Series Stacked Modular DC–DC Converter Using Simple Voltage Balancing Method

Summary With the rapid development of power electronics technology, modular series‐parallel structures have attracted more and more attention due to high reliability and good redundancy. Especially in the occasion of high input voltage and low output voltage, the input‐series output‐parallel (ISOP) DC–DC converter is applied to reduce the stress of the device. Although this modular approach has many advantages, there is a problem of unbalanced voltage and current caused by component parameter errors in each module. Therefore, this paper proposes an inverse droop control equalization method based on coefficient adaptation. This method can not only keep the input voltage sharing (IVS) of the modules among the ISOP system but also solve the problem of the deviation of the traditional inverse droop control output voltage from the reference value, which increases the dynamic response of the system. This article first introduces the principle and control logic of the method and builds a three‐way module ISOP circuit. The experiment verifies the input voltage equalization effect and dynamic performance of the control method on the ISOP system under various working conditions.

Section: Introductionmentioning

confidence: 99%

Input‐series output‐parallel DC–DC converter based on adaptive coefficient voltage equalization control

Tang

Zhao

Shi

et al. 2022

Section: Introductionmentioning

confidence: 99%

“…In series connections, equilibrium is achieved by proper voltage distribution between modules. In parallel connections, however, the power balance is performed by ensuring the current sharing among the converters that are part of the system 4,5,9–30 …”

Section: Introductionmentioning

confidence: 99%

“…Modular systems offer several advantages to applications, such as a significant increase in converters reliability by introducing different levels of redundancy; the combination of modules of the same power allows for standardization of components, reducing manufacturing time and costs; increase the processed power by adding more modules in parallel; possibility of increased efficiency; among other advantages. 4,[9][10][11][12][13][14][15][16][17][18] There are four modular system architectures, which are employed according to the type of application: Input seriesoutput series (ISOS), input series-output parallel (ISOP), input parallel-output series (IPOS), and input parallel-output parallel (IPOP). [17][18][19][20][21][22][23] The modularity technique also brings challenges for its proper operation and the one is to ensure a balanced division of power among all modules.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Input parallel–output parallel connected modular nonisolated DC‐DC converters with current self‐sharing capability operating in discontinuous conduction mode

Kremes

Andrade

Bharatiraja

et al. 2022

This paper covers the self-sharing analysis of dc-dc nonisolated converters with input parallel-output parallel (IPOP) configuration and operating in discontinuous conduction mode (DCM). The main contribution of the proposed system is its capability of providing self-sharing of the currents on both sides of each individual converter, without average current sharing control, even in the face of parametric variations. This self-balance only occurs for DCM. When the addressed converters operate in continuous conduction mode (CCM), the self-sharing does not occur naturally under parametric differences among them, requiring the use of additional control loops. The use of self-sharing converters in nonisolated converters simplifies the control system, it makes the modular solution being attractive for many applications, and it increases the power range that the DCM converters may be applied. This paper brings the theoretical study of self-sharing of the current mechanism to six basic nonisolated converters operating in DCM. The self-sharing is verified by experimental results, which are obtained from three modules of dc-dc SEPIC converters. Both converters were designed to operate with 200-V input voltage, 125-V output voltage, 1500-W rated power (500 W each module), and switching frequency at 30 kHz.

“…6,7 On the other hand, the literature also presents solutions based on transformeless converters, which generally are simpler, less cost, less size, and higher efficient than the insulated ones. 6,8 Usually, to provide the dc-dc conversion of low-input voltage to high-output voltage, the traditional non-insulated dc-dc converters are associated with techniques applied to raise the gain, 9 such as coupled-inductors, 10,11 voltage multiplier (switched-inductor cell, 6,12 switchedcapacitor cell, 6,[12][13][14] elementary-lift cell, 9,15 and cascaded and stacked converters association [16][17][18] ).…”

Section: Introductionmentioning

confidence: 99%

High step‐up dc‐dc converter based on the differential connection of basic converters and switched‐capacitor cells

Andrade

Coelho

Lazzarin

2021

This paper proposes a differential connection between the conventional boost and the mirrored SEPIC converters and the combination of them using switched-capacitor cells. The integration results in a single stage power structure that provides high-voltage gain and high efficiency. The article approaches a detailed static-dynamic analysis and a comparison in relation to other structures presented in the literature. In addition, to corroborate the theoretical analysis and the operation stages of the proposed converter, a 200 W prototype, with a switching frequency at 50 kHz, an output voltage from 300 to 400 V and an input voltage of 20 V, is evaluated. An efficiency peak of 96.78% was reached at 100 W.