Phan I (bo 50Hz)

dien ap mang tu thanh pho vao thuong la 110-220V nhung chung ta gia thuyet xau nhat dien ap xuong 90V hoac tang len den 260V.Tu 90-260V la 1 giai dien ap rat rong nen cac bo dien ap thong thuong khong dung dc ma nguoi ta dung on ap giai rong. Bo 50Hz la 1 yeu cau nan 2 ban ky dung 4 diot theo kieu cau. Dau ra cua cau nan ta co 1 chieu o muc B+ (co trung binh 300V dien ap nay dc loc don gian boi 1 tu hoa tri so 200M/400V roi dua sang phan II chap nha

Phan II chap nha

day la phan chinh cua bo nguon bao gom bien ap nguon JR la 1 bien ap xung lam viec o tan so rat cao cho nen thuong dung la loi FERIT. Phan tu thu 2 la cong tac chap nha

TRong so do nay khi cong tac chap nha o trang thai Off thi muc dien ap trong cuon day kich thich la =B+ (300V). Nhung khi ta chap nha vao On thi toan bo dien ap 300V dan xuong dat thanh 0V. Lai nha ra rat nhanh thi dien ap lai ve muc 300V. Qua trinh chap nha cu xay ra lien tuc voi tan so rat cao thi nguoi ta bien doi dien ap 1 chieu B+ thanh cac xung dien ap nhu hinh ve.....

Nhu vay viec chap nha SWITCHING da bien doi 1 chieu B+ thanh xung dien ap tan so cao (co 15-30Hz) tuc la lai bien 1 chieu thanh xoay chieu

Nhu vay cuon day kich thich khi ta chap nha thi co 2 loai dong dien la dong dien 1 chieu muc B+ va cac xung dien ap xoay chieu tan so cao. 1 chieu khong qua loi bien ap (sinh tu truong) nhunbg cac xung dien tan so cao thi cam ung qua loi bien ap sang cuon thu cap . Muon giu dien ap dau ra on dinh ( cuon 1:12V ,cuon 2: 5V,cuon 3: 115V)thi chi can dung bien phap dac biet giu cho dien ap xung xoay chieu cuon kich thich luon luon khong doi bang hang so

Nho vay cac muc dau ra o phu tai luon luon luon bang hang so

Phan III (phu tai)

Dien ap ra cua phu tai co tan so rat cao cho nen chi can nan loc don gian nhu hinh ve ta cung dat duoc 1 chieu ly tuong

II: tao nhip chap nha (SWITCHING)

Van de quan trong nhat trong bo nguon on ap giai rong la tao nhip cho chap nha, viec tao nhip nay yeu cau:

_Tan so cao co 15-30Hz

_Phai tu dong hoa hoan toan . Vi vay nguoi ta thuc hien cac buc thay doi theo so do sau day

1.Dung den cong suat nguon (so nguon) de lam cong tac chap nha

2.Cuon them cuon day cam ung de lay nguon cho bo dao dong chap nha

So do nay khac voi so do tren la cong tac chap nha co khi da dc thay bang so nguon EBC chan C dc noi voi cuon day kich thich de don nhan muc dien ap cao muc B+ , chan E dau dat con chan B la nhip dieu khien Fh nhip nay co tan so rat cao la 15625Hz hoac 15750Hz va len cao la 2x(15625Hz-15750Hz). De tao nhip cao tan nay nguoi ta cuon them cuon day cam ung tren loi bien ap xung( bien ap nguon); khi co cuon cam ung thi theo dinh luat cam ung dien tu cua Cenxo moi khi o cuon day kich thich co dot bien tang giam dien ap do ta dong mo cong tac chap nha thi tren cuon day cam ung se xuat hien suat dien dong cam ung co chieu nguoc lai so voi su tang giam tren cuon day kich thich . Nho vay tren cuon day cam ung khi chap nha hoat dong xuat hien dien ap nguon . Nguoi ta dung Diot nan nguon nay ra de nuoi bo tao dao dong Fh cua chap nha. Dau ra cau bo nay dat vao cuc B cua con den cong suat nguon dieu khien chap nha

Trong cac may moc hien dai ngay nay uu nhuoc diem cua nguon rai rong

1)Uu diem:_giai on ap rat rong

_Do khong dung bien ap cho nen giam dc kich thuoc va trong luong bo nguon nen giam dc kich thuoc va trong luong cua thiet bi dien tu

_Bo nguon nay con co ten la bo nguon cach li giua phu tai voi nguon vao

_Nho co bien ap nguon loi FERIT ma cach li giua phu tai ben thu cap cua nguon va o ben trai so do do vay neu chap nguon, chay nguon thi khong bao gio anh huong den phu tai . Nho vay thiet bi dien tu dc bao ve rat an toan

Nhuoc diem:_Do bo nguon dung tan so tuong doi cao de chap chap nha cho nen phat sinh can nhieu cao tan anh huong den hoat dong cua cac mach dien tu khac trong thiet bi

_trong bien ap o cuon day kich thich cung 1 luc co ca 2 loai dien ap la dien ap 1 chieu va xoay chieu do vay trong che tao bien ap nay nguoi ta phai tao khe tu ho de chong tieu hao nang luong nguon bang cach lot vao day 1 lop giay mong cach tu