Vipul N. Rajput

To handle the challenges attributed to the distributed generators, the protection system of distribution networks needs to be evolved. Recent protection schemes modify the standard characteristics of overcurrent relays, called non‐standard characteristics. These non‐standard characteristics are mostly case‐dependent and have limitations in solving the variety of protection challenges attributed to distributed generators. This paper analyses the performance of six voltage‐based non‐standard characteristics on photovoltaic distributed generators (PVDG) penetrated 3‐bus, 8‐bus, and IEEE 30‐bus distribution grid, as well as the 9‐bus Canadian radial distribution grid with synchronous distributed generator, wind turbine generator, and PVDG penetrations. Besides that, the optimum coordination of these non‐standard characteristics‐based overcurrent relays is a complex problem due to the involvement of additional controlling parameters. To find the best suitable method, a comparative analysis of the genetic algorithm, differential evolution, artificial bee colony, harmony search algorithm, firefly algorithm, cuckoo search algorithm and particle swarm optimization are performed for optimum relay coordination. The outcomes of the paper are thoroughly discussed for future research on non‐standard characteristics development.

The coordination of a large number of protective relays in an interconnected power system is a crucial task. In recent years, researchers have adopted various approaches to attain minimal discrimination time between primary and backup relay pairs for directional overcurrent relay coordination. Researchers have suggested various objective functions to overcome relay mis-coordination and to achieve optimum value of relay plug setting and time multiplier settings. This paper discusses an approach to improve the mathematical formulation for the coordination of directional overcurrent relay for an interconnected power system. Various objective functions reported in the literature are compared with the proposed objective function precisely adopting the overcurrent relay coordination philosophy. To check & analyze the robustness and suitability of the proposed objective function, a modified IEEE14-bus distribution system & IEEE 30-bus system, and IEEE8- bus system is employed. A comparative analysis of the proposed objective function and reported objective functions is presented.

India's power sector is almost going to reach maturity due to some significant recent improvements, including reduced power outages, stable frequency operations, improvement in voltage regulation, initiation of advanced metering installation, and growing renewable resources. However, due to the centralized generation, the power grid of India is still suffering from high transmission and distribution losses, deficiency in fuel supply, electricity theft, unbundling tariff structure, lack of real-time control of the grid and advanced infrastructure of the metering, lack of concrete energy policies, etc. These challenges need to be addressed immediately by the effective deployment of the smart grid in India. This chapter presents the scenario of these challenges for the Indian grid introduced while adopting the smart grid. First, the current scenario and critical issues associated with the grid of India are explained. Subsequently, various aspects and policies for the implementation of the smart grid are discussed. Finally, the enablers and barriers affecting India's smart grid's rapid evolution are identified and discussed hypothetically. The chapter also aims to provide a notable indicative assessment of the factors associated with the smart gird of India, which can be supportive to practitioners, researchers, and engineers involved in the smart grid deployment in India.

This paper introduces a new protection system for solar photovoltaic generator (SPVG)-connected networks. The system is a combination of voltage-restrained overcurrent relays (VROCRs) and directional overcurrent relays (DOCRs). The DOCRs are implemented to sense high fault current on the grid side, and VROCRs are deployed to sense low fault current supplied by the SPVG. Furthermore, a novel challenge for the optimal coordination of DOCRs-DOCRs and DOCRs-VROCRs is formulated. Due to the inclusion of additional constraints of VROCR, the relay coordination problem becomes more complicated. To solve this complex problem, a hybrid Harmony Search Algorithm-Bollinger Bands (HSA-BB) method is proposed. Also, the lower and upper bands in BB are dynamically adjusted with the generation number to assist the HSA in the exploration and exploitation stages. The proposed method is implemented on three different SPVG-connected networks. To exhibit the effectiveness of the proposed method, the obtained results are compared with the genetic algorithm (GA), particle swarm optimization (PSO), cuckoo search algorithm (CSA), HSA and hybrid GA-nonlinear programming (GA-NLP) method. Also, the superiority of the proposed method is evaluated using descriptive and nonparametric statistical tests.