This paper proposes a Fuzzy Sliding Mode Control (FSMC) as a control strategy for Buck-Boost DC-DC converter. The proposed fuzzy controller specifies changes in the control signal based on the knowledge of the surface and the surface change to satisfy the sliding mode stability and attraction conditions. The performances of the proposed fuzzy sliding controller are compared to those obtained by a classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variation of the load resistance and the input voltage of the studied converter., {"references":["M. H. Rashid, Power electronics handbook, 2nd ed. Academic Press,\n1998.","R.D. Middlebrook and S. Cuk, A General Unified Approach to Modelling\nSwitching Power Stages, IEEE Power Electronics Specialists Conference\nRec., pp. 18-34, 1976.","M. Ahmed, M. Kuisma, K. Tolsa and P. Silventoinen, Standard procedure\nfor modelling the basic three converters (Buck, Boost, and Buck-boost)\nwith PID algorithm applied, Proceedings of the 13th International Symposium\non Electrical Apparatus and Technologies (SIELA), Plovdive, May\n2003.","H. ElFadil, F. Giri and H. Ouadi, Reducing Chattering Phenomenon in\nSliding Mode Control of Buck-Boost Power Converters, IEEE International\nSymposium on Industrial Electronics, 2008.","S.C. Tan, Y.M. Lai and C.K. Tse, A fixed frequency pulse width modulation\nbased quasi sliding mode controller for buck converter, IEEE\nTransactions on Power Electronics, Vol. 20, No. 6, pp. 1379-1392,\nNovember 2005.","S.C. Tan, Y.M. Lai and C.K. Tse, A unified approach to the design of\nPWM based sliding mode voltage controllers for basic DC-DC converters\nin continuous conduction mode, IEEE Transactions on Circuits and\nSystems I, Vol. 53, No. 8, pp.1816-1827, August 2006.","C.K. Tse and K.M. Adams, Quasi-linear analysis and control of DC-DC\nconverters, IEEE Transactions on Power Electronics, Vol. 7 No. 2, pp.\n315-323, April 1992.","X.F. Zhong, G.J. Ye, N.H. Chen and J.L. Jiang, Study on sliding-mode\ncontrol in three-level converters, The 4th International Power Electronics\nand Motion Control Conference, 2004. IPEMC 2004, Vol 3, Issue 2, pp.\n1105 - 1110, August 2004.","V.M. Nguyen and C.Q. Lee, Indirect implementations of sliding-mode\ncontrol law in buck-type converters, Proceedings of the IEEE Applied\nPower Electronics Conference and Exposition (APEC), Vol.1, pp.111-\n115, March 1996.\n[10] A. Kandel and L. Gideon, Fuzzy control systems, CRC Press. New York,\n2000.\n[11] M.K. Passino, Fuzzy control, Addison-Wesley. London, 2000."]}