## 4 Conclusions  
In this study, a model to be used in balanced or unbalanced distribution system load flow analysis for CFIG based WTGSs, which is directly connected to the grid, is developed, and it is also incorporated into a sweep based load flow analysis algorithm. The accuracy of the Developed model is experimentally evaluated and extensive validation is performed against the SCP Model [12] previously presented in the literature. Considering the experimental analysis results obtained under different voltage unbalance and rotor slip levels, it is found that the Developed Model successfully estimates the reactive power demand of the machine and provides a meaningful figure for the generated active power when compared with the measured values and the SCP Model [12]. Thus, it can be concluded that the Developed model is robust and facilitates the computation of real and reactive power outputs of the induction generator \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c}{**Developed Model**} & \multicolumn{2}{c}{**SCP Model [12]**} \\ \hline General Iteration & Maximum Machine Iteration & General Iteration & Maximum Machine Iteration \\ \hline
11 & 2 & 12 & 6 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Iteration number of models in the 34 bus test system. Figure 11: Executed operation numbers for models in the 34 bus test system analysis. for a specified wind speed and the terminal voltage by recognizing that machine equivalent circuit parameters are available. In addition, the Developed Model and the SCP Model [12] are used for the load flow analysis of the 34 bus unbalanced radial distribution test system. Accordingly, it is clearly pointed out that both models give results very close to the load flow results of the 34 bus test system provided by [PERSON] et al. [27]. Models are also compared in terms of operation number and complexity for the load flow analysis of the 34 bus test system. As a result, it is concluded that the Developed Model requires less iterations and number of operations when compared with the SCP Model [12]. This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under project number 112E222. [PERSON] designed and performed the experiments. [PERSON] performed the analyses and [PERSON] wrote the paper. [PERSON] and [PERSON] superise the whole work. The authors declare no conflict of interest. National Renewable Energy Action for Turkey. Available online: [[http://www.ebrd.com/documents/comms-and-bis/turkey-national-renewable-energy-action-plan.pdf](http://www.ebrd.com/documents/comms-and-bis/turkey-national-renewable-energy-action-plan.pdf)]([http://www.ebrd.com/documents/comms-and-bis/turkey-national-renewable-energy-action-plan.pdf](http://www.ebrd.com/documents/comms-and-bis/turkey-national-renewable-energy-action-plan.pdf)) (accessed on 25 January 2018). * [PERSON] (2015) [PERSON] _Alternative Energy in Power Electronics_, 1 st ed. ; Elsevier: Oxford, UK, 2015; ISBN 9780124167148. * [PERSON] et al. (2007) [PERSON]; [PERSON]; [PERSON]; [PERSON] Generators for wind energy conversion systems: State of the art and coming attractions. _J. Electr. Syst._**2007**, \(3\), 26-38. * [PERSON] (2017) [PERSON] Development of a decision-making algorithm for the optimum size and placement of distributed generation units in distribution networks. _Energies_**2017**, _10_, 1433. [CrossRef]
* [PERSON] et al. (2015) [PERSON]; [PERSON]; [PERSON] The impact of distributed generation in the distribution networks' voltage profile and energy losses. In Proceedings of the 9 th IEEE European Modelling Symposium (EMS), Madrid, Spain, 6-8 October 2015; pp. 260-265. [CrossRef]
* [PERSON] (2015) [PERSON] Incorporation of fixed speed wind turbine generators in load flow analysis of distribution systems. _Int. J. Renew. Energy Technol._**2015**, \(6\), 317-334. [CrossRef]
* [PERSON] and [PERSON] (2008) [PERSON]; [PERSON]. _Power Quality in Power Systems and Electrical Machines_, 1 st ed.