Polynomial Curve Slope Compensation for Peak-Current-Mode-Controlled Power Converters

Abstract

Linear Ramp Slope Compensation (LRC) and Quadratic Slope Compensation (QSC) are commonly implemented in peak current mode controlled DC-DC converters in order to minimize subharmonic and chaotic oscillations. Both compensating schemes rely on the linearized state-space averaged model (LSSA) of the converter. LSSA ignores the impact that switching actions have on the stability of converters. In order to include switching events, the nonlinear analysis method based on Monodromy matrix was introduced to describe a complete-cycle stability. Analyses on analogue controlled DC-DC converters applying this method show that system stability is strongly dependent on the change of the derivative of the slope at the time of switching instant. However, in a mixed-signal controlled system, the digitalization effect contributes differently to system stability. This paper shows a full complete-cycle stability analysis using this nonlinear analysis method, which is applied to a mixed-signal controlled converter. Through this analysis, a generalized equation is derived that reveals for the first time the real boundary stability limits, for LRC and QSC. Furthermore, this generalized equation allows the design of a new compensating scheme which is able to increases system stability. The proposed scheme is called Polynomial Curve Slope Compensation (PCSC) and it is demonstrated that PCSC increases the stable margin by 30% compared to LRC and 20% to QSC. This outcome is proved experimentally by using an interleaved DC-DC converter that is built for this work.

Design of an Advanced Programmable Current-Source Gate Driver for Dynamic Control of SiC Device

“…SiC is widely recognized as one of the next generation power semiconductors due to its superior feature for high voltage, high frequency, high power density and high temperature applications [1]- [4]. However, the material advantages of SiC devices have not been fully exploited, and optimized gate driver circuit is required for SiC device to achieve better dynamic performance [5].…”

Design and control of a bidirectional wireless charging system using GaN devices

“…Wireless power transfer (WPT) technology has been developing rapidly in industry which is able to provide a reliable, flexible and cost-efficient power delivery solution. Particularly, in many environments that are hindered by the wired connection, this technique shows huge potential such as home appliances, medical applications and the most concerned fieldelectric vehicles [1]- [3]. The most mature technique used in WPT is electromagnetic induction, there are numerous literatures focused on this technique handling with how to improve transmit efficiency and specially looking into the contribution based on the study of different topologies [4] - [7].…”

Slope Compensation Design for a Peak Current-Mode Controlled Boost-Flyback Converter

“…The stability of the Period-1 orbit is also analyzed by presenting the Poincaré map as a monodromy matrix such that by analyzing eigenvalues of the monodromy matrix (Floquet multipliers), it is possible to determine the stability of a Period-1 orbit [13]. Several studies also combine bifurcations and monodromy matrix analyses [6,14].…”

“…Once slope compensation is designed, system behaviors can be improved by changing, retuning or controlling slope compensation. To improve the behavior of the controlled system, a polynomial curve slope compensation scheme was proposed [14]. This slope secures better results than a traditional linear ramp slope compensation scheme, though its practical implementation is less straightforward.…”

“…In this paper, an analytical expression for determining the initial value of the slope compensation of a BF converter via peak current-mode control is determined. Unlike modern means of improving the range of stability of the compensation ramp [10,14,49,50], the proposed technique is less complex and therefore easier to implement and allows the precise calculation of the compensation ramp, which guarantees correct operation and prevents unwanted behaviors from manifesting. A complete analysis of stability and transitions to chaos for a peak-current mode-controlled BF converter is reported in [51], and the coexistence of Period-1, Period-2 and chaotic orbits with varying coupling coefficients has been proven via bifurcation analysis [52].…”