Kind of high step‐up dc/dc converter using a novel voltage multiplier cell

Abstract

This study proposes a kind of high step-up dc/dc converter with a novel voltage multiplier cell (VMC). The proposed VMC sharply reduces voltage stress on switches and diodes. Therefore, the conversion efficiency can be improved significantly. The converter also provides a wide range of voltage conversion ratios including fractional as well as VMC numbers and switch duty cycle. The topologies, operation principles, working characteristics and voltage conversion ratio are analysed in detail. A 500 W experimental prototype with two VMCs has been developed to validate the effectiveness of the theoretical analysis, and the highest efficiency is 93.8%.

A Generic Control-Oriented Model Order Reduction Approach for High Step-Up DC/DC Converters Based on Voltage Multiplier

“…Hence, each VM capacitor can be replaced by a controlled voltage source associated with u o . As the system order is determined by the number of the energy storage Energies 2019, 12,1971 3 of 17 components in the circuit, the corresponding model order can be greatly reduced. Detailed procedure for the proposed model order reduction approach is described as follows:…”

“…Step 3: Reformulate and simplify the resulting model to construct an equivalent reduced-order circuit based on the state-space averaging method [28]. In this connection, the converter proposed in [12] will be used as an example to demonstrate the proposed approach. Figure 3a shows the topology of this converter with n number of basic VM cells.…”

“…According to Step 2 of the proposed model order reduction method, the equivalent circuit of this converter by replacing all capacitors in VMs with corresponding controlled voltage sources is shown in Figure 3b. In this connection, the converter proposed in [12] will be used as an example to demonstrate the proposed approach. Figure 3a shows the topology of this converter with n number of basic VM cells.…”

“…In recent years, various VM circuits have been proposed to achieve a family of high step-up non-isolated DC/DC converter topologies for the applications in renewables [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. A generalized circuit structure of a family of non-isolated converters with VM is shown in Figure 1, where the switch/inductor circuit is connected to the diode-capacitor VM to supply the load R L .…”

“…The output voltage u o of the converter can be stepped up to much higher level compared to the input voltage u in . For the diode-capacitor VM circuit, voltage doubler circuit [7], voltage quadrupler circuit [8], Dickson charge pump [9], Cockcroft-Walton VM [10], and amongst others [17] have been used, and based on which various other different VM circuits have been proposed for two-input-phase interleaved booster converter [5,[11][12][13] and multiple-input-phase booster converter [4,[14][15][16]19]. Coupled-inductor has been used to replace the inductors to provide further performance improvement [6,23,24].…”