一、BMS電池管理系統中的各種算法簡介
BMS電池管理系統是一種用于電池組中的單個電池管理的系統,以確保其安全性、壽命和性能,在BMS電池管理系統中(zhong)涉及到了許多算(suan)法,具體有:
1、最大功率點追蹤算法
最(zui)(zui)大(da)(da)功率(lv)點(dian)(dian)追(zhui)蹤算法是一種用于(yu)(yu)優(you)化太(tai)陽(yang)能電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)板(ban)輸(shu)出(chu)(chu)功率(lv)的(de)算法。在BMS電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)管理系(xi)統中,最(zui)(zui)大(da)(da)功率(lv)點(dian)(dian)追(zhui)蹤算法也被(bei)用于(yu)(yu)優(you)化電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)輸(shu)出(chu)(chu)功率(lv),以延長(chang)電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)壽命和提高電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)性(xing)能。該算法通(tong)常采(cai)用迭代(dai)法求(qiu)解,在每次迭代(dai)中,計算當前電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)組的(de)輸(shu)出(chu)(chu)功率(lv)并根據輸(shu)出(chu)(chu)功率(lv)的(de)變化調(diao)整(zheng)電(dian)(dian)池(chi)(chi)(chi)(chi)(chi)組的(de)工作狀態,以找(zhao)到(dao)最(zui)(zui)大(da)(da)功率(lv)點(dian)(dian)。
最大(da)(da)功(gong)(gong)率(lv)點(dian)追蹤(zong)算(suan)法(fa)(fa)的核(he)心是(shi)找(zhao)到電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)組輸出(chu)功(gong)(gong)率(lv)與電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)組工作狀態之(zhi)間的關系(xi)。在實際(ji)應用(yong)中(zhong),最大(da)(da)功(gong)(gong)率(lv)點(dian)追蹤(zong)算(suan)法(fa)(fa)通常采用(yong)PerturbandObserve(P&O)算(suan)法(fa)(fa)或IncrementalConductance(IC)算(suan)法(fa)(fa)。其中(zhong),P&O算(suan)法(fa)(fa)是(shi)一(yi)種基(ji)于(yu)光強變(bian)化的算(suan)法(fa)(fa),它通過改變(bian)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓并觀察電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)輸出(chu)功(gong)(gong)率(lv)的變(bian)化,來尋找(zhao)最大(da)(da)功(gong)(gong)率(lv)點(dian)。IC算(suan)法(fa)(fa)則是(shi)一(yi)種基(ji)于(yu)導(dao)數的算(suan)法(fa)(fa),它通過計算(suan)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓和電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)流之(zhi)間的導(dao)數來確定最大(da)(da)功(gong)(gong)率(lv)點(dian)。
2、SOC計算算法
