Bita kan Tsarin Halitta da Amfani da Sarrafa Na'urorin Canza Wutar Lantarki na Matsakaicin Babban Wutar Lantarki III

3.3 Tsarin Tsarin Matsayi Mai Mannewa Mai Mataki Da Yawa

An nuna yanayin ƙasa mai matakai da yawa na Neutral Point Clamped (NPC). Baya ga yanayin ƙasa mai ɗaure da diode-clamped NPC, yanayin ƙasa na NPC ya haɗa da nau'in capacitor mai tashi da nau'in clamped hybrid, da sauransu. Duk da haka, saboda girman capacitor mai girma, yanayin ƙasa na NPC har yanzu galibi suna amfani da na'urorin canzawa marasa aiki ko masu aiki don ɗaurewa. Idan aka ɗauki yanayin ƙasa mai ɗaure da diode-clamped multilevel misali, a cikin yanayin ƙasa mai ɗaure da mataki uku na rectifier, kowace ƙafar mataki ta ƙunshi transistors masu sauyawa da diodes masu ɗaurewa, waɗanda aka haɗa a layi ɗaya zuwa bas ɗin DC mai ƙarfin lantarki guda ɗaya. Littattafai sun ba da shawarar yanayin ƙasa na PET guda ɗaya tare da matakin rectifier ta amfani da da'irar diode-clamped mai matakai huɗu. Bas ɗin DC mai ƙarfin lantarki guda ɗaya yana biye da DABs masu haɗawa da shigarwa-jerin fitarwa-daidai, kamar yadda aka nuna. Ana iya faɗaɗa wannan yanayin ƙasa zuwa tsarin matakai uku, kuma ana iya canza adadin matakan ƙarfin lantarki bisa ga matakan ƙarfin lantarki masu jure wa na'ura da matakin ƙarfin lantarki mai ƙarfi. Kamar tsarin MMC, tsarin NPC kuma ana iya amfani da shi a matakin keɓewa, yana haɗa bas ɗin DC mai ƙarfin lantarki mai girma zuwa Na'urar Canzawa ta Warewa, kamar yadda aka nuna. Littattafai sun yi amfani da na'urar NPC mai manne da diode mai matakai uku a gefen babban ƙarfin lantarki na na'urar LLC resonant converter, suna tabbatar da shi akan samfurin 166kW/2kV ~ 400V. Littattafai sun yi amfani da da'irar NPC mai manne da diode mai matakai uku zuwa ga DAB mai matakai uku, wanda ya cimma cikakkiyar ƙarfin lantarki na DAB da halayen yanzu.

Lokacin da ake amfani da tsarin NPC a matsayin matakin gyarawa, ba ya buƙatar bas ɗin DC da aka ware, wanda ke rage adadin masu canza wutar lantarki na matakin keɓewa. Bugu da ƙari, a cikin tsarin matakai uku, babu wani ƙarfin lantarki mai layi biyu-mita a kan bas ɗin. Duk da haka, saboda tsarin da aka manne yana buƙatar adadi mai yawa na na'urorin mannewa, adadin na'urorin mannewa yana ƙaruwa yayin da adadin matakan ke ƙaruwa, yana sa faɗaɗa matakin ya zama da wahala da kuma rashin aiki mai yawa. Dangane da sarrafawa, kwararar da ke gudana a cikin kowane capacitor na mai canza NPC sun bambanta, wanda ke haifar da rashin daidaiton ƙarfin capacitor. Ga tsarin NPC sama da matakai uku, babu ingantaccen tsarin daidaita ƙarfin lantarki. Bugu da ƙari, lokutan aiki marasa daidaito na mannewa a ciki da wajen makamai suna haifar da dumama mara daidaito, wanda za'a iya warware shi kawai ta hanyar canza tsarin da'ira gaba ɗaya.

Matsaloli da yawa da faɗaɗa matakin ke haifarwa na nufin cewa ana iya amfani da topologies na NPC ne kawai a matakan matsakaici/babba na ƙarfin lantarki ta hanyar haɗin jerin na'urori ko amfani da na'urorin SiC masu ƙarfin lantarki. Duk da haka, a ƙananan matakan ƙarfin lantarki, idan aka kwatanta da topology na H-gada ɗaya, NPC mai matakai uku yana da rabin ƙarfin juriya da ƙarfin lantarki kawai akan kowane transistor mai sauyawa, yayin da yake fitar da ƙarin matakan ƙarfin lantarki, wanda ke haifar da ƙarancin buƙatun tace fitarwa. Yana da fa'idodi masu yawa na aikace-aikace a matsayin matakin inverter a gefen ƙarancin ƙarfin lantarki na PET. Misali, wallafe-wallafe sun yi amfani da NPC mai manne da diode mai matakai uku a matsayin matakin inverter na PET don tuƙa motar matakai uku, gudanar da tabbatar da gwaji da cimma kyakkyawan aikin tuƙi da aikin hayaniya.