比例ASCO世格電磁閥開環-閉環復合控制算法

比(bi)例ASCO世格電磁閥開環-閉環復合控制算法

ASCO世格(ge)電磁(ci)(ci)閥(fa)為(wei)(wei)研究對象，以快速建(jian)立(li)(li)具有良好(hao)性(xing)(xing)能(neng)的(de)(de)通用(yong)控(kong)制(zhi)(zhi)算(suan)法為(wei)(wei)目標，以充分(fen)利用(yong)電磁(ci)(ci)閥(fa)的(de)(de)響(xiang)(xiang)應(ying)特(te)(te)(te)性(xing)(xing)為(wei)(wei)途(tu)徑(jing)，提出了(le)(le)(le)將(jiang)開(kai)(kai)環(huan)(huan)控(kong)制(zhi)(zhi)和(he)閉環(huan)(huan)控(kong)制(zhi)(zhi)相結合的(de)(de)開(kai)(kai)環(huan)(huan)-閉環(huan)(huan)復(fu)合控(kong)制(zhi)(zhi)算(suan)述(shu)了(le)(le)(le)控(kong)制(zhi)(zhi)算(suan)法的(de)(de)模型(xing)(xing)結構(gou)和(he)設(she)(she)計過(guo)程。不同(tong)于將(jiang)誤(wu)差(cha)(cha)作(zuo)為(wei)(wei)輸(shu)入的(de)(de)常(chang)規控(kong)制(zhi)(zhi)算(suan)法，復(fu)合控(kong)制(zhi)(zhi)算(suan)法同(tong)時將(jiang)目標值(zhi)和(he)誤(wu)差(cha)(cha)作(zuo)為(wei)(wei)控(kong)制(zhi)(zhi)器的(de)(de)輸(shu)入。以電磁(ci)(ci)閥(fa)響(xiang)(xiang)應(ying)特(te)(te)(te)性(xing)(xing)實驗(yan)為(wei)(wei)基礎，根(gen)據(ju)電磁(ci)(ci)閥(fa)的(de)(de)穩態(tai)特(te)(te)(te)性(xing)(xing)建(jian)立(li)(li)開(kai)(kai)環(huan)(huan)控(kong)制(zhi)(zhi)表，消除系統(tong)的(de)(de)穩態(tai)非線性(xing)(xing);根(gen)據(ju)電磁(ci)(ci)閥(fa)的(de)(de)瞬態(tai)特(te)(te)(te)性(xing)(xing)設(she)(she)計閉環(huan)(huan)控(kong)制(zhi)(zhi)器和(he)滯(zhi)后特(te)(te)(te)性(xing)(xing)預(yu)估修正模塊，降低模型(xing)(xing)誤(wu)差(cha)(cha)和(he)滯(zhi)后特(te)(te)(te)性(xing)(xing)的(de)(de)影響(xiang)(xiang)，提高動(dong)態(tai)響(xiang)(xiang)應(ying)性(xing)(xing)能(neng)。實驗(yan)結果驗(yan)證了(le)(le)(le)復(fu)合控(kong)制(zhi)(zhi)算(suan)法的(de)(de)控(kong)制(zhi)(zhi)精度、響(xiang)(xiang)應(ying)速度和(he)魯(lu)棒性(xing)(xing)。

在(zai)(zai)施肥、灌(guan)溉、噴藥、驅動(dong)、變速器等設備中廣泛應用比例電磁閥(fa)(fa)對壓力(li)或(huo)流量進行控(kong)(kong)制(zhi)。由(you)于比例閥(fa)(fa)在(zai)(zai)主要(yao)(yao)工(gong)作區間內具有良好的(de)(de)線性(xing)，當控(kong)(kong)制(zhi)性(xing)能(neng)(neng)要(yao)(yao)求(qiu)不高時，采用簡單的(de)(de)PID 控(kong)(kong)制(zhi)算法即能(neng)(neng)基本滿足要(yao)(yao)求(qiu)。隨(sui)著精(jing)準農業對控(kong)(kong)制(zhi)精(jing)度(du)、動(dong)態性(xing)能(neng)(neng)、全工(gong)況調(diao)節性(xing)能(neng)(neng)和穩定性(xing)的(de)(de)要(yao)(yao)求(qiu)逐漸(jian)提高，則需要(yao)(yao)設計性(xing)能(neng)(neng)更加的(de)(de)控(kong)(kong)制(zhi)器。

