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In recent times, the virtual power plant (VPP) is gaining more attention in power system engineering due to its tremendous potential in enhancing sustainable urbanism, in which, it supplies clean energy from distributed generators. Electricity is deemed a basic requirement for future automotive and ultra-modern technologies. The deficiency of traditional energy resources and their complex generation process make the production cost of electricity increase dramatically. Moreover, traditional power distribution systems are encountering issues in distributing electrical energy to fulfill customer demands. Therefore, this paper proposes a novel power management system named 'the hybrid genetic local binary knowledge (HGLBK) algorithm' to manage power distribution in the transmission lines and to optimize the total operation cost of the network. The hybrid optimization algorithm effectively controls the load by supplying the surplus power load to the adjacent feeders thereby optimally selecting and placing the distributed energy resource (DER). The proposed concept is implemented at Kayathar, Tamil Nadu in India, and their real-time data are utilized for modeling the VPP. The proposed VPP concept is implemented in the IEEE-9 bus system and the performance of VPP is simulated using the MATLAB software. The performance of the proposed HGLBK algorithm is assessed by comparing its effectiveness with the existing approaches. [ABSTRACT FROM AUTHOR]

Reliable energy is ensured by the power quality, safety and security. For reliability and economic growth of transmission utilities, it is necessary to maintain continuity of supply, which is challenging under deregulated system. It is essential for utilities to conduct regular maintenance of transmission lines before supply interrupts. To protect line from fault, it is necessary to detect fault on line, its classification and location at the earliest. Various smart techniques along with application of artificial intelligence (AI) in power system are under investigation. This paper tries to find solution by identifying practical common faults occurred on transmission lines, and also suggests the suitable maintenance methodology. It uses the artificial neural network (ANN) method and live line maintenance technique (LLMT) for pre identification of a fault and subsequent predictive maintenance. Paper compares results of combination of ANN with LLMT and cold line maintenance technique (CLMT). Comparison of statistical analysis shows combine model of ANN and LLMT results in minimize outage time, failure rate which can improve system availability and increases revenue. [ABSTRACT FROM AUTHOR]

Personal communication methods in underground coal mines are far less sophisticated and efficient than surface level communication techniques. This deficiency can be attributed to the generally unfavourable and hazardous environment prevailing underground which acts as a deterring factor for their development. However, effective and reliable communication between underground coal mines and the control room on the surface is essential for safety and emergency rescue operations. Wireless communication is not a viable alternative because of the high attenuation profile as well as variation in the propagation path through uneven structures of underground coal mines and inflammable gases and moisture generally present there. Hence, wired personal communications using an existing structure such as power lines forms a very efficient and economical approach. This paper investigates the developments of communication in underground coal mines in India and presents an overview of the power line communication (PLC) technology. The possible use of PLC especially for deployment in underground coal mines in India is discussed in detail. [ABSTRACT FROM AUTHOR]

The Environment Impact Assessment (EIA) is a regulatory framework adopted since 1994 in India to evaluate the impact and mitigation measures of projects, however, even after 25 years of adoption, EIAs continue to be of inferior quality with respect to biodiversity documentation and assessment of impacts and their mitigation measures. This questions the credibility of the exercise, as deficient EIAs are habitually used as a basis for project clearances in ecologically sensitive and irreplaceable regions. The authors reiterate this point by analysing impact assessment documents for three projects: the doubling of the National Highway-4A, doubling of the railwayline from Castlerock to Kulem, and laying of a 400-kV transmission line through the Bhagwan Mahavir Wildlife Sanctuary and National Park in the state of Goa. Two of these projects were recently granted 'Wildlife Clearance' during a virtual meeting of the Standing Committee of the National Board of Wildlife (NBWL) without a thorough assessment of the project impacts. Assessment reports for the road and railway expansion were found to be deficient on multiple fronts regarding biodiversity assessment and projected impacts, whereas no impact assessment report was available in the public domain for the 400-kV transmission line project. This paper highlights the biodiversity significance of this protected area complex in the Western Ghats, and highlights the lacunae in biodiversity documentation and inadequacy of mitigation measures in assessment documents for all three diversion projects. The EIA process needs to improve substantially if India is to protect its natural resources and adhere to environmental protection policies and regulations nationally and globally. [ABSTRACT FROM AUTHOR]

