The paper describes the digital twin of a Li-ion battery cell based on the MATLAB/Simulink generic model. The digital twin is based on measured data for constant current/constant voltage charging and discharging cycles with State of Health (SoH) up to 79%, also including fast charging. Mathematical equations used for the digital twin are obtained by 3D data fitting of measured SoH, battery capacity, and battery cell current. The input to the proposed digital twin is only the measured battery cell current, and its output includes State of Charge (SoC), SoH, and battery cell voltage. The designed digital twin is tested and compared with MATLAB/Simulink generic model and battery cell measurements for constant discharging current and dynamically generated discharging current profile. The results show significant improvement in the generic MATLAB/Simulink model.

This paper describes a high-frequency soft-switching dc-dc converter with a simple energy recovery capacitor snubber on the secondary side. The presented dc-dc full-bridge converter with the energy recovery snubber removes the main drawbacks of the classic Phase Shifted PWM (PS-PWM) dc-dc converter, e.g., the circulating current flowing during the free-wheeling interval and dependency of the soft switching on the load current. The converter utilizes a full-bridge topology with pulse-width modulation and a centre-tapped full-wave controlled rectifier with one active switch. The zero-voltage switching on the primary side is ensured by utilising only the magnetizing current of the high-frequency transformer, and thus is load-independent. The proposed energy recovery snubber is described in detailed time waveforms of the converter and verified by simulation. The control algorithm also removes the circulating current, which is typical for PS-PWM converters. The soft-switching of the secondary side transistor is achieved by a simple capacitor snubber with an energy-recovery circuit connected to the output of the dc-dc converter. The principle of operation is verified by measurements on a 2 kW, 50 kHz laboratory model of the proposed dc-dc converter.

This paper introduces a design of a modular multiport converter, employing active bridges. The design incorporates a modular structure, and the paper begins by conducting steady state analyses to evaluate the converter’s characteristics. Subsequently, a RMS current equation, average current equation and power distribution equation are derived. From these equations is derived equation for delay of specific port. Lastly, a multi active bridge described in this way is verified by simulation.

Multiport power converters are used to connect various types of energy sources and loads. These sources are usually connected via DC-DC converters to a common DC bus. However, such approach requires multiple power conversions, which reduces the efficiency of the whole system. The article describes a multiport converter with a parallel connection of transformers. The proposed topology uses a smaller number of power conversions, which increases the efficiency of the whole system. Furthermore, the topology allows easy addition or removal of next power sources or loads. A new approach is also used in deriving of a converter mathematical model. The proposed control allows the transfer of energy between arbitrary converter ports. The proposed topology and its control were verified by simulation, and the results are presented in the article.

Paper explores the Multi-Active Bridge (MAB) converter, offering scalability and modularity through interconnected modules. It analyzes the relationship between input currents, phase shift, voltages, and constructive parameters, examining power distribution and the impact of adding modules. Simulation results demonstrate power redistribution, while experimental results confirm feasibility. The study showcases the potential of MAB converters for diverse power source systems, emphasizing their flexibility.