CA2079251A1 - Circuit arrangement - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A circuit arrangement for the control of the braking of a four quadrant drive which consists of two rotating electric machines mounted onto a common shaft.
The drive contains an externally excited c.c. driving motor and an externally excited d.c. braking generator which is connected to it mechanically, directly or through a gear ratio transmission. The generator armature is created with a braking resistance which has small impedance as a closed circuit and into the armature circuit of the driving motor.
An armature current sensing stage is inserted which observes the armature current. The current changes proportionally with the torque of the motor. The current sensing stage is connected to the comparator stage and to the output of the latter the Rgg excitation coil of the generator is connected which, with the comparator stage, the current sensing stage and through the polarity changing switch, together with the Rgm excitation coil of the driving motor is connected to the control voltage.

Description

2~ 5~1.

CIRCUI~ AF;:R~NGEI'IENT fOR THE CI~NTF~L OF ~ FO~ ADF~l~NT DkIVE
~ONTATN~NG TWO ELECTRIC R~T-4TING ItACHIl~lES WHIC~3 ~RE ~SOUI~T0 ONTD
A COMt~ SHf~F~

~nnouced by:
Frank CSf~SZ~ electro--mechanical technic~ aln 60Z.
16 ~etbury Cr~Dun Mi~ls Ont.
Canada B~LI~T ~stv~n mechanical enqineer 26'X.
Budapest, XV~ Metro u. ~3.
~N~TI-~UM~N 5~ndor mechanical engin~r 14X
~udæpest~ rtor.he~yi ~t 20~F

Data of announce~ent: ~7.0~19~1.

The ob~ect ~f th~ i~ven~on i5 a circuit arrangement which ~s suita~le for th~ contr~l of ~ four ~u2drant drive which ~n~ist~
of t~o electriC rDta~ng machi~es mounted onto a com~on sha~t, which drive consi5ts ~f a d^e. ~riving ~ot~r with external excitation and a br~kin9 ~ener~tor with a statur havin~ ~alie~
pDles excited by dire~t current, which qenerator i5 coupl~d fr!echanical ly ~itter dir-ctly or throtl~h a ~e~r ratis~ tra~sn~iYSLOn to the drivin~ motor. Th~ eircuit arl-angem~nt of the inventior~ is ad~ant~9eou5~y appllrab~e in al 1 su~h cas--g~. where . there. is ~eed ~or a four quadrant drive ~ the siyn ~t th~ ioading ~c~rque ~nd ~hat of angular Yelocity of fhe ~rivirs~ m4tor ch~ges treql~ntlY and at th~ same tim~ ~uch a dr~ve has to ~e r~?ali which h~ ow inertia~ is stabl~, an~ is k.e~pir~g s~ctic~nw~s~
its angul~r velocity con~ta~t~
By th~ developm~rtt and the ~requ~n~ ~ of ~t~e se~icorl~uc or t6i~hnique, the ~o~lr--~adrant d.~ motor ~irivcs c,r~ ~ettin~ ~3ain a ~ide-spread application., Within this" 9en~raly three types ot th~ bFaking of the exterr~ally ~xcit~d d.c. m~tors ~re distin~uish~?d: the recup~rative~ th~ resist~nce hrakin~ and ~he p 1 u~Qinq .

2~ 5.'l.
~ he c~se of the recuDeratlve brakina oa~urs~ ~hen the s~eed of the fr~ the d.e. net~ork fed ~otor will become ~araer than i~s no }o~ s~Qd by the application of an external tDrque! thus t ts iQ~uced v~lt2se will beeome laroer th~n th~ voltaoe of the ~.~plied nQtwork. ~he directioh Df the motor current will reverse an~ will turn into ~ aenerator w~rking parallel to the network and will deliver ener~y to the network With ~he chanae in the c~rr~nt ~ir~e~ion the 5~9n of the torque will chan~e as well and the motor will ~ert a ~raking e~fect. Though the recu~era~ive br~kinw ~5 eco~omic~ b~caus~ ap~rt ~rom the motor ~Q~ses the brakin~ ener~y i5 re~ai~ed! b~t itc di5~dvantaq~ having a eonstant te~min~l volta~e i~ ~h~t ~ith thi~ ~ode of brahir~ it i5 not pQs~ible tQ C4~ to a stop at ~ nd brak~n~ is ~en only ~t lar~er spee~5 th~n the n~ load 5~eed p25ei~1e in the ca~e ~f ordinary ~pplieations~
~ pplyin~ th~ re~ist~ne~ brakinq the armature cir~uit o~ the m~tor i9 5w~tched o~ from ~hr netw~rk~ w ~le the excit~ticn coil r~main~ henc~Qrward c~nnected to th~ network. Th~ r~ist~nce braking ran b~ r~garded a5 ~ener~or ~o~ of operation as well as the mo~r n~w a5 a ~ner~tor is rel~sin~ ener~y to the braking res~s~ance~ ~ut th~ enQrgy aecumul~t~d in the rotati~ ma~5 cannot iR ~his ea~ be re~overed. i~ wi}l bQ ~u~ 1Y transformed iRt~ h~at in the heat c~rc~lt~ he induced vo~tage i~ ke~p~ng it~ direction ~cauge the direction of th~ rotation and the polarity of thQ fluK is unch anged~ and ~he Yoltage o~ the network is switehed o~ th~ directi~n of th~ current in ~he mo~or wi11 ch3n~e~ Ag a con~uence the tor~ue will chanue its si~n a5 well and th~ wi~l 5t~rt to ~x~rt a br~kin~ effee~ w~
w~nt to ~rake with the re5lstanc~ ~rakin~ ne~r to ~t~nd. ~
th~n mnre r~si~tanCe 5t~0e~ h~ve to be appl ~ ~d . 1t can be regarded a~ a . ad~nt~ge ~5 well~ that durin~ ~r~k~n~
s-imult~neoUclY with the spe~d the indu~ed volta~e d~creases a~
, ~hus in order tQ d~elo~ ~ su~ici~ntly l~rg~ hrakin~
~orque the resist~c~5 connect~d to th~ ~indiny ~f th~ rot~r hav~
t~ be gr~du~lly switched of~. Furt~er ~. ~nt2ge of the sys~em~
that ~es2~se of th- int~rnal r~i~t~nce ~f the armature th~ ic no ~05aib~ lity ~o brak.~ ~ntil stands~il} ic re~ched~ on the oth~e `

