International journal of


EISSN: 2313-3724, Print ISSN:2313-626X

Frequency: 12

line decor
line decor

 Volume 4, Issue 12 (December 2017), Pages: 73-78


 Original Research Paper

 Title: A multistage AC-AC converter designed by using switched capacitor techniques

 Author(s):  Kei Eguchi 1, *, Wanglok Do 1, Soranut Kittipanyangam 1, Kanji Abe 1, Ichirou Oota 2


 1Department of Information Electronics, Fukuoka Institute of Technology, Fukuoka, Japan
 2Department of Information, Communication and Electronic Engineering, National Institute of Technology, Kumamoto College, Kumamoto, Japan

 Full Text - PDF          XML


To realize small and light ac-ac converter, a switched-capacitor (SC) technique is one of the most promising techniques, because heavy core and windings are not necessary to design the SC ac-ac converter. In this paper, a multistage direct ac-ac converter is designed by using SC techniques. Unlike conventional SC ac-ac converters, the proposed SC ac-ac converter consists of N (=2, 3, ...) converter blocks with symmetrical converter topology. To achieve high step-up/step-down gain, an input ac voltage is converted several times by the series-connected converter blocks. Due to the symmetrical multistage topology, the proposed SC ac-ac converter achieves not only high step-up/step-down gain but also fewer capacitors than conventional SC ac-ac converters. In other words, the proposed ac-ac converter can improve power efficiency and input power factor from conventional SC ac-ac converters. To clarify the characteristics of the proposed SC ac-ac converter, operation principle, qualitative analysis and simulation evaluation are presented. The validity of circuit design is confirmed by simulation program with integrated circuit emphasis (SPICE) simulations. 

 © 2017 The Authors. Published by IASE.

 This is an open access article under the CC BY-NC-ND license (

 Keywords: Multistage converters, AC-AC converters, Switched-capacitor circuits, Step-up/step-down converters

 Article History: Received 16 February 2017, Received in revised form 1 September 2017, Accepted 20 September 2017

 Digital Object Identifier:


 Eguchi K, Do W, Kittipanyangam S, Abe K, and Oota I (2017). A multistage AC-AC converter designed by using switched capacitor techniques. International Journal of Advanced and Applied Sciences, 4(12): 73-78

 Permanent Link:


 References (9)

  1. Andersen RL, Lazzarin TB, and Barbi I (2013). A 1-kW step-up/step-down switched-capacitor AC-AC converter. IEEE Transactions on Power Electronics, 28(7): 3329-3340. 
  2. Eguchi K, Oota I, Terada S, and Inoue T (2009). A design method of switched-capacitor power converters by employing a ring-type power converter. International Journal of Innovative Computing, Information and Control, 5(10A): 2927-2938.     
  3. Eguchi K, Pongswatd S, Tirasesth K, Sasaki H, and Inoue T (2010). Optimal design of a single-input parallel DC-DC converter designed by switched capacitor techniques. International Journal of Innovative Computing, Information and Control, 6(1A): 215-227.     
  4. Hara N, Oota I, and Ueno F (1997). A continuous current switched-capacitor DC-DC converter with fixed-capacitors and a voltage averaging capacitor. In the International Conference on Nonlinear Theory and its Applications (NOLTA'97), 2: 1209-1212. Available online at: 
  5. Lazzarin TB, Andersen RL, Martins GB, and Barbi I (2012). A 600 W switched-capacitor AC-AC converter for 220 V/110 V and 110 V/220 V applications. IEEE Transactions on Power Electronics, 27(12): 4821-4826. 
  6. Lazzarin TB, Moccelini MP, and Barbi I (2013). Direct buck-type AC-AC converter based on switched-capacitor. In the Brazilian Power Electronics Conference, IEEE: 230-235. 
  7. Terada S, Oota I, Eguchi K, and Ueno F (2004). A ring type switched-capacitor (SC) programmable converter with DC or AC input/DC or AC output. In The 47th Midwest Conference on Circuits and Systems, IEEE: 1: 29-32. 
  8. Ueno F, Inoue T, Oota I, and Harada I (1993). Realization of a switched-capacitor AC-AC converter. In the 11th European Conference on Circuit Theory and Design, Davos, Switzerland: 1177-1180. Available online at: 
  9. You J and Hui C (2014). A novel switched-capacitor AC-AC converter with a ratio of 1/4. In the 17th International Conference on Electrical Machines and Systems, IEEE: 3205-3207.