Circuitry and analysis of input‐capacitor‐added multiple‐input buck converters

Abstract

Characterised as more straightforward topology, less components and simpler control, multiple-input (MI) converters are becoming active to be studied and implemented in renewable energy hybrid systems (REHSs) in the recent decade. In this study, a complete and systematic circuitry analysis of conventional MI buck converter (MIBC) and input-capacitor-added (ICA) MIBC topologies is clarified. Proceeded from the derivation of the input current of the utilised power source, a series of general equations of both conventional and ICA MIBCs that describe the circuits' electrical characteristics and behaviours are deduced, in the form of the kth practical source and considering the influence of equivalent series resistor(s), which are not put forward in previous literatures. The value of k can be any positive integral theoretically. The accuracy of these formulas is verified by comparing with the test results, combined with which, the impacts of the four main circuit parameters on the power sources are also discussed. The introduction of ICA MIBC is aimed at showing its specific capabilities and advantages in applications of REHSs, beyond conventional MIBC topology. The circuitry analysis, the proposed equations and the comparing discussion in this study do practically benefit to theoretical research, industrial application and power budgeting of MIBC.

Exact steady‐state analysis in multiple‐input converters applied with diverse time‐sharing switching schemes

“…Owing to page limitation, MIbC is used to serve as an illustrative example because of its straightforward circuit configuration and high-frequent appearance in MIC applications [1,5,[7][8][9]13]. The contents of the paper are organised as follows: exact steady-state analysis and derivation in MIbC, based on TEM and IDEM TSS functions and operating in CCM and DCM, will be, respectively, discussed in Section 2; followed by the proposed generalisation procedures in Section 3, series of analytical expressions for rest of the MIC topologies besides MIbC could be established (two typical ones will be listed in Appendix); a MIbC prototype with two input legs will be implemented and studied for theoretical verification in Section 4; finally, conclusions will be drawn.…”

“…The identical relation to (5) between inputs and output is also available from the inductor volt-second balance principle [1,5,8,17,18]. Owing to the principle of iterative algorithm, the terms i L (t 1 ) to i L (t m+1 ) in (1) can be replaced with their upper sub-equations, finally uniformly expressed with the initial value, i L (t 0 ) (see (6) at the bottom of the next page)…”

High step‐up double input converter with soft switching and reduced number of semiconductors

“…This is the most prominent feature of this kind of converter, which can be observed in almost all of them . However, the converters in [29][30][31][32][33][34][35][36][37] have been lost sight of this feature. b.…”

“…In these converters, soft switching condition is usually lost [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][30][31][32][33][34][35][36], and voltage gain is relatively low [5, 7-18, 20-22, 29-36], but the number of semiconductors is few and power density is improved [6, 8-15, 20-22, 29-36].…”

“…This is the most prominent feature of this kind of converter, which can be observed in almost all of them [5–28]. However, the converters in [29–37] have been lost sight of this feature. Component sharing : this indicates the utilisation factor of each component in different operating modes. For instance, in [27, 28], the introduced converters utilised two full‐bridge converters, on each input port, which are magnetically coupled.…”