2~ t~

hand th~ develoD~ent of tor~e 1~ subject to th~ rot~ti~n of the motor. Therefore 9e~r~1 1Y W~ are braking with reStistance bra~in~ in gener~l only up tc low 5peed. from then onwards sto~ng of the e~uipment i~ en5ured by the ~pplicati~n of mechanical br~ke. whioh i~ anyway hecess~ry as a fastening brake.
Plugging occuo~. when t~e ~tar ~rma~ure an~ the excit~tion coil is connected ~ccordlng one rotatlon direction~ ~ut the m~tor i5 driven by t~ external ~o~d tor~ue in th~ oppo~ite dire~tion. ~v pluggin~ havin~ Qe torq~ he br~kin~ ef~ect can ~e extended even to the ~tand5till ~ositi~n. but ~t the ~oment when the ~ot~r c~me~ ~o ~ Ft~p th~ motar has tQ be ~witche~ of~ otherwise it would ctar~ to rot~t~ in the e~h~r dir_ction. Therefore this mod~
~f brakin~ i5 applied ~aanlr et sn ca~ed dir~cti~n m~inlr at ~o ca~led direeti~n chanein~ drives~ ~here the ~rakinG and acceler~tl~n into th~ o ~o~itE dir~ct~n is ~erformed within onu process- ~he brak~n~ er~y -5 cDnverted here a~ ~ell into heat.
~t eomD~re~ with the rY5l~t~nce braking be~ause of the larger v~lt~ h-vin~ th~ 5a~e current ~Ul~ipl~ enorgy l~ss~s will ~c~r. ~rther deficienry of the 501~tion~ in larg~ are.~c where driYes are ap~l~d thi~7 kind of ~riv~. b_easse af its lnhYrent pr~pertieS i5 not ~p~lic~ble- ~imilary the~ WQl 1 known and ~l~gc~ca~ Pxam~e ~f a drive cY~tem! ~hich i5 cQmpo~ed ~f ms~re machinQS i5 the W rd-Le~nard 5y5tem4 which belon~s to the fow ~uadran~ ~y~te~s tG~- Thol~ch thi5 sy~em can be asppli~d ~dvantag~usly evg. in rollin8 n~lls~ ~or driving in ~he m~chining ind~stry of pl~ners, Fo~rr pl~ner~ s~cial lathes, ~n t~e mining industrY tor the dri~es o~ min~ hoists, in paper industry f~r electric ~nd ~i~5el ~lectri~ ~QC~mG~iV~S~ its e~icieneY is enormou51~ anfavoraou~le~ n~eds mueh ~ace and ~arce inves~ment cost5, Further ~.rgu~en~ ~ainst its ~plieation~
th~t now~ays with ~he help ~ the U~-tG-~ate cQnv~r~er ~ont~Qlled spe~d rQ~s~tio~5 ~uch e~y to handle electric dri~es can ~e de~elo~ed~ which m~ ~e ~e~i~ned for ~nY ~s~er r~tin~. its ~p~ce de~and i5 li~ted. But in such drives the coct ~f the ~ntr~l electroni~ and u~her equipment ic th~ multiDle o~ th~t o~ ~h~ r~t~ing elec'ric ~achine ~.nd ~e~des this, ~he network is p~llute~ ~y the unw~nted reactl~e ~urFent ~nd u~per harmonics~

