Iyini i-Total Harmonic Distortion(THD)?
I-Total Harmonic Distortion (THD) iwubudlelwane befrikhwensi yokusebenza esiza ukulinganisa izinga uhlelo olukhipha ngalo okokufaka kwekhophi. . Kuyisilinganiso sokuhlanekezela kwe-harmonic okukhona kusignali futhi kuchazwa njengenani lesamba samandla azo zonke izingxenye ze-harmonic kumandla wemvamisa eyisisekelo. Lokhu kuzophathelene nezinto ezinikezwa amandla kuphela futhi yiyona kuphela ingxenye ekhiqiza noma yiluphi uhlobo lokuvama. Ukuncipha kwevelu ye-THD, umsindo omncane noma ukuhlanekezela ekuphumeni kwesistimu.
Kumvamisa ngayinye yokuhlola, inani le-THD liphakathi kuka-0 no-1:
ZERO - Inani eliseduze noziro lisho ukuthi okukhiphayo kunokuhlanekezela okuphansi kwe-harmonic. Igagasi le-sine eliphumayo linengxenye yokuvama efana nokokufaka.
OKUNYE - Inani elisondele ku-1 lisho ukuthi kunokuhlanekezela okuningi kwe-harmonic kusiginali. Cishe konke okuqukethwe kwefrikhwensi kusiginali kuhlukile kubuningi besiginali yokufaka.
I-THD nayo ingavezwa njengephesenti, isuka ku-0 iye ku-100%, lapho i-100% ihambisana no-1.
Ezinhlelweni eziningi, i-THD ephansi iyadingeka. I-THD ephansi isho ukuthi okukhiphayo kwesistimu kuyafana nokokufaka kwesistimu okunokuhlanekezela okuncane.
Kungani ibaluleke kangaka?
Okokuqala, njengencazelo, ama-harmonics ama-voltage noma imisinga imvamisa yawo ingukuphindaphinda kwefrikhwensi eyisisekelo, futhi i-Australia ingu-50 Hz: 100, 150, 200 Hz, njll. I-Total Harmonic Distortion (THD) iyisamba sazo zonke izingxenye ze-harmonic imvamisa eyisisekelo ekhona ezintweni ezingaqondile zikagesi neze-elekthronikhi.
Izishayeli ze-LED ziyimithombo yamandla kagesi ezikhanyisini ze-LED eziqukethe amadivaysi e-inductive (izingxenye zokusabela kanye ne-capacitive). Amadivayisi angewona omugqa ngenxa yokuthi ashintsha i-waveform yamanje ethathwe kusignali kagesi enikeziwe futhi abonakale ene-sinusoidal encane.
Iningi labashayeli be-LED lihlanganisa nebhuloho le-diode lokulungisa isignali yokufaka ye-AC ukuze isebenzise imojuli ye-DC LED. Ukusebenza kokushintsha kwala mabhuloho e-diode kukhiqiza amandla angaqhubeki agcina ehlanekezela igagasi le-sine.
Ngakho-ke, lapho umshayeli we-LED exhunywe ohlelweni lwamandla amakhulu, ukhiqiza ama-harmonic currents ahlanekezela i-voltage yokuhlinzeka. Futhi izibani eziningi (ezinabashayeli be-LED abangewona umugqa) kumjikelezo, ukuphazamiseka okukhulu ohlelweni lokusabalalisa amandla, okwenza lungasebenzi kahle, kuthinte ukusebenza kwamanye amadivaysi nokushisa i-wiring.
Kungakho imininingwane kagesi yemishini yokukhanyisa ekufakweni okusha ngokuvamile idinga ukuthi iTHD ephezulu yesibani ibe ngaphansi kuka-15%.