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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 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]

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]

This paper describes the design of a simple non-contact-type pressure transducer using a Bourdon tube and a Hall sensor where the effect of atmospheric temperature is compensated. In this design, a pressure sensing Hall IC is fixed with the nonmagnetic aluminum casing of a Bourdon gauge in front of a tiny disc-type permanent magnet rigidly attached with the free tip of the Bourdon tube. With the increase of pressure of the fluid inside the Bourdon tube, the free end along with the magnet moves toward the Hall sensor, and the magnetic field intensity due to the magnet on the Hall sensor increases with an increase of pressure. Due to this magnetic field, the outputs of the Hall sensor and the transducer circuit consisting of a differential amplifier and an instrumentation amplifier increase with the increase of pressure of the fluid inside the Bourdon tube. The transducer circuit consists of a unity gain differential amplifier circuit where the output of a second identical temperature sensing Hall IC is subtracted from the pressure sensing Hall IC output in order to compensate the effect of ambient temperature in the proposed transducer. The theoretical equations describing the operation of the transducer are derived in this paper. The static characteristic curves of a prototype design of the transducer are determined experimentally. The experimental results are reported in this paper. The characteristics curves are found to follow the theoretical equations with good repeatability and are free from ambient temperature effect. [ABSTRACT FROM AUTHOR]

The conventional LVDT is generally used as displacement transducer but has some limitations such as small linear range, measurement errors due to stray capacitance effect, electromagnetic interference effect, and core loss effect. In this paper, a modified LVDT type displacement transducer has been proposed in order to overcome these limitations of conventional LVDT. The proposed LVDT will consist of only two identical coils instead of three coils of conventional LVDT. This design does not require any excitation coil. In this design, two identical coils wound on a former made of ferromagnetic material act as displacement sensing inductive coils with specially designed movable core. The design has been analyzed under three cases. It has been shown that the range of the displacement transducer is about 50% of the overall length of the sensor under two cases like conventional LVDT and is about 100% of the overall length of the sensor under the third case. So in this paper, a displacement transducer has been designed and tested experimentally considering only the third case with unlimited range equal to the entire length of the sensor. The transducer consists of an op-amp-based differential inductance measuring circuit and an output instrumentation amplifier. The performance equations of this sensor under three cases and of the transducer under third case are derived in the paper. The experimental results reported in the paper are found to follow the derived equations with very good linearity and repeatability. [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]