Abstract

Successful and economical operation of industries is a fundamental object of society. The relevance of Power Quality (PQ) issue has recently augmented because of the increased use of power electronic equipments, which results in a voltage deviation and current waveforms. The performance and life expectancy of industrial electronics and electrical equipments is significantly affected by power supply anomalies caused by "Polluting" loads at an industrial site and by utility normal operational activities. With the level of future demand of electricity remaining unclear, power market players are reluctant to commit to long term capital investment. Distribution and generation using renewable energy resources such as wind and solar energy attract attention. Renewable energy resource plants must provide Power Quality required to ensure stability and reliability of the power system.

Although many operational aspects affect renewable energy source plants operation, this paper focuses on Power Quality and compensation methods adopted in renewable energy source plants as a literature survey. The paper also discussed on distributed generators control strategies and power sharing methods.

Abstract

This paper discusses the different strategies which enable wind power market to enhance reliability to integrate competitive power grids economically. Wind mills are newly globalized techniques to the Restructured Power Systems that are difficult to schedule due to variability and un-predictability. Now a day’s Wind energy is termed as Price Taker due to the issues like Transmission Congestions. Although Locational Marginal Pricing (LMP) plays an important role in many restructured wholesale power markets, the detailed derivation of LMPs as actually used in industry practice is not presently available. This paper demonstrates these problems by two sections. Firstly, the overview, definitions, characteristics, settlements, observations and examples for the Locational Marginal Prices or LMPs for particular generators that are developed on the basis of congested and uncongested case. Secondly, calculation for AC and DC optimal power flow models. Wind energy generation system for Restructured Power Systems is simulated using MATLAB

Abstract

For efficient operation of Distributed Generation (DG) is an essential aspect in future smart power grid. Distributed Generation is the interconnection of renewable sources that producing energy to the utility grid. A microgrid consists of both sources and loads. A microgrid can be operated in two modes. There are grid connected mode and islanded mode. A conventional controller (PI and PID) is proposed for the two modes of operation. During grid connected operation, all DG inverter system in the microgrid works in constant current control mode so as to supplies a constant power to the utility grid. When the system is detached from the main, all DG inverter system produces the power to the load and it should be switched to a voltage control mode because the voltage should not be regulated by utility. During this mode, the microgrid will supply a steady voltage to the local load. The smooth transition from grid connected to islanding mode and also reduce the transition time is the main objective of this work. The transition between grid connected and islanding modes performance when connected with and without controller is analyzed. A Phase locked loop (PLL) is used to determine the frequency and angle reference of the Point of Common Coupling (PCC). To assess the performance of the proposed control scheme MATLAB/SIMULINK tool is used.

Abstract

Unified power flow controller is a new concept for the compensation and effective power flow management of multi-line transmission systems. The UPFC employs a number of Voltage Sourced Converters (VSCs) linked at the same DC terminal, each of which can provide series compensation for the selected line of the transmission system. Through common dc link, any inverters within the UPFC is able to transfer real power  to any other and thereby facilitate  real power transfer among the line. In this paper the UPFC system used for power flow management at different angles. The prototype UPFC system was developed and verified with hardware results. When the voltage sag is compensated, reactive power is controlled and transmission line efficiency is improved.

Abstract

Renewable energy sources have attracted wide attention because of being abundant in nature and nearly non pollutant. Wind power is one of the most promising clean energy sources it can easily be captured by wind generators with high power capacity. Solar power is another promising clean energy sources in global system and can be harnessed easily. Solar energy system might be compensate the wind intermittency generation resource due to lesser start up time, lower operating cost and good ramping capabilities. The generation scheduling for wind-solar energy with thermal unit system in deregulated environment, minimize the total thermal fuel cost emission and maximize the profit of generation companies, subject to many constraints. While performing the generation scheduling problem by Lagrangian relaxation based particle swarm optimization method the hourly load, wind velocity and solar radiation must be forecasted to prevent the errors. The generation scheduling formulations are involved the perspective of a generation company (GENCO). The deregulation environment is one which the generation, transmission and distribution does not depend on each other. To demonstrate the uncertainty in the proposed method the generating scheduling problem is performed in a simplified generation system.