i-manager's Journal on Power Systems Engineering (JPS)


Volume 2 Issue 4 November - January 2015

Research Paper

Mitigation of Unbalanced Voltage Sag/Swells Using Dynamic Voltage Restorer Based on Super Capacitor

K. Venkateswarlu* , B. Ashwin Kumar**, N. Srinivas***, V. Mallikarjuna Rao****
* Associate Professor, Department of EEE, Sri Indu College of Engineering & Technology, Hyderabad, India.
** Assistant Professor, Department of EEE, Sri Indu College of Engineering & Technology, Hyderabad, India.
*** Assistant Professor, Department of EEE, Vardhaman College of Engineering, Hyderabad, India.
**** Sr. Designing Engineer of Electrical Switch Yards SSIPCPL, Hyderabad, India.
Koppolu, V., Kumar, B. A., Srinivas, N., and Rao, V. M. (2015). Mitigation of Unbalanced Voltage Sag/Swells Using Dynamic Voltage Restorer Based on Super Capacitor. i-manager’s Journal on Power Systems Engineering, 2(4), 1-6. https://doi.org/10.26634/jps.2.4.3110

Abstract

This paper presents the design and operation of three phase four wire Dynamic Voltage Restorer (DVR) based on supercapcitor as energy storage to compensate voltage sag/swell in electrical distribution system. The proposed system comprises of power circuit of the DVR, Voltage source inverter and supercapcitor as an energy storage device. It involves the control strategy for the operation of DVR during disturbances in the supply voltage. Control scheme is designed using SRF theory coupled to Proportional Integral (PI) controller technique which is applied to the DVR. The operation of the DVR depends on the control circuit topologies. The main aims of this paper is to design, operate DVR power circuit using SRF and PI techniques to mitigate unbalanced voltage sag/swells in three phase four wire Electrical distribution system. This paper is competent to mitigate voltage disturbances even at low voltage distribution system. The execution of supercapcitor as energy storage is to render real power to the inverter throughout malfunctioning in the supply voltage. The proposed controller was then simulated and outputs were carried out using MATLAB/SIMULINK software.

Research Paper

Multi-Objective Optimized Loadability Estimation by considering Power System Objectives using NSPSO

CHINTALAPUDI* , Sivanagaraju Sirigiri**
* Ph.D Scholar, Department of Electrical & Electronics Engineering, UCEK, JNTU Kakinada, A.P., India.
** Professor, Department of Electrical & Electronics Engineering, UCEK, JNTU Kakinada, A.P., India.
Suresh, V. C., and Sivanagaraju, S. (2015). Multi-Objective Optimized Loadability Estimation by considering Power System Objectives using NSPSO. i-manager’s Journal on Power Systems Engineering, 2(4), 7-20. https://doi.org/10.26634/jps.2.4.3111

Abstract

In Electrical Power Systems operation and management, simultaneous controlling of economic dispatch, emission, electrical power loss and voltage stability index, etc. can be formulated as a multi-objective optimization problem subject to the equality and inequality constraints. Development of an optimal strategy to achieve the above mentioned objectives, while maximizing the quantity of the load, is rather a difficult task. In practice finding a global solution for this type of problem is a matter of sheer diligence and expertise. A modern evolutionary algorithm namely Nondominated Sorting is adapted to Particle Swarm Optimization to solve multi-objective optimization problem. Since the nature of objective functions is not the same, a fuzzy decision making tool is used to choose the best solution. In common practice, maximizing load on a system needs sacrificing of some other objectives simultaneously. So, the main aim of this paper is to find maximum loadability on a given system without enormous violation of other objectives while satisfying the constraints. The efficiency of the proposed approach is examined on IEEE-30 bus with supporting results.

