Stability Analysis of a Controller/Observer for Input–Constrained DC–DC Boost Power Converters

Abstract

In this paper, a new stability analysis of a known controller/observer for DC-DC boost converters is presented. The new analysis considers the overall closed-loop system, which includes the dynamics of the observation error as well as the dynamics of current and voltage error. This analysis relies in the stability theory of cascaded time-varying systems. In addition, two real-time experiments are shown, illustrating the robustness of the controller/observer. IntroductionThe interesting problem about DC-DC boost power converters in the nonlinear control research is the possibility of improving performance in one way or another, compared with the simple linear compensators commonly used in this type of devices. DC-DC boost power converters can be described as a bilinear second order nonminimum phase system with saturated input [1]. It is noteworthy that the non-minimum phase property is related to the behavior of the zero dynamics when the output is the voltage [2]. In order to provide a degree of robustness to compensate uncertainties in the load, supply voltage and unmodeled disturbances, many control algorithms have been devised to achieve voltage output regulation.Many methodologies have been proposed to control the output voltage of DC-DC boost converters. For example, Alvarez et al. in [3] analyzed a two-loop scheme consisting in an inner current loop control plus an outer voltage loop control. The research in [4] addressed the boost converter control by using the linear matrix inequality (LMI) approach. The methodology introduced in [5] dealt with a fast convergence controller having the cost of knowing all the boost parameters and two states available for feedback.Works considering saturation of duty cycle in control input for buck converters can be found in [6] and

Experimental evaluations of voltage regulators for a saturated boost DC-to-DC power converter

“…is given in Karagiannis et al (2003); however, an alternative proof of asymptotic stability, which is based on the known results of cascaded nonlinear systems, is reported in Guzman-Guemez and Moreno-Valenzuela (2013a).…”

“…In the paper by Guzman-Guemez and Moreno-Valenzuela (2013b) the state-space origin of the unperturbed system (45) is proven to be globally asymptotically stable while in the work in Guzman-Guemez and Moreno-Valenzuela (2013a) the global asymptotic stability of the system (44) is shown. An outline of the above steps to show the stability of the cascaded system of equations (43) and (44) is given in the Appendix and is based on the proof of Theorem 1 in Loría and De León Morales (2003).…”

Analysis and Design of a Controller for an Input-Saturated DC–DC Buck Power Converter

“…In [30], the control of a boost power converter by using only measurements of the output voltage and estimating the supply voltage was addressed. By using the theory of stability for cascade systems, the controller-observer given by [30] was revisited in [31] and [32]. In [33], an adaptive neural network controller was presented.…”