Bai 1 :DOng co m6t chidu kich trj ndi tidp co c6c s6 liQu dinh mrrc: 1500 V ;2000kW, BoOv/ph. Th&
nghi6m khOng tAi mdy nhut 6 trudng hop mdy ph6t kich ttt ddc lAp, vdi tdc dd B00v/ph, c6 bAc ket quA
sau :
E, IVI 0 480 900 1190 1 350 1 450 1 550 1 640 1 730
lr,IA1 0 2so 500 750 1 000 1250 1 500 1 750 2000
Eu : srlc dii6n ddng cAm 0ng trong ddy qudn phdn l?ng; 111 : dong kfch trl.
86 qua hien Wqng phdn Ong phdn ung. Di6n tr6 dAy qudn kich trt ndi tiSp: Rp1= 0,OO5O;di6n tr6 mqch phdn fng (kd cA di6n tr6 dAy qudn b0 vd dAy qu,in cqlc td phU): Rr' = 0,020Q.
DQng co ldm vi6c vdi di6n dp ngudn'la 1500V. Khi dong phdn rlng lu ldn ltldt la 10OOA vd 1500 A,
tinh cho m6i gia tri dong di6n phdn rlng n6u tr6n:
1 . Tdc d6 quay (1didm).
2. Moment hfru ich tr6n truc md, biSt ring tdng tdn hao sdt, tdn hao do ma sdtVd quat gio dugc xem
nhU ti 16 vdi toc d0 quay vii c6 gi6 tri 125 kW 6 t6c dO 800v/ph (1didm).
3. DOng co k6o tAi c6 moment cAn khdng ddi, ddng ti6u thu bdy gio li:l= 125oA, di6n dp U ddt vio ddng co c6 thd thay ddi. Tinh di6n 6p U sao cho tdc d6 ddng cd la 1000v/ph (1didm).
Bai 2 : Ddng co ddng bd 3 pha, 50H2, 1500kW, cosip6p : 1 ,0, dAy quan stato n6i Y, 2300V , 30 cr,lc ,
c6 di6n khdng ddng bd Xou = '1,954/pha.
1. T(nh dong dinh mLlc va t6c dQ quay c0a d0ng cd (1didm)
2. D6ng co dr-tgc cap di6n trl lr.tdi di6n c6 c6ng suat v0 ctng ldn, 2300 V ; SOHz. Tinh moment ctlc d4i d6ng co c6 thd cung cdp cho tii md kh6ng bi mdt ddng b6, dong kfch ttl rdto v5n gi0 gia tri
nhrj khi ddng co k6o tAi dinh mrlc 0 cosrp = 1 (1didm).
3. DQng co Or,tgc cdp di6n ttj mot mdy phdt turbine hoi 3 pha, stato ndi Y, 2300V , 1750 KVA, 50 Hz ,
2 ct!c, vdi dirOn khdng ddng bO Xoo = 2,65 O. Dong kich trl c0a mdy phdt turbine vd dOng cd duqc didu chinh sao cho vecto bidu di6n sr-t ho4t d6ng c0a hd thdng trong trudng hqp ndy (0,5didm). Khdng thay ddi ddng kich trJ c0a cA 2 m|y, nhUng tAi co hoc tr6n truc ddng cd dr;dc tdng ddn. Tinh Moment cLIc dai md ddng co c6 thd cung cdp cho tAi (O,Sdidm).
Coi cAc mAy trong bai la c{c tiJ dn vA kh6ng kd ddn cdc tdn hao c6ng sudt trong cAc mAy.
Bai 3 : DOng cd kh6ng ddng bQ 3 pha, 4 cr,Jc, stato ndi Y, dltgc cung cdp diQn ap U (gid tri di6n 6p dAy) c6 tdn s6 f thay Odi 0uqc (td b0 bidn tdn), n la t6c d0 quay c0a rdto, s6 vdng dAy 1 pha dAy qudn stato ld Wpn = 600 vdng, hd sd ddy qudn koq = 1.0, di6n trd r6to (dd qui ddi vd stato) r'2 = 1.0a. Bd qua di€n tr6 dAy qudn stato, di6n khdng tAn tu stato, tdn hao sdt cdng nhu tdn hao co hgc.
1 . Tinh t6c d6 quay n c0a ddng cd trong didu ki6n kh6ng tai, 6 f = 50Hz vd f = 25H2. Khi U = 400 V ,
f = 50H2, tinh ttl th6ng cuc daioM dudi m6i cttc tr) trong didu ki6n niy (1didm).
2. Chrl_ng minh bidu thrlc tinh Moment di6n trJ c0a ddng co c6 dang i Mo, - Cy.OM.l,, trong d6 Cy ld
hQ sd, l,=thanh phdn dong di6n t6cdung stato (1,= Lcos<p). Tinh h6 so Cr,,l ? Khi U =400V, f = 50H2, tinh l, khi ddng cd k6o tAi co moment cAn 20N.m (1didm).
3. DOng co k6o tai c6 moment cAn kh6ng Odi Oang 20N.m, dong di6n tdc dung lr drldc gifr sao cho kh6ng ddi. Khi d6 OM = coflst, c6 thd tinh Moment di6n td Mdr theo bidu thrlc sau : Mo, - A.(f -
B.n), trong d6 A, B ld cdc h6 sd cdn tinh cho trudng hqp U = 400V , f = 50Hz (1didm)