Research Paper

Optimal Distributed Generation Placement for Maximum Loss Reduction using Teaching Learning Based Optimization through Matlab GUI

M.Harini* , M. Damodar Reddy**
* Student, EEE Department, SV University College of Engineering, Andhra Pradesh, India.
** Professor, EEE Department, SV University College of Engineering, Andhra Pradesh, India.
Harini, M., and Reddy, M. D. (2015). Optimal Distributed Generation Placement For Maximum Loss Reduction Using Teaching Learning Based Optimization Through Matlab Gui. i-manager’s Journal on Power Systems Engineering, 2(4), 21-28. https://doi.org/10.26634/jps.2.4.3112

Abstract

In distribution systems, distributed generation (DG) plays a vital role in meeting the demands of electrical energy. It is a small and self generating plant which provides power to industries and homes by improving the voltage profile, stability and by reducing the system losses. Optimal location and sizing of distributed generation in a radial distribution network is an optimization problem with both discrete and continuous variables. This paper presents a fuzzy approach for finding optimal locations and Teaching Learning Based Optimization (TLBO) technique for finding optimal DG sizes. The main objective is to reduce the system power losses and improve the voltage profile of the distribution network. The TLBO is inspired by the influence of the teaching by the teacher on the students in a class. In this paper, GUI is developed in Matlab to perform load flow and to obtain optimal location and sizing of DG. The proposed method was tested on IEEE 15 bus, 33 bus and 69 bus systems and the results were discussed.

Research Paper

Power Quality Improving Using a SPWM Voltage Source Converter

Salla Durga Prasad* , R.S Ravi Sankar**, K. Sravan Kumar***
*PG Scholar, Department of Electrical and Electronics Engineering, Vignan Institute of Information Technology, Visakhapatnam, A.P, India..
**Associate Professor, Department of Electrical and Electronics Engineering, Vignan Institute of Information Technology, Visakhapatnam, A.P, India..
*** Assistant Professor, Department of Electrical and Electronics Engineering, Vignan Institute of Information Technology, Visakhapatnam, A.P, India.
Prasad, S. D., Sankar, R. R., and Kumar, K. S. (2015).Power Quality Improving Using a SPWM Voltage Source Converter. i-manager’s Journal on Power Systems Engineering, 2(4), 29-34. https://doi.org/10.26634/jps.2.4.3113

Abstract

Custom Power is the application of power electronics to improve the quality of power distribution for sensitive industrial plants. Industries reporting production stops due to voltage disturbances, like short interruptions and voltage dips. Power electronics converters connected in series or shunt with the grid and equipped with energy storage can provide protection against voltage disturbances. This work focuses on the voltage source converter (VSC) connected in series with the grid for mitigation of voltage dips as well as swell. The core of this work is the dual vector current controller provide the error voltage. By using the pulse width modulation (PWM) we will generate the switching pulses to the voltage source converter which provide the mitigation for sag and swell. The controller consists of two loops as name as voltage control and vector current control loop. In this work PWM is used. Controllable series compensation is used for power quality improvement under sag and swell.

Review Paper

Applications of Artificial Neural Networks in various areas of Power System; A Review

Manjula S. Sureban* , Shekhappa G. Ankaliki **
* P.G. Scholar, Department of Electrical and Electronics Engineering, SDM College of Engineering & Tech, Dharwad, India.
** Professor, Department of Electrical and Electronics Engineering, SDM College of Engineering & Tech, Dharwad, India.
Sureban, M. S., and Ankaliki, G. S.(2015). Applications of Artificial Neural Networks In Various Areas of Power System; A Review. i-manager’s Journal on Power Systems Engineering, 2(4), 35-44. https://doi.org/10.26634/jps.2.4.3114

Abstract

The Indian power sector has made remarkable progress since Independence. The total installed capacity has gone up from 1,362 MW in 1947 to more than 2,00,000 MW in 2012 and the transmission network has increased from the isolated system concentrated around urban and industrial areas to country wide National Grid. Increased interconnection and loading of the power system along with deregulated structure and environmental concerns has brought new challenges for electric power system operation, control and automation. In liberalized electricity market, the operation and control of power system become complex due to complexity in modeling and uncertainties. In competitive electricity market along with automation, artificial intelligent techniques are very useful. Intelligent techniques make the power system more efficient and effective by operating in the desired manner as per the design and training of the systems. This paper is a review of the applications of Artificial Neural Networks into various areas of power system.