真(zhen)空度真(zhen)空開關測試儀測算原理(li) 工作原理(li)

本儀(yi)器采用磁(ci)(ci)控放(fang)電(dian)(dian)法(fa)進行測量。將真空開(kai)關(guan)滅(mie)弧(hu)(hu)室(shi)的兩觸頭拉開(kai)一定的距離(li)，施加電(dian)(dian)場(chang)脈沖高壓，將滅(mie)弧(hu)(hu)室(shi)置(zhi)于螺(luo)線(xian)管(guan)圈內或將新(xin)型(xing)電(dian)(dian)磁(ci)(ci)線(xian)圈置(zhi)于滅(mie)弧(hu)(hu)室(shi)外側(ce)，向線(xian)圈通(tong)以大電(dian)(dian)流，從而在滅(mie)弧(hu)(hu)室(shi)內產生與(yu)高壓同步的脈沖磁(ci)(ci)場(chang)。這樣(yang)，在脈沖強(qiang)磁(ci)(ci)場(chang)和(he)強(qiang)電(dian)(dian)場(chang)的作用下，滅(mie)弧(hu)(hu)室(shi)中的帶電(dian)(dian)離(li)子(zi)作螺(luo)旋運動，并與(yu)殘(can)余(yu)氣體分子(zi)發生碰撞電(dian)(dian)離(li)，所產生的離(li)子(zi)電(dian)(dian)流與(yu)殘(can)余(yu)氣體密度(du)即真空度(du)近似(si)成比(bi)例關(guan)系。對于(yu)(yu)不同的(de)真空管(guan)型號（管(guan)型），由于(yu)(yu)其(qi)結(jie)構不同，在同等(deng)觸(chu)頭開距、同等(deng)真空度(du)、同等(deng)電場與磁場的(de)條(tiao)件(jian)下，離子(zi)電流的(de)大小也不相同。通(tong)過(guo)實驗可以標(biao)定出各種(zhong)管型的真(zhen)空度(du)與離(li)子(zi)電流間的對應(ying)關系曲線。當測(ce)知離(li)子(zi)電流后，就(jiu)可以通(tong)過(guo)查詢該(gai)管型的離(li)子(zi)電流一真(zhen)空度(du)曲線獲(huo)得該(gai)管型的真(zhen)空度(du)。

在(zai)(zai)常規磁控放電測試滅(mie)(mie)弧室的真空(kong)度(du)時，為了(le)提高其(qi)測試靈敏度(du)，需(xu)從(cong)斷路器上卸下滅(mie)(mie)弧室，并(bing)置(zhi)于螺線(xian)管(guan)線(xian)管(guan)內(nei)。這樣(yang)一來，滅(mie)(mie)弧室在(zai)(zai)重新裝回(hui)斷路器時需(xu)要(yao)調整機(ji)械參數，工作量很(hen)大(da)并(bing)需(xu)專業人員(yuan)。而使用新型磁控線圈可以從側面包圍滅弧室(shi)，這樣(yang)就不(bu)必拆卸滅弧室(shi)。而采用單片微(wei)

機進(jin)行同(tong)步控制(zhi)與數據采集處(chu)理，提高(gao)了滅弧室真空度的現(xian)場(chang)測試靈敏(min)度。

真空(kong)度真空(kong)開(kai)關(guan)測試(shi)儀  工作原理(li)

真(zhen)空度測試儀框圖如圖1所示。

圖2   放電波形圖

整機(ji)由測(ce)(ce)(ce)量控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)場(chang)高壓產生電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)、磁(ci)(ci)場(chang)線圈電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)、通(tong)訊、打印機(ji)、液(ye)晶顯示(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)等組成。其工(gong)作(zuo)過程為：由測(ce)(ce)(ce)量控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)發出(chu)指令(ling)，由開(kai)(kai)關電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源給(gei)磁(ci)(ci)場(chang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，通(tong)過控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)監控(kong)(kong)，當磁(ci)(ci)場(chang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容上的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓達到(dao)預定(ding)值后(hou)，控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)發出(chu)兩路(lu)(lu)控(kong)(kong)制(zhi)信(xin)號分別(bie)控(kong)(kong)制(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)場(chang)高壓的(de)(de)輸出(chu)和磁(ci)(ci)場(chang)線圈電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)導通(tong)，使滅(mie)弧室處(chu)于(yu)強電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)場(chang)、強磁(ci)(ci)場(chang)的(de)(de)狀(zhuang)態中，滅(mie)弧室開(kai)(kai)始(shi)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，產生離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)I，如圖(tu)2中的(de)(de)曲(qu)線I所示(shi)。該電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)經取樣電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻R和預處(chu)理(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)后(hou)輸入(ru)單片(pian)機(ji)，最(zui)后(hou)經運算(suan)由液(ye)晶顯示(shi)屏顯示(shi)測(ce)(ce)(ce)得的(de)(de)真空度(du)值。