2~`7~g.?s5 ~, Thus with the inventiOn it is ai~d t~ reali~e such a circuit arrangement! which is 5uitable for the braking ~f ~ ~ontrolled fo~r-qu~drant drive~ whi~h ~e5ide5 eliminating the disadv2nt~gec of the ~fore di~cQ55~ed kncwn ~olutions, i~ wor~ins with great operation~l c~fety~ has sm~ pac_ demand energy consumpti~n and in~est~ent co~ts. ~y~the extencion o~ the semic~nductor~ speed ~ontr~ of the JriYe the invention ensures with the help ~f the feed-~ck ~rinci~le the adj~tabl~ br~kino at c~rtain e~c~d in ~1} such aces~ when the current c~nsumDtion of the drivinq ~otor ~rr~s belQw ~ discreti~nally ~di~.~t~d v~lue, The bas~c ide~ of our in~en~ion recults from the reco~nition~
,hat it miah~ ~e advant~qeou5 to rea~ize the two taC~ o, c drive srst~m - th~ ~cceier~tion Rnd the slow - down~ i.e. the drivinn and ~he brakin~ - by ~pplyinq two mechanicall~ oo~pled machines.
which from each other el~ctrirally c~mplete~y inde~endent m~chine~ c~lld be m~u~ted in~Q a commcn ~hin~ h~in~ rther-IT~Qre ~h~ ~mo~nt of the curr~nt flowina in the r2torcircuit~ its directi~n and rate of ch~9in~ ~nd the ~ngu~ar velooity o~ the ~haft Q~ the drivin~ motor repcctive~y ~re ~iving inform~tion or a signal suitable f~r feed-back purpo5e~ about the momentane~us l~ad torque ~nd acco~ding t~i5 ~h~ drivin~ mo~or to~ether wi~h the to it mQchanic4lly directly Dr throu~h a ~e~r r~t~o tran~i~sion co~led au~l~iary machine can be braked in~rtiale~
and elast~ca~ly~ if the ~r~king i5 c~rriD~ out ~.~cordi~ ~he purpose i t serve~.
Th~s the ~imeg ta5k i5 5~1v~d ~y th~ ~pplication ~ ~ circuit ~rr~ngem~n~ whieh i~ 5uita~1~ f or the c~ntrol of the brAking of a fo~r ~uaJrant driYe which c~n~istc of two e~ectric machines which are ~o~nt~ ont~ a co~mon ~h~t! which ~ri~e c~nsists o~ ~n ext~rnal ly e~e~ ted d-c- ~rivin~ motor and a br~kinQ ~enerat~r~
~hieh i~ co~led ~ir~ctl~ or ~hrough 2 ~ear ratio trancmissi~n to it ~nd Whi~h br~k ~ ng g~anerat~r h~s; ~ ~ator with saliDnt: Fo~es excit~d with d.irect eurrent.
~ ccording the invention this has under~one to such an i~pr~ement! that the rotDr of the ~en~r~t~r ~ 9~ed circ~it ~a~n~ at mo~t a YerY ~mall ~mp~dance ~nd into the ~2in c~rcLIit Of the dri~ing mot~r a r~tor curren~ s~nsor ~t~ge i5 inserted, 2~ s~

which ~-~tar c~rrent chanqe~ i~rooortlonally ~ith the torQue of the drivina mO~Or cha~Ft. This ~-urrent sensincl a~nDlifier ~5 connected t~ a ce:~mparat~r In i t and to the output terminal 5 ~sf the con~par2tor the excitativn coil ~f the oener~.~or is connected~
which tc~gethe~ with tS~e compa~t~r ~lnit and ttle current sensing device end thro~.lgh the F~lar1tY ci?~nce swit~h - wltich is ~ deter--minin~ the direc'cic~n ~v~f ret~ti~n of the driving IT,otC~r - tocether with the ~citation coi~ ~f the driving motor. is conr,ected to the contro~ eurrent sourcer ~ ccordin~ tD on~ of the faY5~urable realization~ of the cireu~t arran~cment ~f the inve-ntion to the curr~nt 0~5ervin~ resistance the cur._nt sensing device with itr= emitter the base of P~P
transistor is conne~ted! w~ich tri~.nsi5tor is eonnected to the positi~ve t~r~lnal o~ the ~ontr~l eurrent so~lr~e ~nd the cellector of the tr~nsi~tor i5 connected to the first ~wit~hin~ tran~istor of the c~parator Lmit~ the emitter o~ ~hieh ~o~ether wl~h the coll~ct~r ot ~he sec~nd ~tchin~ tr~nsictor is ronnect d to th~
positiYe t~eminal ~f the ~ontro~ current so~rces! it~ c~llect~r ~s le~ to thP ~a~e ~f the l~ter ~nd one ~ the terminal~ n~ the c~mparator. excit~tion coi~ is eonnected to thQ en~ittYr which~
the ~ut~t of the 5econ~ 5witching tr~ns~ ctor oo~rator~ which ~ith its other outpu~ terminal i~ ~onnec~Pc~ t~ the n~g?ti~
tern~in~l uf th~ contr~ cur}ent sourc~?, furthern~ore it is --onnec--~e~ w~th the out~ut terminal of th~ vol tas~e devider re~ist~n~e c~
t~ h,?.~e of the f irst swi~ching ~ransistar .
5in~i~a~1y~ it 15 adv~nta5~e~3u5 fc~r thY increase of the cunsltivitY, if ~ither bet~een the outp~t ter~nal of the current c b5erY~tion re~istance o~ oir~it arrehqement and ~he b2~e of he transistor o~ ~h~ curre~t 0~5erYing uni~ the voltaqe g2ner~tor is cQnnect~d~ wAich vol~e ge~2rator produres th~ Pr~r~ Ql~ge .~ which thQ ~0~ rop on the current Q~serYing resistance is ed~ or bet~een the output t~rminal of the current rb~_~viny re~ist~nce ~r,d ~he b~ of the tr~nsist~r ~ the ~urr~
~ser~ng ctag~ - simila~y to .~he ~ransistor Q~ th~ compar~tor unit - one m~re ~pli~ying unit is connect~d~
Th~ ai~Qd task has be~n eolved by such a circ~it ar~an~emen~
in wh~ h ~C~F~in~ the impr~e~nt~ t~ closed circuit o~ ~he ~ .

