1.前言

    蓄電(dian)池的充(chong)(chong)電(dian)控(kong)制系(xi)統(tong)是(shi)個(ge)非線性[1]的、時變的、有干擾的、具(ju)有純(chun)滯后的控(kong)制系(xi)統(tong)[2]。在(zai)充(chong)(chong)放(fang)電(dian)過程中涉及到很多(duo)參數，如充(chong)(chong)電(dian)率、最大允(yun)許(xu)充(chong)(chong)電(dian)電(dian)流、內阻、出氣點電(dian)壓、溫度、壽命等。

   傳統(tong)的控(kong)制(zhi)(zhi)系統(tong)是(shi)建立在被(bei)控(kong)對象(xiang)精確數學(xue)(xue)模型(xing)基(ji)礎上的，如果被(bei)控(kong)對象(xiang)的數學(xue)(xue)模型(xing)很復雜或(huo)者數學(xue)(xue)模型(xing)無(wu)法(fa)建立，控(kong)制(zhi)(zhi)系統(tong)就較(jiao)難實(shi)現。蓄(xu)(xu)(xu)電(dian)池(chi)充(chong)電(dian)正(zheng)是(shi)屬于(yu)這種情況，由(you)于(yu)蓄(xu)(xu)(xu)電(dian)池(chi)的充(chong)電(dian)過程有自己獨(du)特的物理化學(xue)(xue)規(gui)律，因此考慮采用(yong)模糊控(kong)制(zhi)(zhi)技術來進行蓄(xu)(xu)(xu)電(dian)池(chi)的充(chong)電(dian)控(kong)制(zhi)(zhi) [3]。

   模(mo)糊(hu)控制[4]是(shi)(shi)以模(mo)糊(hu)集(ji)合(he)理論(lun)為基礎的(de)(de)控制手段，它是(shi)(shi)模(mo)糊(hu)系統(tong)理論(lun)、模(mo)糊(hu)技術與自動控制技術相(xiang)結合(he)的(de)(de)產物,出發(fa)點是(shi)(shi)操作人員(yuan)的(de)(de)控制經(jing)驗(yan)或相(xiang)關專家的(de)(de)知識，在設計(ji)(ji)中(zhong)不(bu)需(xu)要建立(li)被(bei)控對象(xiang)的(de)(de)精確(que)數學(xue)模(mo)型[5]，因而使得控制機(ji)理和策略易(yi)于接受與理解，設計(ji)(ji)簡單，便于應用。

2.模(mo)糊(hu)控(kong)制器(qi)的(de)結構及(ji)算法

   基于微控制器(qi)組成的模糊(hu)控制器(qi)包括模糊(hu)化接口、決策邏輯(ji)、知識(shi)庫和反模糊(hu)化接口四個(ge)部(bu)分，如圖1所示。

圖1模(mo)糊控制器的結構(gou)框圖

Fig.1 The structure diagram of fuzzy controller

   在進行模(mo)糊控制(zhi)(zhi)(zhi)算法(fa)設(she)計時，須首先考(kao)慮智能(neng)充電(dian)系統的(de)技術要(yao)求，體現智能(neng)充電(dian)控制(zhi)(zhi)(zhi)技術的(de)優勢，解決長期(qi)困擾(rao)蓄電(dian)池裝(zhuang)備中的(de)效率和壽(shou)命問題，所以(yi)應(ying)當(dang)提高智能(neng)充電(dian)控制(zhi)(zhi)(zhi)中對(dui)控制(zhi)(zhi)(zhi)量的(de)精度(du)；其次(ci)，模(mo)糊控制(zhi)(zhi)(zhi)算法(fa)必須高速可靠，對(dui)外部檢測(ce)得到的(de)物理(li)量要(yao)有非常快的(de)反應(ying)速度(du)。采用新型大存儲容量的(de)微控制(zhi)(zhi)(zhi)器解決使用查(cha)表法(fa)所帶(dai)來的(de)需要(yao)大容量內存的(de)問題。

3 模糊控(kong)制(zhi)器(qi)的設(she)計(ji)

3.1雙(shuang)輸入單輸出模糊(hu)控制器(qi)

    常見(jian)的模糊控(kong)(kong)制(zhi)器[6]根(gen)據輸(shu)(shu)入(ru)與輸(shu)(shu)出(chu)個數分為(wei)單輸(shu)(shu)入(ru)單輸(shu)(shu)出(chu)、雙輸(shu)(shu)入(ru)單輸(shu)(shu)出(chu)、多(duo)輸(shu)(shu)入(ru)單輸(shu)(shu)出(chu)和雙輸(shu)(shu)入(ru)多(duo)輸(shu)(shu)出(chu)等幾種(zhong)。平時應(ying)用較多(duo)的是雙輸(shu)(shu)入(ru)單輸(shu)(shu)出(chu)模糊控(kong)(kong)制(zhi)器。

