A Multiple-Phase-Shift Control for a SiC-Based EV Charger to Optimize the Light-Load Efficiency, Current Stress, and Power Quality

With the development of the more/All electrical aircraft technology, the dual active bridge converter has been applied to the energy storage device to realize the bidirectional power flow in aircraft electrical system. The power loss of power device in DAB converter affects the operational life of the device and the reliability of the converter. So it is an important performance index to keep the temperature balance for power device in DAB converter. In this paper, the operational mode of dual active bridge bidirectional DC-DC converter in extended-phase-shift (EPS) control is analyzed and verified by experiment, find the reasons for difficult to achieve soft-switching under light load conditions, then proposes a novel thermal balance phase-shift control strategy on the basis of EPS. Experimental methods in this paper are alternation control mode and temperature feedback control mode. The thermal image and temperature was analyzed. The efficiency curve was plotted. The switching waveform was observed. the thermal balance was achieved to verify the effectiveness. and finally achieves the goal for improving the converter efficiency, reduces the devices heat stress, improves the reliability of the DAB converters and increases device lifetime.

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Multi-Objective Unified Optimal Control Strategy for DAB Converters with Triple-Phase-Shift Control

Energies ◽

10.3390/en14206444 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6444

Author(s):

Jinhui Zeng ◽

Yao Rao ◽

Zheng Lan ◽

Dong He ◽

Fan Xiao ◽

...

Keyword(s):

Optimal Control ◽

Phase Shift ◽

Dynamic Response ◽

Control Strategy ◽

High Efficiency ◽

Soft Switching ◽

Optimal Control Strategy ◽

Current Stress ◽

Multi Objective ◽

Shift Control

To solve the problems of large current stress, difficult soft-switching of all switches, and slow dynamic response of dual active bridge converters, a multi-objective unified optimal control strategy based on triple-phase-shift control was proposed. The forward power flow global modes of triple-phase-shift control were analyzed, and three high-efficiency modes were selected to establish the analytical models of current stress and soft-switching. Combined with these models, the optimal solutions in different modes were derived by using the cost function-optimization equation to overcome the limitation of the Lagrange multiplier method, such that the DAB converter achieved the minimum current stress, and all switches operated in the soft-switching state over the entire power range. At the same time, the virtual power component was introduced in the phase-shift ratio combination, which improved the dynamic response of output voltage under the input voltage or load steps changed by power control. The theoretical analysis and experimental results show that the proposed control strategy can optimize the performance of the DAB converter from three aspects, such as current stress, soft-switching, and dynamic response, which achieves multi-objective optimization of the steady-state and dynamic performance of DAB converters.

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Research on Marine DAB bidirectional DC converter based on DPS

E3S Web of Conferences ◽

10.1051/e3sconf/202124802064 ◽

2021 ◽

Vol 248 ◽

pp. 02064

Author(s):

Chang Li ◽

Xujing Tang ◽

Zhongze Zhang ◽

Yupeng Yuan

Keyword(s):

Phase Shift ◽

Power System ◽

Control Algorithm ◽

Power Transmission ◽

Control Method ◽

Mode Switching ◽

Hybrid Power System ◽

Current Stress ◽

Hybrid Power ◽

Shift Control

This paper takes the application of bidirectional DC-DC converter in Marine hybrid power system as the background, the problems of high reflow power and current stress in dual active bridge converter under traditional phase shift control are studied in this paper. Based on the dual phase shift control strategy, the power transmission optimization algorithm model is analyzed and derived, and a control method for optimizing mode switching is proposed. The optimized control algorithm is validated by Matlab/Simulink simulation experiment. The results show that the reflow power and current stress optimization control algorithm can effectively reduce the reflow power and the current stress of the converter, so as to improve the operation performance of DAB converter in high-power ship hybrid power system.

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Optimal Strategy of Triple Phase Shift Transient DC Bias for Dual Active Bridge DC-DC Converter

E3S Web of Conferences ◽

10.1051/e3sconf/202018501088 ◽

2020 ◽

Vol 185 ◽

pp. 01088

Author(s):

Jingyu Zhai ◽

Fusheng Wang ◽

Lizhong Ye ◽

Rui Li

Keyword(s):

Phase Shift ◽

Optimal Strategy ◽

Transition Process ◽

Stable Operation ◽

Current Stress ◽

Dual Active Bridge ◽

Shift Control ◽

Bias Model ◽

Dc Bias ◽

Simulation Results

Under the traditional phase shift control, dual active bridge DC-DC converter (DAB) has a transient bias on the inductance current when the phase shift ratio changes suddenly, which leads to increase in the current stress of switch tubes and even unidirectional saturation of the transformer. All those will affect the stable operation of the converter. This paper focuses on quantifying the transient DC bias model on the control of triple phase shift when phase shift ratios change, and then the strategy proposed by the paper can eliminate the DC bias within one switching period and reduce current stress and response time by adjusting the drive signal during the transient transition process. Finally, the proposed strategy is verified by simulation results from Matlab/Simulink software.

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