## 5 Conclusions  
In this paper, a state-space model is established to measure the stability of each converter stage for determining the SST performance with and without a controller. The analysis is conducted in three phases. In an initial attempt, the state-space model of each converter is derived, and the state-space matrixes are defined. The controllability and observability states are measured to check the system's stability. Further, the frequency and time domain analyses are performed using the Bode plot, Nyquist, Nichols, and root locus plot. On the basis of these plots, the stability, DC gain, peak resonant, and eigenvalue of the system are measured. Furthermore, the proposed SST model is simulated through the Matlab SIMULINK environment, and the results are provided, validating the systems' characteristics and seen as smooth performances. Finally, the Simulink model has been validated using a real-time digital simulator, such as OPAL-RT, to show the effectiveness of the system.  
This study has particularly drawn attention to the transient performance and the stability of the system, which can be analyzed using the proposed approach, such as the state-space and transfer function-based model. The studied SST model can be implemented in distribution system applications that can cope with voltage disturbance. Besides, the SST can also manage voltage fluctuation due to intermittent sources, such as solar and wind, which, in fact, are necessary for small microgrids as they depend on 100% renewables. Moreover, the SST-based distribution system has numerous advantages, such as efficient power distribution, smart-grid realization, improved voltage regulation and stability, re  
Figure 12: Real-time validation results: (**a**) Source voltage. (**b**) Source current, (**c**) Load voltage (**d**) Load current, (**e**) DC-link voltage.  
duced environmental impact as it can enable renewable energy sources, and enhanced grid flexibility and adaptability. With the use of SST, energy providers can justify their investment to the end-user by offering resilience improvement of the distribution system by reducing the potential disturbances due to uncertainties.  
The research can be extended to the stability analysis of SST by incorporating renewable energy sources as a microgrid-based system from real-time application aspects. In this paper, we considered only constant load conditions; in the future, different load types will be considered with the impact from the stability point of view. In addition, the detailed state-space model of each converter stage will be analysed.  
Conceptualization, D.K.M. and M.H.A.; methodology, D.K.M.; software, D.K.M.; validation, D.K.M., S.P. and S.K.S.; formal analysis, D.K.M., M.E. and L.L.; investigation, D.K.M., M.E. and S.K.S.; resources, D.K.M. and J.Z.; data curation, D.K.M.; writing--original draft preparation, D.K.M. and M.E.; writing--review and editing, D.K.M., M.H.A., S.P. and J.Z.; visualization, D.K.M.; supervision, L.L. and J.Z.; project administration, D.K.M. and M.E.; funding acquisition, D.K.M., J.Z. and L.L. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The authors declare no conflicts of interest.