ELECTRICAL ENGG. Volume:92 2011 SEP

Srl	PDF	ARTICLE NAME	ABSTRACT
1		Emission Constrained Optimal Power Flow using Binary and Real Coded Genetic Algorithms	Optimal Power Flow leads to reduction of generation cost, system loss, improved voltage profile, reduction in line and equipment loadings and increased power transfer capability subjected to usual equality and inequality constraints. Due to increased awareness about pollution level, reducing atmospheric pollution levels cannot be ignored.Hence the present paper aims at solving Emission Constrained Optimal Power Flow. Genetic Algorithms gaining lot of popularity in solving power system optimization problems. In view of this both Binary Coded Genetic Algorithm and Real Coded Genetic Algorithm have been applied to solve the Emission Constrained Optimal Power Flow. IEEE 14 and IEEE 30 Bus test systems have been considered to demonstrate the effectiveness of the algorithms.
2		Integrated Electronic Load Controller for Power Quality Improvement of Isolated Asynchronous Generator in Small-Hydro Power Generation	This paper presents an implementation of an integrated electronic load controller (IELC) for regulating the voltage and frequency of an isolated asynchronous generator (IAG) that can supply electricity in remote areas. The IELC is combination of VSC with a dc link capacitor, a chopper and an auxiliary load at its dc bus.It regulates active and reactive powers of the small hydro plant thus regulating the voltage and frequency of IAG system. Beside the voltage and frequency control of IAG, the IELC balances the IAG system under unbalanced loading conditions and eliminates the harmonics of the loads thereby acting both as a load balancer and a harmonic eliminator. The zigzag/star transformer optimizes the dc bus voltage and acts as a neutral current compensator. The proposed IAG along with its IELC is implemented on a 3.7kW IAG system using a DSP.
3		Modelling, Design and Optimization of PI Controller Parameters – Continuous and Discrete Data Approach	This paper presents a systematic procedure for the optimum design of PI controller parameters using empirical and GA based tuning methods. The controllers are designed for a continuous data system taking an example of dc link voltage control loop. For real time implementation of the control (through micro controllers/microprocessor), input parameters are sampled at a frequent interval, it makes the system discrete in nature.Hence PI controller parameters are also designed using discrete data approach. Paper also describes the development of linear mathematical model of the system by applying small signal perturbation technique.
4		Optimal Reliability Planning of an Electrical Distribution System using Differential Evolution	Customer oriented and energy based reliability indices are evaluated for assessing reliability performance of distribution systems. Some important indices are SAIFI, SAIDI, CAIDI and AENS. In turn these indices are functions of failure rate and average repair time of each segment of distribution system.A methodology has been developed in this paper for optimum determination of failure rates and repair times using a population base optimization technique known as differential evolution (DE) accounting constraints on these indices. The algorithm has been implemented on a sample radial distribution system.
5		Pricing System Security in Deregulated Market Including Voltage Stability Constraint	This paper proposes a pricing system for power system security in deregulated market, which includes voltage stability constraint (VSC). The VSC is included in a multi-objective optimal power flow (OPF) that maximizes the social benefit. Ancillary service (reactive power) and system congestion has been considered in the pricing. Effect of N-1 contingency on pricing is also analyzed. Pricing is decided one day ahead using forecasted demand data. The OPF is solved by linear programming method. The system is divided into three areas for which total transfer capacity (TTC) is calculated by repeated power flow technique.The available transfer capacity decides the amount of congestion that affects the pricing. The voltage stability is ascertained by checking the singularity of the system Jacobian matrix. Finally, effect of line/generator loss on pricing system is studied. The model is tested on modified IEEE 14-bus and 30-bus systems and is implemented using MATLAB programming.