NGHIEN CIIU-TRAO DOI ^ HIEN THL/C DAC TINH DIEU CHINH TY LE CUA VAN SERVO BANG TO HOP VAN TIET LUU THUY LL/C UfNG DUNG DIEU KHIEN KY THUAT SO PROPORTIONAL CHARACTERISTIC REALIZATION OF VALVE SERVO BY HYDRAULIC ORIFICES COMBINATION USING DIGITAL CONTROL TS Hoang Sinh Trirding Trudng Dai hgc Bach Khoa Ha Ndi TOM T A T Bdi bdo trinh bdy khd ndng hien thuc dac tinh dieu khien ty le (analog) cua cdc van servo thuy luc bdng cdc td hap van tiet luu khdng dieu chinh kit hap phdn mem dieu khien bo khd trinh Vdi khd ndng loc xung, gidm chdn tdt, viec tao bd bien ddi D/A [3] dtta tren nguyen ly thuy luc Id hodn todn hien thiic vd cd the dap dng yeu cdu dieu khien, dac biet vdi cdc he thdng qudn tinh khdng qud l&n Vai sit kel hgp ndy cho phep tao duac mot he thdng dieu khien dien thiiy lire thay the van servo vai dac tinh dieu khien tuong tu nhung vai tinh tieu chudn cao, tin cdy cao vd vai gidm chi phi ddng ke Hieu qua se duac hien thuc bdng su don gidn cua he thdng gidm thieu phu thudc ky thudt vdo nhd cung cdp thiet bi, ndng cao dd on dinh van hdnh TCr khoa: Ty le; Thiiy luc; Van servo ABSTRACT This paper presents the realization ability of proportional features (analog) of the hydraulic servo valve to the combination unadjusted orifices and a software programmable to filter pulses, better damping and converters controller With the abili^ D/A[3J based on hydraulic principles, it sfully realized and can meet the control requirements, especialiy with the not too large inertial systems This combination allows to replace the hydraulic servo valve in a power system control having similar controls characteristics but with high standards, high reliability at^ to reduce costs significantly The effect will be realized by the simplicity similar controls to minimize tk dependence on suppliers of technical equipment, enhance operational stability similar control Keywords: Proportion; Hydraulic; Van servo: Servo valves TAP CHi CO KHI VIET NAM, S6 nam 2014 www.cokhivietnam.vn NGHIEN cuu-TRAODOI l.DATVANDE Van servo thuy luc la nhung phSn tu quan khdng th8 thidu cac he thdng didu khidn tu ddng dien thiiy luc cd yeu cSu chinh xac va tu ddng hda cao Tuy nhien, su dung chinh mem, giam thieu anh hudng luc quan tinh he thong Qua trinh co cau chap hanh chuyen ddng vdi tdc dn dinh, tinh ty le ciia van it cd anh hudng den chat lugng dieu khien cac loai van ludn sinh mot sd vSn dk bSt cap [1] Tinh tieu chuan khdng cao: Do viec hieu i chinh didm ciia phSn tu ddi hdi thidt bi va ky thuat phiic tap va thudng chi thuc hien bdi nha cung cap nen rdt phu thudc thay thd cac phkn hi Tinh on dinh khdng cao: Viec hieu chinh diem ciia cac phan tu thudng xuyen xay phu thudc kha nhieu vao dieu kien mdi trudng lam viec (nhiet mdi trudng, nhiem ban ciia dau v.v) va phan khuech dai analog thudng kem on dinh Gia cao, yeu cau ky thuat bao duong cao, chi phi van hanh cao Nhiing bat cap neu tten cd phan nguyen nhan ca ban nguyen ly cau tao cua van servo, bd bien ddi dien thuy lure thudng cd diem khdng dn dinh, kem theo dd khac biet Idn ve tdc truyen tin hieu ciia cudn dieu khien vdi tdc anh sang (hinh 1) va he ca thuy luc ciia truydn -ban chan vdi van thuy luc cd tdc am vdi quan tinh Idn nen dn dinh cua he thdng bi han che Trong da sd trudng hgp thuc te su cd thudng gap vdi van servo dd la anh hudng cua ma sat van ma nguyen nhan chu ydu chit lugng dau nhiem ban, hoac dac tinh hai vdi phun thay ddi do nhdt dau bien ddi bdi nhiet Thuc td cho th4y, tinh ty le cua van servo hieu qua chii ydu dd cho phep qua trinh khdi ddng va qua hinh dung cua ca ciu chip hanh dugc dieu B Hinh 1: Van servo 4WS2EM~6-2X/ vd sa nguyen ly cdu tra khdng De tranh nhiing bat cap neu h-en ma vh\ tao dugc qua trinh dieu khien mem cho cac ca ciu chap hanh thuy luc, dac biet ddi vdi cac he thdng dieu khien chu ydu, tac gia de xuat mot md hinh td hgp van logic thuy luc tieu chuin kdt hgp mot phan mem dieu khien thich hgp vdi bd kha trinh PLC tieu chuan cdng nghiep thay the van servo