DC-DC Boost变换器切换规则的设计.doc

  Switching rules design for DC-DC Boost Converters# YANG Yang, XIANG Zhengrong** (School of Automation, Nanjing University of Science and Technology, NanJing 210094) 5 10 15 20 25 30 35 Abstract: A Boost converter modeled as switched affine linear system is mainly discussed in this paper. After building the model, a novel switching rule is proposed, which stabilizes the systems by choosing an active subsystem such that the state trajectory converges to the desired equilibrium point. In addition, a clock delay scheme is designed to solve the phenomenon of sliding modes in the switching strategy and make sure that the working frequency of the system is constant when the system is steady-state. Simulation results for a Boost converter have verified the validity of this method. Keywords: Boost converters; switched affine system; switching strategy; Lyapunov function; clock delay 0 Introduction Due to that the DC-DC converters are operated in a switch mode where an interaction between continuous and discrete dynamics exists, it can be referred to as being hybrid in nature. Most of the DC-DC converters can be modeled as a switched affine linear system. At present, the problem of designing switching strategies for switched dynamic systems has received a great attention in the last decades [1-4]. There are also many references discussed about the switching strategies for switched affine system such as [5-7]. Very recently, some studies for DC-DC converters modeled as switched affine systems have been done. In [8], a hybrid feedback switching rule based on the common Lyapunov function approach is applied in a Buck converter. In [9], a tri-state converter is modeled as switched affine systems and the controller is designed to ensure that the system is always stable in the safe set. The method deals with the class of switched affine systems where the main goal is to attain a set of equilibrium points and the switching rules are designed for DC-DC converters in [10-11]. So