Computer-aided design of power processing converters for electric thrusters

Abstract

Thzs paper describes methods for the desiqn of fixed-frequency power processinq converters for electric thrusters. Computer-aided design methods ters lconverters with transformers1 end enerqy storage converters (switching regulators). The results obtained are exemplified by a description of the preindustrialization version of the power conditioninq and control unit of a ccsiw, contact i o n t i irusa re g iYe for Instantaneous energy transfer conyerFor an equal input power, the currents switched are the Same in both configurations but the open Circuit Switch voltage is equal to 2u1 for the push-pull driver and U 1 for the bridge driver, where Ul is the Dc input voltage. TzBlfEi'me_r The primary w i & is a function of the driver configuration and may be either with a centertap lfig.2.3) or without lfig.2b). In the first case the dilty cyle is 50 4 and in the second, 100 3. ~. The secondary winding(s1 can also be with or without a center-tap : the choice depends on the device loading the transfomer. Three tynee Of secondater. The global efficiency lincludinq control cirwatts. CULtS) 15 75.2 9 for an overal l power OUtPllt Of 158 ry winding are defined : Introduction _. .( 1 1 center-tapped. The power processinq requirements of an elec(li) without center-tap, 50 % maximum duty cycle, tric thruster often evolve during the design of the liii) without center-tap, 100 S naxImurn duty cycle latter and frequent re-design work is necessary for I Rectifier the power conditioning and control unit. A l s o . the --------multitude of possibilities for the desirjn of each A multitude of possibilities exists for this individual converter means that some form of compusub-system ; some examples are given in figure 3 . ter-aided desiqn approach is necessary in order to obtain a Solution that is Optimal from an efficiency. inass o r volume point of v i e w . In this paper, we shall describe the amroach adoDted at the LaboraThese Circuits are well-known but w e shall underline a fcw points concerning the voltage multiplier circuits : .. toire d'Automatique et d'Analyse des Systemes du ( a ) They are of interest when the secondary winCent r e National de la Recherche Scientifique ding wire Sire is fixed by winding difficul1L.A.A.S. du C.N.R.S.). tie5 and not by the output current. ib) A symmetric multiplier is best Since it equally 10ais the driver switches and decreases the output resistance by a facter of 3.5 to 6 Static power processing Converters may he classed in two cateqories : l i ) instantaneous enerqy transfer converters over that of an asymmetric multiplier. (Converters with transformers) which enable Dc to AC or Dc to Dc conversion. Fl fo? a square-ware drive s igna l _ _ _._ _. _ _ _ _ -