# A Low-Cost Evaluation Tool for Synchronization Methods in Three-Phase Power Systems
## 4 Conclusions  
This work presents a low-cost and versatile digital evaluation tool for the experimental evaluation of synchronization techniques. The evaluation tool emulates the voltage signals of an electric grid to be acquired and processed by any digital controller capable of implementing a synchronization algorithm. The emulator also generates reference signals to evaluate the synchronization algorithms implemented in a digital controller. The cost of the evaluation tool, considering the emulator platform, is in the low range compared to other tools (Table 1), at less than USD 100.  
The methodology of use presented here allows for the correct tool to be implemented and the algorithms to be evaluated when digital platforms are used. The evaluation considers steady-state and transient analyses of the voltage, frequency, and amplitude estimated by the synchronization algorithms using the OS, \(t_{s}\), ME, and RMSE. The calculated execution time is another indicator considered in the evaluation of algorithms. The methodology is replicable on different digital platforms and allows different disturbance ranges to be set, including those defined by electrical standards and regulations.  
The proposal was validated through an experimental implementation of the evaluation tool through the LAUNCHXL-F28379D platform. The emulator allows for the validation of digital synchronization algorithms such as SRF-PLL and DSOGI-PLL with LPF by implementing them in a digital controller (Arduino Due platform), varying the amplitude and the frequency and considering the harmonic content. The experimental results confirmed the performance of the algorithms reported in [8; 29]. In particular, the high impact of harmonics on SRF-PLL (Figures 15(a) and 15(b)) and the longer execution time of DSOGI-PPL (Table 10) were verified. The execution time of DSOGI with LPF was 91% longer than that of SRF-PLL (63.61 \(\mu\)s vs. 33.17 \(\mu\)s).  
Conceptualization, M.E.R., P.E.M. and E.E.; methodology, M.E.R., P.E.M., C.R.B. and C.P.; software, M.E.R. and P.E.M.; validation, M.E.R. and P.E.M.; formal analysis, M.E.R. and P.E.M.; resources, P.E.M.; writing--original draft preparation, M.E.R. and P.E.M.; writing--review and editing, M.E.R., P.E.M., E.E., C.R.B. and C.P.; visualization, M.E.R., P.E.M. and B.C.; supervision, P.E.M. All authors have read and agreed to the published version of the manuscript.  
The Chilean Government funded this research through the ANID BECAS/DOCTORADO NACIONAL 21231463 scholarship, ANID/FONDEQUIP/EQM210178, and UBB INN I+D 23-54.  
Not applicable.  
The data presented in this study are available on request from the corresponding author due to privacy restrictions.  
The authors would like to thank the Laboratorio de Acondicionamiento y Conversion de Energia (LACE) at the Universidad del Bio-Bio, Chile, and Thematic Network RIBIERSE-CYTED 723 RT0150, for technical support.  
The authors declare no conflicts of interest.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} RESs & renewable energy sources \\ DERs & distributed energy resources \\ ESSs & energy storage systems \\ PLL & phase-locked loop \\ \end{tabular}