The insulation of the power transmission system experiences stresses due to power–frequency voltage under normal operating conditions, temporary overvoltages at or near power–frequency and transient overvoltages arising either from switching operations and faults or from lightning discharges. However, in the insulation design of extra-high-voltage and ultra-high-voltage systems, transient overvoltages arising from switching operations and faults become the controlling factor. Insulation failure probability under switching overvoltages is the main impressive concern in the estimation of switching surge flashover rate. In this paper, a practical method is used to estimate the switching surge flashover rate of insulation under switching overvoltages generated during energization, re-energization, fault initiation and fault clearing of an unloaded transmission line, which considers the variable characteristics of the insulation strength of the transmission line according to the switching overvoltage waveshape. The results focus on the comparison between traditional and practical methods which considers the effect of the front time on the first 1200-kV UHVAC transmission line in India. [ABSTRACT FROM AUTHOR]

Eastern Regional (ER) grid of India is one of the five regional grids consisting of voltage level 765 kV, 400 kV, 220 kV and numerous buses at lower voltage range. ER grid is the backbone of the Indian Grid as it is one of the main power generating hubs. Stability of the Indian Grid depends a lot on ER grid as it is the core of the generation and transmission system. For performing stability studies and to determine the weak area of the grid generally L-Index method is used. For detailed analysis like computation of voltage recovery time, maximum frequency deviation and critical clearing time of the buses of the system L-Index method is not suitable. Hence dynamic simulation is performed as it provides options to compute various parameters of ER Grid. The system has been studied using 197 buses of voltage levels 220 kV and above and transmission lines running over a length of 23,693 km. In this paper the power flow modelling, simulation and analysis of the Eastern Grid of India is performed. L-Index algorithm along with dynamic simulation provides the scope of computation of voltage recovery time, maximum frequency deviation and critical clearing time (by introducing an initial transient disturbance) along with the prediction of weak area of the system which gives a complete picture of transient stability of ER Grid. [ABSTRACT FROM AUTHOR]

This paper presents an effective method of congestion management in power systems. Congestions or overloads in transmission network are alleviated by generation rescheduling and/or load shedding of participating generators and loads. The two conflicting objectives 1) alleviation of overload and 2) minimization of cost of operation are optimized to provide pareto-optimal solutions. A multiobjective particle swarm optimization (MOPSO) method is used to solve this complex nonlinear optimization problem. A realistic frequency and voltage dependent load flow method which considers the voltage and frequency dependence of loads and generator regulation characteristics is used to solve this problem. The proposed algorithm is tested on IEEE 30-bus system, IEEE 118-bus system, and Northern Region Electricity Board, India (NREB) 390-bus system with smooth as well as nonsmooth cost functions due to valve point loading effect. [ABSTRACT FROM AUTHOR]

Megawatt (MW) power flow tracing can assess the extent of network usage by the participants that can be effectively used for multiple objectives like transmission pricing, loss allocation, etc. MW power tracing, a post-facto analysis of power flow solution, is amenable to multiple solutions. This implies multiplicity of solution space of transmission cost and loss allocation problems. The conventional tracing methods enforce a ‘proportionate sharing rule’ to calculate the shares. These shares are sensitive to quantity and distance as against the postage stamp method, which is immune to distance. Any of these methods will result in penalizing a set of constituents, which raises a fairness issue. This is evident from the experiences of developing countries like India. In this paper, a new paradigm is suggested that attempts to capture the best of the two methodologies by exploring multiplicity of the solution space of the tracing problem, within the given constraints. We show that the tracing problem can be formulated as a linear constrained optimization problem. We propose a tracing compliant modified postage stamp allocation method that computes a traceable solution that minimizes overall deviation from the postage stamp allocation. Results on actual data of central transmission utility of Western Regional Grid of India demonstrate the claims. [ABSTRACT FROM AUTHOR]

In India, apart from state owned generators, a central sector power pool has been created consisting of central sector power stations. The Central Transmission Utility (CTU) has built an EHV network to transfer this power to the constituents of the regional network. To recover the costs incurred, the CTU levies the Transmission Service Charges (TSC) over the constituents. The constituents are billed for network usage charges which are proportional to their allocated share in the central sector power generation. An ideal pricing mechanism would have been to find out the usage of the network by the constituents and charge accordingly. In this paper, a real power tracing based method for recovery of Transmission Service Charge (TSC) from the constituents of Western regional grid in India is proposed. The method uses proportionality based real power tracing to find out the network usage by various constituents. Loss allocation on EHV network to the various constituents is also done. Actual data of power flows over the EHV network of Western regional grid for one day is considered. [ABSTRACT FROM AUTHOR]

Smart grids are the future of Indian power sector and would go a long way in reducing environmental impact and tackling the major challenges faced like technical and commercial losses, chronic supply-demand gap and frequent blackouts. Transforming the existing electric infrastructure through a smart grid is the way forward to ensure efficient and reliable power supply, and achieve sustainable development. The Government of India has identified and initiated a number of remarkable steps towards a more reliable, resilient, cost-effective and interactive power grid. This paper aims at providing a detailed view of the background and current status of the major smart grid initiatives and projects in India, along with a few suggestions for the successful way ahead. [ABSTRACT FROM AUTHOR]

