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In this paper, a detailed modelling and analysis of a switched inductor (SI)-based improved single-ended primary inductor converter (SEPIC) has been presented. To increase the gain of conventional SEPIC converter, input and output side inductors are replaced with SI structures. Design and stability analysis for continuous conduction mode operation of the proposed SI-SEPIC converter has also been presented in this paper. State space averaging technique is used to model the converter and carry out the stability analysis. Performance and stability analysis of closed loop configuration is predicted by observing the open loop behaviour using Nyquist diagram and Nichols chart. System was found to stable and critically damped. [ABSTRACT FROM AUTHOR]

This paper postulates a tunable active inductor-based voltage controlled oscillator for IEEE 802.11 a/b/g/n/ac applications in 90 nm CMOS process. In the designed VCO, the modified topology of the active inductor which uses regulated cascode is implemented along with tuning competency. The layout-based simulation has been performed considering parasitic resistances and capacitances. The designed VCO yields an oscillation frequency ranging from 1.93 GHz to 5.97 GHz having tuning scope of 102%, where the tuning voltages is varied from 0 V to 0.8 V. The power consumption varies from 0.97 mW to 3.32 mW, and the VCO provides a differential output power of 3.29 dBm to −4.76 dBm. The phase noise varies from −78.52 dBc/Hz to −70.45 dBc/Hz, and the figure of merit (FOM) has a value of −143.63 dBc/Hz @ 5.09 GHz frequency. The designed VCO has been passed through process corner analysis, Monte Carlo analysis, stability analysis and temperature swept analysis to evaluate its compatibility. Furthermore, the elimination of MOS varactor has reduced overall silicon area consumption (39.73 × 25.3 \mum). Finally, the designed VCO's performance parameters have been compared with referred designs where it is illustrated that the designed VCO outperforms the others in most cases along with a good scope for implementing both 2.4 GHz and 5 GHz frequency that is, IEEE 802.11a/b/g/n/ac applications. [ABSTRACT FROM AUTHOR]

The growth of the power industry is gaining greater momentum as the usage of the non-conventional energy sources that include fuel, solar, and wind energies, increases. Wind energy conversion systems (WECSs) are gaining more popularity and are expected to be able to control the power at the output. This paper describes the current control (CC), non-linear carrier charge control (NLCCC), and fuzzy logic control (FLC) applied to the single-ended primary inductor converter (SEPIC)-based WECS. The current controller has an inherent overcurrent protection with better line noise rejection. The pulses for the switch of the SEPIC are obtained by comparing the current flowing through it with the virtual current reference. FLC is also investigated for the micro-wind energy conversion system (μWECS), since it improves the damping characteristics of WECS over a wide range of operating points. This cannot attain the unity power factor rectification. In this paper, NLCCC is proposed for high-power factor rectifier-based SEPIC in continuous conduction mode (CCM) for μWECS. The proposed converter provides an output voltage with low input current ripple due to the presence of the inductor at the input side. By comparing the signal proportional to the integral of switch current with a periodic non-linear carrier wave, the duty ratio of the converter switch is determined for the NLCC controller. By selecting the shape of the periodic non-linear carrier wave the input-line current can be made to follow the input-line voltage. This work employs a parabolic carrier waveform generator. The output voltage is regulated for changes in the wind speed. The results obtained prove the effectiveness of the NLCC controller in improving the power factor. [ABSTRACT FROM AUTHOR]

High Brightness Light Emitting Diodes (HBLEDs) replace conventional lamps due to energy savings. LC3 parallel resonance principle is used to reduce the total harmonic distortion (THD) for passive LED drivers. The Valley fill concept is applied to reduce the output voltage ripple of LED driver. This paper presents the design and analysis of an integrated LC3-Valley fill passive LED driver suitable for HBLEDs. Valley fill approach is added with LC3 characteristics to further enhance the performance of the LC3-based LED driver. The proposed LED driver achieves high input power factor, low THD with reduced ripple in the output voltage. The integrated passive LED driver consists of inductors, capacitors and diodes only without using any semiconductor-based switching devices and control circuitry. A 70 W driver circuit using single-phase, 230 V, 50 Hz, ac supply is implemented to verify the theoretical analysis. Performance comparison of the integrated LC3-Valley fill passive LED driver is carried out with the existing passive LED driver topologies. An energy efficiency exceeding 95% is obtained. [ABSTRACT FROM AUTHOR]

This paper proposes a three-phase interleaved buck converter which is composed of three identical paralleled buck converters. The proposed solution has three shunt inductors connected between each other of three basic buck conversion units. With the help of the shunt inductors, the MOSFET parasitic capacitances will resonate to achieve zero-voltage-switching. Furthermore, the decreasing rate of the current through the free-wheeling diodes is limited, and therefore, their reverse-recovery losses can be minimised. The active power switches are controlled by interleaved pulse-width modulation signals to reduce the input and output current ripples. Therefore, the filtering capacitances on the input and output sides can be reduced. The power efficiency is measured to be as high as 98% in experiment with a prototype circuit. [ABSTRACT FROM PUBLISHER]

This paper proposed a novel three-phase single-capacitor Z-source inverter (SC-ZSI) topology and a one-cycle control (OCC) method for three-phase SC-ZSI. It uses a unique single-capacitor Z-source impedance network for boosting its output voltage. Comparing with SL-ZSI and SL-qZSI, the proposed SC-ZSI reduces capacitor voltage stress and inductor current stress with the same boost factor. Comparing with L-ZSI, SL-ZSI, and SL-qZSI, the proposed SC-ZSI can provide a high boost factor with a small shoot-through duty ratio. A novel OCC method for three-phase SC-ZSI with unity-power-factor correction is proposed. The method is composed of two parts and described in detail. One part is the OCC for DC link voltage, and the other part is three-phase AC voltage OCC based on SVPWM. The simulation and experimental results show that the topology of SC-ZSI is correct and the OCC for SC-ZSI is effective. [ABSTRACT FROM AUTHOR]

Face to the growing number of applications using DC–DC power converters, the improvement of their reliability is subject to an increasing number of studies. Especially in safety critical applications, designing fault-tolerant converters is becoming mandatory. In this paper, a switch fault-tolerant DC–DC converter is studied. First, some of the fastest Fault Detection Algorithms (FDAs) are recalled. Then, a fast switch FDA is proposed which can detect both types of failures; open circuit fault as well as short circuit fault can be detected in less than one switching period. Second, a fault-tolerant converter which can be reconfigured under those types of fault is introduced. Hardware-In-the-Loop (HIL) results and experimental validations are given to verify the validity of the proposed switch fault-tolerant approach in the case of a single switch DC–DC boost converter with one redundant switch. [ABSTRACT FROM AUTHOR]

A high voltage step-up nonisolated DC–DC converter based on coupled inductors suitable to photovoltaic (PV) systems applications is proposed in this paper. Considering that numerous approaches exist to extend the voltage conversion ratio of DC–DC converters that do not use transformers, a detailed comparison is also presented among the proposed converter and other popular topologies such as the conventional boost converter and the quadratic boost converter. The qualitative analysis of the coupled-inductor-based topology is developed so that a design procedure can be obtained, from which an experimental prototype is implemented to validate the theoretical assumptions. [ABSTRACT FROM PUBLISHER]