# Modern MultiPort Converter Technologies: A Systematic Review
## 2 General Classification and Operation Principles
### Partially-Isolated Multiport Converters  
The so-called partially isolated multiport converters represent a different category of multiport converters (Figure 5). The single winding of the high-frequency transformer can be connected to the input power port of an isolated multiport converter. Connecting to the input ports' common ground point is required. This converter's topology can be described as a hybrid of fully isolated and non-isolated multiport topologies. High power density, adjustable voltage ranges, and galvanic isolation of the load from the primary side are only a few of the main benefits of partially isolated multiport converters. Many different partially isolated multiport converters have been developed as a result of the aforementioned benefits. Among the primary drawbacks of the partially isolated design is that it does not offer as much scope for voltage scaling as the completely isolated multiport system does. The study in [46] suggests an isolated multi-port converter that combines a series-resonant converter and a bidirectional pulse width modulation (PWM) converter. With the suggested multiport converter, the complexity and size of the circuit are reduced by integrating magnetic components in addition to halving the switch count. The proposed MPC was prototyped with 150 W power capacity for experimental verification. The single-magnetic topology is achieved by using the magnetizing inductance of the transformer as a filter inductor for the PWM converter and the leakage inductance as a resonant tank for the series resonant converter (SRC). The mathematical model of the partially isolated multiport converter was derived after a detailed study. In the battery charging mode, when the input power source delivers both the output and battery charging powers, the output and battery voltages are regulated via pulse frequency modulation (PFM) and PWM controls, respectively. In [47], a control method and power management for an integrated partially isolated three-port converter which connects a solar input port, a bidirectional battery port, and an isolated output port are presented by the authors. In order to achieve a smooth and seamless mode shift, a competitive method is applied. The converter's mathematical model under various operating modes is obtained in detail using the state-space averaging  
Figure 5: Structure of partially isolated double-input-double-output (DIDO) port system. \begin{table}
\begin{tabular}{p{142.3 pt} p{142.3 pt}} \hline \hline
**Isolation Type** & \multicolumn{1}{c}{**Main Results**} \\ \hline Isolated & By combining photovoltaic systems and the power grid, an integrated capacitor-inductor-inductor-inductor-capacitor (CLILC) resonant converter for plug-in electric vehicle (PEV) applications is proposed. The general topology, operational situations, and control system of the given converter are described. The converter is supposed for high-power applications. It has a cheap cost, and a wide range of output voltage. At the same time, as it was reported by the authors, it is possible to expand the converter operation modes. The entire system is controlled by a proposed integrated MIMO control system. \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._method, and a decoupling network is then implemented to permit different controller designs. Three circuit stages in the converter enable two control inputs to be used to govern two of the three ports. The input port or battery port can be regulated based on which is most urgently required given the available solar power and battery state of charge at any given time; however, the output voltage is always regulated. The multiport converter uses a matrix-based averaged state-space method for converter model derivation because there are numerous control inputs and state variables. Table 4 contains some of the research results regarding the implementation of various partially isolated multiport topologies.