SOC(StateofCharge)是電(dian)(dian)池(chi)組(zu)(zu)中(zhong)電(dian)(dian)池(chi)當前(qian)充電(dian)(dian)狀(zhuang)態的指(zhi)標。在BMS電(dian)(dian)池(chi)管理系統中(zhong),SOC計算(suan)算(suan)法被用于確定電(dian)(dian)池(chi)組(zu)(zu)的當前(qian)充電(dian)(dian)狀(zhuang)態,以(yi)避免電(dian)(dian)池(chi)過充或欠充,延(yan)長電(dian)(dian)池(chi)壽命和提高電(dian)(dian)池(chi)性能。
在實際應用中(zhong),SOC計(ji)算算法(fa)(fa)通(tong)常采用開路電(dian)壓(ya)法(fa)(fa)(OCV)或卡(ka)爾曼濾(lv)波器(qi)法(fa)(fa)進(jin)行計(ji)算。其中(zhong),OCV法(fa)(fa)是(shi)一種基于(yu)電(dian)池開路電(dian)壓(ya)的(de)(de)計(ji)算方(fang)法(fa)(fa),它通(tong)過測(ce)(ce)量電(dian)池組的(de)(de)開路電(dian)壓(ya)來確定電(dian)池組的(de)(de)SOC。卡(ka)爾曼濾(lv)波器(qi)法(fa)(fa)則是(shi)一種基于(yu)狀態估計(ji)的(de)(de)算法(fa)(fa),它通(tong)過對(dui)電(dian)池組的(de)(de)充電(dian)和(he)(he)放電(dian)狀態進(jin)行預測(ce)(ce)和(he)(he)校正(zheng),來估計(ji)電(dian)池組的(de)(de)SOC。
3、SOH評估算法
SOH(StateofHealth)是電(dian)池(chi)組(zu)的健(jian)康(kang)狀(zhuang)況指(zhi)標,它反映了(le)電(dian)池(chi)組(zu)的壽(shou)命和性能(neng)。在BMS電(dian)池(chi)管理系(xi)統中,SOH評(ping)(ping)估(gu)算(suan)法被用(yong)(yong)于評(ping)(ping)估(gu)電(dian)池(chi)組(zu)的健(jian)康(kang)狀(zhuang)況,以幫助用(yong)(yong)戶了(le)解電(dian)池(chi)組(zu)的剩余壽(shou)命和性能(neng)表現。
在(zai)實際應用中(zhong),SOH評(ping)(ping)估(gu)算法(fa)(fa)(fa)通常采用電(dian)(dian)(dian)(dian)化(hua)(hua)學(xue)(xue)阻抗譜法(fa)(fa)(fa)(EIS)或數(shu)學(xue)(xue)建模(mo)(mo)法(fa)(fa)(fa)進(jin)行評(ping)(ping)估(gu)。其中(zhong),EIS法(fa)(fa)(fa)是一(yi)種基(ji)于電(dian)(dian)(dian)(dian)化(hua)(hua)學(xue)(xue)阻抗譜的(de)(de)(de)方(fang)法(fa)(fa)(fa),它通過對電(dian)(dian)(dian)(dian)池(chi)(chi)組進(jin)行小信號擾動,測量電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)電(dian)(dian)(dian)(dian)化(hua)(hua)學(xue)(xue)阻抗譜,并根據阻抗譜的(de)(de)(de)變化(hua)(hua)來(lai)評(ping)(ping)估(gu)電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)健康(kang)狀(zhuang)況。數(shu)學(xue)(xue)建模(mo)(mo)法(fa)(fa)(fa)則是一(yi)種基(ji)于電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)數(shu)學(xue)(xue)模(mo)(mo)型進(jin)行評(ping)(ping)估(gu)的(de)(de)(de)方(fang)法(fa)(fa)(fa),它通過建立電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)數(shu)學(xue)(xue)模(mo)(mo)型,模(mo)(mo)擬電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)工(gong)作過程,并根據模(mo)(mo)型的(de)(de)(de)預測結果來(lai)評(ping)(ping)估(gu)電(dian)(dian)(dian)(dian)池(chi)(chi)組的(de)(de)(de)健康(kang)狀(zhuang)況。
