數(shu)控(kong)系(xi)(xi)(xi)統的設(she)計要求系(xi)(xi)(xi)統動(dong)作準確無誤，每個(ge)控(kong)制動(dong)作都(dou)要達到(dao)它想(xiang)要的目的。造成數(shu)控(kong)系(xi)(xi)(xi)統工作不正常的原因除了系(xi)(xi)(xi)統故障外大部分是受到(dao)外界電磁干擾。
一、干(gan)擾產生的(de)(de)原因:電火花機床(chuang)利(li)用高(gao)頻放(fang)電對工(gong)件腐蝕加(jia)工(gong)，高(gao)頻對智能糾錯(cuo)控制(zhi)器產生干(gan)擾。干(gan)擾一般是指(zhi)那些與(yu)信號無關(guan)的(de)(de)，在信號輸入、傳輸和(he)輸出過程中出現的(de)(de)一些不確定的(de)(de)有害(hai)的(de)(de)電氣瞬(shun)變現象。這些瞬(shun)變現象會使數(shu)控系(xi)統中的(de)(de)數(shu)據在傳輸過程中發生變化，增大(da)誤差，使局部裝(zhuang)置或整個系(xi)統出現異常情況，引起故障。干(gan)擾源的(de)(de)產生主要(yao)有以下幾種情況:
①電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)干(gan)擾:由于電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)覆蓋范圍廣，存(cun)在(zai)多種設備共(gong)享一個電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)，尤其是電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)內部的變化，數(shu)控車床廠家電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)開關操作、雷擊浪涌、大型(xing)電(dian)(dian)(dian)(dian)(dian)力設備起(qi)停、交直流傳動(dong)裝(zhuang)置引(yin)起(qi)的諧波(bo)、電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)短路暫態(tai)沖擊等，都通過輸(shu)電(dian)(dian)(dian)(dian)(dian)線路傳到電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)原邊，使(shi)電(dian)(dian)(dian)(dian)(dian)壓(ya)暫變，導致電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)電(dian)(dian)(dian)(dian)(dian)壓(ya)波(bo)動(dong)。此外(wai)，電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)線在(zai)傳輸(shu)過程也(ye)會產生噪聲以及快速瞬變的脈(mo)沖串，污染電(dian)(dian)(dian)(dian)(dian)網(wang)(wang)。
②輻射干(gan)擾(rao):電(dian)(dian)(dian)磁(ci)或電(dian)(dian)(dian)場(chang)在自然界中無處(chu)不在。工作(zuo)中的電(dian)(dian)(dian)火花穿孔(kong)機除了受到電(dian)(dian)(dian)場(chang)的作(zuo)用外還受到了磁(ci)場(chang)的作(zuo)用。電(dian)(dian)(dian)火花穿孔(kong)機在運(yun)行過(guo)程中，由(you)于工作(zuo)環境的惡(e)劣性，不可避免的會受到電(dian)(dian)(dian)磁(ci)干(gan)擾(rao)
③數字信(xin)號(hao)(hao)(hao)(hao)和(he)模(mo)(mo)擬信(xin)號(hao)(hao)(hao)(hao)間(jian)的(de)(de)干擾:電(dian)(dian)火花穿孔機在工作過(guo)程中，由(you)于(yu)整套設(she)備涉及(ji)到的(de)(de)器件(jian)較多，各(ge)種低(di)壓直流電(dian)(dian)信(xin)號(hao)(hao)(hao)(hao)。數控(kong)車床(chuang)廠家用來(lai)傳遞信(xin)號(hao)(hao)(hao)(hao)的(de)(de)電(dian)(dian)纜，在走(zou)線(xian)(xian)過(guo)程中，有(you)時會(hui)由(you)于(yu)模(mo)(mo)擬信(xin)號(hao)(hao)(hao)(hao)輸出設(she)備或由(you)伺(si)服驅動器或變頻器產生的(de)(de)干擾引(yin)起誤動作發生，影響(xiang)設(she)備的(de)(de)正常(chang)工作;用來(lai)傳遞I/O輸入(ru)/輸出信(xin)號(hao)(hao)(hao)(hao)的(de)(de)頻率受到時鐘頻率和(he)諧波(bo)干擾，加上線(xian)(xian)路走(zou)線(xian)(xian)不當，使數字信(xin)號(hao)(hao)(hao)(hao)線(xian)(xian)和(he)模(mo)(mo)擬信(xin)號(hao)(hao)(hao)(hao)線(xian)(xian)不可避免的(de)(de)會(hui)受到外來(lai)干擾信(xin)號(hao)(hao)(hao)(hao)的(de)(de)干擾，各(ge)種信(xin)號(hao)(hao)(hao)(hao)線(xian)(xian)相(xiang)互(hu)之間(jian)也會(hui)通過(guo)線(xian)(xian)間(jian)耦合等產生干擾。