提(ti)高控(kong)(kong)(kong)(kong)制(zhi)性能的(de)(de)(de)措施主(zhu)要包括優化電磁(ci)閥結構和改進控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)兩(liang)個方(fang)面。在控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)方(fang)面，之前也發布的(de)(de)(de)很多文章中針對具體應用場合設計(ji)了不同(tong)的(de)(de)(de)控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)。為(wei)了在提(ti)高控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)性能的(de)(de)(de)同(tong)時(shi)，促進控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)的(de)(de)(de)模塊化和通(tong)用化，本(ben)文提(ti)出一種針對比(bi)例電磁(ci)閥控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)的(de)(de)(de)設計(ji)流(liu)(liu)(liu)程(cheng)，按照該流(liu)(liu)(liu)程(cheng)即可獲得具有良好控(kong)(kong)(kong)(kong)制(zhi)性能的(de)(de)(de)控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)，以某反比(bi)例溢流(liu)(liu)(liu)閥為(wei)例，論述控(kong)(kong)(kong)(kong)制(zhi)算法(fa)(fa)(fa)(fa)的(de)(de)(de)設計(ji)過程(cheng)和控(kong)(kong)(kong)(kong)制(zhi)效果(guo)。

1、電磁閥特(te)性實驗與建(jian)模

　　1.1、電磁(ci)閥特性實(shi)驗

　　以某反(fan)比(bi)例溢流(liu)閥(fa)作為控制對(dui)象，油泵(beng)(beng)由發(fa)動機驅動，通過調節占空比(bi)控制液壓(ya)(ya)(ya)缸的(de)壓(ya)(ya)(ya)力(li)(li)(li)。電磁閥(fa)特(te)性(xing)(xing)實驗包括穩態(tai)特(te)性(xing)(xing)實驗和瞬態(tai)特(te)性(xing)(xing)實驗。穩態(tai)壓(ya)(ya)(ya)力(li)(li)(li)主(zhu)(zhu)要影響(xiang)因素為占空比(bi)和油泵(beng)(beng)轉(zhuan)速(su)，部分實驗結果如(ru)(ru)圖1a 所(suo)示。穩態(tai)壓(ya)(ya)(ya)力(li)(li)(li)在主(zhu)(zhu)要壓(ya)(ya)(ya)力(li)(li)(li)范圍內線性(xing)(xing)度良好，具有明(ming)顯的(de)飽和特(te)性(xing)(xing)和回滯(zhi)特(te)性(xing)(xing)。占空比(bi)一定時，油泵(beng)(beng)轉(zhuan)速(su)越(yue)高，壓(ya)(ya)(ya)力(li)(li)(li)越(yue)大，當(dang)轉(zhuan)速(su)超(chao)過3000r/min時，其(qi)對(dui)壓(ya)(ya)(ya)力(li)(li)(li)的(de)影響(xiang)已不明(ming)顯。將(jiang)相互(hu)對(dui)應(ying)的(de)兩條(tiao)回滯(zhi)曲(qu)線進(jin)行平均(jun)，并做平滑處理，得到平均(jun)穩態(tai)壓(ya)(ya)(ya)力(li)(li)(li)特(te)性(xing)(xing)，如(ru)(ru)圖1b 所(suo)示。

(a)部分(fen)穩態壓(ya)力實驗結果(guo) (b)平均(jun)穩態壓(ya)力特性圖

　　瞬態特性實驗是(shi)測試不同轉速下(xia)占空比(bi)階躍(yue)變化時(shi)的壓力(li)(li)響應過程，包(bao)括階躍(yue)上升和(he)階躍(yue)下(xia)降兩(liang)個(ge)過程，結(jie)果(guo)如(ru)圖2 所(suo)示。可以看出，瞬態壓力(li)(li)變化過程有3 個(ge)特點：

　　①壓(ya)力的(de)響應延遲時間約(yue)為0.03s，并且與轉(zhuan)速無關。

　　②響(xiang)應過程中存(cun)在壓力波動(dong)，可(ke)近似為二階(jie)系統。

　　③不同轉(zhuan)速(su)下(xia)的壓力上升過程(cheng)略有差(cha)別，轉(zhuan)速(su)越(yue)高，響應速(su)度越(yue)快，但不同轉(zhuan)速(su)下(xia)的壓力下(xia)降過程(cheng)則基本重合。

