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We consider the small-capacity meter with its technical and metrological characteristics in this paper. The diagram of the functional generator and the voltage timing diagrams are given to study operation of the functional generator. The issues of using a capacity meter during the measurement of the parameters of the railway transport devices are considered.

The article is devoted to the development of an automatic method and device for monitoring the pressing of the stator core of a powerful turbo generator during its assembling at the manufacturer. The core is assembled and pressed in an upright position in separate parts; at each stage, it is necessary to monitor places with weakened solidity. The unevenness of the compaction density causes a relative displacement of the active steel sheets and losses of iron, as well as the appearance and development of certain defects (loosening of the teeth of the extreme packages, coloring of fragments of the active steel sheets, local closure of the sheets and heating of the packages), which can eventually cause severe accidents and failure of the turbo generator. Existing methods, including automatic ones, do not allow performing reliable monitoring. The method proposed by the authors for detecting places with weakened solidity is based on automatic measurement of the specific pressure of pressing during deformation of special control samples. A device for its implementation has been developed, which is a ring installed on the end surface of the core. Cells with control samples are evenly placed in the ring. The largest decrease in the sample thickness caused by the highest specific pressure corresponds to the smallest defect, and vice versa. As a pressure converter, it is proposed to use a flat metal membrane and a capacitive sensor with a digital output. The characteristics of the converter were calculated and experimentally verified. The specific pressure measurement results were processed using a special electronic unit. The device that has been developed makes it possible to improve labor productivity when monitoring the core, diagnose defects with greater reliability and eliminate them, and, ultimately, increase the reliability of the turbo generator as well as its durability.

Background. Control of moisture and impurities of agricultural products is the main production task affecting their quality, reduction of energy consumption during storage and processing, cost, technical and nutritional values, availability of useful consumer properties. Materials and methods. A two-stage method for determining moisture and impurities in products is proposed, the study of which is carried out by computer modeling in the SimInTech environment with obtaining the results of model calculations in real time based on programmable blocks. Results. A simulation model of the proposed method is constructed and the results of its calculation are obtained in comparison with the known method for determining the parameters of measuring circuits. A functional scheme of the proposed information and measurement system for monitoring humidity and impurities of agricultural products has been developed. Conclusion. The results of the calculation showed that the proposed method has a significant advantage in terms of the relative error of the results of determining informative parameters.

One of the most important parameters of powerful hydro generators (HG) is the air gap between the rotor and the stator, and its deviation from the set norms is a defect that can lead to serious accidents. Therefore, the size and shape of the gap must be monitored both during inspections and during operation of the machine. The aim of this paper was to develop a secondary measuring transducer providing accuracy and resolution for a capacitive gap sensor formed by coplanar parallel electrodes.It is shown that the reliability and safety of operation of powerful HG inextricably depend on the timely detection of their defects, especially during operation. One of the most important parameters of the HG is the air gap between the rotor and the stator, and its deviation from the set norms is a defect that can lead to serious accidents. Therefore, the size and shape of the gap must be monitored both: during inspections and during operation of the machine. The paper discusses the features of measuring the air gap in a powerful HG, as well as existing modern methods and means of measurement.It is shown that for measuring the gap in capsule HG, one of the most suitable means is a meter, which includes a capacitive sensor mounted on a central bore of the stator core. Commercially available gap meters with capacitive sensors are not suitable for use on HGs. Commercially available meters with capacitive sensors, by their certain characteristics, are not always suitable for use on HGs.A secondary measuring transducer with improved characteristics is proposed for a capacitive gap sensor formed by coplanar parallel electrodes.The converter is developed on the basis of a balanced compensation bridge measuring circuit. The control action in the device is formed by the phase of the unbalancing signal.The structural diagram of the converter is presented and the algorithm of its operation is described. The process of forming a measuring output signal proportional to the sensor working capacitance in the circuit is considered.The use of a capacitive sensor with coplanar parallel electrodes and the proposed secondary measuring transducer will ensure high accuracy and resolution when measuring the air gap.

Background. The possibility of constructing non-standard multi-element measurement circuits of capacitive sensors in the SimInTech dynamic modeling environment is investigated. Materials and methods. On the basis of the built-in libraries of the software environment, computer modeling of measuring circuits of sensors is performed using two methods of constructing the model – я and experimental. Results. Models of an operational amplifier and a measuring circuit of a four-element RC circuit are constructed, their operability is checked and a comparative analysis is carried out with existing mathematical models. Based on the SimInTech programming language, a separate calculation block is programmed, which allows performing complex computational operations directly in the model. Experimental and calculated curves describing the dependence of the change in the output voltage on the nominal parameters of the measuring circuit are obtained. Conclusion. The working model of the operational amplifier is developed and the expediency of using the environment for the study of multi-element measuring circuits of capacitive sensors based on the built-in mathematical solver is confirmed.

