# A Study of Order Modification for Reactive Power Support by Wind Farm during Communication Failure
## 4 Conclusions  
A reactive power reference modification method for wind farms, based on a previous allocating system, was introduced. The basic theory of the allocation method was derived from a selected loss minimization technique. The modification has followed the utilized proportional allocating plan, and shown conformity, in terms of a self-updating process for reactive power references. Even if a \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Classification**} & **Proposed** & \multirow{2}{*}{**Iteration Number**} & **Finalized Reactive** & **Saturated** \\  & **Controller** & & **Supply [MVAR]** & **Voltage-PCC [p.u.]** \\ \hline Case A & - & - & 100 & 1.015 \\ \hline \multirow{2}{*}{Case B} & None & - & 49.66 & 0.99 \\  & Applied & 5 & 90.67 & 1.01 \\ \hline \multirow{2}{*}{Case C} & None & - & 36.72 & 0.986 \\  & Applied & 7 & 82.5 & 0.99 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Measured result of each case study. Figure 12: Reactive power supply from array 1 and voltage condition in case C—modified algorithm, with (**a**) reactive power supply, and (**b**) voltage variation. general wind system does not require an active support mode, in terms of reactive power, self-diagnosis algorithms for large-scale distribution networks can help to avoid communication errors. The order modification can be expanded to similar order management methods, and here, utilized a reactive power management process, analyzed some case studies. The general even-dispatch method was not considered in case studies due to the fact the designed network considered 50 WTs (since every WT display same profile modification, when we consider its scale, it is inappropriate analysis). From our simulations, it can be deduced that the modified reference signal contributes to the stabilized condition of the connection point. Since reactive power will be a major ancillary service in future wind farm systems, these support capabilities must be backed up by an additional security algorithm. This work was supported by Korea Electric Power Corporation grant (R17 XA05-4) and Human Resources Program in Energy Technology of the Korea Institute of Energy Technology Evaluation and Planning granted financial resource from the Ministry of Trade, Industry & Energy, Korea (No. 20174030201540). The main optimization algorithm and modification method were proposed by [PERSON]. The experiment results were collected and analyzed by [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON]. The authors declare no conflict of interest. [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Power capability investigation based on electrothermal models of press-pack IGBT three-level NPC and ANPC VSCs for multimegawatt wind turbines. _IEEE Trans. Power Electron._**2012**, _27_, 3195-3206. [CrossRef]
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