Vol.105 (4) December 2014 SOUTH AFRICAN INSTITUTE OF ELECTRICAL ENGINEERS 1

December 2014

Volume 105 No. 4www.saiee.org.za

Africa Research JournalISSN 1991-1696

Research Journal of the South African Institute of Electrical EngineersIncorporating the SAIEE Transactions

Vol.105 (4) December 2014SOUTH AFRICAN INSTITUTE OF ELECTRICAL ENGINEERS134 � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �� � � � � � � � � � � � � � � � � � � � � � � � � � � � � �� � � � � � � � � � � � �Mrs Gerda Geyer

South African Institute for Electrical Engineers (SAIEE)

PO Box 751253, Gardenview, 2047, South Africa

Tel: (27-11) 487-3003

Fax: (27-11) 487-3002

E-mail: researchjournal@saiee.org.za

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H I J K L M N O P I M H Q J H R H M NS T U V W X Y U Z Y [ \ U ] ^_ ` a b c d c e c f g h i j k l, Faculty of Engineering and the Built Environment, e m Z m n U Z n ] T U V W X_ ` a b c o c o p q r g

, Faculty of Engineering and the Built Environment, o _ ] [ U m f U o V ] T U V W X o[ a s s j q p h g l p a q t g q u o p v q g w _ ` a h k t t p q v x_ ` a b c f c _ c f p q u kUniversity of Pretoria, SA _ ` a b c o c e g r g ` g yUniversity of Pretoria, SAT ` W c \ a w w g q u

, Centre for Telecommunications Research, London, UK_ ` a b c ^ c V g z g { p ` g, School of Electrical and Information Engineering, _ ` a b c m c | c \ g q } p q h zT ` ] c n a w a ~ p q t

Pretoria, SA[ a s � j l k ` � U q b a ` s g l p a q o � t l k s t g q u o a b l { g ` k ] q v p q k k ` p q v xT ` e c � k t l t l ` g l k �Newco Holdings, Pretoria, SA_ ` a b c m c ~ g q u k ` e k ` { k

T ` [ c ~ g q u k ` � g w lResearch, Pretoria, SA._ ` a b c d c T { a w g l � z �[ a q l ` a w g q u m j l a s g l p a q xT ` d c � j z t k w_ ` a b c V c ~ g q Z p k z k ` z] w k h l ` a s g v q k l p h t g q u m q l k q q g t x_ ` a b c | c \ c [ w a k l k_ ` a b c V c | c W c m b j w w a_ ` a b c X c n k t h r z k] w k h l ` a q T k ~ p h k t g q u [ p ` h j p l t x_ ` a b c e c u j _ w k t t p t

University of Pretoria, SAT ` T c ^ a l �, Gilgamesh Associates, LLC, Vermont, USA] q k ` v � g q u _ a { k ` o � t l k s t x_ ` a b c e c T k w p s g `] q v p q k k ` p q v g q u V k h r q a w a v � e g q g v k s k q l x_ ` a b c | Y \ c _ ` k l a ` p j t

, Faculty of Engineering and the Built Environment, _ ` a b c f c _ ` k l a ` p j tPretoria, SA

] q v p q k k ` p q v p q e k u p h p q k g q u d p a w a v �_ ` a b c | c | c \ g q k z a s �University of Pretoria, SA _ ` a b c ^ c X g l l g � �

Vienna University of Technology, Austria_ ` a b c d c d a q r g s � University of California, San Francisco, USAn k q k ` g w V a � p h t � ] u p l a ` t Y g l Y w g ` v k xT ` _ c | c [ p w w p k ` t �_ ` a b c e c m c ~ g q � � z

, School of Electrical and Information Engineering, U Z V ] X Z m V U W Z m f _ m Z ] f W ^ X ] } U ] � ] X oW.A. Brading, New Zealand

The University of Birmingham, UK

Prof. J.A. Ferreira, Electrical Power Processing Unit, Delft University of Technology,

The Netherlands

Technical University of Darmstadt, Germany

C.F. Landy, Engineering Systems Inc., USA

Prof. D.A. McNamara, University of Ottawa, Canada

Clemson University, USA

R.T. Waters, UK

T.J. Williams, Purdue University, USA_ j � w p t r k u � �Tel. (27-11) 487-3003, Fax. (27-11) 487-3002,

� � � � � � � � � �Dr Pat Naidoo� � � � � � � � � � � � � � � �Mr André Hoffmann

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