Power Flow Analyze for Wind-Farm which using Induction Generator Technique (WTIG) via Computer Programs

In this research we give a pattern that explain how to simulate the wind farms via Etab. We use induction generator technique (WTIG). We can see through results that this method is the best way in reducing the power losses and building-cost.

Analyze The Role of Inductors on Power flow between Power Electronic Devices and Electric Grid

Power Flow control is very important procedure when renewable sources are connected to electric grid. Furthermore, Most common topologies of grid tied distributed generation have inductor attached to power converters. In this article, the role of inductors linking between power converters and electric grid is analyzed. Values of these inductors can affect largely the value of Power flow (Active and Reactive power) in both sides, while phase angle between voltage of terminals determines the direction of power flow. This paper proposes MATLAB/SIMULINK models to study this impact, for different operation conditions (four quadrants I-V curves). Two methods of coils calculation are applied, in order to design the best value calculated in the proposed MATLAB/SIMULINK models.

Impact of Reactive Compensators on Performance of Distance Protective Relays

This paper tries to clarify the impact of parallel and serial compensation of power transmission lines on the performance of distance relays which protect these lines. To this end, power system analysis software (NEPLAN) will be used for explaining distance relay behavior in the presence of different parallel or serial reactive power compensators, with main types of faults that may occur in different locations on the protected line. In this paper, Syrian power transmission network is simulated using (NEPLAN) software, and three reactive power compensators: parallel (STATCOM), serial (TCSC), and unified (UPFC), are used to compensate reactive power on transmission line. Several simulations, in many cases are carried out to illustrate the impact of fault type and location on the measured impedance seen by the distance relay. The objective of identifying the impact of reactive compensators on fault impedance seen by distance relay (i.e. fault location), is to determine the possible ways to resolve the problem and improve the performance of transmission line protection.

Application of Fuzzy Logic Controller for Unified Power Flow Controller

Unified Power Flow Controller (UPFC) is one of the most effective Flexible AC Transmission Systems (FACTS) devices for controlling power flow and improving stability of power system. To achieve the functionality of UPFC, a proper and sufficient control system should be designed for this device. Our research proposes a Fuzzy Logic control approach to control UPFC. The proposed control scheme is used to control and coordinate voltage and phase angle signals of Voltage Source Converters (VSCs) of UPFC, where these two signals are used to control active and reactive power flow in transmission line. To validate the proposed control scheme, a single-machine double line infinite bus power system equipped with UPFC is modeled using PSCAD/EMTDC software package. Three phase fault with ground case is simulated and investigated under the proposed controller. The modeling and simulation results show the effectiveness of the UPFC under the proposed control scheme for improving power system stability under the three phase fault case. The results also show the robustness and superiority of the proposed controller compared to conventional PI controller as well as it guarantees the closed-loop stability system and has a good tracking behavior.

Service Restoration of Electrical Distribution Systems to Increase the Reliability Using Genetic Algorithms

With the increasing use of technologies and automation in different sides of modern life, the outage of electricity became a big issue that widely affects the daily life of most sectors like industrial, economical or even entertaining sector. So it became so necessary to achieve a high-reliability electrical system to insure the continuation of electricity supply to the end consumer. Consequently, in this research, we are studying a new method of service restoration using genetic algorithms to increase the reliability of distribution systems and improving its performance. The research includes a brief aver view of electrical systems reliability and the basics of Genetic Algorithms and the use of these techniques in dispatching centers. In addition we have designed a program in "MATLAB" environment to apply the service restoration technique using genetic algorithms, and the program has been tested on a case study with the relative results shown .