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In this article, basic cell (BC) of a novel swi-tched capacitor converter (SCC) has been proposed first. After that, the generalized structure of proposed SCC is developed. The developed SCC requires reduced number of switches, drivers, diodes, capacitors, and lower number of conducting switches in current flow paths and capacitor charging paths as compared to the other recently developed SCCs. A switched capacitor multilevel inverter (SCMLI) utilizing two numbers of generalized SCCs is developed next. Further, cascaded extension of proposed SCMLI is realized and analyzed for symmetric and asymmetric dc source configurations. A detail analysis of optimum selection of capacitance for switched capacitors of 13-level SCMLI is presented. An extensive comparison study shows that the proposed SCMLI requires lower number of components as compared to other SCMLIs. Further, the proposed structure has minimum cost function per level per boosting factor as compared to the other SCMLIs. Extensive experimental results considering fundamental switching frequency scheme are presented to validate the merits and effectiveness of the proposed structure. [ABSTRACT FROM AUTHOR]

The principle of centrifugal force produced by flowing fluid through the semicircular section of a pipe line is not sufficient to explain the characteristic of the centrifugal force type flow transducer developed from this principle. In this study, a modified form of this flow transducer is developed using a modified force sensing technique. This modified force principle explains the characteristic of the flow transducer to a very good extent. The modified force produced in the modified transducer system is composed of four components namely, centrifugal force, momentum force, damping force and restoring force. These forces produce the identical downward and upward movements of the lever ends of a common balance which is initially made horizontal at zero flow by using similar sensing U‐tube and dummy U‐tube. These movements are sensed by two identical inductive sensors. The static characteristic equation of the prototype unit of the transducer using the modified force sensing technique is derived mathematically in the study. The equation coefficients are calculated from the design parameters and are found to be matched with the same obtained from the average characteristic of repeated experiments performed under the same laboratory environment. Thus the proposed modified model appears to be established. [ABSTRACT FROM AUTHOR]

In this paper, a novel 15 level symmetric switched capacitor multilevel inverter (SCMLI) structure is proposed first. The structure is developed by using 3 non-isolated DC power sources. The capacitors utilized in the structure can be charged to the summation of all the power supplies by turning ON the minimum number of switching devices. After that a generalized structure of the proposed SCMLI is developed. The voltage and current stresses for different switches of the proposed general structure are discussed. The selection procedure of switched capacitors for the proposed 15 level inverter is presented for resistive and resistive-inductive load conditions. A detailed comparison study of the proposed structure with other recently developed structures shows that the proposed structure requires reduced number of components and the number of switches in the conducting path as compared to other SCMLI structures for generating an output voltage level. Further, the overall cost of the proposed and suggested topologies has been compared based on a cost function (CF). It has been observed that the proposed structure is more cost effective as compared to others. An extensive experimental study conducted on a 15 level SCMLI laboratory prototype proves the effectiveness and merits of the proposed structure. [ABSTRACT FROM AUTHOR]

In this paper, a novel structure of switched capacitor converter (SCC) is proposed. First, the basic unit of the proposed SCC is presented. After that, a generalized structure of the proposed SCC is discussed. The presented SCC uses one dc source, several switches, diodes, and capacitors to produce multistep dc boosted output voltage. The capacitors in the SCC can be charged in trinary asymmetrical pattern. A detailed comparative study between the proposed and other recently developed SCC structures is presented. It is shown that the proposed SCC can produce an output voltage level with lower total standing voltage and lower maximum switch stress voltage as compared to most of the suggested SCC structures. Further, a switched capacitor multilevel inverter (SCMLI) based on cross-switched multilevel inverter has been developed and analyzed for symmetric and asymmetric dc source configurations. For fair comparison with the existing SCMLI structures, the overall cost of the structures is compared based on a cost function (CF). The proposed SCMLI provides lower cost function/output voltage level (CF/NL) in comparison with most of the other SCMLI structures for both symmetric and asymmetric dc source configurations. Extensive experimental studies validate the operation and performance of the proposed SCMLI structure. [ABSTRACT FROM AUTHOR]

Aiming ultra-reliable and mountable connectivity of tremendously high data rates in the Tb/s era with zero-perceived latency of 6G systems, next generation smart grids will need to captivate the advantages of breakthrough novel technology perceptions, incorporating THz wireless links, broadband and machine learning-based models designs, protocols and management practices. Motivated by the transformation potential of 6G systems, this paper deals with an island detection approach in 6G paradigm for an active distribution network. The proposed island detection method is tailored to adopt the breakthrough technologies of 6G, particularly, ultra-low latency, high volume data transmission and machine learned intelligent system. This methodology calculates the angular sum of the positive and the zero-sequence phase angle of the voltage at point of common coupling combined with random forest (RF) machine learning to identify islanding conditions. The technique has a robust resistance to noise due to the inherent nature of RF, has no consequences on power quality and exhibits a zero non-detection zone. It has the ability to differentiate between islanding and non-islanding events precisely even during active and reactive power discrepancy and transients similar to islanding. The method depicts a high testing accuracy of 98.46% with an island detection time of 52 ms. [ABSTRACT FROM AUTHOR]

