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In this study, a new circuit topology using a Z-source resonant inverter (ZSRI) for high power applications in large-air-gap contactless power transfer (CPT) systems, has been investigated. The main shortcoming of a large-air-gap CPT system is the poor power transfer efficiency due to low magnetic coupling. In order to minimize this shortcoming and to improve the overall performance of the system by boosting the power transfer capability, in this paper a CPT system with the newly developed circuit topology using high frequency Z-source resonant inverter has been proposed. Using the newly developed circuit topology for the CPT system, it has been observed that the overall performance of the system has been improved to a reasonable level with a purely sinusoidal resonant current flowing through the primary side. Therefore, no harmonics will be injected into the source. The proposed CPT system with an air gap of 16 cm and a misalignment of 3 cm has been simulated using the Maxwell finite element tool and Simplorer circuit simulation software for an output power of 2 kW.

Synchronization in the energy generated by renewable energy sources is one of the significant issue associated with the converter used in the system module. The presented paper concentrates on the design aspect of a PV and wind power input to a DC-DC converter which can be practically useful in hybrid renewable energy power systems. In this regard, the proposed converter can be utilized to obtain a smooth regulated output voltage from the given input renewable energy power sources. The proposed converter can be efficiently work under critical conditions having very few ripple in current waveform of input or output. A major advantage with this type of converter is the simple circuit with respect to the conventional converters in some critical situations. At the end, the result based on the simulation exercise and various experiments, performance of the converter in different situations is presented so that the efficiency of the designed converter arrangement is accepted.

A novel circuit topology of modified switched boost high frequency hybrid resonant inverter fitted induction heating equipment is presented in this paper for efficient induction heating. Recently, induction heating technique is becoming very popular for both domestic and industrial purposes because of its high energy efficiency and controllability. Generally in induction heating, a high frequency alternating magnetic field is required to induce the eddy currents in the work piece. High frequency resonant inverters are incorporated in induction heating equipment which produce a high frequency alternating magnetic field surrounding the coil. Previously this high frequency alternating magnetic field was produced by voltage source inverters. But VSIs have several demerits. So, in this paper, a new scheme of modified switched boost high frequency hybrid resonant inverter fitted induction heating equipment has been depicted which enhances the energy efficiency and controllability and the same is validated by PSIM.

Increasing energy demands due to factors such as population, globalization, and industrialization has led to increased challenges for existing energy infrastructure. Efficient ways of energy generation and energy consumption like smart grids and smart homes are implemented to face these challenges with reliable, cheap, and easily available sources of energy. Grid integration of renewable energy and other clean distributed generation is increasing continuously to reduce carbon and other air pollutants emissions. But the integration of distributed energy sources and increase in electric demand enhance instability in the grid. Short-term electrical load forecasting reduces the grid fluctuation and enhances the robustness and power quality of the grid. Electrical load forecasting in advance on the basic historical data modelling plays a crucial role in peak electrical demand control, reinforcement of the grid demand, and generation balancing with cost reduction. But accurate forecasting of electrical data is a very challenging task due to the non-stationary and nonlinearly nature of the data. Machine learning and artificial intelligence have recognized more accurate and reliable load forecasting methods based on historical load data. The purpose of this study is to model the electrical load of Jajpur, Orissa Grid for forecasting of load using regression type machine learning algorithms Gaussian process regression (GPR). The historical electrical data and whether data of Jajpur is taken for modelling and simulation and the data is decided in such a way that the model will be considered to learn the connection among past, current, and future dependent variables, factors, and the relationship among data. Based on this modelling of data the network will be able to forecast the peak load of the electric grid one day ahead. The study is very helpful in grid stability and peak load control management. [ABSTRACT FROM AUTHOR]

