Assessment of an Average Controller for a DC/DC Converter via Either a PWM or a Sigma-Delta-Modulator

Abstract

Sliding mode control is a discontinuous control technique that is, by its nature, appropriate for controlling variable structure systems, such as the switch regulated systems employed in power electronics. However, when designing control laws based on the average models of these systems a modulator is necessary for their experimental implementation. Among the most widely used modulators in power electronics are the pulse width modulation (PWM) and, more recently, the sigma-delta-modulator (Σ-Δ-modulator). Based on the importance of achieving an appropriate implementation of average control laws and the relevance of the trajectory tracking task in DC/DC power converters, for the first time, this research presents the assessment of the experimental results obtained when one of these controllers is implemented through either a PWM or aΣ-Δ-modulator to perform such a task. A comparative assessment based on the integral square error (ISE) index shows that, at frequencies with similar efficiency, theΣ-Δ-modulator provides a better tracking performance for the DC/DC Buck converter. In this paper, an average control based on differential flatness was used to perform the experiments. It is worth mentioning that a different trajectory tracking controller could have been selected for this research.

PI-Type Controllers and Σ–Δ Modulation for Saturated DC-DC Buck Power Converters

“…In order to detect more details in the performance, the experimental data have been collected and shown in Figure 8 Figure 8 shows that the output voltage is noisier when using the PWM technique than when implementing the Σ-∆ modulation. This evidence demonstrates that the Σ-∆ modulator is more suitable than the PWM in applications where a lower ripple and a smoother output voltage are required [15].…”

“…Furthermore, battery chargers, microprocessors, and motherboards, extensively use DC-DC converters. Electronic devices that need constant voltage to safely and correctly function are supplied with battery packages (for details, refer to the following works and the references therein [15], [16], [17], [18]). In this situation, buck converters are appropriate since the output voltage is regulated to a lower voltage than the supplied by the batteries.…”

Output Series-Parallel Connection of Passivity-Based Controlled DC–DC Converters: Generalization of Asymptotic Stability

“…3 shows the schematic diagram of the feedback control scheme for the PBC of dc-dc converters. The actual dcdc converter is regulated by a discrete switching variable, hence the duty ratio is processed through analog-to-digital conversion, typically pulse-width modulation (PWM) or deltasigma modulation [22], [31]. A hard limiter is implemented to guarantee the duty ratio to be in the closed interval [0,1].…”

Assessment of an Average Tracking Controller that Considers all the Subsystems Involved in a WMR: Implementation via PWM or Sigma-Delta Modulation

“…No obstante, se observó que utilizando el modulador Σ − Δ se consigue un mejor desempeño en la implementación conmutada del controlador. Esto es debido a que, de forma natural, el modulador Σ − Δ reduce el ruido presente en las señales, i.e., actúa como filtro [40], [41]. Se verificó también que el controlador es robusto cuando se consideran variaciones abruptas y simultáneas en algunos parámetros del sistema.…”