2~7~ S~I.

genèra~or rc~tor has at mD5t a very sm~.l 1 imPedanc~ ~nd th~ shaft o~ the dri~ing m~or in me~hani~al connection with a angular pc;sition sender~ which i5 in c:ol~nection with that c~mparatar unit whicl~ is detectiny the inver5ely ~r~F~ortiortal v~riations of the mot~r shaf I ~peed an~ the load tc:>r~ue!, and to the out~ut terminal~ of the co~parator unit thF~ 6~xcitation coil of the ~er~rator i5 conne5ted, whse17 tQ~ether with the com~2~r~tor uni~.
the current sen5ing unit and throu~h the p~l~rity ~h~n~e 5~itch -- which is determinin~ the direl:ti~n c~f rot~tiDn of ~hE? driving m~tor -- to~ether with ~r~ exci~.ion ~oil o~ the driv1ng mQtor i~
~onnected to the çon~rol current s~ur~e.
In the l~tteo c~e it i~ ~dYan~_gec~us. if the _ng;,l ~r pe5iti ~n ~en~er is~: that Qptical an~ular ~05ition senl1er which ic f~7~unted on-Q 'che dhaf t clf the gen~i?r~tc~r~ Pccordin~ a further re~ ation cyste~n of the~ inventiQn it i5 advant~geous if t~,e r~t~r of the braking generator i5 sho~tcirc~.lited. 'che hell~ O~r which the IT~o~t effective br~king cart be re~l ~ zett~
It i~ the grs~ates~ advantaae of the circus~ arr-.r!~o~ene~ c~1;
the inventson that it ma~ce5 ~he in~ertialec~ ~r~king po~ci~le - wi~h the ~est ~fieie~cy ~mon~5t the known ~olutions - o~ a dri~ing motor of di~crQti~al nowPr ratin~ ~u~pl' ed ~i~h discretiOnal 5~:!eed ~ con~rDl O t h~ brakin ef te~ has no t~2~k 9~tion5 to the netwurk at ~11~ ~h~ came ti ~e ~he cir~uit a~ran~ement i5 extremely ~imP~! it c~n b~ ~sembled f!~m ~art5 2a~ avai~a~le ~rom 5h~ps ~nd ~tar~ re~ectiYely. I~ i~
cpecial a~vant~g~ of the circuit arrange5~ent, that it will ~Q'CO~
f25.~r and m~re ~lexible by 'he cDntrol of the bre5king~ bec~uce whil~ e.~. in ~h~ case of ~ ~ard-Leonard dri~e. the ~r~kinc ~ecom~ eff~ctiVe only then~ wh~n the load tor~ue ~auses t~e drivina m~tor ~n e~ceed i~5 ra~ed speed to ~ush an e~tent that ~e eo~nter e.m.f. o~ the m~tor ~ill exe~d the vel.~e remarkably unti l t~en with ~h~ cireuit arr~ns!ement ~f the inYention ~ e hre~kint3 b~eme~3 eff~ctive alrea~dy th--n~ wh~ accordin~ the pre~e~lY ~d,iusted trech~ld valuqr., the currPnt o~ the c;rlvinc motQr rmat~e ~op~ ~ow the pr~adjusted l~Yel ~r it ~e~-he~
it. It 1c ~n iadvantaae~ th~t ~ the ?~rpo~;e ~f t.~o ~rekinq, generator ~ny extern~lly ex~i ed d . c. m~ ~r is =-uit~le~ the 2~ V~,Sl.
pQWer ratinq ~f which ~5 deDendine fr~m the power demand of the ~rive and th~ mechanical Qear ratio trangmi55i~n coupli~ ! which ~e~aves durin~ the resistance bra~ g as ~ qenerator. ~r th~
pr~per ther~al desion o~ the oenerat~r and by ha~ing choosen proper ~ear r~tio tr~n5mi5sio - accordinR the e~perimental set9 of the circ~i~ arranaement - deDendine on the rotor realization the driYin~. ~he braking o~ the mot~r can resul in the full s~o~pin~ ~ the ~otor, moreover ~t st~nd~till it can el~ctri~al 1Y
~e fi~ed. the ex~ atiQn of which ls~ that ~he excitatio~ cOilc ~f the sa~ient ~le5 o~ the ~enerator actin~ as electro~ao~ets are kae~ing the po~e5 o~ the rotor With ~ lar~er f~rce by the develo~e~ m~e~etic fi~d a~ the twi~ting tor~-~e of the drivin~
motor does it.
The adv~nt~e of the circùit arran~ement ~ccordin~ the inventi~n ~gainst all known o~n~rolled drive sy~temc is. that it i5 no~ loading fhe network either with r~stive current n~r w~th =udden current pea~s~ n~r 1~ it ~}lutine the notwork with u?Der ~a~m~ic vQlt~qe p~k~.
~ xtcomin~ t~a invention will expl~ined in m~re deta11 with the help o~ a drawiny~ where the circui~ arr~nee~e~t i5 deman~f rated ~i ~n ex~mpi~.~T~ dr2winc~ i l lus~rat~s the ~ ck--diagr~m t;~f a pos~ le r--21ization exampl~? ~f thQ invention~ and Fi~.2, ~h~ws in more detail the circuit ~rr~ng~tnent oF Fia.l.
}ock--diagra~n o~ Fi~.l. ~hows, that the externally ~axcited drivin~ nn~tc~r and th~!! in ~he ramo wi~y ex~ernal ly 6!xcited 2 Q~aner~tor are CDLlpled mechanic~l ly dirs?ctly tc~ l3ach other. Tn the pres~nt ex~ple the ~ drivin~ mOtOF is the m~tor ~f an elevator Whi,~:h i5 1~0~ dQ~nOnC~ra~ ~d irl the ~rawinq, at whict~ the e~terna~
~oi~ ~ue ioading thq~ sha~t o th5~ driving mc~tor ean be in both ~irect~on~ of r~tati~n of PQ2iti~e ~r ~e~tive sian . The ~r -~af~r~ windin~ Q~ t~e 1 driving mutor i5 dir~ctly c~nnected t~
~he ne~.tiv ermina.l of ~he U~ F~wer sQurce. ~hrou~h the current s~nsing ctaa~? hQP~ever it is eonn~ted to ~h~ poziti~
~-rminal of ~he U~ ~o~r 50urs;e .. The armatut-e windin~ of f he erætc~r i5. ~ih~t~ir ~ited thrsugh the Rf br~kina resi~startce.
The R e~ci~tion coil of ~h~ 1 drivinu mCtQr is 'chrouah the ~C
gm ~
~ol~ritY changina swit~h c~n~ected to ~he ~o~itive ~nd n~ative . ~-: ,.....

