Soft-Switching Full-Bridge Converter with Multiple-Input Sources for DC Distribution Applications

Abstract

Due to the advantages of power supply systems using the DC distribution method, such as a conversion efficiency increase of about 5–10%, a cost reduction of about 15–20%, etc., AC power distribution systems will be replaced by DC power distribution systems in the future. This paper adopts different converters to generate DC distribution system: DC/DC converter with PV arrays, power factor correction with utility line and full-bridge converter with multiple input sources. With this approach, the proposed full-bridge converter with soft-switching features for generating a desired voltage level in order to transfer energy to the proposed DC distribution system. In addition, the proposed soft-switching full-bridge converter is used to generate the DC voltage and is applied to balance power between the PV arrays and the utility line. Due to soft-switching features, the proposed full-bridge converter can be operated with zero-voltage switching (ZVS) at the turn-on transition to increase conversion efficiency. Finally, a prototype of the proposed full-bridge converter under an input voltage of DC 48 V, an output voltage of 24 V, a maximum output current of 21 A and a maximum output power of 500 W was implemented to prove its feasibility. From experimental results, it can be found that its maximum conversion efficiency is 92% under 50% of full-load conditions. It was shown to be suitable for DC distribution applications.

Soft-Switching Full-Bridge DC-DC Converter with Energy Recovery Capacitor Snubber

“…Moreover, the transistor T 5 cancels the circulating current during a free-wheeling interval of the converter, and its duty cycle controls the output power of the converter. Some designs, e.g., [8,25] do not try to eliminate the circulating current and rely on the low conduction losses of modern semiconductor devices. However, this is only possible for low-voltage MOSFETs, as the converter in [25] is supplied from 48 V and its output power is 500 W. It is common to disconnect the output rectifier and thus cancel the circulating current for higher power levels [5,17].…”

Ferrites and Nanocrystalline Alloys Applied to DC–DC Converters for Renewable Energies

“…In this situation, the MFT with nanocrystalline core shows higher power density and 7.8 times less weight. Nanocrystalline alloys cores are designed for 0.9 T flux density and silicon steel for 0.1 T. Although the cost per cm 3 of the nanocrystalline material (87.62 USD/kg) is higher than silicon steel (11.71 USD/kg), the final total cost of both MFTs is similar because of smaller size of the MFT obtained with nanocrystalline alloys, USD 395 for the silicon steel MFT, and USD 375 for the nanocrystalline one.…”

“…Medium frequency transformer, MFTs, are fundamental to the development of newly advanced DC-DC converters [1][2][3][4]. These converters are becoming key player in building Smart-Grid environments [5], in interfacing renewable energy to medium power grids [6][7][8][9], in constructing the emerging solid-state transformer technology [5,10], and in electric vehicles, as shown in Figure 1.…”

Maximum Power Point Tracking Techniques for Photovoltaic Panel: A Review and Experimental Applications

“…where x t , h t , y t , are, respectively, the input vector, the hidden layer vector, and the output vector; W, U, and b, are parameter matrices and vector; σ h and σ y are activation functions, respectively, given in Equations ( 19) and (20).…”

“…The first mentioned refers to an electrical limit (such as a transformer) amid the inputs and outputs which allows the usage for high voltages. Examples of these types are flyback, forward, resonant, push-pull and bridge [16][17][18][19][20]. In the non-isolated, the configuration indicates that the mentioned barrier is vanished and therefore, the efficiency tends to be higher since the number of components is lower [21].…”