PI工程師你好,現(xiàn)本人制作了一多路輸出的反激電源,是基于STACKFET拓?fù)浣Y(jié)構(gòu),芯片為TNY274G.
輸入電壓為300-600VDC
5路輸出分別為:
1 17V/6mA 25T isolated
2 17V/6mA 25T isolated
3 17V/6mA 25T isolated
4 17V/2mA 25T same GND with 5V
5 5V/70mA 8T
變壓器:
Primary: 150T 1.1mH air gap:0.45mm
E16/5 14PIN BOBBIN,ISOLATION:800V
Test voltage:2.5kV
現(xiàn)在對(duì)電源已經(jīng)作了一周的測(cè)試,但是效率始終不能夠提高,只有45%-50%本人用5V作為反饋回路,同時(shí)由于此電源應(yīng)用于solar inveter, 所以optocouple 在此項(xiàng)目中禁止用.因此采用的是偏置線圈的反饋,在此想請(qǐng)教PI的工程師,對(duì)于如此高壓輸入,小功率輸出的電源怎樣才能提高效率呢?本人期望的效率是70%,但是覺得很難,功率太小了.請(qǐng)PI的工程師多多賜教,給與建議.
請(qǐng)教PI工程師:關(guān)于基于STACKFET拓?fù)?用TNY274G制作的700mW反激電源
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@liujiehit2000
PI的工程師不在嗎?怎么沒有回復(fù)呢?自己頂一下,壇子里的電源高手給個(gè)建議,看看有沒有什么辦法解決效率問題,明天我會(huì)將原理圖以及PCB的圖放上來,請(qǐng)高手賜教!
建議你做以下實(shí)驗(yàn):
1.260vac輸入條件下,該電源的效率,
2.260vac輸入條件下,不用stack的mosfet,效率能到多少.
通常在條件2下,用274做5v輸出為主的設(shè)計(jì)或者多路輸出,效率也只能在70%左右,輸入電壓提高會(huì)使變壓器及開關(guān)管的結(jié)電容損耗增加(這個(gè)你可以看380v跟600v輸入時(shí)效率有無差別),另外附加的mosfet會(huì)有額外損耗,在輸出功率很小的情況下,一點(diǎn)點(diǎn)多的損耗都會(huì)對(duì)效率有很大影響.
最后,建議檢查一下功率計(jì)讀數(shù)是否準(zhǔn)確.
1.260vac輸入條件下,該電源的效率,
2.260vac輸入條件下,不用stack的mosfet,效率能到多少.
通常在條件2下,用274做5v輸出為主的設(shè)計(jì)或者多路輸出,效率也只能在70%左右,輸入電壓提高會(huì)使變壓器及開關(guān)管的結(jié)電容損耗增加(這個(gè)你可以看380v跟600v輸入時(shí)效率有無差別),另外附加的mosfet會(huì)有額外損耗,在輸出功率很小的情況下,一點(diǎn)點(diǎn)多的損耗都會(huì)對(duì)效率有很大影響.
最后,建議檢查一下功率計(jì)讀數(shù)是否準(zhǔn)確.
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PI engineer, I have made the same experiment without stackfet topology. Then the efficiency is the same with before result. Thereby I think maybe the issue is not the IC. Until now I make some other improvment on that, and the efficiency is about 68,55%. It is little more highter than before. Now I will attachment the schematic, and please help me improve that. I hope that efficiency can reach over 70% at 750mW output power. and input voltage is from 300-600V
output power is about 750mW. 132311190300361.pdf
output power is about 750mW. 132311190300361.pdf
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