2~
t~?r~m~n~l ~f the currer t ~our~e ~hich ~rovides the U ~ntrol ~lta~e. Th~ outPUt of the ~; current 5ensing unit ~ s conneate~ to the inPut of the ~ c~n~parator unit. one OlltDUt terminal of which is connected to the other t_-~min21 of the R excit~tion cail of .. gg the 2 gereratt~r whiah i~5 ~onne~ted tc the negat~ve ter~T~ina1 ~1' the U . In ord~r t~ ensur~ power ~;uD~ly the ~ current sensing uni~ ~5 wel 1 as the 4 ccmP~rat~r unit is conne~ed te the ,~sitive and neSIatiye ~ermin~.15 o~ ~he Uv control vo1taQe, Q~ well in Fit,t.1. ha5 been india~ted sueh a variant ~.cc~rdin~
the invention. where ~or ~he contr;~l of the brakinc of the four quad-an~ drive n~ he current ~f ~'-e 1 dri~ina motor arlnature ic ~r~vided. In thi5 ~ace ~ltpu~ o~ 5 ~ngul~r ~esition 3en~0r mounted ~ither bnto the s~a~t of th~ 1 drivino motor or of t.~a~
of tt~e ~ ;3~ner3tor i5 connect~3d to the in3ut of the ccim~ra~Qr ~nit . This v~ri~n~ is indi~a~ed in Fi~.l. with dott~d lines.
In ~he e~amp~ ~ 5hcwn Lh~ Y~lu~ e~ the ~f b~r~kincl r~sist~.nce is 0~ thu~ the rotnr n~ t.~te 2 ~en_rator i5 5horts~ rcuited. the short circuit current i~ limited only by the R~ interna~ r~i5tan~e of the 2 generatOr- By Varyin~l the ma~n ~ ~c'e o~ the F~f ~raking resiistanee th~ braking ch~c!~eris~ic of the 2 aeneratc~r can ~3e altere~ $ increaSin }~ brakin~ re5ictance V~lu~c the ~r~king char~cteri~tiC ~ill be ome ~s~ter.
~ n ~ig.~ ore detailed cireuit: dia~ram i5 shown ~o~t the blo~k-diagr~m given in FiÇ!~l- with~n this ~ttQt~t the ~ curren~
sensin~ unit ~nd the 4 ~o-Ttparator unit as well. It i5 empha~ized"
that th~ circuit di~gram 5hown here i5 only one of ~he ~ossi~le ~olutIons~ the dif~ren~ re~li2=~~ n ~f the individ~l ~nits does not c~s ~ ~ny diffiCUlt~e5 for an en~in~er or 2 teshnie,~n.
The 1 driYing ~TtQ~ i5 thr~h the R ourrent obserYin~
r~sistance c~f ~he ~ curr~nt 5ensinq unIt connecte~ ~o th~
~si ~ive t~rminal ~ the U~ power 51.1pply . In the examD1 demans~rated fh~ F~ iy~ ter~ina~ a~ the U~ power supply is in ~o~!mon with fhe p~SitiY~ ~rminal of ~h~ U~, control Vc~T ta~e. rhe s~rrent ob~ervin~ r~sistance can ~ ~ sin~le and ~ ionsly even a YerV 5~ 11 val~e re5i5.~nee, but it can t2~ reali.ed as a potentioa:eter a~ ~ell! in thiei case the 3 current ~ensins7 ~ni~
W~ll Dbte~in ltg; cantrol si~nal from thE! slidin~ c~ntact of the R

