Inductor

About: Inductor is a research topic. Over the lifetime, 52565 publications have been published within this topic receiving 484068 citations. The topic is also known as: passive two terminal.

Design and Analysis of a High-Efficiency DC–DC Converter With Soft Switching Capability for Renewable Energy Applications Requiring High Voltage Gain

Abstract: Renewable sources like solar photovoltaic (PV) and fuel cell stack are preferred to be operated at low voltages. For applications such as grid-tied systems, this necessitates high voltage boosting resulting in efficiency reduction. To handle this issue, this paper proposes a novel high voltage gain, high-efficiency dc–dc converter based on coupled inductor, intermediate capacitor, and leakage energy recovery scheme. The input energy acquired from the source is first stored in the magnetic field of coupled inductor and intermediate capacitor in a lossless manner. In subsequent stages, it is passed on to the output section for load consumption. A passive clamp network around the primary inductor ensures the recovery of energy trapped in the leakage inductance, leading to drastic improvement in the voltage gain and efficiency of the system. Exorbitant duty cycle values are not required for high voltage gain, which prevents problems such as diode reverse recovery. Presence of a passive clamp network causes reduced voltage stress on the switch. This enables the use of low voltage rating switch (with low “ on -state” resistance), improving the overall efficiency of the system. Analytical details of the proposed converter and its hardware results are included.

Zero-Voltage-Switching DC–DC Converters With Synchronous Rectifiers

Abstract: Active resonant tank (ART) cells are proposed in this paper to achieve zero-voltage-switching (ZVS) and eliminate body-diode conduction in DC-DC converters with synchronous rectifiers (SRs). In low-output-voltage DC-DC converters, SRs are widely utilized to reduce rectifier conduction loss and improve converter efficiency. However, during switches' transition, SRs' parasitic body diodes unavoidably carry load current, which decreases conversion efficiency because voltage drop across body diodes is much higher than that across SRs. Moreover, body diodes' reverse recovery leads to increased switching losses and electromagnetic interference. With the proposed cells of an ART, the body diode conduction of the SR is eliminated during the switching transition from a SR to an active switch, and thus body diode reverse-recovery-related switching and ringing losses are saved. An ART cell consists of a LC resonant tank and an auxiliary switch. A resonant tank cell is charged in a resonant manner and energy is stored in the capacitor of the tank. Prior to a switching transition from a SR to an active switch, the energy stored in the tank capacitor is released and converted to inductor current, which forces the SR current changes direction to avoid conduction of the body diode and related reverse recovery when the SR turns off. Moreover, at the help of energy released from the ART, the active switch's junction capacitance is discharged, which allows the active switch turns on at ZVS. Since energy commutation occurs only during switching transition, conduction loss in the ART cell is limited. Moreover, the auxiliary switch turns off at ZVS and the SR operates at ZVS. The concept of ART cells is generally introduced and detailed analysis is presented based on a synchronous buck converter. Experimental results show the proposed ART cell improves conversion efficiency due to the reduced switching loss, body diodes' conduction, and reverse-recovery losses.

Resonant Contactless Energy Transfer With Improved Efficiency

Abstract: This paper describes the theoretical and experimental results achieved in optimizing the application of the series loaded series resonant converter for contactless energy transfer. The main goal of this work is to define the power stage operation mode that guarantees the highest possible efficiency. The results suggest a method to select the physical parameters (operation frequency, characteristic impedance, transformer ratio, etc.) to achieve that efficiency improvement. The research clarifies also the effects of the physical separation between both halves of the ferromagnetic core on the characteristics of the transformer. It is shown that for practical values of the separation distance, the leakage inductance, being part of the resonant inductor, remains almost unchanged. Nevertheless, the current distribution between the primary and the secondary windings changes significantly due to the large variation of the magnetizing inductance. An approximation in the circuit analysis permits to obtain more rapidly the changing values of the converter parameters. The analysis results in a set of equations which solutions are presented graphically. The graphics show a shift of the best efficiency operation zone, compared to the converter with an ideally coupled transformer. Experimental results are presented confirming that expected tendency.

Single-inductor multiple-output switching converters

Abstract: A family of single-inductor multiple-output switching power converters is presented. They can be classified into same-type, bipolar and mixed-type converters. Synchronous rectification and control loop design are discussed, and experimental and simulation results of representative converters are presented to verify the functionality of these converters.

Optimization of inductor circuits via geometric programming

Abstract: We present an efficient method for optimal design and synthesis of CMOS inductors for use in RF circuits. This method uses the the physical dimensions of the inductor as the design parameters and handles a variety of specifications including fixed value of inductance, minimum self-resonant frequency, minimum quality factor, etc. Geometric constraints that can be handled include maximum and minimum values for every design parameter and a limit on total area. Our method is based on formulating the design problem as a special type of optimization problem called geometric programming, for which powerful efficient interior-point methods have recently been developed. This allows us to solve the inductor synthesis problem globally and extremely efficiently. Also, we can rapidly compute globally optimal trade-off curves between competing objectives such as quality factor and total inductor area. We have fabricated a number of inductors designed by the method, and found good agreement between the experimental data and the specifications predicted by our method.