A voltage sag is a major power quality problem at any load location, mainly due to short circuit faults. Its effects are especially clear in the industrial sector because they lead to direct financial losses. The first and most important step to getting rid of or at least reducing voltage sag is to find the places in the network where it can happen. So, this article discusses a creative way to find the weak spots in a network where the voltage is more likely to drop. This innovative strategy is based on correlation and a stochastic normal probability distribution. The voltage sag is evaluated using an analytical method. The method simulates the number, type, and location of faults randomly throughout the system. After gathering voltage dip data, it is analyzed using normal probability distribution and correlation concepts. The correlation concept provides the relationship between the sag frequency and other parameters, and the sag occurrence area was indicated by the normal probability distribution. After that, the region of vulnerability (ROV) is developed using the ROV flow chart. This paper uses an IEEE 30-bus RTS system as a case study to demonstrate the usefulness of the suggested strategy using MATLAB software. [ABSTRACT FROM AUTHOR]

In this paper, different mathematical expressions are derived to compute the residual magnitude of voltage caused by faults along the line and on the bus. Symmetrical and unsymmetrical faults are taken into consideration, and the consequences of the various fault distributions are considered. A new way of assessing a sag is proposed that incorporates the method of fault position and mathematical expression based on sequence currents and voltages. The fault impedance is introduced to obtain a better result. A fast and efficient load flow analysis technique produces quick computational results. In addition, the sag analysis is performed using the bivariate joint discrete probability distribution method that gives a clear idea about the probability of occurrence of sag in a meshed network. The suggested approach is applied in the IEEE 39-bus system and with an existing real-time electrical power distribution system in India. [ABSTRACT FROM AUTHOR]

The urban and suburban advancement has increased the consumption of energy per capita gradually. Electrical distribution companies have expanded their network to cater to the demand, making the system more vulnerable to low probability high impact events. The extreme events occurred in last five year had shown us complete to partial blackout, which calls for resiliency enhancement. The presented study concentrates on the Dehradun, India, which listed as the most earthquake-prone region by Union Nations Development Programme. Hence, this paper proposes three main strategies to make a resilient distribution grid against an earthquake; (i) Hardening approach at grid side and demand side against earthquake disaster (ii) Monte-Carlo methodology for earthquake hazard model (iii) K-means algorithm with clustering quality index to identify the multiple vulnerable zones. Grid side hardening is performed using the optimal unit placement of the Solar PV plant (SPP) with storage and parallel cables with sectionalizers. For demand-side hardening, electric vehicles are considered storage after an event, duly taking their future growth rate into account. Furthermore, a Mixed Integer non-linear problem is formulated to identify the optimal sizing and sitting of SPP with storage. The proposed methodology is developed and applied to the distribution system (156-bus) of Dehradun, India. • Resiliency enhancement at grid-side & demand-side using DER and EVs. • Earthquake hazard model is developed using Monte-Carlo methodology. • Identification of optimal number of vulnerable zone with clustering quality index. • A case study on 156 bus mixed-terrain real distribution system of Dehradun, India. [ABSTRACT FROM AUTHOR]

Day by day, the exponential growth in the electricity demand is being seen, while the resources of fossil fuel are decreasing. The limited resources of fossil fuel force the world to use renewable energy. The renewable resources are characterized by a source of clean/green energy, omnipresent, freely available. Even though the renewables have strong potential to meet the future electricity demand; it only contributes approximately 24% to the world electricity generation. India has a strong potential of the possibility of roughly 1001 GW of power generations from renewable energy, but nearly 69 GW of power have been installed presently. This scenario reveals that there is a need for development in renewable technologies. In this direction, India has set the target of 175 GW of power generations from the renewable resources by the year 2022. The addition and expansion of the renewable energies experience some barriers in the present situation. The present article concentrates on the identification and addressing of barriers toward the renewable developments and recommendations proposed to overcome these barriers. The current energy scenario of India and estimated potential and future targets of the renewable energies have also been presented. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Sustainable Development / Problemy Ekorozwoju is the property of Faculty of Environmental Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper represents a comparative analysis of two photovoltaic pumping systems. To study the performance of the Maximum Power Point Tracking (MPPT) system, two models were simulated using Matlab/Simulink and the performance of a directly connected photovoltaic (SPV) pumping system was compared to an MPPT connected SPV pumping system at various levels of solar irradiance. The MPPT system maximizes overall system efficiency, but makes the system complex compared to the directly connected SPV pumping system. Instead of the conventional boost converter the MPPT system contains a buck converter to maintain overall system voltage at the lower levels required by the permanent magnet DC (PMDC) motor. For simplicity, the MPPT controller follows the perturbation and observation (P & O) algorithm and controls the buck converter to maximize overall system efficiency at various levels of solar irradiance. The PMDC motor provides high weight-to-torque density, better speed control, low inertia, and lower losses compared to induction and the conventional DC motor. The comparative analysis shows that the MPPT connected SPV system is more efficient than the directly connected SPV system for water pumping purposes using a PMDC motor. [ABSTRACT FROM AUTHOR]