The troubleproof and efficient work of powerful turbogenerators depends on the stability of their main mechanical parameters, which include the stator core pressing. The aim of the work was to describe the possibility of using a multielement capacitive sensor with coplanar electrodes to measure the movement of disk springs of the stabilizer systems power batteries in the turbogenerator stator core.The state of the core pressurizer can be indirectly assessed by measuring the displacement of the disk springs in power accumulators, which are installed on the tightening prism of the core instead of the compression nuts. To measure the movement of springs, a coplanar capacitive sensor with sectoral electrodes built into the power accumulators design is proposed. Each sector contains its own elementary sensor formed by coplanar electrodes. Each elementary sensor in each sector is placed on an annular dielectric plate and is formed by coplanar electrodes that are part of coaxial concentric rings. The sensor consists of a high-potential, low-potential and grounded electrodes. A grounded electrode is located between the high-potential and low-potential electrodes, as well as around them.A simplified analytical calculation model for obtaining the analytical response characteristic of the change in the informative component of the sensor electric capacity on the course of the disk springs in the CA is presented. The reliability of the model and the response characteristics are confirmed experimentally by testing a laboratory prototype of a capacitive sensor.

In this paper, we report of the solving the actual problem of control the air gap in the hydrogenerators. The aim of the study was development of a computerized information-measuring system for measuring the air gap in the hydrogenator, which used two capacitive sensors with parallel coplanar electrodes, and the method of determining the shape of the envelope parameters hydrogenerator rotor poles relative to the center axis of rotation, using the measurement results of the air gap.In practical studies of the sensor circuit it has been shown that its use allows for the informative value of the sensor capacitance conversion function to obtain a high accuracy and resolution measurement with digital linearization of converting function of the sensor with use program utility. To determine the form deviations of the envelope line of the rotor pole from the ideal cylinder, which is one of the main structural defects of the technological errors as results the distortion of the shape of the air gap in the hydrogenator, when the machine was manufacture and assembly. It is proposed to describe the shape of the envelope to use a Fourier transform. Calculation of the coefficients of the Fourier series is performed using the method of least squares as the regression coefficients.Application of this method in processing the measuring data in a computerized information-measuring system the developed with the primary converter with coplanar parallel electrodes allowed attaining the high measurement accuracy and resolution informative in magnitude of the capacity.

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The problem of developing a sensor for measuring of moment forces of inertia and gravitation with minimal noise and minimal rigidity of the torsion suspension of proof mass (PM) is formulated. The possibility to solve this problem by a differential capacitive system, which simultaneously provides forming of the useful signal and reducing the torsion rigidity is shown. Sensor’s electromechanical circuit with differential electrostatic system is described. Method of calculating the electrostatic capacitance of the capacitor with an inclined plate is proposed. Calculations of electrical and mechanical forces moment acting on the movable plate of the differential capacitor in quasi-static mode are performed. It is shown that the main factor leading to the pull-in effect in the differential capacitor is the asymmetry of electrostatic system. The coefficient of asymmetry of the differential electrostatic system is introduced. The dependence on voltage of the resonance frequency of the sensor is received. The areas of the quasi-static stability of the system are calculated. It is shown that their boundaries are determined by the value of the coefficient of asymmetry, as well as by the value of the resonant frequency of the PM. It is shown that for reducing the resonant frequency of the sensor in more then ten times an unrealistically low values of the coefficient of asymmetry are required.

The capacitive method of control of degree of loosening of hatch-end packages of tooth zone of stator core of power turbo generator is proposed. It is shown that loosening is related to initiation of gas intervals between the sheets of package Control is carried out at overlapping of capacitive sensor on loosening package over the layer of dielectric. Sensor is the system of alternating highly-potential and low-potential parallel coplanar electrodes. A calculation model is developed and all components of electric capacitance of sensor are determined. These components is presented as dependences, relating sizes of sensors, thickness of isolating dielectric layer between surface of sensor and surface of package, and size of gaps between the sheets of package. It is shown that information about appearance of loosening is a change of one of components of electric capacity of sensor. Analytic dependences which have been obtained in this paper can be used for designing of real industrial device. [ABSTRACT FROM AUTHOR]