The National Electricity Policy (NEP) [], issued by the Government of India, mandates transmission prices to be distance and direction sensitive and capture utilization of the network by each network user. In line with the mandate, the Central Electricity Regulatory Commission (CERC) [] has issued Sharing of Interstate Transmission Charges and Losses Regulations, 2010 [], to introduce point of connection (PoC)-based transmission pricing methodology in India. The methodology under the above regulations introduces one of the major reforms of its kind in the Indian power sector and seeks to share the total transmission charges in proportion to respective utilization of the transmission system by different entities. In this paper, the authors have enumerated their experience gained from the implementation of PoC-based transmission pricing regime in India. Authors have also discussed various issues encountered in the process of implementation and the methodology adopted. [ABSTRACT FROM AUTHOR]

The electrical transmission infrastructure worldwide has witnessed severe environmental hazards, accidents and in countries like Columbia and India malicious attacks leading to the sabotage of transmission towers. These events underscore the need to develop new techniques to ensure safe and reliable operation of the transmission infrastructure. This paper deals with an online monitoring technique based on mechanical state estimation of overhead transmission lines subjected to tower tilt. The proposed approach provides a quick assessment of the grid condition at the initial stages of an extreme mechanical event. A computational algorithm based on least squares state estimation is applied to transmission line sag-tension equations developed through a geometric transformation to determine conductor sag levels. The measurements of tower tilt, conductor tension, core temperature, inclination angle of conductor with the horizontal and other transmission line parameters are utilized for the purpose of state estimation. Appropriate warning alarms generated in the case of considerable changes in the sag levels or violation of limits enable operators to take designated actions during the initial stages of the physical disruption. [ABSTRACT FROM AUTHOR]

The need of higher bandwidth systems has led the system designer to shift into higher frequency region. But working at these high frequency regions is not that easy. The paper presents results of the measurements of rain induced attenuation of a LOS link operating at 28.75 GHz at Amritsar (31°36′ N 74° 52′ E) for a single event that occurred on the 15th Nov., 2004. The results have been compared with those of ITU-R Model. It is observed that there is a significant difference between the attenuation levels measured and those predicted by using ITU-R model. [ABSTRACT FROM AUTHOR]

At present the Indian Power Sector is seriously considering the optimization of their existing inter-regional transmission links, and also planning to form new inter-regional links. As one of the options, Thyristors Controlled Series Compensation (TCSC) scheme has been implemented recently in the Uttar Pradesh State, in the 400 kV links between Anpara and Unnao, and further efforts have not been made yet. At this stage, as a helping hand to the Power Sector in its decision-making, this paper explores the need for further transmission system upgrading, and based on a prototype transmission system study, it identifies a few more inter-regional transmission links for TCSC implementation. [ABSTRACT FROM AUTHOR]

Previously, it was found that the analytical deflections computed for towers using computer software are less than those from test results. The present study is aimed at deriving a relationship between the ratio of the test to theoretical deflection, and a nondimensional parameter to serve as an index for monitoring the structural displacements during testing. Currently, structural dynamic evaluation plays little or no role in the design of towers, partly due to the difficulties involved in the analysis and the relatively high cost of field testing. Using the fundamental frequency of a tower, the peak response of the tower to gusty wind and the impact force caused by conductor breakage can be evaluated. Both theoretical and experimental studies have been carried out to evaluate the natural frequencies of the towers tested at TTRS, SERC, Chennai, India. Based on these data, an equation was derived in this paper using the tower geometry and test/theoretical deflection ratios, which allows us to predict the natural frequency of the tower in a way closer to its actual value. [ABSTRACT FROM AUTHOR]

Conventional load flow algorithms are very commonly used in the system planning. In the conventional load flow methods, system electrical parameters at specific weather conditions will be considered. These methods gives results for given loading condition and have no provision to incorporate weather condition of a specific geographical location. If the load flow has the provision to incorporate the dynamic electrical characteristics of the conductors based on the operating weather condition, the results of the methods are going to be more accurate or in other words the results are close to the real values. In view of the above, in this paper a modified load flow algorithm incorporating the thermal modeling of the conductors with ambient temperature, wind velocity, conductor surface absorptivity, global solar radiation, Wind direction factor etc. is proposed. To verify the effectiveness of the proposed algorithm, the thermal mathematical model of transmission lines available in IEEE Std. 738™ -2006, IEEE Std. 738™ -2012 and CIGRE WG 22.12 are considered. In the proposed algorithm, new variables corresponding to Conductor Temperature are incorporated. The proposed algorithm is tested with the real time weather data of India and demonstrated on IEEE 30 and 118 bus systems. • An algorithm for power flow including thermal models of the transmission lines. • Variable weather and ZIP load models are incorporated in the proposed algorithm. • It estimates the transmission line temperature using the field measurements. • Seasonal variations of the critical bus voltages are estimated using proposed method. • Impact of renewable generation on system performance is evaluated. [ABSTRACT FROM AUTHOR]