4、充放電控制算法
充(chong)(chong)(chong)放電(dian)控制(zhi)算法(fa)(fa)是BMS電(dian)池(chi)(chi)管(guan)理系統中(zhong)的核心算法(fa)(fa)之一,它用于控制(zhi)電(dian)池(chi)(chi)組(zu)的充(chong)(chong)(chong)放電(dian)過程,以確保電(dian)池(chi)(chi)組(zu)的安全性和壽命。在實際(ji)應用中(zhong),充(chong)(chong)(chong)放電(dian)控制(zhi)算法(fa)(fa)通常(chang)采用PID控制(zhi)器或模糊(hu)控制(zhi)器進行控制(zhi)。
其中,PID控制(zhi)器(qi)是(shi)一種基于誤差、積分(fen)和(he)微分(fen)的(de)控制(zhi)器(qi),它通(tong)過(guo)調(diao)整控制(zhi)器(qi)的(de)參數,使得電(dian)(dian)池組的(de)充放電(dian)(dian)電(dian)(dian)流和(he)電(dian)(dian)壓穩定在設定值附近。模糊控制(zhi)器(qi)則是(shi)一種基于模糊邏(luo)輯的(de)控制(zhi)器(qi),它通(tong)過(guo)建立模糊規則和(he)模糊推(tui)理,來實現電(dian)(dian)池組的(de)充放電(dian)(dian)控制(zhi)。
5、健康預警算法
健康預警(jing)算法(fa)是(shi)BMS電(dian)池管理系統中的另一種重(zhong)要算法(fa),它用于預測(ce)電(dian)池組的故障(zhang)和壽命(ming),以提前(qian)采(cai)取措施進行(xing)(xing)維護。在實際應用中,健康預警(jing)算法(fa)通(tong)常采(cai)用神經網(wang)絡、遺傳算法(fa)或支持(chi)向量機進行(xing)(xing)預測(ce)。
其中(zhong),神經網絡是(shi)一種(zhong)基(ji)(ji)于(yu)人工(gong)神經元(yuan)的(de)模(mo)型(xing),它通(tong)過(guo)訓練神經網絡的(de)權值和偏(pian)置(zhi),來實現(xian)電(dian)池(chi)組故障和壽(shou)命的(de)預(yu)測。遺傳算法則(ze)是(shi)一種(zhong)基(ji)(ji)于(yu)自(zi)然選擇適應度(du)高(gao)的(de)個(ge)體,不斷(duan)迭代尋找最優解。支持向量機則(ze)是(shi)一種(zhong)基(ji)(ji)于(yu)統計學習理論的(de)模(mo)型(xing),它通(tong)過(guo)構(gou)建最優的(de)分(fen)類超平面(mian),來實現(xian)電(dian)池(chi)組故障和壽(shou)命的(de)預(yu)測。
6、優化算法
優(you)化算(suan)法是BMS電池管理(li)系統中(zhong)的重要算(suan)法之一,它用(yong)于優(you)化電池組的性能和壽(shou)命,以滿足用(yong)戶的需求。在(zai)實際應用(yong)中(zhong),優(you)化算(suan)法通(tong)常采用(yong)遺傳(chuan)算(suan)法、粒(li)子(zi)群(qun)算(suan)法或模(mo)擬退火算(suan)法進行優(you)化。
其中(zhong),遺傳算法是(shi)一種(zhong)基于自然選擇和遺傳機制的(de)優(you)化算法,它通過(guo)(guo)模(mo)(mo)(mo)擬自然進化過(guo)(guo)程(cheng),不斷迭代(dai)尋找最優(you)解。粒子群算法則是(shi)一種(zhong)基于群體智能的(de)優(you)化算法,它通過(guo)(guo)模(mo)(mo)(mo)擬鳥(niao)群飛行的(de)過(guo)(guo)程(cheng),不斷迭代(dai)尋找最優(you)解。模(mo)(mo)(mo)擬退火(huo)算法則是(shi)一種(zhong)基于模(mo)(mo)(mo)擬退火(huo)過(guo)(guo)程(cheng)的(de)優(you)化算法,它通過(guo)(guo)模(mo)(mo)(mo)擬金屬退火(huo)的(de)過(guo)(guo)程(cheng),不斷迭代(dai)尋找最優(you)解。
