Note: Torque is prop. to current Stationary voltage is prop. to speed

Transcription

1 DC Mach Cotrol

2 Mathmatcal modl. Armatr ad orq f m m a m m r a a a a a dt d ψ ψ ψ ω Not: orq prop. to crrt Statoary voltag prop. to pd

3 Mathmatcal modl. Fld magtato f f f f d f dt a f ψ m m f f m fλ

4 h torq orc lmtd Oft pd dpdt,.g. fld wag orq, Flx Voltag, Powr otor crrt Spd

5 Fld wag a ω ψ a,max r ω m r, om ψ m, om ψ m ψm, om f ωr, ψm, om ωr om ω < ω r f ω > ω r r, om r, om ψ m f f ωom ωmax

6 orq J dt J dt d J J dt d l l l l ω ω ω

7 Cacad cotrol for poto cotrol Motor Θ - Poto cotrol ω Spd orq cotrol cotrol - - J ω Θ

8 orq cotrol crrt cotrol Motor Motor - orq cotrol Ψ I - Crrt cotrol ψ m a

9 oop oad orq l l w ω w Stp f Act PI Cotrollr Ot tc. 't ordr orq Sorc Modl Spd fltr J. Irta f. Udc /Pm Crrt rfrc f Act Sampld Crrt Cotrollr a,b dc a,b va vb m pha lvl modlator Udc va a b a,b vb 4Q lvl vrtr a l a wr orq Spd tat 4Q, Hytr Crrt Cotrollr oad torq DC

10 So far Modlato... Udc /Pm Crrt rfrc f Act Sampld Crrt Cotrollr a,b dc a,b va vb m pha lvl modlator Udc va a b a,b vb 4Q lvl vrtr a l a wr orq Spd tat 4Q, Hytr Crrt Cotrollr oad torq DC... or, how to covrt a voltag rfrc to a pl wth modlatd voltag

11 Nxt tp Crrt cotrol... Udc /Pm Crrt rfrc f Act Sampld Crrt Cotrollr a,b dc a,b va vb m pha lvl modlator Udc va a b a,b vb 4Q lvl vrtr a l a wr orq Spd tat 4Q, Hytr Crrt Cotrollr oad torq DC... or, how to covrt a crrt rfrc to voltag rfrc, or mayb a PWM pattr drctly...

12 Problm ad ma to cotrol crrt Problm: Crrt dyamc ar xtrmly fat Ma Aalog cotrollr Fat, bt pro to drft Dffclt to mplmt o lar cotrol law Dgtal cotrollr Not a fat, bt xact Eay to mplmt o lar cotrol law

13 Fat: Comptr pd a Marmt of crrt rfrc ad crrt - 3 M odlato wth w voltag rfrc t Calclato of voltag rfrc Dlvry of w voltag rfrc Slow: b Marmt of crrt rfrc ad crrt - 3 M odlato wth w voltag rfrc t Calclato of voltag rfrc Dlvry of w voltag rfrc Coto: c t Marmt of crrt D trm ato of w w tch tat Sttg of w wtch tat

14 Grc oad d dt

15 Crrt cotrollr wth fat comptr -I,,, dt dt dt d dt dt,,, 0 d c b a th voltag rfrcdd voltag dad bat, th crrt rror lmatd o ampl h crrt chag lar ot alway tr h bac mf do ot chag o amplgot alway tr r for dad bat

16 Crrt Cotrollr wth a fat comptr II { forward Fd Itgral oportoal 0 Pr

17 Compato for a low comptr - th Smth prdctor : I U a dmmy ytm that mlat th crrt rpo to voltag rfrc. t th dmmy ytm b prly tv-idctv,.. NO EMF! mth mth mth d mth dt

18 h Smth Prdctor : II h SP wll hav th am dyamc a th ral ytm, bt ot th am tatc. d dt h l th: mth, tatc mth ral, mth d dt Am tatoarty -> omator of th crrt drvatv 0 ral tatc A voltag chag gv th am drvatv both ca. ral

19 h Smth Prdctor : III Calclat th crrt of th xt amplg tat a th m of: h crrt mard at th lat amplg tat h chag of th crrt bad o th voltag rfrc at th lat amplg tat...: ˆ mth mth mth mth mth mth mth mth mth mth mth mth - -

20 h Smth Prdctor : IV mth mth d_mth /z /z tc/ -K- /z

21 Crrt Cotrol wth a low comptr : V ˆ ˆ ˆ 0

22 Drct Crrt Cotrol Swtch tat oly a fcto of crrt rror No trmdat crrt cotrol or modlato

23 -Qadrat Drct Crrt Cotrollr lay E-crct Crrt rfrc 00 Udc Udc v 4Q lvl vrtr < < < < < > > < ; 0 ; ; f f f

24 Stat a 4QC V d 3,- V V a 4,- 0

25 -Qadrat Drct Crrt Cotrollr lay E-crct Crrt rfrc 00 Udc Udc v 4Q lvl vrtr < < < < < > > < ;,, ;, ;, f or f f

26 4-Qadrat Drct Crrt Cotrollr Mor trcy: 4 tat [-,-], [,], [,-] & [-,], bt Oly 3 otpt voltag -Udc, 0, Udc O olto: [a, b] [, -] cra [,] or [-, -] rt [-,] dcra