It has been well over thirty years since dissolved gas analysis, DGA, was introduced as a diagnostic tool for monitoring mineral oil filled transformers. It is now universally accepted as the method of choice to locate incipient thermal and electrical faults. DGA methodology and applicability have evolved significantly since its inception. The evolutionary development includes new laboratory me...

The optimal tap selection of transformers directly connected to generators is one of the two significant industry problems. The generator stepup and auxiliary transformers generally are equipped with no-load (fixed) taps that are infrequently changed. Their optimum positions need to be determined for meeting power system discrete states over long periods, covering the annual light-load, peak-lo...

This paper deals with a medium-voltage distribution network. The feeders in the open-loop arrangement are changed to the closed-loop arrangement with the aim to improve reliability of the power supply. The paper focuses on the analysis of transient and steady-state operation in the closed-loop that is established by connecting feeders supplied from two different transformers located in the same...

Distribution smart grid is very important part of the smart grid. Utilities use Distribution Management System (DMS) as supervisory control layer at the power system control centers. State Estimation (SE) and Volt-Var Control (VVC) are the prime applications of the DMS. In the modern DMS, SE is required for extensive monitoring and control of the entire distribution network. In the presence of ...

Optimal Reactive Power Dispatch (ORPD) is a multi-variable problem with nonlinear constraints and continuous/discrete decision variables. Due to the stochastic behavior of loads, the ORPD requires a probabilistic mathematical model. In this paper, Monte Carlo Simulation (MCS) is used for modeling of load uncertainties in the ORPD problem. The problem is formulated as a nonlinear constrained mul...

The optimal reactive power dispatch (ORPD) is a very important problem aspect of power system planning and is a highly nonlinear, non-convex optimization problem because consist of both continuous and discrete control variables. Since the power system has inherent uncertainty, hereby, this paper presents both of the deterministic and stochastic models for ORPD problem in multi objective and sin...

Voltage stability issues are growing challenges in many modern power systems. This paper proposes optimizing the size and location of Static VAR Compensator (SVC) devices using a Fuzzy Weighted Seeker Optimization Algorithm (FWSOA), as an effective solution to overcome such issues. Although the primary purpose of SVC is bus voltage regulation, it can also be useful for voltage stability enhance...

Turning to Renewable Energy Sources (RES) is the most logical politics in securing the modern society from critical changes in earth increasing temperature. However, Distributed Generation (DG) sources could lead to new challenges in electricity network, mainly allocation of DG sources in distribution level of power system will set the existing network under stress of power flow parameters. The...