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Several studies have proved that the use of Ferrite Core (FC) power inductors operating in moderate saturation allows volume and weight of Switch-Mode Power Supplies (SMPSs) to be reduced. Thus, a reliable analysis of non-linear FC inductors operating in moderate saturation is fundamental for the design of high-power-density SMPSs. This paper suggests the application of a Pulse Compression procedure for the Hammerstein model identification of the inductance versus current characteristic of FC inductors. The proposed approach allows a reliable model of FC inductors to be obtained up to moderate saturation non-linearity. Several simulations in cases of practical interest are presented, with comparisons to an established literature behavioral model and its Taylor and Padé numerical approximations. [ABSTRACT FROM AUTHOR]

This paper investigates the Sustainable Saturation Operation (SSO) of Ferrite Core Power Inductors (FCPIs) in Switch Mode Power Supplies (SMPSs). A ferrite inductor is considered in SSO if its current ripple, power losses and temperature rise are acceptable and reliable for both the device and the SMPS, despite the inductance drop determined by the core saturation. An algorithm is discussed, which identifies SSO-compliant FCPIs with minimum size and volume, given the SMPS specifications about the allowed power losses, temperature rise and peak-to-peak current ripple of the inductor. The experimental results relevant to a 465 kHz/3.3 V/1.5 A buck converter show that SSO-compliant inductors allow to increase the SMPS power density, while preserving the overall converter efficiency. Despite the proposed low power application, the findings relevant to the utilization of power inductors in partial saturation have general conceptual valence and similar investigations can be prospectively re-assessed for few kW output power DC/DC converters. [ABSTRACT FROM AUTHOR]

This paper discusses a novel method for the analysis of MOSFET commutations and the investigation of related losses and spike current issues in the switching power converter (SPC) design. The synchronous rectification switching cell (SRSC) configuration is considered for the investigation, which is used in the high-frequency high-efficiency (H^2EF) SPC design. The proposed method is aimed at providing an effective tool for quick feasibility investigations and comparative evaluations among design solutions using different MOSFET combinations for the design of H^2EF SPCs. The method allows us to use nonlinear models of interelectrode MOSFET capacitances and adopts a novel numerical technique specifically developed to solve the SRSC model ensuring robust and fast simulations. Capacitive pulsating currents circulating through the MOSFETs and the SPC during commutations can be analyzed in detail by using the proposed method. Different examples are discussed to show how MOSFETs characteristics and operating conditions may affect switching losses, because of the pulsing currents circulation through the SPC. [ABSTRACT FROM AUTHOR]

• Application of saturated inductors in buck converters would significantly reduce the volume and weight. • The current ripple in DC-DC buck converters is influenced by the saturation of the inductor. • The current waveform in DC-DC buck converters is computed through a successive approximation method. In this paper we propose a model for the analysis of the current waveform in ferrite power inductors subjected to large-signal square-wave voltage, a typical regime of present-day switch-mode power supplies. This problem is characterized by the non-linear response of the inductor across a wide range of current values, up to the limit of inductor saturation. Consequently, non-linear differential equations must be adopted in the description of the circuit. In this paper, we solve the equations of the circuit through an effective iterative method, by which the current waveform is computed through successive approximations. These results are eventually verified by comparison with experiments performed on a commercial buck-type converter. [ABSTRACT FROM AUTHOR]