A new interleaved ultra‐large gain converter for sustainable energy systems

Abstract

By inserting the secondary windings of the coupled inductors in series with the primary of the built-in transformer at the middle branch, a new concept is introduced for achieving ultra large voltage gain. The secondary and tertiary windings of the built-in transformer are inserted in the voltage multiplier cell. This configuration not only extends the voltage gain and minimises the voltage stress across power MOSFETs, but also gives a more flexibility to increase the voltage gain by the turns ratios of the built-in transformer and coupled inductors. Hence, high duty cycle is avoided and low voltage switches can be adopted which reduces the conduction losses. Also, the regenerative diode in each of the phases is connected to the other phase to improve equal current sharing performance. The energy of the leakage inductances is recycled by passive clamps and the high voltage spikes are avoided. Meanwhile, due to the leakage inductances of the magnetic means, the zero current switching of semiconductor devices is provided and the reverse recovery problem is alleviated. Finally, a 600 W prototype with 28-400 V voltage conversion and 97% conversion efficiency is built to demonstrate the performance of the converter.

Design of an Interleaved High Step-Up DC-DC Converter with Multiple Magnetic Devices for Renewable Energy Systems Applications

“…According to Figure 9(a), the voltage gain of the proposed converter with n � N � 1 is higher than the proposed converters in [38,43]. e presented converters in [28,35] have higher voltage gain than the proposed converter; however, as shown in Table 2, these converters have more number of components than the proposed converter. Moreover, Figure 9(b) shows the voltage stress across semiconductor devices versus different turns' ratio.…”

“…A performance comparison is made between the proposed converter and the previously presented interleaved converters in [28,31,35,[38][39][40][41]43]. e results are provided in Table 2 and Figure 9.…”

“…To use high voltage gain converters at high power, minimize the input current ripple, and increase reliability, interleaved converters have been introduced. e abovementioned structures (i.e., SC, CI, and VMC) are adopted to interleaved topologies to achieve high step-up voltage gain [27][28][29][30][31][32][33][34][35][36][37][38][39]. An interleaved boost converter with a bi-fold Dickson voltage multiplier is presented in [40], in which several diodes and capacitors are employed to increase the overall voltage gain.…”

Soft‐switching non‐isolated high step‐up three‐level boost converter using single magnetic element

“…Same problems exist in [8] along with using four power switches which degrades the power density and cost. In [11,12] interleaved high step-up converters using coupled inductors and voltage multiplying cells are introduced. Although in these converters the voltage gain is high, hard switching operation degrades the efficiency.…”

“…To increase the voltage gain of the boost converter and their derivatives, different methods like coupled-inductors and voltage multiplying cells are presented which can prevent converters from operating with high duty cycles [7]. In [8][9][10], different three-level high step-up boost converters and in [11][12][13][14][15], interleaved high step-up boost structures based on the abovementioned step-up methods are introduced. In [9], a coupled-inductor based three-level converter is introduced, the voltage gain is a bit higher than the conventional three-level and both switches have low voltage stress, however, diode reverse recovery losses considerably degrade the efficiency.…”