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P. Dinakara Prasad Reddy ¹, B. Chandra Sekhar ²

Affiliations
1 Department of EEE, Sri Venkateswara University, Tirupati-517502, Andhra Pradesh, IN
2 Senior Research Fellow, Energy Efficiency and Renewable Energy Division,CPRI, Bangalore - 560080, IN

Abstract

This paper presents a two stage approach that determines the optimal location and size of capacitors on radial distribution systems to improve voltage profile and to reduce the active power loss. In first stage, the capacitor locations can be found by using loss sensitivity method. Firefly algorithm is used for finding the optimal capacitor sizes in radial distribution systems. The sizes of the capacitors corresponding to maximum annual savings are determined by considering the cost of the capacitors. The proposed method is tested on 15-bus and 34-bus test systems and the results are presented.

Keywords

Capacitor placement, loss sensitivity method, firefly algorithm, radial distribution system

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P. Dinakara Prasad Reddy ¹, V. C. Veera Reddy ², T. Gowri Manohar ³, B. Chandra Sekhar ⁴

Affiliations
1 Research Scholar(JNTUK), Department of EEE, S V University College of Engineering, S V University, Tirupati-517502, IN
2 Professor, EEE Department, AITS, Tirupati-517502, IN
3 Professor, S V University College of Engineering, S V University, Tirupati-517502, IN
4 Senior Research Fellow, Energy Efficiency & Renewable Engineering Division, Central Power Research Institute, Bangalore-560080, IN

Abstract

Distributed Generator (DG) resources are small electric generating plants that can provide power to homes, businesses or industrial facilities in distribution feeders. By optimal placement of DG we can reduce power loss and improve the voltage profile. However, the values of DGs are largely dependent on their types, sizes and locations as they were installed in distribution feeders. The main contribution of the paper is to find the optimal locations of DG units and sizes. Index vector method is used for optimal DG locations. In this paper new optimization algorithm i.e. Grey wolf optimization algorithm is proposed to determine the optimal DG size. This paper uses three different types of DG units for compensation. The proposed methods have been tested on 15-bus, 34-bus, and 69-bus radial distribution systems. MATLAB^TM, Version 8.3 software is used for simulation.

Keywords

Grey Wolf Optimization Algorithm, Index Vector Method, Distributed Generation Placement, Radial Distribution System

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B. Chandra Sekhar ¹, Sanjay Lakshminarayanan ²

Affiliations
1 Energy Efficiency and Renewable Energy Division, Central Power Research Institute, Bangalore- 560080, IN
2 Associate Professor, EEE Department, MS Ramaiah University of Applied Sciences (MSRUAS), Bangalore-560054, IN

Abstract

In this study, an integrated double input DC to DC buck-buck boost converter for high/low voltage energy source applications is presented. An integrated buck-buck boost converter which can step down or step up the input voltage according to output voltage required at the load end. A multi input converter can be used instead of single input converters to integrate different energy sources such as solar PV, wind energy system, fuel cell and diesel etc. The converter is designed considering double input, in which same or different type of two inputs can be used individually or simultaneously. The operation modes and the steady state analysis of the converter are delinated. Finally converter behavior observed by using Matlab/SimulinkTM enviornment for closed loop simulation with PI control scheme, the obatinaed results are presented in detailed manner

Keywords

Multi Input DC-DC converters (MICs), hybrid energy system, closed loop control

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G. Ravindra ¹, C. H. Chengaiah ², B. Chandra Sekhar ³

Affiliations
1 Research Scholar, Department of Electrical & Electronics Engineering, S V U College of Engineering, Tirupati - 517502, Andra Pradesh, IN
2 Associate Professor, Department of Electrical & Electronics, Engineering, S V U College of Engineering, Tirupati - 517502, Andra Pradesh, IN
3 Energy Efficiency and Renewable Energy Division, Central Power Research Institute, Bangalore - 560080, IN

Abstract

This paper introduces an integrated energy storage and reactive power compensation in a large wind power plant, and it deals to regulate the reactive power supplied by a variable-speed Wind Energy Conversion System (WECS), based on an induction generator fed by a Matrix Converter (MC). The control strategy used in this paper is input current observer, implemented using an estimation of the modulation index, and a nonlinear control loop that regulates the displacement angle at the matrix converter input. This paper is described the implemention of the matrix converter to control the reactive power by using the Space Vector Pulse Width Modulation (SVPWM) technique in large wind farms and combining them into one system to maintain stability control of the wind power plant. Control of reactive power increases the regulating capacity, which can provide voltage stability in the wind farm. In this work, Matlab/Simulink^TM model and simulation of the three phase matrix converter have been performed using the space vector control algorithm. The algorithm uses a simpler method than the other control algorithms to control the input power factor. To verify the performance of the proposed Matrix Converter, modulation strategy, and control design methodology, various simulation results are presented.

Keywords

Wind Energy Conversion System (WECS), reactive power, Matrix Converter (MC), modulation index, induction generator, input current observer, SVPWM.

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Manohar Potli ¹, B. Chandra Sekhar ², J. C. Balachandra ¹, Y. Babu Yadav ¹, V. Sekhar ¹

Affiliations
1 Assistant Professors, EEE, KEC, Kuppam - 517425, Andra Pradesh, IN
2 Energy Efficiency and Renewable Energy Division, Central Power Research Institute, Bangalore - 560080, IN

Abstract

Renewable energy resources like wind, solar, biomass, tidal, hydropower and geothermal constitute a type of power generation and received much attention as alternatives for conventional power generation. Renewable Energy Resources (RER) will help to mitigate the emission of greenhouse gases. In this paper, a study on reliability constrained optimization of Small Autonomous Hybrid Power System (SAHPS) is carried out. It consists of the 10 kW wind unit, 5 kW solar unit, 5 kW pico-hydro unit and 20 kW diesel unit. Hourly speed of wind, solar radiation and water discharge and load profile is obtained using data synthesizer. The objective function with cost and the number of units and reliability constraint is formulated. Cost minimization and optimal sizing of SAHPS is performed using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). Later markov models for the wind, solar, pico-hydro and load profile with transitions among all states are developed. Markov models are integrated with GA and PSO techniques to minimize the total cost and get the best combination of generation units. All the above analysis is carried out in the MATLAB^TM software environment. Results for chronological method and markov method will be presented and analyzed.

Keywords

Renewable Energy Resources (RER), optimization, data synthesizer and markov models

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