圖(tu)2 雙輸(shu)入單輸(shu)出模(mo)糊控制(zhi)器方框圖(tu)

 Fig.2 The rectangular diagram of fuzzy cONtroller witch has two input units and one output unit

    圖(tu)2是(shi)雙輸(shu)(shu)(shu)入單輸(shu)(shu)(shu)出模(mo)(mo)(mo)糊(hu)(hu)控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)方框圖(tu)。其中屬于論(lun)域X的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)集合 取自系統(tong)誤差(cha)e的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)化(hua)，屬于論(lun)域Y的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)集合 取自系統(tong)誤差(cha)變化(hua)率 的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)化(hua)，二者構(gou)成模(mo)(mo)(mo)糊(hu)(hu)控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)二維(wei)輸(shu)(shu)(shu)入；屬于論(lun)域Z的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)集合 是(shi)反映控(kong)制(zhi)(zhi)量(liang)變化(hua)的(de)(de)(de)模(mo)(mo)(mo)糊(hu)(hu)控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)一維(wei)輸(shu)(shu)(shu)出，模(mo)(mo)(mo)糊(hu)(hu)控(kong)制(zhi)(zhi)器(qi)的(de)(de)(de)控(kong)制(zhi)(zhi)規則(ze)[7]通常(chang)由模(mo)(mo)(mo)糊(hu)(hu)條件(jian)語句if    and    then  來表(biao)達。

3.2精確量(liang)的模糊化

   模(mo)糊(hu)(hu)控(kong)制系(xi)(xi)統中(zhong)的被控(kong)對象狀態(tai)變(bian)化(hua)是連(lian)續(xu)的，系(xi)(xi)統給定(ding)值也(ye)是連(lian)續(xu)的,反映到模(mo)糊(hu)(hu)控(kong)制器(qi)輸入端的輸入量也(ye)必然是連(lian)續(xu)的。但模(mo)糊(hu)(hu)控(kong)制器(qi)由計算機構(gou)成，它(ta)只(zhi)能(neng)執行(xing)(xing)離(li)散(san)處理[7]。因此模(mo)糊(hu)(hu)控(kong)制器(qi)要求輸入量是離(li)散(san)模(mo)糊(hu)(hu)量，即論域是離(li)散(san)的。對連(lian)續(xu)論域要進行(xing)(xing)離(li)散(san)化(hua)。連(lian)續(xu)論域[8]經過量化(hua)后就成為一(yi)個離(li)散(san)論域[8]。

設(she)有連續(xu)論(lun)域(yu)[a，b]，而量化之(zhi)后的離散論(lun)域(yu)為 ，亦(yi)即將連續(xu)論(lun)域(yu)分為2n段，則存(cun)在系數(shu)

                                                                   （1）

   隨后(hou)，在求出每條(tiao)(tiao)規則的強度之(zhi)后(hou)，把相(xiang)互矛(mao)盾的規則中強度較小的舍去；把相(xiang)同(tong)規則合成一條(tiao)(tiao)規則，得(de)到最后(hou)控(kong)制規則基。

3.3.2根據學習算法生成控制(zhi)規則

   對(dui)被(bei)控(kong)(kong)對(dui)象執行手(shou)動控(kong)(kong)制(zhi)(zhi)(zhi)所得(de)到的(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)規(gui)則(ze)(ze)是(shi)較粗(cu)糙的(de)(de)，有(you)時還可(ke)(ke)能會出現(xian)控(kong)(kong)制(zhi)(zhi)(zhi)死區，一個(ge)控(kong)(kong)制(zhi)(zhi)(zhi)規(gui)則(ze)(ze)表中會出現(xian)空(kong)項,這是(shi)不能滿足實際控(kong)(kong)制(zhi)(zhi)(zhi)要求的(de)(de)。為了取得(de)更滿意的(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)效果，可(ke)(ke)以對(dui)原始的(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)規(gui)則(ze)(ze)進(jin)(jin)行改進(jin)(jin)。這時，應(ying)以粗(cu)糙的(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)規(gui)則(ze)(ze)為基礎，通過仿真(zhen)實驗和系統調試加以完善。

