Nauris Jankovskis

Stochastic planning of distribution lines

The distribution line planning task has become more complex due to several impacting factors. This paper presents a stochastic approach for implementing an optimization procedure with a statistical representation of the electricity prices, ambient temperature and load currents in the distribution network. The validation of this stochastic approach is based on the comparison results of both examined approaches (stochastic and deterministic), which are applied for the computation of the total average annual costs. Attention has been focused on reducing total average annual costs by optimizing the conductor profile of a power line and the transformer capacity. Thus, the Net Present Value of the total average annual costs can be evaluated during the planning period. The problem is formulated as a minimization of the Net Present Value of the total average annual costs of an examined distribution line project. The tool is implemented in MATLAB software by using the Monte Carlo method. The proposed stochastic approach has been applied in the solution of an example of a distribution line project, which is presented.

Cost-benefit analysis of simplified substations: A case study based on the Latvian conditions

The increased requirements regarding the quality of power supply as well as the development of the transmission and distribution power networks brings about the need to connect new consumers and generators to the already-built electric networks, and these can be situated far from the existing substations. This paper presents a cost-benefit analysis of three technical solutions including simplified substations for evaluating and choosing the optimal alternative of connecting new consumers at the pre-design stage of a project. The presented cost-benefit analysis is based on the results of a comparison of three examined solutions under four examples of calculation conditions. The average annual costs have to be minimized. Thus, the selection of a rationally substantiated electric layout for connecting the new consumers is an important issue that must be taken into account for meeting the necessary future grid challenges more effectively and economically.

A stochastic approach to the feasibility study for overhead power lines

This paper presents a stochastic optimization approach to the feasibility study for power lines, taking into account market conditions. To validate the proposed stochastic approach, an economic comparison of several power line design alternatives has been done, considering technical issues as well. The final evaluation and analysis was based on the results obtained by applying both approaches: the deterministic (classical) method and the stochastic one. Both methods are used for power line design including optimum selection of the main parameters of the line such as tower height, type and coordinates, conductor type and cross-section, line fittings etc. The optimization problem is formulated as minimization of the total annual operating and construction costs. The solution task is realized in MATLAB software by using the Monte Carlo method as well as in the overhead power line automation design system PLS-CADD.