【光伏逆變器技術指標】太陽能發電系統中光伏逆變器應該如何選擇?

1、額定輸出功率

額定輸出(chu)功(gong)(gong)(gong)(gong)率(lv)(lv)表示光(guang)伏逆(ni)變器(qi)向負載供(gong)電(dian)(dian)(dian)的(de)(de)能力。額定輸出(chu)功(gong)(gong)(gong)(gong)率(lv)(lv)高的(de)(de)光(guang)伏逆(ni)變器(qi)可以帶更多的(de)(de)用(yong)電(dian)(dian)(dian)負載。選(xuan)用(yong)光(guang)伏逆(ni)變器(qi)時應首(shou)先考(kao)慮具(ju)有足夠的(de)(de)額定功(gong)(gong)(gong)(gong)率(lv)(lv)，以滿足最大(da)負荷下設(she)備(bei)對電(dian)(dian)(dian)功(gong)(gong)(gong)(gong)率(lv)(lv)的(de)(de)要求，以及系統的(de)(de)擴容及一些臨時負載的(de)(de)接入。當用(yong)電(dian)(dian)(dian)設(she)備(bei)以純(chun)電(dian)(dian)(dian)阻(zu)性負載為生或功(gong)(gong)(gong)(gong)率(lv)(lv)因數(shu)大(da)于0.9時(shi)，一般選取(qu)光伏逆變器的額定輸出(chu)功率比用電設備總功率大10%~15%。

2、輸出電壓的調整性能

輸出(chu)電(dian)壓(ya)的(de)調(diao)整(zheng)性能表示光(guang)(guang)(guang)伏(fu)(fu)(fu)逆(ni)變(bian)器輸出(chu)電(dian)壓(ya)的(de)穩壓(ya)能力。一般光(guang)(guang)(guang)伏(fu)(fu)(fu)逆(ni)變(bian)器產品都給(gei)(gei)出(chu)了(le)當(dang)直(zhi)流輸入(ru)電(dian)壓(ya)在允許波動(dong)范(fan)圍變(bian)動(dong)時(shi)，該光(guang)(guang)(guang)伏(fu)(fu)(fu)逆(ni)變(bian)器輸出(chu)電(dian)壓(ya)的(de)波動(dong)偏(pian)差(cha)的(de)百分率，通常稱為電(dian)壓(ya)調(diao)整(zheng)率。高性能的(de)光(guang)(guang)(guang)伏(fu)(fu)(fu)逆(ni)變(bian)器應同時(shi)給(gei)(gei)出(chu)當(dang)負(fu)載由零(ling)向100%變(bian)化時，該光(guang)伏逆變(bian)器輸出電(dian)壓的偏(pian)差百分率，通(tong)常稱(cheng)為負(fu)載調整率。性(xing)能(neng)優(you)良的光(guang)伏逆變(bian)器的電(dian)壓調整率應小于(yu)等于(yu)±3%，負載調整(zheng)率(lv)就小于等于±6%。

3、整機效率

整機(ji)效(xiao)(xiao)率(lv)表示(shi)光(guang)伏(fu)逆變器(qi)自身(shen)功率(lv)損耗的大(da)小。容量較大(da)的光(guang)伏(fu)逆變器(qi)還要給(gei)出滿負(fu)荷(he)工作和(he)低負(fu)荷(he)工作下的效(xiao)(xiao)率(lv)值。一般KW級(ji)以(yi)下(xia)的逆變器的效率應為(wei)80%~85%；10KW級的效率應為85%~90%；更大(da)功率(lv)的效率(lv)必(bi)須(xu)在90%~95%以(yi)上。逆變器效(xiao)(xiao)率高(gao)低(di)對光伏發(fa)電(dian)系統提高(gao)有(you)(you)效(xiao)(xiao)發(fa)電(dian)量和降低(di)發(fa)電(dian)成本(ben)有(you)(you)重要影(ying)響，因此選(xuan)用光伏逆變器要盡量進行比較，選(xuan)擇整(zheng)機效(xiao)(xiao)率高(gao)一些的產品。

