Analysis of a bidirectional coupled-inductor Cuk converter operating in sliding mode

Abstract

Analytic models for a bidirectional coupled-inductoŕ Cuk converter operating in sliding mode are described. Using a linear combination of the converter four state variable errors as a general switching surface, the expression for the equivalent control is derived and the coordinates of the equilibrium point are obtained. Particular cases of the general switching surface are subsequently analyzed in detail: 1) surfaces for ideal line regulation, 2) surfaces for ideal load regulation, and 3) surfaces for hysteretic current control. Simulation results verifying the analytical predictions are presented.

An evaluation of the practicality of sliding mode controllers in DC-DC converters and their general design issues

“…This spurred a series of related works on theĆuk converter [14]- [19]. In particular, Mahdavi et al [17] developed the first PWM based SM controlledĆuk converter in 1996.…”

Indirect Sliding Mode Control of Power Converters Via Double Integral Sliding Surface

“…derive the stability condition [18], [28]. This is to first derive the ideal sliding dynamics of the system, and then doing an stability analysis on its equilibrium point.…”

“…To ensure the existence of SM operation, the local reachability condition 0 must be satisfied. This can be expressed as (20) Case 1-Buck Converter: For the DISM voltage controlled buck converter, the existence condition for steady-state operations (equilibrium point) [8], [18], [34], can be derived by substituting (8) eration of the system's dynamics (10) as (21), shown at the bottom of the page, where denotes the minimum input voltage; denotes the expected steady-state output, i.e., approximately the desired reference voltage ; and are, respectively, the maximum and minimum capacitor currents at full-load condition; and are respectively the maximum and minimum steady-state voltage errors, which in this case are basically the inverse functions of the output voltage ripples; and and are respectively the maximum and minimum integrals of the steady-state voltage error, which is the time integral of the inverse functions of the output voltage ripples with a negligible dc shift. All these parameters can be calculated from the design specification of the converter.…”

Design of Pulsewidth-Modulation Based Sliding Mode Controllers for Power Converters in Discontinuous Conduction Mode

“…Here, it is taken into account the complete ranges of operating conditions (minimum and maximum input voltages, i.e., v i(min) and v i(max) , and minimum and maximum load resistances, i.e., r L(min) and r L(max) ). Additionally, the state variables i C and v o are substituted with their expected steady-state parameters, i.e., i C(SS) and v o(SS) , to assure the compliance of the existence condition at least in the small region of the origin [7], [8]. The selection of sliding coefficients must comply the respective inequalities.…”