# Modern MultiPort Converter Technologies: A Systematic Review
## 4 Control Systems for Multiport Topologies
\begin{table}
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**Control Method** & **Main Results** \\ \hline Proportional integral (PI) & A novel asymmetrical dual-output zero current switching ZCS resonant topology for a single-input-multi-output converter is proposed. For a control system, a simple single-loop voltage-mode control block is proposed where a compensator is used to process an error signal produced by the reference comparison. Voltage-controlled oscillator (VCO) receives a control signal from the compensator. The driver circuitry receives the necessary switching frequency from the VCO. Either analog circuits or digital signal processors (DSP) can be used to realize VCO, compensator, and PWM. \\ \hline Proportional integral differential (PID) & The outputs of MPC are individually controlled, thus a change in load at one output cell will not have an impact on the other output cells that are connected to it. The primary control objective is constant current control. The input sources with direct duty-cycle controlled input cells can supply a certain amount of power by adjusting the duty cycles of the switches of the corresponding input cells when the constant current control is applied to some of the input cells. \\ \hline Model predictive voltage control (MPVC) & The cross-regulation issue, a crucial problem in some types of multiport converters, can be solved by the proposed MPVC approach. To validate the suggested MPVC technique, simulation and experimental approaches were applied for the single-inductor dual-output buck converter. Conducted experiments helped to test the method in steady-state operation and during a dynamic performance. The MPVC approach can produce the ideal control signals to considerably reduce cross-regulation. \\ \hline \end{tabular}
\end{table} 
Table 5: Application of different control methods for MPCs. an integrated solution, the experimental verifications were performed with discrete parts, with the digital control being implemented in a field-programmable gate array (FPGA). In [79], the authors suggest a hybrid space vector modulation technique (HSVM) for the multiport converters. In order to improve the converter efficiency, the authors also researched what happens if the auxiliary currents are shifted from the main ones. Three-phase 5 kW multiport converter prototype has been equipped with the suggested control circuit. It is demonstrated that the suggested HSVM method can increase the efficiency of a system in comparison to conventional space vector modulation by 0.3% at full load. The improvement is even more noticeable under partial loads, reaching up to 0.7%. Four-port converter is described in [80]. The PV array, fuel cells, and wind turbine are connected to the input side of the converter. The simplified bidirectional control structure is introduced. In the modulation strategy, the one-leg shoot-through procedure was adopted to decrease the switching losses and conduction losses of IGBTs. The system's control technique is designed to handle a variety of load fluctuations. Functions for output voltage stabilizing and current limiting are included in the proposed MPC's control system. In [81], for connecting multiple electric vehicles with energy-consuming households in DC microgrids (V2H), the T-type isolated multi-port converter (T-iMPC) interface topology is suggested. A control algorithm is designed to maintain balanced output voltages in order to verify the effectiveness of the converter operation. The suggested control system comprises several control loops that can run concurrently and in transition. Among these control loops are the DC-link control loop, FC control loop, constant current (CC) control loop, constant voltage (CV) control loop, and balance loop. Phase shift modulation is used in the DC-link control loop to distribute electricity to residences while maintaining the output DC-link voltage constant at 400 V. In an interleaved manner, the suggested T-iMPC may perform the functions of two bidirectional buck/boost converters.