New Semiquadratic High Step-Up DC/DC Converter for Renewable Energy Applications

Abstract

In this paper, a new Semi-Quadratic High Step-Up Coupled-Inductor DC/DC Converter (SQHSUCI) with continuous input current and low voltage stress on semiconductor components is presented. The proposed structure employs a coupled-inductor (CI) and two power switches with simultaneous operation to achieve an extremely high voltage conversion ratio in a semiquadratic form. The voltage stress across the main power switch is clamped by two regenerative clamp capacitors. Here, the switching losses of both MOSFETs have been reduced by applying quasi-resonance operation of the circuit created by the leakage inductance of the CI along with the balancing and clamp capacitors. Therefore, by considering the high gain conversion ratio along with low voltage stress on components, the magnetic and semiconductors losses of the SQHSUCI are reduced significantly. Also, the energy stored in the leakage inductance of CI is recycled to the output capacitor. These features make the proposed SQHSUCI more suitable for industrial applications. The operation principle, steady-state and also comparisons with other related converters in Continuous Conduction Mode (CCM) are discussed in detail. Finally, experimental results of a prototype with 20 V input and 200 W-200 V output at 50 kHz switching frequency, verify the theoretical advantages of the proposed strategy.

A new high‐efficiency interleaved step‐up converter with zero‐voltage switching, zero‐current switching, and common‐ground features for stand‐alone electric vehicle charging stations

“…Figure 9A,B depicts each term in (34) and (36). Figure 9B confirms that the output voltage gain is less sensitive to the duty cycle (D) in comparison with the turns ratio of coupled inductors.…”

“…However, of those topologies, interleaved step-up converters are more compatible than simple ones due to low input current ripple. 36 This paper proposes an interleaved step-up dc-dc converter with new active clamp circuit that provides ZVS and ZCS operations for the converter. The interleaved operation is useful for high-power high-efficiency stand-alone EV charging station.…”

A New Hybrid Ćuk DC-DC Converter with Coupled Inductors

“…For n = 2, we have √ = 0.365, for n = 3, √ = 0.33, which means that the proposed converter from Figure 2 has a both step-up and step-down nature. However, compared to the Buck-Boost or the Ćuk converter the converter starts to step-up as a considerably lower duty cycle, in the example provided around 0.33 compared to the From (6), the duty cycle can be expressed in terms of static conversion ratio as:…”

“…With D min = 0.6, because the minimum static conversion ratio corresponds to D min , the necessary turns ratio results from Equations (6) and (34):…”

“…Dc-dc converters are used in a large variety of applications: unidirectional and bidirectional chargers in automotive, renewable energies in photovoltaic cells for example, dc grids, cellphones, computers, laptops and so forth. These power circuits should be able to step-up [1][2][3][4][5][6][7][8][9], step-down [10][11][12][13] or step-up/step-down [14][15][16][17][18][19][20][21] the voltage from the input. The polarity of the output voltage can be the same [1][2][3][4][6][7][8] or reverse [5,[22][23][24][25][26][27][28][29] compared to that of the input voltage.…”