4、啟動性能

光伏逆變器應保證在額(e)定負載下可(ke)靠啟(qi)動(dong)。高(gao)性(xing)能的光伏逆變器可(ke)以做到連續多次滿(man)負荷啟(qi)動(dong)而不損壞功(gong)率開(kai)關器件及(ji)其他電路(lu)。小型逆變器為了(le)自身安全(quan)，有時采(cai)用軟啟(qi)動(dong)或(huo)限流啟(qi)動(dong)措施(shi)或(huo)電路(lu)。

光伏產(chan)業從歐洲(zhou)，澳洲(zhou)，到現在的中國已(yi)經(jing)成了(le)熱門(men)行業，短短幾年內國內光伏逆(ni)變器生(sheng)產(chan)廠家如(ru)春(chun)筍(sun)般的誕生(sheng)，不過如(ru)何選擇太陽能逆(ni)變器這個還是有(you)一定的標準(zhun)。

首先考慮的是(shi)(shi)光伏電(dian)站(zhan)的規模(mo)，是(shi)(shi)家庭還是(shi)(shi)企(qi)(qi)業，不過在國(guo)內組建太陽能(neng)光伏電(dian)站(zhan)還是(shi)(shi)比較少，主要(yao)是(shi)(shi)房(fang)屋結構條件(jian)等(deng)限制(zhi)，無法安(an)裝太陽能(neng)電(dian)池(chi)板，廠房(fang)和(he)企(qi)(qi)業還是(shi)(shi)很有優勢(shi)。小型家庭光伏電(dian)站(zhan)主要(yao)是(shi)(shi)針對國(guo)外別(bie)墅安(an)裝。

其次(ci)考慮的(de)(de)是(shi)效(xiao)率(lv)。效(xiao)率(lv)說直接點(dian)就(jiu)是(shi)根發電量直接掛鉤，所以現在越來越多的(de)(de)光伏逆變器生產廠家對逆變器的(de)(de)效(xiao)率(lv)作為主要(yao)技術(shu)優勢來研(yan)發。

5、最后要考慮是否可靠

光(guang)(guang)伏并網(wang)(wang)發電(dian)(dian)(dian)(dian)系(xi)(xi)統是(shi)(shi)將(jiang)太陽能電(dian)(dian)(dian)(dian)池發出的(de)(de)(de)直(zhi)流(liu)電(dian)(dian)(dian)(dian)轉(zhuan)化為與電(dian)(dian)(dian)(dian)網(wang)(wang)電(dian)(dian)(dian)(dian)壓(ya)同(tong)頻(pin)同(tong)相的(de)(de)(de)交流(liu)電(dian)(dian)(dian)(dian)，并且實現既向(xiang)負載供電(dian)(dian)(dian)(dian)，又向(xiang)電(dian)(dian)(dian)(dian)網(wang)(wang)發電(dian)(dian)(dian)(dian)的(de)(de)(de)系(xi)(xi)統。光(guang)(guang)伏并網(wang)(wang)發電(dian)(dian)(dian)(dian)系(xi)(xi)統主(zhu)要(yao)由(you)(you)光(guang)(guang)伏陣(zhen)(zhen)列、并網(wang)(wang)逆變器、控制(zhi)器和繼電(dian)(dian)(dian)(dian)保護(hu)裝置組(zu)成。光(guang)(guang)伏陣(zhen)(zhen)列是(shi)(shi)光(guang)(guang)伏并網(wang)(wang)發電(dian)(dian)(dian)(dian)系(xi)(xi)統的(de)(de)(de)主(zhu)要(yao)部件，由(you)(you)其將(jiang)接(jie)收到(dao)的(de)(de)(de)太陽光(guang)(guang)能直(zhi)接(jie)轉(zhuan)換為電(dian)(dian)(dian)(dian)能。目前工程上應用(yong)的(de)(de)(de)光(guang)(guang)伏陣(zhen)(zhen)列一般是(shi)(shi)由(you)(you)一定(ding)數量(liang)的(de)(de)(de)晶(jing)體(ti)硅(gui)太陽能電(dian)(dian)(dian)(dian)池組(zu)件按照系(xi)(xi)統需(xu)要(yao)的(de)(de)(de)電(dian)(dian)(dian)(dian)壓(ya)的(de)(de)(de)要(yao)求串、并聯(lian)組(zu)成的(de)(de)(de)。