7、數據處理算法
數據處(chu)理(li)(li)算(suan)法(fa)(fa)是BMS電(dian)池管理(li)(li)系統中的(de)另一種重要算(suan)法(fa)(fa),它用(yong)于(yu)處(chu)理(li)(li)電(dian)池組的(de)數據,以提取有用(yong)的(de)信息和(he)特(te)征。在(zai)實際應(ying)用(yong)中,數據處(chu)理(li)(li)算(suan)法(fa)(fa)通常采用(yong)濾波算(suan)法(fa)(fa)、降(jiang)維(wei)算(suan)法(fa)(fa)或特(te)征提取算(suan)法(fa)(fa)進行處(chu)理(li)(li)。
其(qi)中,濾波算法(fa)是(shi)一種(zhong)基(ji)于(yu)數字(zi)信(xin)(xin)號處理的算法(fa),它(ta)通(tong)過(guo)對電池組的信(xin)(xin)號進行濾波,去(qu)除(chu)噪聲和(he)(he)干擾,提取(qu)有用的信(xin)(xin)息。降(jiang)維算法(fa)則是(shi)一種(zhong)基(ji)于(yu)數據(ju)挖掘的算法(fa),它(ta)通(tong)過(guo)降(jiang)低數據(ju)的維度,減少數據(ju)量和(he)(he)復(fu)雜度,提高數據(ju)的可處理性和(he)(he)效(xiao)率。特(te)征(zheng)提取(qu)算法(fa)則是(shi)一種(zhong)基(ji)于(yu)模(mo)式(shi)識別(bie)(bie)的算法(fa),它(ta)通(tong)過(guo)提取(qu)數據(ju)的特(te)征(zheng),識別(bie)(bie)出(chu)數據(ju)中的模(mo)式(shi)和(he)(he)規律(lv),從而實現(xian)數據(ju)的分(fen)類和(he)(he)識別(bie)(bie)。
二、電池管理系統計算SOC的算法有哪些
電池管理系統中,SOC的計算是核心,SOC,全稱是StateofCharge,即電池荷電狀態,也叫剩余電量,常用百分數表示,由于電池復雜的化學特性導致SOC估算出現誤差,因此電池管理系統計算SOC的算法通常是(shi)估算,常用的算法有三種:
1、基于內阻補償的開路電壓法
開路(lu)電(dian)(dian)壓法(fa)(OCV)是(shi)最早的(de)電(dian)(dian)池容(rong)量測試方(fang)法(fa)之(zhi)(zhi)一,開路(lu)電(dian)(dian)壓法(fa)是(shi)根據電(dian)(dian)池的(de)開路(lu)電(dian)(dian)壓與(yu)電(dian)(dian)池內部鋰離(li)子濃度之(zhi)(zhi)間的(de)變化關(guan)系(xi),間接(jie)地(di)擬合出它與(yu)電(dian)(dian)池SOC之(zhi)(zhi)間的(de)一一對應關(guan)系(xi)。
開路電(dian)(dian)壓(ya)(ya)法簡單便(bian)捷,但是(shi)估(gu)算的精度(du)并不(bu)高。該方法只(zhi)能(neng)在(zai)電(dian)(dian)池(chi)(chi)長時間(jian)靜置狀態下(xia)估(gu)算SOC,當電(dian)(dian)池(chi)(chi)有(you)電(dian)(dian)流(liu)通過(guo)時,電(dian)(dian)池(chi)(chi)內阻產生的壓(ya)(ya)降會(hui)影響SOC估(gu)算精度(du)。同時電(dian)(dian)池(chi)(chi)存在(zai)電(dian)(dian)壓(ya)(ya)平臺,特別是(shi)磷酸鐵鋰電(dian)(dian)池(chi)(chi),在(zai)SOC30%-80%期間(jian),端(duan)電(dian)(dian)壓(ya)(ya)和SOC曲線(xian)近似(si)為直線(xian),這種情況下(xia)SOC的估(gu)算誤差會(hui)放大。
