Systematic analysis of control techniques for the dual active bridge converter in photovoltaic applications

SummaryAiming to the problems of high circulating current and low efficiency caused by the traditional strategy of dual active bridge (DAB) converter under light load, in this paper, simple graphical optimization method (GSO) is proposed to improve the efficiency of dual active bridge converter. Through the contour plot of transmission power and current stress, optimal efficiency point can be obtained by tangent of contour map under condition of constant power, and heavily calculation or complex iterations of existing conventional control strategies are avoided. Moreover, analysis of proposed graphical current stress optimization is addressed, and controller design of proposed method is given and described. Efficiency comparison between traditional modulation strategy and GSO is given to show the advantage of proposed mothed. An experimental prototype is built to verify the analysis.

Section: Introductionmentioning

confidence: 99%

Efficiency improvement of dual active bridge converter using simple graphical optimization method

Chen,

Zheng,

Tang

et al. 2023

“…When the voltage conversion ratio is other than unity, the converter undergoes high current stress, and the soft‐switching range of the converter is also reduced. To overcome these issues, advanced modulation schemes such as extended phase shift modulation (EPS), 7 dual‐phase shift modulation (DPS), 8 and triple‐phase shift modulation (TPS) 9 have been developed. There are also other modulation schemes such as hybrid modulation, 10 dual‐phase shift modulation, 11 unified TPS, 12 and so on.…”

Section: Introductionmentioning

confidence: 99%

“…High efficient and reliable DAB can be achieved by modifying the performance indices through the modulation scheme or circuit configuration. Among the reported modulation schemes, [6][7][8][9][10][11][12] the most popular and widely used is single phase shift (SPS) modulation 6 ; however, it has better operating performance only when the voltage conversion ratio is unity. When the voltage conversion ratio is other than unity, the converter undergoes high current stress, and the soft-switching range of the converter is also reduced.…”

mentioning

confidence: 99%

A quintuple phase shift modulation scheme in multilevel dual active bridge converter for battery energy storage system

Bheemraj

Karthikeyan

Kumaravel

2022

Generally, the dual active bridge (DAB) bidirectional DC-DC converter suffers from harmonics in the high-frequency link (HFL) conversion stage while operating under any modulation scheme. This paper proposes a quintuple phase shift (QPS) modulation scheme to suppress the harmonics under the whole operating range. A bidirectional auxiliary switch in the low voltage bridge produces a five-level output, which alleviates harmonic components of HFL current. The total harmonic distortion (THD) analysis is done for various operating conditions and is compared with the conventional modulation scheme, such as single phase shift and dual phase shift. The THD can be reduced in the entire power transmission for the proposed modulation scheme by defining the suitable phase shift ratios. Also, the power flow analysis under QPS modulation is reported in this paper. To validate the proposed approach's theoretical performance, simulation results are obtained under different operating conditions and verified with experimental results. The QPS modulation is implemented using the Spartan 3AN FPGA processor.

“…Since the DC bus supports several levels of voltage, demands and resources can be linked to either the greater or lesser dc voltage level, which is an effective solution in many situations. For example, voltage boosting is required to link photovoltaic (PV) 9,10 resources to the dc bus; but, whenever a minimum dc-link is available, linking PV to this reduced voltage eliminates the need for further boosting in voltage, costs of the converter, and volume. [11][12][13] Multilevel converters (MLC), such as ILC, provide several dc voltages levels dependent on its construction, making voltage balancing more difficult.…”

Section: Introductionmentioning

confidence: 99%

Implementation of hardware‐in‐loop for DC‐link voltage balancing in hybrid ac/dc microgrid using interlinking converter

Vasantharaj

Indragandhi

2022

Bipolar hybrid ac/dc microgrid (MG) controls a DC and AC bus at the same time, supplies local loads with local resources, and offers multiple levels of dc voltages to resources and services. The applications are getting more popular in power systems. Due to its vital tasks in numerous applications, the interlinking converter (ILC) is an utmost crucial portion of the MG system. From this study, a 10‐switch converter is provided as an ILC for a hybrid MG, which gains from both two‐level (2L) and three‐level (3L) converters at the same time, and it can be used to a wider range of power levels. This work provides a space vector modulation (SVM) for a 10‐switch converter to maximize dc‐link voltage consumption and minimize total harmonic distortion (THD) compared with other modulation techniques. The behaviour of the suggested SVM is compared with that of sinusoidal PWM. The suggested SVM was evaluated using OPAL‐RT to show that it used DC bus voltage more reliably and produced significantly less THD than existing techniques. Furthermore, grid‐tied ILC's architecture is improved to reduce low‐order harmonics and used for dc‐link voltage balancing. A real‐time (RT) digital simulator (OP‐5700) was used to test the inverter control technique. In MG, this hardware‐in‐the‐loop simulation provides an excellent environment for designing and verifying system‐level control algorithms. Simulations were run in a MATLAB/Simulink environment and confirmed using an RT simulator to validate the feasibility of the suggested topology.