2~
eurrent obsRrvinQ resi5~ar~e. ~s it c~n be seen from the drawin~
the 51 idin~ contact Df the R" curren~ ~bger~in~ resistance on the 6 volt~e 6!~nerator -- which is Droducin9 the prestresS ~olta~ae wich is edc~ed t~ the control vo~ tage produeed by the R
resistance - connected ;to R~ ba5e re~istance Df T~ transist~r of the ;; current sensint7 unit- The c~l lector of the ~ P tS~pe Ti transist~r is the o~tt:~ut 9f ~ current ~iene?n~ ~Init~ which 15 conns~ted tc~ the in~t of the 4 com~arRtor ~snit. i.e. ~ the ~a5e of the T2 switehine tr2nsi5tor. The T2 ~witchin~ t~ansistor ~
connected throu~ the ~ ~a5e resistarlce to the volta~e ~evi~er output. which is re~lia:ed l;~y the PL potentiome~er! while ;Lts emi~ter is eQnnert~ to the yositiv~ t~r~inal of th~ U contrsl vo}t~e~ it5 ~ollectQr h~wever ~5 connected throuRh ~3 base reeistance to the ba5e of fhe seeand T3 ~witchin~ tr2.ns~star . t~_ emitter sf th~ ~3 ~wi~ching tran5i5tor is to th~ ~ositlve tern~inal of the Uv e~trvl vo~t~lge connecte~tl. it~ collec~or whl~:h is the ~ut~ut of th~ 4 c~m~r~tor unit i~ connecte~ t~ one o~ the termir7~C of the R excit~tion coi~ of the ~ ~enerator. ~n ~h~?
pre~rnt e~m~le to ~he eollectDr of th~ Tg swit~hin~ transis~er ~hrough th~ R4 5erie5 re~istan~e ~he LL1 ligtt emittin~ diode ~5 eonne~t~d t~o which is connected a5 w~ll to the ne~tive terminal ~f the U eontrol volta~e.
The circuit arran~em~nt aeeordin~ the inventi~n is work in~ as fo~l~ws: .
Th~ ~rm~tur~ ~f the 1 d~ivin~ ~3tor dependin~ vn ~he even ~ctual bui~-u~ ~f thl3 ~rive i5 eith~r connected t~ a constan~ U~
Yolta~e sourcc or to a know~ ~ - mi cDnductor s pced con tro l i ini t ~
e.~. t~ the output ~f ~ reetifier ~nit ~hich prt~d~ces ts ~upDly volteg~ The ~m ~xcit~ti~n coil of the 1 d~iving ~!~tor is throuCth ~ho K pol~ri~y 5witch - ~hich ~witeh is ~ctDrding ~he re~uir~g speed direc~ion Dut in o~e or an~th~ ~ositi~n - eonneO-te~ ~o th~ Ll ~ontrol vslta~e. ,he c~rrent of the ~r~ue produclng 1 ~ri~in~ m-'tor ~ 5 f lowing thr~u~h ~he R current o~serving resist~nce ~ ~he ~ ~Lirrent sen~in~ ~nit, ~e~endin~ ~n ~h~ maur~i~ude of the current~ there will ~e a volt~qe drop on the R current ~bservin~ re5i5tane~., which v~ltage drQ~ c~nncc.ed int~ series wit1? the adju5tab}~ ~lta~e having ~he ~-me pol~r~ty 2~.' W~

