4.5 §Æc ®iÓm ®iÒu khiÓn ®iÒu ¸p ba pha Nguyªn lÝ ®iÒu khiÓn §iÒu khiÓn b»ng c¸ch ®ªmh xung §iÒu khiÓn b»ng chïm xung I. Nguyªn lÝ ®iÒu khiÓn ®iÒu ¸p ba pha §iÒu khiÓn ®iÒu ¸p ba pha cã thÓ coi nh chØnh l u cÇu ba pha T 2 T 3 T 5 T 1 T 4 T 6 a) T 5 T 2 T 1 T 6 T 4 c) T 1 T 2 T 4 T 3 T 5 T 6 b) Ba c¸ch cÊp xung ®iÒu khiÓn • CÊp xung ®«ng thêi cho c¸c van ë nhãm NA vµ nhãm NKvÝ dô nh h×nh vÏ: • Cã thÓ cã ba c¸ch cÊp xung ®iÒu khiÓn T 1 T 2 T 3 T 5 T 4 T 6 A 1 B 1 C 1 A B C Z A Z B Z C 0 0 T 2 T 3 T 5 T 1 T 4 T 6 A 1 B 1 C 1 A B C Z A Z B Z C T 2 T 3 T 5 T 4 T 6 A 1 B 1 C 1 A B C 0 Z A Z B Z C T 1 T 1 T 2 T 3 T 5 T 4 T 6 A 1 B 1 A B C Z A Z B Z C 0 X C X § T 1 T 4 ,T 6 T 2 T 3 ,T 5 T 3 T 6 ,T 4 T 4 T 5 ,T 1 T 5 T 2 ,T 4 T 6 T 1 ,T 3 X C X § T 1 T 4 T 2 T 3 T 3 T 6 T 4 T 5 T 5 T 2 T 6 T 1 X C X § T 1 T 4 T 2 T 3 T 3 T 6 T 4 T 5 T 5 T 2 T 6 T 1 • §iÒu khiÓn b»ng biÕn ¸p xung hai cuén d©y H×nh 3.33 §Öm xung b»ng biÕn ¸p. M§K T 6 tíi T 5 T 6 T 1 T 4 M§K T 1 M§K T 4 • §Öm xung tr íc tÇng khuÕch ®¹i +15V M§KT 1 M§KT 6 H tíi T 4 T 1 H×nh 3.34 §Öm xung tr íc tÇng khuÕch ®¹i • §iÒu khiÓn b»ng xung ®¬n A B C α t t t t t t π/2 π X T1 X T2 X T3 X T4 X T5 X T6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 X 3 X 23 X 2 X 52 X 1 X 61 X 14 X 5 X 6 X 36 X 45 X 3 X 4 X 14 T 1 T 2 T 3 T 4 T 5 T 6 • M¹ch ®iÒu khiÓn V 6 A 5 A 4 +12V T 6 +15V -12V UC U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 5 T 5 UB U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 3 T 3 V 4 A 5 A 4 +12V T 4 +15V -12V UA U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 1 T 1 D 4 V 2 A 5 A 4 +12V T 2 +15V -12V H1 H2 H3 H4 H5 H6 -12V Udk §iÒu khiÓn ®iÒu ¸p ba pha khi van lµ triac U A U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + DA R 7 D 4 D 5 X U A R 5 Tr 2 Tr 3 U B U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + DA R 7 D 4 D 5 X U B R 5 Tr 2 Tr 3 U C U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + DA R 7 D 4 D 5 X U C R 5 Tr 2 Tr 3 -12V -12V -12V +12V +12V +12V +15V HA HB HC -12V TA TB TC • §iÒu khiÓn b»ng chïm xung A B C α H×nh 3.39 §iÒu khiÓn ba pha b»ng chïm xung t t t t t t t X 1 X 2 X 3 X 4 X 5 X 6 + A6 D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 - AND T 5 T 6 T 3 T 4 +15V T 2 D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 AND +15V +15V D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 AND +15V ∼ ∼ ∼ . C α H×nh 3. 39 §iÒu khiÓn ba pha b»ng chïm xung t t t t t t t X 1 X 2 X 3 X 4 X 5 X 6 + A6 D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 - AND T 5 T 6 T 3 T 4 +15V T 2 D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 AND +15V +15V D 4 Uv U ®f 1 U R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D AND ®f 2 R 2 A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + C 1 R 5 A 3 - + D D 4 AND +15V ∼ ∼ ∼ . khiÓn V 6 A 5 A 4 +12V T 6 +15V -12V UC U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 5 T 5 UB U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 3 T 3 V 4 A 5 A 4 +12V T 4 +15V -12V UA U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 1 T 1 D 4 V 2 A 5 A 4 +12V T 2 +15V -12V H1 H2 H3 H4 H5 H6 -12V Udk §iÒu. C α t t t t t t π/2 π X T1 X T2 X T3 X T4 X T5 X T6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 X 3 X 23 X 2 X 52 X 1 X 61 X 14 X 5 X 6 X 36 X 45 X 3 X 4 X 14 T 1 T 2 T 3 T 4 T 5 T 6 • M¹ch ®iÒu khiÓn V 6 A 5 A 4 +12V T 6 +15V -12V UC U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 5 T 5 UB U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 3 T 3 V 4 A 5 A 4 +12V T 4 +15V -12V UA U ®f1 U ®f2 D 1 D 2 VR 1 R 1 R 2 A A 1 + - B R 3 R 4 D 3 Tr 1 C A 2 - + R 4 U ®k R 5 R 6 A 3 - + D V 1 T 1 D 4 V 2 A 5 A 4 +12V T 2 +15V -12V H1 H2 H3 H4 H5 H6 -12V Udk §iÒu