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This article proposes a novel single-phase bridgeless Cuk-derived power factor corrected (PFC) converter with reduced component count for on-board EV charging application. The unique feature of this proposal is to design and operate the output inductor of the converter in discontinuous current mode for the complete power range to attain PFC naturally at ac mains, thereby not requiring the input voltage and input current sensing, which reduces the converter cost, and improves the power density as well as converter robustness to high-frequency noise. The converter control is very simple in operation and easy in implementation with only a single sensor-based voltage control loop. The semiconductor components voltage stress of the proposed power converter is lower when compared to the traditional Cuk converter. The simulation results from PSIM 11 and experimental results are given by testing a proof-of-concept hardware laboratory prototype to demonstrate the high performance of PFC operation of the proposed converter. [ABSTRACT FROM AUTHOR]

Due to the pulsating power at the inverter output terminals, the passive storage elements of the boost stage of the current-fed switched inverter (CFSI) contain a power frequency harmonic component (100 Hz), apart from dc and switching frequency components. In prior designs, the second harmonic component is suppressed by increasing the size of the input filter inductor and capacitor or by using additional circuits. This paper presents a complete characterization of a control-based approach to suppress the power frequency harmonic component in the input inductor current of a CFSI. It also presents a comprehensive characterization of the harmonic power redistribution. Using the proposed approach, it is demonstrated that the inductor value of a CFSI is reduced by 61% for the same peak-to-peak ripple. This leads to an improvement in the conversion ratio, efficiency, and power density of the overall converter. A SiC MOSFET-based CFSI with 75-kHz switching frequency is used to verify the proposed design philosophy. [ABSTRACT FROM AUTHOR]

Multioutput converters with single input source are currently studied as an alternative to conventional dc–dc topologies in order to improve power density in low-power multiload applications. This paper reviews three different ways in which a boost topology can be customized to supply multiple outputs. The first way uses a charge-sharing approach using individual switches to distribute inductor energy to different capacitors. The second method of creating a multiport converter (MPC) combines two converters with similar front end to generate two outputs using only one controlled switch. Using this method, a boost converter can be combined with single–ended primary–inductor converter (SEPIC), Cuk, and current source converter topologies. The third method uses time multiplexing of switches to produce two regulated ports and is referred to as switched-boost action. This method uses relatively less number of switches and allows regulation and control of all the outputs. Practical utility of switched-boost action based MPC is reported in this paper. This switched-boost MPC is applied to a renewable power converter system to interface a solar panel, a battery, and home loads to produce a 12-V and a 48-V bus. The 12-V bus is interfaced to battery and capable of optimally charging the battery in constant current–constant voltage (CC-CV) mode. The converter is demonstrated to operate with solar panel as it supplies a 12-V battery and a 48-V load bus. When the solar power is not available, the converter automatically goes into a mode in which the 12-V battery supplies the loads on the 48-V bus. [ABSTRACT FROM AUTHOR]

Capacitively coupled power transfer (CCPT) uses electrostatic mechanism to deliver power from a stationary transmitter to a mobile receiver. The authors study various aspects of this technology including physical limitations that are encountered to increase power transfer. They characterise the impact of input voltage, dielectric area, and permittivity of the dielectric material in realisation of CCPT system. It is observed that the peak voltage and VA ratings of the capacitors are affected by the choice of the aforementioned parameters. Air as a dielectric medium leads to low power density. A high permittivity material instead of air dielectric can be used to improve power density. This strategy will make the CCPT technology non-contactless, because a physical contact exists between the transmitter and receiver. However, this contact is different from an ohmic contact. A high power density CCPT system is realised using ceramic dielectric surfaces. Issues encountered in system realization are discussed including automatic resonant frequency tracking. Detailed mathematical models under resonance and off-resonance operation are proposed. The models are validated using simulations and experimental results. A low cost multilayer ceramic capacitor (MLCC) based high power-density transfer surface is realised. Results show that 35 W can be easily transferred using a set of 12 mm2 capacitive surfaces and 32 V source. [ABSTRACT FROM AUTHOR]