of the b ~olt~ae aenerator wil1 ~e led to the ~a~e of the T
~ransistor o~ the ~; ~urrent ~en5in~ unit~ The ~ase curr~nt of the r~ transi~tor is seleeted in such a way that it is con~roll~ng i~to ~ul 1 ~enin~ t~e ~ transistor. th~ls i~ i5 shuntin~ ~e base-emitter se~tion o~ the T2 tran~istor of the 4 ronpar~tur ~tace. ~5 ~?. eonee~uence the Tz 5~i~0hin~ transist~lr is ~ sin~
and is k~ep~n~ clqsed the 5econd T3 ewitchin9 tran~st~r as ~ell whieh aDpears in thi5 w~.y ~5 an open circuit in the circ~it ot the R e~cit~.tion coil ~f the 2 ~ener~tor. Thus the 2 ~enerator h~vin~ a short rircuit~d ro~o~ and no ~xcitati~n i5 rotat~ng freely without de~el~pin~ ~ hrakinq torque, I ~ the ~ ~r~ue of the 1 generator i5 ch~n~inq in ne~2 ive dire~ti~n ~he ~rrert tlowin~ in th~ arm~ture ~f the 1 ~r~v~ng motc~r wil 1 ctecre~e 2nd halvinl3 f~lrther change in the s~me direeti~n in the lo~d tclr~u~ it wil ~ decre~se ~?ver~ tQ 0~ and re3~t the direetion o, the current w~ll r4Yer5e. Dependin~ on the contrQl velta~e le~e~ which is nece55~ry ~or the actiy~tion of th~ 3 curr~nt sene~n~ Sta~ ~nd devi~tiong ~r~m the ~ol~ions known nowad~ys ac~:irdin~ ~h~ ~ircuit arrangem~nt o~ tl~e inven~ion . here i~ nD need to wait until the current ~ the 1 drivin~2 motor drn~s to ~ or ~h~ rever5ina Qf~ ~t5 ru~ent, but the decrease ~
~he val~2~edroP deveioped Dn the R current sensin~ re~istc~r i5 ~1 re~dy en~llgh or ~he deere~siiQ of the ba~e current o~ transiC~cJr J . o ~ ch a v2~ue where tr~n5istor T~ is ~lready clo=ril,~ . d~wn~
Then the chunt--ef fect o~ tr~nsastor T1 ~e~w~en the b~se~mi~ter section ~f T2 CWitCh~r-Q transis~or will C~ti3L5e 2n~l ~t the base of the T2 switch~n~ tran5i5t~r thrQuclh ~he R3 b~se resist~nce ~l~
~pen~ns~ Yolt~e will apc~ear the m~.~nitude ~ which is ad~ucte~ by the P pct~n~cnn~tar. The bace ~rrent of T2 switch~ng tr~nsistDr i5 9~Y~rning ~n~ ~pen 5ta~e the T2 ~witching transistor ~nd an eifect of thi~ the T3 switchin~ tr~ns~istC~r i5 ~pening es well and thu~i it ~s s-~itchina th~ R~g e7~citation ~Dil D~ ti-e 7 ~enerator to the Dositi~e term-na} of th~ U con~r~l v~lt~e. The 8e~er~or i~ Gbtaining sl~enly maxim~m e~ci~atlon ~nd i~ ~hQrt eirc~it2d rot~r ~ue to t~e deve1~ped m.m.~. exerts ~uddenly a ~trona ~r~ n~ ~0-5u~ Qn~o the ~haft ~f the w~h it ~,e~hani~lly couple~ ~ ~riving mo~r. A5 ~ c~n~e~l~en~e the ar~at~r~ current D~

2~ 5:1.

the 1 drivin~ ~otor ~ill increa~e ~ain ~nd 'he v~lta~o dr~p ~evelo~ed on the Ro c~rrent ob5erving resistance will o~en without ~lay. the tra~5istor T~ of the current sensine sta~e and this in t~rn i~ ~1~5in~ down the T3 5w~tchin~ transistor ~f the ~
current sensing s~a~ ~nd thuc th~ e~citation of the ~ ~enerator wili cease. ~y the adjùstement of th~ ~I potentiometer of the 4 compar~tor s~a~e thi5 thre5h~1d limit can be ~djus~e~ at ~hich the Tz tran~istor 5t~r~5 to kec~me oFen. F~lrther ~ossibil~ty ~or ~e adiuctmen~ ic ensure~ by th~ application of a ~otentiemeter as R cur~ent observing ~e5istance~ the h~lD of which the threshold vDlt~ee ~or the T~ tr~n~i5t~r of the ~ eD~i~2 ~tage _an be adjust~d~ The v~lta~e drDp devel~ed on ~he ~ currDnt ob~erving resist~nce w~i~h ~an ~e regarded from th~ n-~in~ o~ view of the 1 drivin~ mQtQr un~mbi~ou~ly a~ 2 105C ~ i 5 ~is -~dvan~ge~u5- therefor~ it ~5 advi5ab~e ~ deEion i~ ~or es small as po~sible. ~t th~ v~tage dFop ha5 to bP ~reat enou~h op~n ~p .he T~ transistQr o~ ~he ~ seneing ~aae. ~hic s~e~}na c~ntr~diction can be dissQlved ~y the 6 volt~ge ~n~rator~ the he~p o~ ~hich a ~restres~in~ velta e which i5 of c~nstant value~
and i5 cDnne~ed in 5~rie5 with ~he ba5e v~ltage ot the T~
transistur havin~ openin~ direction is inserted ~e~een ~he Q~tp~t of the R current o~rving rasict~nce ~nd .he ~ hase re~is-ance of the ~ tran5i~r~ dvi~le te ~ele~ ~he out~u~ ~u}taye ~f 6 vo~t~e ~enerator to 5uch a v~lue th~t it~elf it ~hould be ~abl~ t~ ~avern into open T~ transis~or! ~n the other hand con~ected into eerie5 ~ith the very ~a}1 volta~e droc ~evelop~d ~y R current ~b~erYiny re~i~t~nse it is ~overnin~ T
~r~nsi~t~r l~edia~ely into ~n st~ e. Th~s it can be seen~ ~hat ~n 5~ch c~e~ a very sma~l voltage dr~p-~ut and ~ ~ery ~all ch~nge in volta~e ~rop r~5DeC ively i5 sati~actory for the ~wit~h on and ~ut re5pecti~1y of the ourrent ~en~ir,~ stan~.
It c~n ~e seen fr~m t~D demQnstrat~d ex~le 2s we~ h~t be~id~s ~h~ e~treme~Y simplr~ bui}~-up of ~he ~ir~uit ~r~n~ment of ihe inv~nti~n it i5 fulfi~lin~ ~cellcntly i~5 ~ o~ t~5~;
with the help ~f th~ br~ki~Q gener~tcr it '5 a~le tQ nerfor~
~n~ ~e~Se ~he ~r2~n~ of ~he ~our q~d~ant dri~e rsr ~e~n~5 even ~en timQS~ wit~out del~y~ reliably. This ~ Jener~or oan ~e 2~.`7~.~5~
desian~d as a fLIn~tion of the mechanl~al q~ar r~tio which i~
bet~een the 1 drivin~ motor and 2 gcnerator~ thus it is br~king tt~e 1 driving rnotor with g~30d e.fficieney besides havin~ small sizes and smal 1 power demand .
Obviou51Y ~here mi~t~t be such cases ~f app' i~ation . wher~e the rough.. sLldden drakirg is not de5irable, in such cases ~ an R~
brakin~ resi5tance ~ ving 5u~ table value for the set aim - has be inserted nto the armature circuit D~ the ~ gene~ator.
At the described e:~a~ples the 4 comparator stas~e is hy~terisi~ess,. but the application of a 4 ~Oml:?arator stage havin~3 an adjust~l~le hy5tere~i5 a~ the ~iverl F~laae of the circuit . does net cause ;itny dif~iculty.

