恒通源告訴你光伏逆變器MPPT多路追蹤究竟是什么!
MPPT是逆變器非常核心的技術,MPPT電壓在進行光伏電站設計時一項非常關鍵的參數,MPPT控(kong)(kong)制(zhi)器(qi)的(de)全(quan)稱“最大功率點跟蹤”(Maximum Power Point Tracking)太(tai)陽(yang)(yang)能(neng)控(kong)(kong)制(zhi)器(qi),是傳統(tong)(tong)太(tai)陽(yang)(yang)能(neng)充放電(dian)(dian)(dian)控(kong)(kong)制(zhi)器(qi)的(de)升級換代產品。MPPT控(kong)(kong)制(zhi)器(qi)能(neng)夠實時(shi)偵(zhen)測太(tai)陽(yang)(yang)能(neng)板的(de)發電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya),并追蹤最高電(dian)(dian)(dian)壓(ya)電(dian)(dian)(dian)流值(VI),使系(xi)統(tong)(tong)以(yi)最大功率輸出對蓄(xu)電(dian)(dian)(dian)池充電(dian)(dian)(dian)。應用于太(tai)陽(yang)(yang)能(neng)光(guang)伏系(xi)統(tong)(tong)中(zhong),協調太(tai)陽(yang)(yang)能(neng)電(dian)(dian)(dian)池板、蓄(xu)電(dian)(dian)(dian)池、負載的(de)工(gong)作,是光(guang)伏系(xi)統(tong)(tong)的(de)大腦。
MPPT的作用是什么?
由于太陽能電池收到光(guang)強以(yi)及環境(jing)等外(wai)界因素(su)的(de)(de)影(ying)響,其輸出(chu)功率(lv)(lv)是變(bian)化(hua)的(de)(de),光(guang)強發出(chu)的(de)(de)電就(jiu)多,帶MPPT最大功率(lv)(lv)跟蹤的(de)(de)逆變(bian)器就(jiu)是為了充分(fen)的(de)(de)利用(yong)太陽能電池,使之運行在最大功率(lv)(lv)點。也就(jiu)是說(shuo)在太陽輻射不變(bian)的(de)(de)情(qing)況(kuang)下,有MPPT后的(de)(de)輸出(chu)功率(lv)(lv)會比有MPPT前的(de)(de)要高,這就(jiu)是MPPT的(de)(de)作(zuo)用(yong)所(suo)在。
就(jiu)假設說(shuo)MPPT還沒開(kai)(kai)始跟蹤(zong)(zong),這時組(zu)件輸(shu)出(chu)電(dian)壓是500V,然后(hou)MPPT開(kai)(kai)始跟蹤(zong)(zong)之后(hou),就(jiu)開(kai)(kai)始通(tong)過內部(bu)的(de)電(dian)路(lu)(lu)結構(gou)調(diao)節回路(lu)(lu)上的(de)電(dian)阻(zu),以(yi)改變組(zu)件輸(shu)出(chu)電(dian)壓,同時改變輸(shu)出(chu)電(dian)流,一(yi)直到輸(shu)出(chu)功率最(zui)大(假設是550V最(zui)大),此(ci)后(hou)就(jiu)不(bu)(bu)斷(duan)得跟蹤(zong)(zong),這樣一(yi)來也就(jiu)是說(shuo)在太陽輻射不(bu)(bu)變的(de)情(qing)況下(xia),組(zu)件在550V的(de)輸(shu)出(chu)電(dian)壓情(qing)況,輸(shu)出(chu)功率會比500V時要(yao)高,這就(jiu)是MPPT的(de)作用。
最大功率點跟蹤的原理
隨著電(dian)(dian)子(zi)技(ji)術(shu)的(de)(de)發展,當前(qian)太陽能電(dian)(dian)池陣列的(de)(de)MPPT控制(zhi)一般是通過DC/DC變換電(dian)(dian)路(lu)來完(wan)成的(de)(de)。其原(yuan)理框圖如下圖所示。
光(guang)伏電(dian)(dian)池(chi)陣(zhen)列(lie)與負載通過DC/DC電(dian)(dian)路連接,最大功率跟蹤(zong)裝(zhuang)置不斷(duan)檢測光(guang)伏陣(zhen)列(lie)的(de)電(dian)(dian)流電(dian)(dian)壓(ya)變化(hua),并根據其(qi)變化(hua)對DC/DC變換(huan)器的(de)PWM驅動信號占(zhan)空比進行調(diao)節。
MPPT系統原理(li)框圖(tu)
對于線(xian)性(xing)電(dian)(dian)(dian)路來說(shuo),當負(fu)載電(dian)(dian)(dian)阻等于電(dian)(dian)(dian)源(yuan)的內(nei)阻時,電(dian)(dian)(dian)源(yuan)即有最(zui)大(da)功率輸出(chu)。雖然光(guang)伏(fu)(fu)電(dian)(dian)(dian)池(chi)和DC/DC轉換電(dian)(dian)(dian)路都(dou)是強非線(xian)性(xing)的,然而在極(ji)短的時間內(nei),可以認為是線(xian)性(xing)電(dian)(dian)(dian)路。因此(ci),只要調節DC-DC轉換電(dian)(dian)(dian)路的等效電(dian)(dian)(dian)阻使(shi)它始終(zhong)等于光(guang)伏(fu)(fu)電(dian)(dian)(dian)池(chi)的內(nei)阻,就可以實現(xian)光(guang)伏(fu)(fu)電(dian)(dian)(dian)池(chi)的最(zui)大(da)輸出(chu),也就實現(xian)了(le)光(guang)伏(fu)(fu)電(dian)(dian)(dian)池(chi)的MPPT。
目前業內已經認識到了逆變器多MPPT通道的重要性,多MPPT的組串逆變器已經被廣泛的認可。華為組串式逆變器多達4路MPPT,可顯(xian)著提(ti)(ti)(ti)升發電(dian)量。深圳恒通源作為(wei)(wei)華(hua)(hua)為(wei)(wei)智能光伏授權經銷商,不(bu)僅(jin)能為(wei)(wei)廣(guang)大(da)客戶提(ti)(ti)(ti)供華(hua)(hua)為(wei)(wei)逆變器等系列產品,還能為(wei)(wei)客戶提(ti)(ti)(ti)供專業的技術(shu)支持(chi)及周到的售后服務!