets.
Au arent the resistor used for the current equalising and as pull down resistor?? how about compare it with sasi inverter using the mosfet??The 100k resistors in series with the capacitors at the transformer have way too high a value to do anything.
thanks again...
for the mosfet...the low turn on voltage means that the resistance inside the mosfet must be low enough to turn on the mosfet ??? by equation V=IR???
thanks for your reply.... ;D ;D
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dear audioguru,
is it the 396us is the operation cycle for the mosfet?? so its take to 396us to amplified the voltage in the 1st mosfet in the positive cycle and the same time to amplified the negative cycle in the 2nd mosfet...so is it u mean that the resistor in the gate mosfet the larger the better to provide sufficient time to have to cool down time for the 1st mosfet? or the smaller value for the resistor for fast switching?? -
dear audioguru.,
thanks for checkin the circuit for me... ;D ;D and so sorry for the unclear circuit coz i draw and use digicam to take the circuit i drawn...audioguru do u hav any recommendation for the software to draw the circuit...coz i dont have any software for that...and for the comparator part shall i change to the opamp?? which opamp is more suit for the inverter? for the power mosfet i will try to find a suitable 1 and redesign the circuit as u guide me...thanks -
this is in the rar file ;)
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sorry the circuit posted seems unclear so i repost again... ;) ;)
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hi audioguru,
This is the circuit that i draw myself ;D ;D can u pls help me with the modification or check the circuit for me?? thanks...oh ya...1 more thing...how to make it to have continous power of 150W ??? ??? thanks again
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dear nthrower,
wow...how u did it? using the pwm? how much the efficiency? can u upload the schematic of your design..thanks -
dear audioguru,
oh....thanks ya lots ;D ;D oh ya...do you use any messenger such as yahoo messenger? or msn messenger?? i would like to add you in my list thanks again
Inverter Circuit 12V DC to 230VAC Sine Wave
in Electronic Projects Design/Ideas
Posted
hi guyz,
just wants to ask u guyz how to increase the voltage if i'm using mosfet and center tap tranformer to make the modified sine wave inverter? cos currently i notice that my transformer needed is too bulky....i need to make the inverter portable...thanks for u guyz help.... ;) ;) ;)