Claims (5)

1. Circuit arrangement for the control of the braking of a four quadrant drive which consists of two rotating electric machines mounted onto a common shaft, which drive contains an externally exited d.c. driving motor and an externally excited d.c. braking generator which is connected to it mechanically directly or through a gear ratio transmission, characterized as such, that the generator (2) armature is created with a braking resistance which has small impedance as a closed circuit and into the armature circuit of the driving motor (1) an aramture current sensing stage (3) is inserted which is observing the armature curren, which current is changing proportionally with the torque of the motor, which current sensing stage (3) is connected to the comparator stage (4), and to the output of the latter the Rgg excitation coil of the generator (2) is connected, which with the comparator stage (4), the current sensing stage (3) and through the polarity changing switch (K1) together with the Rgm excitation coil of the driving motor is connected is connected to the control voltage.

2. Circuit arrangement according claim point 1. characterized as such, that to the current observing resistance (Re) the base of T1 transistor is connected the emitter of which is connected to the positive terminal of the control voltage (Uv), the collector of the T1 transistor is connected to the base of the first switching transistor (T2) of the comparator stage (4), the emitter of which united with the collector of the second switching transistor (T3) is connected to the positive terminal of the control voltage (Uv), its collector however is led to the base of the second switching transistor (T3) and the emitter which is the output of the second switching transistor (T3) comparator stage (4) is in connection with one of the output terminals of the excitation coil (Rgg) of the generator (2), whic coil with its second terminal is connected to the negative terminal of the control voltage (Uv), furthermore it is connected too with the output terminal of the voltage devider of the base of the first switching transistor (T2).

3. The circuit arrangement according claim points 1. or 2.
characterized as such, that between the output terminal of the current observing resistance (Re) and that of the base of the transistor (T1) of the current observing stage the voltage generator (6) is connected which is producing the prestress voltage which is added to the control voltage which is the voltage drop on the current observing resistance (Re).

4. Circuit arrangement for the control of a four quadrant drive containing two electric rotating machines which are mounted onto a common shaft, which drive contains an externally excited d.c. driving motor an externally excited d.c. braking generator which is connected to it mechanically directly or through a gear ratio transmission, characterized as such, that the generator is created with a braking resistance which has small impedance as a closed circuit and the shaft of the driving motor (1) is in mechanical connection with an angular position sensor sender, which is in connection with the comparator stage (4) which is detecting the with each other inversely proportional variations of the speed of the driving motor (1) and that of loading torque and this is connected to the output terminal of the comparator stage (4) through the polarity changing switch (K1) united with the excitation coil (Rgm) of the driving motor (1) it is connected to the other terminal of the excitation coil (Rgg) of the generator (2) which is with one of its terminals connected to the control voltage (Uv).

5. The circuit arrangement according claim point 4. characterized as such that onto the output terminal of the current sensing stage (3) the control electrode of a switch-off thyristor is connected, the anode of with is connected onto the positive terminal of the control voltage (Uv), its cathode however is through the Rgg excitation coil of the generator (2) connected to the negative terminal of the control voltage (Uv), and the output terminal of the current observing resistance (Re) of the current sensing stage and the base resistance (R1) of the transistor (T1) is connected to the coltage generator (6) which provides the prestressed voltage, which is connected in series with the control voltage developed at the current sensing resistance (Re) with opposite polarity.
7. Circuit arrangement according claim points 4. and 5. charac-tererized as such. that onto the output terminal of the angular position sender (5) the control electrode of the switch-off transistor is connected. the anode of which is connected to the positive terminal of the control voltage (Uv), its cathode however is through the Rgg excitation coil of the generator (2) connected to the negative terminal of the control voltage (Uv) and the output terminal of the current observing resistance (Re) of the current sensing stage and the base resistance (R1) of the transistor (T1) is connected to the voltage generator (6) which provides the prestressed voltage which is connected in series with the control voltage developed at the current sensing resistance (Re) with opposite polarity.
8. Circuit arrangement according any of the claim points from 1.-7. characterized as such, that the armature of the generator is short circuited.

.