4.模糊智能充電系統的工作原(yuan)理及結構

   智能充電(dian)(dian)(dian)(dian)(dian)(dian)系統主要(yao)由充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)源和(he)(he)單片(pian)機(ji)控制(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)路兩部(bu)分組(zu)成。220V的(de)(de)(de)交流(liu)(liu)(liu)市電(dian)(dian)(dian)(dian)(dian)(dian)經整流(liu)(liu)(liu)濾波(bo)電(dian)(dian)(dian)(dian)(dian)(dian)路變為脈動的(de)(de)(de)310V高壓(ya)直流(liu)(liu)(liu)。然后經DC-DC變換電(dian)(dian)(dian)(dian)(dian)(dian)路（脈沖功(gong)率變壓(ya)器）變為充電(dian)(dian)(dian)(dian)(dian)(dian)所需的(de)(de)(de)60V直流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。為了保(bao)證(zheng)輸(shu)(shu)出電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)(de)(de)穩(wen)定性，采用(yong)了UC3842對60V直流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)進行穩(wen)壓(ya)。二次(ci)斬(zhan)波(bo)電(dian)(dian)(dian)(dian)(dian)(dian)路主要(yao)由MOSFET管(guan)、電(dian)(dian)(dian)(dian)(dian)(dian)感、電(dian)(dian)(dian)(dian)(dian)(dian)容和(he)(he)二極管(guan)組(zu)成，輸(shu)(shu)出24-36V的(de)(de)(de)充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。控制(zhi)(zhi)部(bu)分采用(yong)C504單片(pian)機(ji)，通過對蓄電(dian)(dian)(dian)(dian)(dian)(dian)池端(duan)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)信號的(de)(de)(de)采集(ji)、分析(xi)處理、模(mo)糊推理[8]、模(mo)糊決(jue)策等，控制(zhi)(zhi)二次(ci)斬(zhan)波(bo)電(dian)(dian)(dian)(dian)(dian)(dian)路中的(de)(de)(de)MOSFET管(guan)的(de)(de)(de)通斷時間來控制(zhi)(zhi)充電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。控制(zhi)(zhi)部(bu)分還(huan)包括(kuo)對電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)和(he)(he)溫度的(de)(de)(de)采集(ji)以(yi)及電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)和(he)(he)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)(de)顯示(shi)。總體結構如圖3所示(shi)。

圖3 智能充電系統總體結構框圖

5結論

  蓄(xu)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)充(chong)(chong)(chong)放(fang)電(dian)(dian)(dian)過程(cheng)是一個復雜的(de)(de)過程(cheng)，要用精確數學模(mo)型(xing)對蓄(xu)電(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)的(de)(de)控(kong)(kong)制則(ze)有(you)相當的(de)(de)難(nan)度。蓄(xu)電(dian)(dian)(dian)池(chi)(chi)的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)控(kong)(kong)制系統是個非線性的(de)(de)、時(shi)變的(de)(de)、有(you)干擾的(de)(de)、具有(you)純滯后的(de)(de)控(kong)(kong)制系統，在充(chong)(chong)(chong)放(fang)電(dian)(dian)(dian)過程(cheng)中涉(she)及(ji)到很多參數，如充(chong)(chong)(chong)電(dian)(dian)(dian)率、最大(da)允許充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)、內阻(zu)、出氣(qi)點電(dian)(dian)(dian)壓、溫度、壽命等(deng)。

   作(zuo)者創新點為(wei)：

(1) 隸屬(shu)函(han)數(shu) 的形狀，對控制效果(guo)影響較大。窄型隸屬(shu)函(han)數(shu)，反映(ying)模(mo)糊集(ji)合(he)具(ju)(ju)(ju)有(you)高(gao)分辨(bian)(bian)特(te)性。如(ru)果(guo)系(xi)(xi)統(tong)(tong)誤差(cha)，采(cai)(cai)用(yong)高(gao)分辨(bian)(bian)率(lv)模(mo)糊集(ji)合(he)，則誤差(cha)控制的靈(ling)敏(min)度(du)就會提高(gao)。在系(xi)(xi)統(tong)(tong)誤差(cha)較大的范圍內，采(cai)(cai)用(yong)具(ju)(ju)(ju)有(you)低(di)分辨(bian)(bian)率(lv)隸屬(shu)函(han)數(shu)的模(mo)糊集(ji)合(he)；而在系(xi)(xi)統(tong)(tong)誤差(cha)較小(xiao)，或接(jie)近(jin)于零時(shi)，宜(yi)采(cai)(cai)用(yong)具(ju)(ju)(ju)有(you)高(gao)分辨(bian)(bian)率(lv)隸屬(shu)函(han)數(shu)的模(mo)糊集(ji)合(he)。

(2)在定義某一語言變量，如誤(wu)差、誤(wu)差變化率和控制量變化的(de)(de)全部(bu)集合(he)時，要考慮其(qi)對論(lun)域[-n,+n]的(de)(de)覆蓋程(cheng)度，語言變量的(de)(de)全部(bu)模糊集合(he)所(suo)包含的(de)(de)非零隸屬度對應(ying)的(de)(de)論(lun)域元素(su)個數，應(ying)是模糊集合(he)總數的(de)(de)3-4倍。

（3）查表法作為模糊控制算法有表格結構單一，修改繁瑣，缺乏靈活性的缺點。針對使用查表法作為模糊控制算法暴露的缺點，在硬件設計中與以補償，加入了一片X5045電可擦除芯片，將模糊控制表格中的數據存儲于微控制器外部存儲空間中，基本上克服了這個缺點。