(a)階(jie)躍上升 (b)階(jie)躍下降

4、結論

　　(1) 對比例ASCO世格(ge)電(dian)(dian)磁(ci)閥的(de)穩(wen)態(tai)(tai)和瞬態(tai)(tai)響應特(te)性(xing)進行實驗，將電(dian)(dian)磁(ci)閥的(de)響應特(te)性(xing)分為穩(wen)態(tai)(tai)飽和特(te)性(xing)、二階動態(tai)(tai)響應特(te)性(xing)和滯后特(te)性(xing)，建(jian)立電(dian)(dian)磁(ci)閥的(de)簡化傳(chuan)遞函(han)數模型。

　　(2) 結(jie)合以目標(biao)值為輸(shu)入(ru)的(de)(de)開環(huan)控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)和(he)以誤差(cha)(cha)為輸(shu)入(ru)的(de)(de)閉環(huan)控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)，形成開環(huan)-閉環(huan)復(fu)合控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)，可(ke)更有效地(di)利用系統(tong)信息。根據穩態特(te)性建立開環(huan)控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)表，閉環(huan)控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)器根據誤差(cha)(cha)對控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)量(liang)或控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)目標(biao)進行(xing)修正(zheng)，不同(tong)于以誤差(cha)(cha)作為輸(shu)入(ru)的(de)(de)常規控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)方法，復(fu)合控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)同(tong)時將目標(biao)值和(he)誤差(cha)(cha)作為控(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)器的(de)(de)輸(shu)入(ru)。

　　(3) 將復合控(kong)(kong)制(zhi)算法應用(yong)于電磁閥壓力控(kong)(kong)制(zhi)，根據電磁閥的(de)3 個特性分(fen)別設計了(le)開環(huan)控(kong)(kong)制(zhi)表、閉環(huan)控(kong)(kong)制(zhi)器和(he)(he)滯后特性預(yu)估(gu)修正模塊，制(zhi)定了(le)控(kong)(kong)制(zhi)算法的(de)設計流(liu)程。實驗和(he)(he)應用(yong)結果(guo)驗證了(le)開環(huan)-閉環(huan)復合控(kong)(kong)制(zhi)算法的(de)控(kong)(kong)制(zhi)精度(du)、響應速度(du)和(he)(he)魯(lu)棒(bang)性。

電(dian)(dian)(dian)(dian)(dian)控(kong)(kong)(kong)(kong)單(dan)(dan)(dan)體泵(beng)應(ying)(ying)用于柴油(you)(you)機上，是可(ke)滿足排放(fang)法規和改(gai)善燃(ran)油(you)(you)經濟性(xing)的(de)(de)(de)(de)時間控(kong)(kong)(kong)(kong)制式(shi)燃(ran)油(you)(you)噴射系統(tong)。高速(su)(su)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥是其關鍵(jian)部件之(zhi)一，它的(de)(de)(de)(de)快速(su)(su)響應(ying)(ying)直接(jie)影響了(le)噴油(you)(you)系統(tong)的(de)(de)(de)(de)噴油(you)(you)量、噴油(you)(you)定(ding)時等關鍵(jian)特性(xing)。電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)大小決定(ding)了(le)其快速(su)(su)響應(ying)(ying)性(xing)能。目前研究只限于對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)單(dan)(dan)(dan)因素影響分(fen)(fen)析，未分(fen)(fen)析全工(gong)況平(ping)(ping)面內各種(zhong)因素變(bian)化(hua)(hua)對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)影響和對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)貢(gong)獻程度(du)。本(ben)文在Ansoft軟件環境下建立電(dian)(dian)(dian)(dian)(dian)控(kong)(kong)(kong)(kong)單(dan)(dan)(dan)體泵(beng)高速(su)(su)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥三維有(you)限元仿(fang)真(zhen)計算模型，并(bing)(bing)試驗(yan)驗(yan)證了(le)仿(fang)真(zhen)模型的(de)(de)(de)(de)準(zhun)確性(xing)，然后應(ying)(ying)用仿(fang)真(zhen)模型研究了(le)電(dian)(dian)(dian)(dian)(dian)控(kong)(kong)(kong)(kong)單(dan)(dan)(dan)體泵(beng)高速(su)(su)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥全工(gong)況平(ping)(ping)面內鐵(tie)芯磁(ci)(ci)極長度(du)、線圈匝數(shu)、線圈位置、銜鐵(tie)厚度(du)、阻尼孔位置和大小等參(can)數(shu)變(bian)化(hua)(hua)對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)影響，并(bing)(bing)對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)變(bian)化(hua)(hua)進行量化(hua)(hua)分(fen)(fen)析，得出各參(can)數(shu)對(dui)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)影響的(de)(de)(de)(de)百(bai)分(fen)(fen)比量化(hua)(hua)指(zhi)標，從(cong)而得到全工(gong)況平(ping)(ping)面內影響電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)力(li)的(de)(de)(de)(de)關鍵(jian)參(can)數(shu)，為(wei)電(dian)(dian)(dian)(dian)(dian)磁(ci)(ci)閥的(de)(de)(de)(de)優化(hua)(hua)設計提供理(li)論指(zhi)導。