Efficient contactless power transfer (CPT) is an emerging technology which is attracting great scientific interest because it can mitigate some of the problems commonly associated with conventional wired power transfer systems. CPT systems suffer from very low efficiency because of the poor coupling coefficient, which is due to the large air gap between the transmitter and receiver coils. Therefore, CPT transformers are mostly operated at high frequencies to improve the quality factor of transmitter and receiver coils and thus counterbalance the effect of the low coupling coefficient. On the other hand, informed selection and design of core materials for CPT transformers can improve the coupling coefficient and thereby boost the overall power transfer efficiency of the system. However, at high power and high frequency CPT applications, core losses become very high and play an important role in determining the efficiency of the system. This paper reports on a detailed investigation into the suitability of nanocrystallines as core materials for high power and high frequency CPT systems. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Sustainable Development / Problemy Ekorozwoju is the property of Faculty of Environmental Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper investigates the behavior of a high frequency parallel quasiresonant inverter fitted domestic induction heater with different switching frequencies. The power semiconductor switch Insulated Gate Bipolar Junction Transistor (IGBT) is incorporated in this high frequency inverter that can operate under ZVS and ZCS conditions during the switching operations at certain switching frequency to reduce switching losses. The proposed induction heating system responds to three different switching frequencies with providing different results. An Insulated Gate Bipolar Junction Transistor (IGBT) provides better efficiency and faster switching operations. After the complete study of the proposed induction heating system at the selected switching frequencies, the results are compared and it is decided that most reliable, efficient and effective operations from the proposed induction heater can be obtained if the switching frequency is selected slightly above the resonant frequency of the tank circuit of the resonant inverter. The proposed scheme is analyzed using Power System Simulator (PSIM) environment. [ABSTRACT FROM AUTHOR]

This paper aims toward the first step for green campus approach for Indian School of Mines ( ISM) campus. Comparative study of the performances for nine different commercialized solar panels made of Maxeon Cell Technology, HIT (Heterojunction with Intrinsic Thin layer), monocrystalline silicon (Mono C-Si), polycrystalline silicon (Poly C-Si), Micromorph, SCHOTT, amorphous silicon (a-Si), CIGS, CdTe technologies in the environmental condition of ISM are presented in this paper. This system suggests to supply the daytime electricity demand of ISM campus as well as efficient use of the huge roof areas of different buildings to setting up the photovoltaic plant. This system ensures a daily mean reduction of 8 MWh electricity consumption from grid. The outcome of this study is that a superior performance is noted for modules made of amorphous silicon technology under the typical temperature variant and dry environmental condition of ISM campus. [ABSTRACT FROM AUTHOR]

• Geographical distribution of solar energy capacity in India. • The Jawaharlal Nehru National Solar Mission is the initiative by the government of India for installing 100 GW of solar energy by 2022. • Solar Electricity for Industrial Applications in India. • Future Plan of solar power projects in India for Next Decade. Energy has a viable role-play in the socio-economicequilibrium of a country and improving overall quality of existence. Diminishing fossil fuel resources and high risks of environmental contamination associated with them has made it necessary to look for alternative and renewable resources. Due to development and necessity of new alternative renewable energy sources, bio-fuels, solar or wind energy, etc., are gaining constant popularity. Both the state and central government of India and have supported research over solar photovoltaic power during last decade. The present study discuss renewable energy and to be specific solar photovoltaic energy inclination in India along with the comparative studies of current and future developments. This paper also reviews policies and promotional steps taken by the Indian government. Finally, this review paper will assist to realize the present status, challenges and barrier for better planning and administration in setting up and utilizing alternative energy resources. [ABSTRACT FROM AUTHOR]