1、1999 M 4 v ( 1 S ) Apr. 1999 12 2 Journalof YantaiUniversity (Natural Science and Engineering) Vol.12 No.2/ PWM 控制原理在自动控制中的应用X王桂枝(烟台大学物理系, 烟台 264005)K1PWM控制原理被广泛用于自动控制中,我们研制的“BF? 07自动控制发酵罐”就是利用PWM控制原理实现了对温度、搅拌速度、酸度、溶解氧4个参数的调控.本文给出PWM 控制原理及利用PWM控制原理实现对温度和搅拌速度的调控.1oMPWM z 1 b v ms |TP271L C 1 e V Z T
2、,PWM e Z T e r T z B .PWM(pulsewidth modulator) e Z T l ? 4 e , ? e H W ,V7 z % e e H W W . ,PWM e Z T $ W 1 e “ d . o BF 07 1 e ? 7 p N e Z T L C (T) , (RPM)a (pH)a (DO) e . N ! ! X 4 ? v “ 1 a v 3 “ 2 a v “ S s S T .m11 e?7“d1. . ;2. ;3.pH ;4. , A5 ; 5. . ; 6. ;7.F ;8. H D ;9.1 e N ;10.? 7 ;11. =
3、.11 e?7“d1 ? 7 ( m 1) 7 8 s F , j c ,8 7L, / V , F , Q .1 e N 4 : a a # e , B A U ,s H A U ! # L , H : c u 4 L , 4F w L .2PWM e # X l :1998- 11- 09PWM e : $ e 5 ! B , N L 1 1 , T M , 3 ,1 B “ , z L 1 “ ,N ( ? 7 1 , 7 1 ( ? q , q z H W T . v , z z , q T H W , P L ! h l ; l H , z M N , q T H W , ! L M
4、 , r 1 e “ .PWM e 1 o ( m 2). : A 1 o ? 3 3,4 a A 2,A 3 b v ,A 4 1 a A 5 ./ H w z H $V = V s- V t W 1 “ T , Vs V ! ,V t L .A 1 o ? 3 1 T Q R13,C1, C1 o , V 0 = R11VhR11 + R12. Vh A1m2PWM . o T C1 b H W , b H W M , 1 p b H W V p T. b Vc T , Vc = A + Be - tR13C1. A,B “ ,R13 C1 b E . t = 0 H ,Vc = R11V
5、hR11 + R12; t = H ,Vc = - V h,5 A = - V h, B = R12 + 2R11R11 + R12V h,V c = - Vh + R12 + 2R11R11 + R12V he - tR13C1. (1) t = T2 H , b 8 ,Vc = - R11VhR11 + R12 (1) T - R11V hR11 + R12 = - Vh +R12 + 2R11R11 + R12 Vhe- T2R13C1,5 T = 2R13C1ln(1+ 2R11R12 ). T R13,C1,R11,R12 1 . o Vc o m 3(a).A 2,A 3 b v
6、, s F :Vc,V s,V b,Vc o ,V s ! ,V b , $ e “ d 1 , v Vb 9 v , S z 9 v .b v V8 9 o , V X $ Vs Vb ( m 3(b) U , o M (Vs + Vb) .c144c 烟台大学学报(自然科学与工程版) 第12卷m3PWM omV8 = K(V b + V s + Vc).K b v , R22,R23, R24, R25,R33,R31 1 ,A 4 1 ,V 8 Vt M 1 ,A 4 V14, o ( m 3(c),(d), H z , o / , 9 V s , V t M 1 3 z 9 . m 3
7、(b) M HT =V 0 + KV b + K Vs - Vt2V0, H = T21+ K(Vb + Vs) - VtV0. K = 1 H ,H = T2(1+ VbV0+ $VV0). (2) $V = V s- Vt, (2) T A z H $V L 1 1 “ ,T,V0,Vb q 1 ,7 e 1 .V s ! v , $V v , o M v ,H z . Vb ! a H V , K v T.3PWM e em4 e“d e “ d m 4 U . . BTSI “ . 5,M | f ( 2 10mV/ ), A U A U ,i O : c N # PWM .PWM e
8、 , 3 , z L 1 “ ,SSR1 % ? , ( 7 1 , = ; , F ? , T V L ,SSR1 e q i i F F H W , v H , PWM e , P F F H W , L y ! ,h e H W ; l H ,F F , 6 , . e “ d “ d 6, , A V C , 1 ? e , 9 F F = T e ZT V l , Q . , $ e ! 1 H W , 7 e . z % B a PWM e Z T K v .m 4 DCM SSR2 e Y ,SSR2 % ? , e Y H D ;DCM e v , F , P e + .B e
9、 : 1 L ! , F , “ P v , + Y T M v H ( ? 1c145c第2期 王桂枝:PWM 控制原理在自动控制中的应用? , 2 Z Z ) | 1 1 M v , P e S / . DCM ,F H W V 1 , 1 ? T H , V 4 - Y , ? T H , V Y . L l ,DCM F d L , T M / e S / . P $ e V v v h l , e V L .m5 e o e L = o m 5 U . L = q : R11= R12= R13= 18k8,C1 = 0.1LF, 5 T = 4ms.m 5(a) o V c o ,
10、 - Vp = 4V,Z o A 1 o , - V p = 9.5V, Ec = 10V.m 5(b) o V8 o , V c o $ V b Vs o , L V s, ! , . m 5(c) o (b) A 4 M 1 , V14 o , o V8 o . m 5(s),(t),(r) o z h , l v , o 1 / 7 M . ! V s l v M H V14 V 8 o M . - w T (2), Vs 9 v , $V 9 v ,H 9 9 v . e S 10j 60 , ? 1 . 0.1 .4PWM e em6 e“d e “ d m 6 U . ? H 1
11、, P ( a i a h a h“ , ) ( . . SZMB 4 H T , .F/c146c 烟台大学学报(自然科学与工程版) 第12卷V M .PWM e , e L ,Q , b 4 e q i i 5 ? 7 ! , 5 0 M 1 ,PWM e 5 , P T , 5 E , P F M ,V 7 M r “ . 5 T , ? l , 5 ( l . r q , e ? z , ? M v S = . 1 a , L = : R11 = R12= 12k8, R13= 2k8, C1 = 0.1LF, T = 0.44ms, f = 2.27kHz, f H , 2 v ,f
12、 H , , . L = 1 p , V S 100j 1000r/min.9 , 1 e ? 7 e “ d PWM e , e , e r T z a Z L . ID1 , m , u . W u # F ? ,n : F , ,S I . B S 3 p “ . : ,1995.1972 f , ; , I . L s ? 3 Y . n : F , ,S I . B S 3 p “ . : ,1995.1793 B . 0 / $ . = . : ,1988.557j 5594 Millman J. Microelectronics DigitalandAnalog Circuits
13、 andSystems. New York: Mc Graw-HillBookCompany, 1979.6255 f . L 1 e . : + S / ,1992.2536 7 . ! 9 m . f C I r . : S 9 ,1989.92j 97Application of PWM Controling Principle in Automatic ControlWangGuizhi(Departement of Physics, Yantai University, Yantai 264005)Abstract PWM controlingprincipleis used ext
14、ensively inautomaticcontrolcircuits. Thispaper showsd PWM controling principleand applications of theprinciplein the o BF 07ptypeantomaticcontrolfermatationpot. Usingtheprinciplebothtemperatureandagitationspeed controls areachievedKey words pulsewidth modulation, pulsewiath, comparator, amplifier( 3 I k )c147c第2期 王桂枝:PWM 控制原理在自动控制中的应用
