X-RAY. 6a#LRAL. TECHNICAL INFORMATION SERl ES Title P8ge. / A* D~U~OUCOSW-890 Series Transformers. - wr-193 REPRODUCIBLE COPY FILED AT

Transcription

1 0- c X-RAY 6a#LRAL TECHNICAL INFORMATION SERl ES Title P8ge GEPf-- 77L9b/o41? SUeJLCt C W W l C A T l O N AUTHOR I / A* D~U~OUCOSW-890 Series Transformers NO. R40XEl.2 o*t(i wr-193 MALVA!tWV? OF MAGNETICS, IN!. CORE FOR POWER SUPPLY T1TL.I PIm Rulli TRBESSF'OBMB SECQPSD SOURCE A ~ S T R A c T (PE-14) (E S E - ~ ~ ) The EEI was run t o establish a second source f o r toroidal core, 118~1217P3 and t o establish the effect of saturatfon flux density on oscillation frequency. This report sunnaarizes the results of the pilot run, and of laboratory tests perforrned on the core characteristics. G. E CLASS GOV. CLASS 4 REPRODUCIBLE COPY FILED AT Technical Data Center P. 0. Box NOHE St Petersburg, Florida CONCLUSIONS NO. PAGES 6 Magnetics, Incorporated core part fiw26-id is an acceptable source for 118~1217p3. (Incorporated as second source on 3752). INFORMATION PREPARW mn Engineering QC/Ehgineering - A. - EWR - ESE-J3,,EH-lg3 Dounoucos Electronic Systems Eugineering D,Y,O,ON InBustrial Electronics LOtATLON St. Fetersburg, Florida

2 DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document.

3 This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

4 X-RAY DEPARTMENT GENERAL ELECTRIC COMPANY TECHNICAL INFORMATION SERIES CONTENTS PAGE CONTENTS OF REPORT NO. PAGES TEXT NO. CHARTS DRAWINO 7 NOS. PHOTO NOS. 6 Hone None DISTRILLUTtON SAHDIA BH WF TS JJ RT AI? Bfschoff Dc Brown PF Brown VT w.ul.kett LW Mxon ' Btteffel Carstens 3423 Church 1410 Da;vson 1414 &Pew 14ll a4 Gabriel 2542 SP shogp AI?' Persons GP Rtersen LF Robinson HR Sine W! ' Stapleton FE Steele D Weinberger %chnicd Data e n t e r (5) AEC JH Sund -2FL. 335A 1413

5 0 TABLE OF COKPEZ4TS

6 I. INTROBUC!PION This p i l o t man was i n i t i a t e d t o evalnate a second source f o r part number 118~121.7 p3 which i s the power supply transforruer core.!this core has been a sin@e source i t e m purchased fro= Arnold mgineering Inc. of Wengo, Illinois. The s o m e being eml'uated i e m e t i c s Inct who make essentially the same liae of toroidal cores as Arnold Engineering. 11. Much work has been done with the present transfomer core t o establish the effect df core parameters on oscillation frequency. m n t y (20) cores from each of six (6) transfonaer core l o t s were tested i n the Engineering Laboratory t o establrlsh core chracteristicrs, an& l o t performing this work, f i f t e e n (15) cores from t o lot variations. m e t i c s Inc. were also-tested t o compare this product with that of Arnold Engineering. X R charts were plotted by &. C. data and are included in the appendix abi flgr;zres 2 and 3. The charac t i c plotted i s the p a l r flux density obtained a t a 2000 cycle t e s t frequency with a peak magnetizing force 00 1/2 oersted. - Figure 2 shows a comgariso~of values obtained with both Arnold and Magt3etics Inc. cores. Peak flux densities of these Magnetics B c. cores are seen t o be more similar t o those from l o t 50 of the Arnold Engineering group t h a t o other lots. The plagaetics Inc. cores tare within %heblsil\afactt*per's specifications, while the t o t a l spread of the Arnold Engineering cores i s greater thsn claimed by the manufacturer. me effect of pea$ f l u x density on oscillation fiequencgr i s seen i n Figure 3. In t h i s % R chart, peak flux density for each of t h e l o t nuibers shown is plotted from samples of I$ = 2. To the right of this plot i s shown the amrage fiwquency (plotted as the inverse) obtained froba fifty (50) transformers made from cores of the szme - l o t numbers. It can be seen that the oscillation freqyency follows the general trend of t h e curves for peak flux density. However, flu density is not the only variable affecting oscillation frequency. Transf o m r frequency may be expressed as follows: (1) vcc = Primary voltage. f = vcc = &amber of prinary turns. = mxilwm Plwr (Maxwells). &Ep 2Em loo8 + 2VccT1 T1 = Time i n seconds f o r switchidg each half cycle. 3 (1) GE r i i 7, 1958 P

7 As can be seen frorn this equation, primary voltwe, primary turms and peak magnetic flux are the three (3) ingartarit varitibles controllhg oscillation frequency. Since primary turns are very closely controlled, l i t t l e variation framtrkmsfomer t o transfonmer should exist here. As the sane transistors are wed for all tests, the switching time of the transistom w i l l not affect the r e s d t s. However, the zgethod of test involves adjusting the primary voltme u n t i l a specified output voltage level is reached. The primary voltage must then f a l l within spedified limits for the transformer t o be acceptable. Therefore, the frequency data plotted inclndes not only the effect of core parameters but the actual voltage variations occurring i n power transformer t e s t. It was apparent that the spread i n oscillation frequency could be reduced e a flux density. This reduction was agreed by reducing the spread i n p t o by the vendor d was put into effect after lot 50. The narrower spread of frequencies f o r l o t i s the result. - These tests showed t h a t the w n e t i c s Inc., cores have essentially the same s h a p and dynamic characteristics as Arnold Engineering c o p s. A p i l o t run was, therefore, i n i t i a t e d t o verify whether the Mangetics Inc. cores would act as well as Arnold Engineering cores i n corrrplete transfomers. Ten (IO)power transformers were constructed using m e t i c s Inc., cores Their performance was compared t o a control group using Arnold Engineering Cores Each of the transformers was tested per ~ 3 2 2and the following data was recorded: Input Voltage Tas Voltage Compensating Voltage A c t u a l O s c i U t i o n Frequency Control charts plotted f r o a t h i s data are included i n the appendix as E"ic3ures 4, 5, 6, a d 7. The only significant difference i n characteristics lneasured occurred i n oscillation frequencies, w h i c h was expected as no attempt was made t o match the characteristics of Hqpetics Inc. and Arnold cores. It is noted that both groups were within the engineering Umits. It is concluded, therefore, that no significance difference i n power transformer performance is t o be expected when using cores from either of these vendors. v. comclusior Magnetics Inc., core part number ID is an acceptable source for 118M2l7 P3. -5-

8 1. Incorporate metics Inc., a second source for ~ 8 ~ p (Incorporated a~ second source OR CB 3752). 2. Farther investigation shoqld be made? of the efzect of other core pararaeters on power supply gerf'ormance to establish definitive speclfica%ions. -6-

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