## 1 Introduction
### Allocation Problem of sectionalizing Units within Electrical Networks  
One of the important issues is the problem of efficient distribution of sectionalizing units, and there have, to date, been many scientific works aimed at its solution. Most research proposes the selection of installation places for protective devices in terms of increasing the reliability of power supply because the reliability indices are convenient for PS companies. In most cases, they are authorized by the Institute of Electrical and Electronics Engineers (IEEE) [16]. According to [17], the most widely utilized indices are the system average interruption frequency index (SAIFI), the system average interruption duration index (SAIDI), the customer average interruption duration index (CAIDI), and the average service availability index (ASAI). Thus, research [14] discusses ways to lower the SAIDI index for a feeder of 11 kV distribution system located in a remote place. The approaches are based on a reliability-network-equivalent model that takes into account the effects of feeder layout, the location of recloser, and the application of distributed generators. In paper [18], authors use only SAIFI reliability index in a method to predict reliability improvements, that is, a method for the determination of the quantity, type, and placement of protective devices. Authors in paper [19] also suggested solving the same problem relying on the SAIFI index but by application of a binary programming optimization with the usage of engineering heuristics algorithm in order to reduce the duration of calculation. However, already, in paper [20], the same scientific team extended their work by adding indices MAIFI (momentary average interruption event frequency index) and ASIFI (average system interruption frequency index). They proposed an improved method for reaching a compromise between a decrease in the SAIFI and ASIFI and an increase in MAIFI by identifying what protective scheme should be chosen. In paper [21], an increase in the efficiency of network protective design also correlates with lowering SAIFI and ASIFI indices, and a binary programming method is proposed to choose the type of protective apparatus at a predetermined position on a distribution feeder. Considering papers [22; 23; 24], it is also noted that, for the determination of protective device location in a distribution feeder, authors use non-linear binary programming models also based on the minimization of SAIFI and ASIFI indices. In [25], already, a set of three indices, SAIFI, SAIDI, and MAIFI, is taken into account within a method for placing an optimal number of reclosers, which are based on genetic algorithm (GA). Study [26] presents a methodology for the allocation of distributed generators and reclosers in a security-constrained distribution network through analyzing reliability indices SAIFI, SAIDI, and MAIFI and power flow equations. It should be noted that power flow analysis is a powerful tool to assess PS reliability [27] in order to solve such tasks as optimal network configuration [28; 29] and PS restoration process [30]. In spite of the fact that the majority of methods are based on the reliability indices listed above because they are well-known to PS companies and directly influenced by the number, type, and location of the protective devices, the indices reflecting the financial component are more precise due to the fact that they allow directly calculating the investment cost for the deployment of protective systems. For that reason, the authors in paper [8] propose using CENS index, showing the cost of electricity undersupply for the benefit assessment of protective system introduction. In paper [31], the authors present an optimization methodology to find the placement and types of protective devices, e.g., breakers, reclosers, and disconnecting switches. The methodology enables the identification of optimal SAIFI and SAIDI indices and the minimization of outage cost.