基于以上問題(ti),設計人員對開路(lu)電(dian)(dian)壓法(fa)做了(le)(le)補充,引入(ru)了(le)(le)電(dian)(dian)池內阻進行(xing)校正,準(zhun)確估(gu)算OCV。當電(dian)(dian)池通過(guo)(guo)電(dian)(dian)流時,通過(guo)(guo)將實際測(ce)得的電(dian)(dian)池端電(dian)(dian)壓減去I*R來(lai)校正負載下的電(dian)(dian)壓,然后使用校正電(dian)(dian)壓來(lai)獲得當前的SOC。
基于內阻補償的(de)開路電壓法提(ti)升了SOC的(de)估算(suan)精度,但是實際應(ying)用時(shi)由(you)于其復(fu)雜的(de)電化學特性,電池(chi)電壓不會立(li)即對負載的(de)變(bian)化作(zuo)出反應(ying),而(er)是有一(yi)定延(yan)遲。該延(yan)遲與電池(chi)電壓響應(ying)的(de)時(shi)間常數(shu)相關聯,范圍從毫秒(miao)到數(shu)千秒(miao)。同(tong)時(shi)電池(chi)的(de)內部阻抗(kang)(kang)在(zai)不同(tong)條件下(xia)變(bian)化較大,因此(ci)SOC的(de)精準估算(suan)依賴于阻抗(kang)(kang)的(de)精準估算(suan)。
2、安時法(庫倫計數法)
經(jing)典的(de)(de)(de)SOC估算一般采用安時(shi)積(ji)(ji)分法(fa)(也(ye)叫電(dian)(dian)(dian)流積(ji)(ji)分法(fa)或者庫(ku)侖計數法(fa))。即電(dian)(dian)(dian)池(chi)(chi)(chi)充放電(dian)(dian)(dian)過程中,通過累積(ji)(ji)充進(jin)和放出的(de)(de)(de)電(dian)(dian)(dian)量來估算SOC。充電(dian)(dian)(dian)時(shi),進(jin)入電(dian)(dian)(dian)池(chi)(chi)(chi)的(de)(de)(de)庫(ku)侖全部留在電(dian)(dian)(dian)池(chi)(chi)(chi)中,放電(dian)(dian)(dian)時(shi)全部流出的(de)(de)(de)電(dian)(dian)(dian)量導(dao)致SOC的(de)(de)(de)下降(jiang)。
SOCnow=SOCpast-(Inow*t)/Qmax
安(an)時(shi)積分(fen)法SOC估算精(jing)度(du)高于開路電(dian)(dian)壓(ya)法,但是(shi)該算法只(zhi)是(shi)單(dan)純(chun)的(de)從外部記錄(lu)流(liu)(liu)(liu)入和流(liu)(liu)(liu)出的(de)電(dian)(dian)池電(dian)(dian)量(liang)(liang),忽略(lve)了電(dian)(dian)池內部狀態的(de)變(bian)化。由于不(bu)(bu)同(tong)的(de)電(dian)(dian)池模型有不(bu)(bu)同(tong)的(de)自放(fang)電(dian)(dian)率,這也取決于電(dian)(dian)池的(de)SOC、溫度(du)和循環歷史,準(zhun)確的(de)自放(fang)電(dian)(dian)建模需(xu)要花費(fei)大(da)量(liang)(liang)的(de)時(shi)間(jian)收集數據,而且仍然相(xiang)當(dang)不(bu)(bu)精(jing)確。同(tong)時(shi)電(dian)(dian)流(liu)(liu)(liu)測(ce)量(liang)(liang)不(bu)(bu)準(zhun),造成SOC計算誤(wu)差(cha)會不(bu)(bu)斷累積,需(xu)要定期不(bu)(bu)斷校準(zhun)。而且在電(dian)(dian)池長時(shi)間(jian)不(bu)(bu)活動或放(fang)電(dian)(dian)電(dian)(dian)流(liu)(liu)(liu)變(bian)化很(hen)大(da)的(de)應用中(zhong),庫倫積分(fen)法會產生一定誤(wu)差(cha)。
3、電壓電流混合算法
由于(yu)開路(lu)電壓法在(zai)實際工況下并(bing)不(bu)實用,而安時(shi)積分法存在(zai)誤差,并(bing)且(qie)隨著(zhu)使(shi)用時(shi)間的增加誤差會繼續放大(da)。因此大(da)量設計人(ren)員(yuan)將開路(lu)電壓法與其他方法結合起來,共同進行SOC的預(yu)測(ce)。