I-Flicker ye-LED ingalungiswa kanjani?

Ngenxa yokuthi sidinga ukwazi ukuthi yiziphi izingxenye zesistimu yokukhanyisa ezidinga ukuthuthukiswa noma ukushintshwa, sigcizelele ukuthi kubaluleke kangakanani ukuhlonza umthombo wokucwayiza (ingabe amandla e-AC noma i-PWM?).

Uma iI-LED STRIPiyimbangela yokucwayiza, uzodinga ukuyishintshanisa ukuze uthole entsha eyenzelwe ukushelela amandla e-AC futhi iguqule ibe yi-DC yamanje ezinzile ngempela, ebese isetshenziselwe ukushayela ama-LED. Funa i "flicker mahhala” izitifiketi nezilinganiso ezicwayizayo lapho ukhetha umugqa we-LED ikakhulukazi:

Umehluko olinganiselayo phakathi kwamazinga okukhanya aphezulu kanye nobuncane (amplitude) ngaphakathi komjikelezo ocwayizayo uvezwa njengephesenti lamaphuzu abizwa ngokuthi “iphesenti elikhanyayo.” Ngokuvamile, isibani se-incandescent siyacwayiza phakathi kuka-10% no-20%. (ngoba umcu wayo ugcina okunye ukushisa kwawo phakathi “nezigodi” kusignali ye-AC).

I-Flicker Index iyimethrikhi elinganisa inani nobude besikhathi i-LED ekhiqiza ukukhanya okwengeziwe kunokujwayelekile phakathi nomjikelezo wokucwayiza. Inkomba yokucwayiza yebulb ye-incandescent ngu-0.04.

Izinga lapho umjikelezo ocwayizayo uziphinda ngomzuzwana waziwa ngokuthi i-flicker frequency futhi ivezwa nge-hertz (Hz). Ngenxa yokuvama kwesignali ye-AC engenayo, izibani eziningi ze-LED zizosebenza ku-100-120 Hz. Amaleveli ezinkomba ezifanayo zokucwayiza nezokucwayiza azoba nomthelela omncane kuma-bulb anamaza aphezulu ngenxa yezikhathi zawo zokushintsha ngokushesha.

Ku-100–120 Hz, amalambu amaningi e-LED ayacwayiza. I-IEEE 1789 incoma ukucwayiza okuphephile okungu-8% (“ingozi ephansi”) ngale mvamisa, kanye no-3% ukuze kuqedwe ngokuphelele imiphumela yokucwayiza.

Uzodinga futhi ukufaka esikhundleni seyunithi ye-PWM dimmer uma i-PWM dimmer noma isilawuli kuyimbangela yokucwayiza. Izindaba ezinhle ukuthi njengoba imichilo ye-LED noma ezinye izingxenye kungenakwenzeka ukuthi zibe umthombo wokucwayiza, i-PWM dimmer kuphela noma isilawuli esizodinga ukushintshwa.

Uma ufuna isisombululo se-PWM esingacwayizi, qiniseka ukuthi kukhona isilinganiso sefrikhwensi esisobala ngoba iyona kuphela i-metric ye-PWM ecwayizayo ewusizo (ngoba imvamisa iyisiginali ene-100% flicker). Siphakamisa imvamisa ye-PWM engu-25 kHz (25,000 Hz) noma ngaphezulu ngesixazululo se-PWM esingacwayizi ngempela.

Eqinisweni, amazinga afana ne-IEEE 1789 abonisa ukuthi imithombo yokukhanya ye-PWM enefrikhwensi engu-3000 Hz iyifrikhwensi ephezulu ngokwanele yokunciphisa ngokugcwele imithelela yokucwayiza. Kodwa-ke, inzuzo eyodwa yokukhuphula imvamisa ibe ngaphezu kuka-20 kHz ukuthi iqeda amandla wamadivayisi wokuphakela amandla ukuze adale umsindo obhazazayo noma okhalayo. Isizathu salokhu ukuthi imvamisa ephezulu ezwakalayo kubantu abaningi ingama-20,000 Hz, ngakho-ke ngokucacisa okuthile ku-25,000 Hz, ngokwesibonelo, ungagwema ukuthi kube khona imisindo ecasulayo noma ekhalayo, engaba yinkinga uma uzwela kakhulu noma uma uhlelo lwakho lokusebenza luzwela kakhulu.