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Wide-bandgap power devices have enabled singlephase totem-pole (TP) power factor correction (PFC) converter designs to be switched at several tens of kilohertz under hardswitching and hundreds of kilohertz under soft-switching. It is straightforward to analyze and compare the volume of boost inductor for TP PFC converters having multileg and multilevel configurations operating under continuous-conduction-mode (CCM) and critical-conduction-mode (CrM) at various switching frequencies; however, the impact of topology and switching frequency selections remains unchallenged for generated differential mode (DM) noise. This article proposes a unified and generalized DM noise estimation method for multileg, and multilevel TP PFC converters operated under both CCM and CrM operation modes. The method has been verified with simulation results obtained from various TP PFC topologies, as well as experimental results obtained from singleleg CCM and 4-Level CCM TP PFC converters. The empirically determined boxed sizes of DM filters have been compared among various TP PFC topologies, and the best switching frequency for each topology has been determined with the integration of boost inductor volume comparison.

In this paper, a new single-stage single-phase isolated AC-DC converter derived from a differential boost AC-DC converter is proposed. This converter eliminates the need to use the bulky electrolytic capacitor from the system and at the same time provides DC charging by employing the AC Power Decoupling waveform control method, effectively addressing the power density and reliability related issues commonly associated with the bulky electrolytic capacitor. As half of the switches of this converter act as synchronous rectifier during half grid cycle they are inherently ZVS Turned On while the remaining switches achieve ZVS Turn On as they act as synchronous rectifier during other half grid cycle. However, all diodes at the secondary side achieve ZCS Turn Off during the entire line cycle. A conventional controller is implemented for output voltage regulation and PFC control whereas a power decoupling controller is added to compensate second harmonic ripple power. Besides, an interleaving technique is applied to provide high-frequency links for transformers' connection while at the same time increasing the power range and effectively reducing the size of the input filter. Finally, the operating principle of the converter is validated through simulation, and the experimental results are provided.

In this paper a single-stage single-phase differential Current-fed isolated AC-DC converter is proposed. This converter eliminates the requirement to use bulky electrolytic capacitor from the system and at the same time provides DC charging by employing the AC Power Decoupling waveform control method. All the switches of the converter achieve ZVS turn on during half line cycle and all diodes achieve ZCS turn off during entire line cycle. A conventional controller is implemented for PFC control and output regulation, whereas a power decoupling controller is added to compensate 2nd harmonic ripple power. In addition, an interleaving technique is applied to increase the power range of the converter and reduce the input inductor size. In the end simulation verification and experimental results are obtained.

This paper proposes an active-snubber-cell and its dual circuit to achieve fully soft-switching operation for PWM DC-DC converters. Main switch of the converter achieves both turn-on and turn-off with zero voltage condition; a switch in the proposed cell achieves zero current turn-on and zero voltage turn-off. The main diode is turned-off with zero current and other semiconductor devices operate under soft-switching condition. No additional voltage and current stresses are imposed by the proposed cell. The proposed active-snubber-cell can be applied in a range of PWM DC-DC converters; the guidelines for implementing the proposed cell will be presented. Easy implementation for an interleaved converter makes the proposed cell is suitable for high power applications. The presented operating principle and analysis is verified using a 100 kHz and 1kW prototype of the proposed cell implemented on a boost converter. As a result, the peak efficiency of 98% is achieved.

Sandwip is an island along the south eastern coast of Bangladesh. Sandwip is a sub-division of Chittagong district located at 22.490513°N 91.421185°E. It is situated at the estuary of the Meghna River on the Bay of Bengal and separated from the Chittagong coast by the Sandwip channel. It has a population of nearly 400,000. There are 15 unions in Sandwip. There are also as many as fifteen different wards, 62 mahallas and 34 villages on the Sandwip Island. The entire island is 50 kilometres long and 5-15 kilometres wide with an area of 762.42 km2. Sandwip has a very large potential for tidal power generation with a tidal variation of 5-6 m. A flood control barrage exists around the entire island and this contains 28 sluice gates. Considering each sluice gate is capable for one turbine and one generator, a very large amount of power can be generated from Sandwip. The main objective of this paper is to utilize these sluice gates to find the potentiality of tidal power in Sandwip by using one turbine for both one way & two way power generation technology & support the results by proper mathematical model. The mathematical regime proposed in this paper is very simple and effective and only associated with two variables, surface area of the basin and tidal variations. Based on this methodology the outputs are 0.028AR2 and 0.056AR2 for one way and two way power generation systems respectively. Because of the massive size of the oceans and the prediction accuracy of tidal, it is more preferable than any other renewable sources. While the discussion in this paper focuses mainly on Sandwip, the messages are relevant for other areas that has the potential to engage in Tidal Power.