1、電(dian)磁(ci)閥結構組成和(he)工作(zuo)原理

　　電(dian)控(kong)(kong)(kong)單體泵(beng)電(dian)磁(ci)閥主要包(bao)括電(dian)磁(ci)鐵(tie)、銜(xian)(xian)(xian)鐵(tie)、控(kong)(kong)(kong)制(zhi)(zhi)閥桿(gan)、銜(xian)(xian)(xian)鐵(tie)復(fu)位彈簧、出油(you)(you)(you)堵頭等零部件。其中，電(dian)磁(ci)鐵(tie)主要由(you)鐵(tie)芯(xin)、勵磁(ci)線圈、封裝(zhuang)外殼(ke)等組成。通電(dian)后(hou)，電(dian)磁(ci)鐵(tie)吸合(he)銜(xian)(xian)(xian)鐵(tie)，拉動(dong)(dong)控(kong)(kong)(kong)制(zhi)(zhi)閥桿(gan)，關(guan)閉密封錐面，切(qie)斷燃(ran)(ran)油(you)(you)(you)回路(lu)，從而在泵(beng)腔(qiang)內(nei)建立起燃(ran)(ran)油(you)(you)(you)噴(pen)(pen)(pen)射(she)所需的(de)(de)(de)高壓;斷電(dian)后(hou)，復(fu)位彈簧迫使銜(xian)(xian)(xian)鐵(tie)推動(dong)(dong)控(kong)(kong)(kong)制(zhi)(zhi)閥桿(gan)復(fu)位，密封錐面被(bei)開啟，卸載泵(beng)腔(qiang)內(nei)的(de)(de)(de)高壓燃(ran)(ran)油(you)(you)(you)，停(ting)止燃(ran)(ran)油(you)(you)(you)噴(pen)(pen)(pen)射(she)。該(gai)方(fang)式實(shi)現了(le)對燃(ran)(ran)油(you)(you)(you)噴(pen)(pen)(pen)射(she)過(guo)程的(de)(de)(de)數字控(kong)(kong)(kong)制(zhi)(zhi)，改(gai)變了(le)傳統噴(pen)(pen)(pen)油(you)(you)(you)泵(beng)的(de)(de)(de)機(ji)械控(kong)(kong)(kong)制(zhi)(zhi)方(fang)式，對噴(pen)(pen)(pen)油(you)(you)(you)量和噴(pen)(pen)(pen)油(you)(you)(you)定(ding)時的(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)通過(guo)調節控(kong)(kong)(kong)制(zhi)(zhi)閥桿(gan)的(de)(de)(de)閉合(he)時間長度和閉合(he)時刻來實(shi)現。

電控單體泵(beng)及(ji)其電磁閥(fa)結構(gou)圖

5、結論

　　(1)驗證了(le)Ansoft建立的高速電磁(ci)閥(fa)三維有限元模型的準確(que)性，利用仿真模型得到了(le)電控(kong)單(dan)體泵電磁(ci)閥(fa)全工況(kuang)平面(mian)內各參數(shu)對電磁(ci)力的影響規律(lv)。