In the smart-grid paradigm, since distribution systems are controlled by various independent operators, it becomes inevitable for all dispatchers to have a wide-area view of the network for situational awareness and protection. This visualisation is accomplished with the aid of protection (p) type micro-phasor measurement unit (μPMU) installed at the bus of the respective distributed generation (DG). One of the pressing issues with DG's is the concern of inadvertent islanding that disrupts orderly reconnection besides posing hazards to utility workers. In view of this, this study proposes a real-time inadvertent islanding detection by μPMU. The voltage and current phasors obtained from these μPMUs by discrete Fourier transform are further processed by Fortescue transform to compute the angle of sequence components. The absolute angle difference between positive and zero components is used to initiate signal for accomplishing intelligent islanding under islanded condition. The simulation results prove the method to be robust, computationally efficient, non-detection zone free and feasible. Most significantly, as measuring equipment and relay are already present in p type μPMU, therefore unlike other detection methods, no extra arrangements are required in this method making it economically viable and easy to implement. [ABSTRACT FROM AUTHOR]

This paper is devoted towards life cycle economic analysis (LCEA) of a solar photovoltaic (PV) powered tri-cycle. The paper is meant to propose a more systematic approach in determining the optimum use of scarce resources in order to determine the most cost-effective option of the solar tri-cycle. This analysis is based on the life cycle cost of this solar vehicle, involving its comparison with the customary fuel-based tri-cycle which exhibits the relatively less expenditure of the solar alternative. The economic analysis takes into account the fact that over 20 years, the overall price of solar component, replacement and electricity charges, is much lower as compared to that of a fuel-based tri-cycle in India taking into consideration the fuel cost, maintenance and annual inflation over the same period. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A dual output direct AC–AC series resonant converter is presented in this paper, to meet the requirements of modern domestic induction heating. To address the significant limitations of the classic induction heating system, a hybrid control approach comprising pulse frequency modulation and asymmetrical duty-cycle control is developed. A single source is connected to multiple loads with this control technique to achieve minimum switching losses; power controllability of two loads is achieved independently and simultaneously. The power controllability of two loads is achieved independently and simultaneously. This research presents an induction heating system that can heat both ferromagnetic and non-ferromagnetic materials, such as steel and aluminum. A prototype is developed to use switching frequencies of 30 kHz and 150 kHz for steel load and aluminum load, respectively. The experimental setup resulted in an efficiency of 97.5% under wide load resonant condition. The suggested hybrid control approach allows the converter to regulate a wide range of output power while increasing efficiency, making it suitable for practical induction heating. [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]

This paper presents a fuzzy Markov model to efficiently incorporate the influences of maintenance scheduling as well as aging of generating units on failure-repair cycle for computation of state probabilities. The proposed model, different from conventional models that are based on a probabilistic approach, employs a fuzzy set concept together with a probabilistic Markov model. This model incorporates fuzzy mean time to failure (FMTTF) and fuzzy mean time to repair (FMTTR) instead of crisp (expected) values for capturing the generating unit uncertainties more effectively through expert evaluation. The fuzzy state probabilities are computed from FMTTF and FMTTR values using fuzzy arithmetic operations for evaluation of the reliability index, fuzzy loss of load probability (FLOLP). Case studies for the maintenance scheduling of a captive power plant catering to an aluminum smelter have been formulated to demonstrate that fuzzy state probabilities as well as FLOLP provide a better explanation than the respective crisp counterparts. [ABSTRACT FROM AUTHOR]

The present paper describes a converter where both series and parallel resonant circuits are used. In order to minimize losses, switching is made at zero current crossover (ZCS). The converter described in this paper has four MOS-controlled thyristor (MCTs) in H-bridge configuration (Full bridge). It is used for an induction cooking-range with two hot zones. The switching frequency is 50 kHz. To optimize the system efficiency, different control strategies are discussed. [ABSTRACT FROM AUTHOR]

The flow head of an orifice-type capacitive flow sensor for a conducting liquid consists of a vertically mounted metallic orifice plate in a horizontal pipeline made of insulating material and a rigidly grounded metallic ring or sensing ring placed surrounding the pipeline at a small distance from the orifice plate where the capacitance between the orifice plate and the sensing ring follows a linear relationship with flow rate as reported in the literature. In this paper, a further study on the effect of position of the sensing ring on the sensor capacitance has been carried out along with the modification of the simple parallel plate capacitance principle described in the earlier work by the real disk-type capacitance principle. From this paper, it has been observed that for any position of the sensing ring near the orifice plate, the sensor capacitance decreases linearly with the increase of flow rate and follows the modified capacitance principle similarly as that observed in earlier work. It has also been observed that the sensing ring distance-sensor capacitance product increases almost linearly with the increase of sensing ring distance. From the experimental study of the proposed orifice type capacitive flow sensors installed on two different pipelines, the said modified theory of the sensor appears to be verified in the present paper where the experimental results are reported. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]