A hybrid scheme for transmission line protection (HSTLP) using the Stockwell transform (ST), Wigner distribution function (WDF), and alienation coefficient (ACF) is designed. Current signals are analyzed using the ST, WDF, and ACF to compute the Stockwell fault index (SFI), Wigner fault index (WFI), and alienation coefficient fault index (ACFI), respectively. These fault indexes are used to derive a hybrid signal processing fault index (HSPFI), which is implemented for the detection of transmission line fault events. The peak magnitude of HSPFI is compared with a preset threshold magnitude (TH) to identify the fault. The statistical formulation is proposed for fault location on the power transmission line. Fault classification is achieved using the number of faulty phases. A hybrid ground fault index (HGFI) is used to recognize the involvement of the ground during the fault event. This HGFI is determined by processing zero sequence current using ST and WDF. The performance of algorithm is tested by various case studies for fault impedance variation, variable sampling frequency, fault incidence angle variation, reverse power flow on transmission line, highly loaded line, different fault locations online, and noisy conditions. The algorithm is also validated to detect a fault on a practical transmission line of large area utility grid of Rajasthan Rajya Vidyut Prasaran Nigam Limited (RVPN) in India. The algorithm performs better than the Hilbert–Huang transform (HHT)-based protection scheme and wavelet transform (WT)-based protection scheme available in the literature in terms of mean error of fault location, fault location accuracy, and noise level. The proposed protection scheme efficiently detected, classified, and located the faulty events such as single-phase-to-ground fault (SPGF), two-phase fault (TPF), two-phase-to-ground fault (TPGF), three-line fault (TLF), and three-line-to-ground fault (TLGF). Transmission line fault location accuracy of 99.031% is achieved. The algorithm performs well even with a high noise level of 10 dB SNR. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents different types of premature failures observed during full-scale testing of Transmission line towers at Tower Testing and Research Station, Structural Engineering Research Centre, Chennai. Failures that have been observed during testing are studied and the reasons are discussed in detail. The effect of non-triangulated hip bracing pattern and isolated hip bracings connected to elevation redundants in ‘K’ and ‘X’ braced panels, on tower behaviour are studied. The tower members are modeled using beam-column and plate elements. Different types of failures are modeled using finite element software and the analytical results and the test results are compared with various codal provisions. The non-linear finite element analysis program NE-NASTRAN has been used to model the elasto-plastic behaviour of towers. Importance of secondary member design and connection detail in overall performance of the tower was studied. Non-linear finite element analysis is useful in understanding the system behaviour and for prediction of failure pattern and ultimate load. Based on the test results the importance of studying the failures is highlighted. The need for testing of transmission line towers is emphasized. [Copyright &y& Elsevier]

The article argues that as India and Bhutan have moved into the second phase of power cooperation, it is important that the two countries revisit their policies and identify approaches that will be sustainable in the long term. The article emphasises that a sub-regional energy grid between Bhutan, India and Bangladesh can become an effective conduit for strengthening sub-regional diplomacy and help in addressing the latent but underlying concerns of Bhutan, which have the potential to impact India–Bhutan bilateral relations in the long term. [ABSTRACT FROM AUTHOR]

The development of a new differential protection scheme for tapped transmission lines using wavelet transform is presented. At each relay locations, using the most suitable mother wavelet, the measured three line currents are decomposed up to third level. Thereafter, third-level approximation coefficients are reconstructed and used to derive the operating and restraining quantities. The proposed scheme has been tested extensively using the PSCAD/EMTDC software package with fault data, generated by modelling UKAI-KAKRAPAR 400 kV line of the Indian power system. The proposed scheme eliminates many of the problems encountered with tapped transmission lines such as high resistance faults, outfeed current in case of internal and external faults, insufficient current for tripping and provides better discrimination between external and internal faults in case of loss of generation at one end. At the end, a comparative evaluation of the conventional current differential protection scheme with the proposed scheme is also presented. Dependability and security have been studied separately. [ABSTRACT FROM AUTHOR]