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This paper presents a new fast Intelligent Programmed Genetic Algorithm (IPGA) based evolutionary optimization algorithm which requires lesser number of objective function evaluation for reaching optima. The proposed algorithm, apart from using probabilistic genetic operator, i.e. crossover and mutation, also uses a deterministic diversity creating operator for generating new solution in the current population. This is done by first projecting objective surface from higher dimension to lower dimension for visualization purpose and then deterministically generates new solution using some predefined rules in the region with higher objective function value. As the newly generated solution is in lower-dimensional space, these solutions are again projected back to higher dimensional space and then the objective function is evaluated at that point. The proposed IPGA is tested on three different categories of standard test functions viz. Unimodal function (2 Test Function), Unrotated Multimodal function (6 Test Function) and Rotated Multimodal function (5 Test Function). Simulation results were compared with that obtained using Binary Coded GA, Real Coded GA, recently proposed GA with Differential Evolution crossover operator (GA–DEx) and another success-history-based adaptive GA with aging mechanism (GA–aDExSPS) in terms of mean and standard deviation of the objective function, average number of objective function evaluation required to reach optima and algorithmic complexity. Simulation results clearly demonstrate better performance of the proposed IPGA when compared with other variants of GAs.

Voltage stability is a relevant part of power system stability analysis ever since many voltage collapse incidences have occurred at different regions of the world. In this paper we take up IEEE 118 bus system as it represents a close approximation of standard Grid system. This IEEE 118-bus system has fixed number of predefined generators, synchronous condensers, transmission lines, transformers and loads. In this work IEEE 118 bus system is simulated and load flow simulation is computed using the software PSS®E. The weak buses of the IEEE standard 118 bus network are predicted with the help of L-Index Algorithm in MATLAB. Further dynamic simulation is also performed in the weak buses obtained from L-Index as it opens up scope of more detail analysis of the system. An initial transient disturbance is then introduced in the weak buses and then the resultant maximum frequency deviation and the recovery time of the voltage is computed which finally helps to detect the weak areas in the transmission network. Further Critical Clearing time of the weakest bus is also computed.

Energy policymakers address rural energy poverty with locally available renewable sources. Further, an acquaintance in the adoption of similar renewable based rural electrification technology (RBRET) would enhance the community acceptance in the neighboring villages. As a result of which, the pace of RBRET dissemination can be heightened in the corresponding geographic cluster. Amongst the varied RBRET projects, Micro Hydro Power (MHP) is relatively economic, efficient, reliable, and ease to operate. However, the sustainability of MHP cluster relies upon the appropriate prioritization process of site selection. In this regard, a novel computational intelligence technique has been proposed through a case study in the eastern Himalayan region of India. The proposed model encompasses four phases. First, refinement of the initial technical feasibility conformations through geographical information system (GIS) and past hydrological data. Second, the establishment of interdependency influencing relationship using interpretive ranking process (IRP). Third, the computation of Pareto based prioritization of entropy weights derived through IRP. Fourth, the prioritization of potential sites for MHP in the sequential manner adopting fuzzy similarity analysis measure, and Ardalan heuristic method. The proposed hybrid model surpasses the existing application of standalone methods such as multi-criterion analysis tools, geographic information system, and econometric analysis method.

The Unified Power Flow Controller (UPFC) is the adjustable flexible ac transmission system (FACTS) controller that can control the three parameters i.e. Impedance, Voltage and Phase angle of transmission line simultaneously or individually in appropriate combination. This paper presents an investigation on the current research and on the application of fuzzy logic controller in Unified Power Flow Controller (UPFC). A comparative study is also carried out which highlight the different aspects of control strategy of UPFC.

This work presents a novel stator flux-oriented vector control (SFOVC) of a dual stator induction generator (DSIG) used for a grid connected, variable speed wind energy generation system. The DSIG consists of two stator windings electrically separated by an angle of 30° with dissimilar pole numbers, which are in the ratio of 1:3. In conventional vector control, the rotor flux is oriented along the d-axis of the rotor winding. However, the rotor variables are not easily accessible. So, in the SFOVC, the total flux is made to be oriented along the d-axis of the stator winding. SFOVC is advantageous as compared to conventional vector control because the stator variables are easily accessible and do not require any special arrangement for the measurement of variables which increases the robustness of the system. Here, two separate converters are used for the two stator windings of the machine and the converter switching is being controlled by a novel space vector based 11-zone hybrid pulse-width modulation (PWM). This special PWM results in better harmonic performance, reduced torque pulsation and minimal switching loss. The overall simulation is being performed in MATLAB Simulink environment and the simulated results are also being validated experimentally.

