## 1 Introduction
Since DG is targeted to be used to boost the inadequate voltage, investigation is based on the voltage profile with DG and without DG [11; 27; 28; 29]. A significant amount of effort has been made by existing research studies to optimize voltage profiles and losses in distribution networks dominated by DG [7; 13; 19; 24; 29; 30; 31]. The influence of DG integration on voltage profile was explicitly investigated by the authors of [32] who discovered in their study that without DG, the voltage drops as the distance from either the generator or the transformer increases. In [20], a graph-based approach was explored to depict the trends associated with the change in voltage magnitudes from 1.1 pu to 0.9 pu when no DG was integrated into the system and the increase in voltage magnitudes above 1.1 pu when DG was integrated. In the study carried out by the authors of [33], it was proposed that the point of connection of DG, considering the high penetration levels to the distribution grid, caused issues with the voltage profile of a designed distribution feeder. Furthermore, the authors of [34] argued that the installation of DG, irrespective of the size, was highly capable of creating conflict with the operational routine of systems. Inherently, the interconnection of DG, irrespective of size, has an effect on the distribution voltage, but there is a range, however, of how much DG can be added to an existingsystem without significant incremental costs. There are system operations that conflict with the interconnection of DG, but researchers are more critical of voltage profiles. The study carried out by the authors of [35] used fault clearing and a reclosing approach to demonstrate the influence of DG on the system voltage profile. The results showed that challenges caused by voltage regulation often set the most restrictive limits on how much DG could be served from a particular feeder without making expensive changes. A static-analysis-based method was demonstrated by the authors of [36] to show that the penetration of DG units in a distribution network can lead to an increase or decrease in the system voltage stability margin with reference to the operational power factors and locations. The comparative study of this static-analysis-based approach and the proximity to the voltage collapse was carried out by the author of [15]. It was discovered that static-analysis-based approaches do not have the capability of determining the control action or the interaction between the DG units integrated into a system. However, the proximity to the voltage instability scheme could easily be adapted to identify the associated issues. The question now is how then can stability be achieved in a distribution system with a DG connection. According to [18], there are two ways a desired voltage level can be achieved and maintained with a DG connection. One is by directly controlling the voltages, that is, by use of a step voltage regulator and on load tap changers (OLTC). Another is by indirectly controlling the flow of reactive power in the feeder. The study presented in [37] suggested that the instability in voltage in a distribution system can be checked by appropriately sizing the load at the DG unit. From the above, voltage instability and flicker caused by a DG interconnection are solvable by both electrical and electronic devices and by the use of an appropriate DG penetration level. Although various contributions have been made using different approaches to solve this problem, the main bottleneck associated with all the existing studies lies in the fact that the approaches deployed in the identification of suitable locations for DG placement are iterative-based. The challenges associated with these iterative-based procedures are enormous. One such issue is the divergence of solutions coupled with the repetitive re-factorization of matrices. Another problem with such methods is the fact that the solution obtained is usually a local solution instead of a global solution. The information obtained from such approaches could be misleading.