In this paper a novel speed sensor less vector control of Dual Stator Induction machine has been proposed for grid connected wind energy generation system. Dual Stator Induction machine consists of two stator winding separated by an electrical angle of 30°, with dissimilar pole to overcome the effect of harmonic current occurred in the stator windings. In this work the pole ratio of the two stator winding are taken as 3:1 in order to mitigate the magnetic saturation of the core and high losses which occurs at stator winding. The orientation of the machine is made in such a way that by controlling two stator currents in a perfectly decoupled way zero speed operation can be made possible. There by electrical frequency of it gets maintained at low speed, this characteristic of stator makes the Dual Stator Induction machine more suitable for speed sensor less operation. The two stator windings of the machine are fed from two independent Variable Voltage Variable Frequency inverter, which is being controlled by advanced bus clamping Pulse Width Modulation Technique. The Pulse Width Modulation proposed in this paper is a 9 zone hybrid PWM which results into lower line current ripple, reduced torque pulsation and minimized switch loss then the conventional space vector pulse width modulation, basic and advanced bus clamping PWM and the existing 3, 5 and 7 zone hybrid pulse width modulation. The simulation is being performed in MATLAB and the simulated results are being verified by experimental results. dSPACE DS-1104 Data Acquisition Card is being used to implement the overall control topology.

This study provides an overview of the different techno-commercial aspects of a wind energy conversion system. The review includes the grid codes provided by the transmission system operator of different countries supplemented by various communication protocols, explanation of different types of conventional and advanced wind generators, discussions on different maximum power point algorithms along with various conventional and advanced pitch angle control systems. The study also describes a variable speed system using different types of power electronic converters at the generator and the grid side to maintain power quality, grid synchronisation and unity power factor operation along with various cooling techniques utilised. In a subsequent part, a clear overview of different control topologies such as field-oriented control, direct torque control, voltage-oriented control and direct power control has been provided along with the recent advancement of each and every topology. The study also provides the challenges of the prevailing technology along with the already available and possible ways of minimising these technological gaps. Finally, a techno-commercial comparison of different commercially available wind systems by different companies has been presented along with their market share based on the current scenario.

Close Proximity Operation of HVAC and HVDC transmission line is the recent trend for increase of power transmission capacity. Need for same is becoming vital day by day due to ever increasing power demand. Erection of HVAC lines has a requirement of high right of way (ROW) as compared to the HVDC lines. Also recent past has witnessed constraint in availability of ROW for many projects of Indian Power Grid. Raise in transmission voltage level of HVDC from Power Grid Corporation of India Limited (PGCIL) and its suitability to decentralized non-conventional grids has led to addition of many upcoming HVDC projects with the already existing ones. So the need of analysis for electric field distribution under this type of hybrid transmission corridor is necessary to meet the standards of engineering design, exposure limits to living beings and environmental protection. The present work shows a two dimensional modelling approach for estimation of hybrid electric field at ground surface with impulse excitation. A practical case of hybrid transmission corridor so formed in Northeast Agra HVDC project of PGCIL has been taken for this case. Effects of both standard and non-standard impulse waveform has been modelled and analysis of its effect on hybrid electric field is presented.

Electric power supplier using thermal generator submits block bid in a Day-Ahead Electricity Market to compensate for high startup and shut down cost. Flexi type Block Bid is a special kind of Block Bid, currently used in Nord Pool, have flexible execution time set by Power Exchange (PX) based on Social Welfare maximization. The optimal placing of block bid execution time is an NP-hard combinatorial optimization problem whose solution is difficult to obtain using repeated application of Mixed Integer Linear Programming algorithm in polynomial time. Therefore this work formulates the optimal placement of suppliers block bid in a Day-Ahead Electricity Market as an optimization problem and solve using Genetic Algorithm. Social welfare for 24 hours of next day called social welfare volume has been used as an objective function to maximize. Computer simulation was performed using MATLAB with hourly electric power demand randomly generated as per the typical hourly power demand curve in Indian power system. Two types of Block Bid are considered for simulation, the first one in which length of the block is fixed and second one in which length of block bid can vary from fixed minimum to fixed maximum. Simulation result clearly shows that there is a significant increase in social welfare volume and hourly Market Clearing Volume and a significant decrease in Hourly Market Clearing Price for both the cases.

The effects of impulse faults of different nature and different locations of occurrence in the high voltage winding of a transformer are investigated in this work. During the investigation, a high frequency transformer model developed in MATLAB Simulink was subjected to different lightning and switching impulse waveforms. Turn-to-earth and turn-to-turn faults were simulated at different locations of the windings due to applied impulse. The transformer response is studied owing to the variation of the input impulse waveforms, fault types and their location along the windings. This study is important in the purview of fault characterization which provides an important basis for developing more reliable and sensitive methods to detect internal faults in the transformer windings.

Bewley's lattice diagram is a graphical method that has been widely used for determining value of a wave in transient analysis. This paper presents an extensive literature survey of previous publications in which Bewley's lattice diagram has been used for study of electromagnetic transients, fault location in distributed systems, calculation of transient fault currents n voltages in power system networks. From the survey, several observations can be made, such as on the purpose of analysis using this method and its advantages over the other methods. The paper also further discusses about the work done for computation with digital computer using spreadsheet and recursive algorithm method. The spreadsheet method is quite difficult to program using a high level language. The later method can be easily done with recursive algorithm and further work needs to be done in this direction.

This paper presents the study of transients resulting from different circuit topology in an isolated power system. The analysed data are obtained from experiments as well as simulated model based on Simulink in Matlab environment. The experimental set up as well as the simulation parameters is discussed along with the viability of the simulation model. The data are analysed using continuous wavelet transform based dominant frequency signature (DFS) and conclusions have been drawn thereafter.