Některé progresivní směry vývoje psychologické přístrojové techniky (Nástin teoretických základů psychologických přístrojových metodik)

Katedra psychologieFilozofická fakult

Comparing the Low-Cost Measuring Devices for Standstill Frequency Response (SSFR) Testing for Electric Machines

This paper compares the different versions of hardware realization of low-cost device for standstill frequency response SSFR testing. The SSFR testing is a modern method used for testing and parameter identification for electrical machines especially for synchronous machines (high power generators for power stations). This paper shows the methods how to realize this SSFR testing device for machine identification by general purpose components (to achieve universal device not only for SSFR testing but also for purposes of more universal usage (i.e. measuring of non-linear power systems, power system fault identification, non-symmetrical differences measurement, etc.). This modern method makes it possible to replace the Sudden Short-circuit Measurement Method and thus saves the mechanical construction and lifetime of the machine, which might be otherwise reduced due to the strong dynamic forces that occur in this type of measurement. Proposed devices were realized in university laboratories for purpose of getting acquainted with the practical properties of this method and also for didactic purposes (both in terms of the SSFR method itself and in term of realization of a real equipment with given properties)

Optimal SRM-control algorithm to achieve maximum torque and real converter limits

The paper deals with an “optimal” control algorithm for switched reluctance motor (SRM). The principle of this control method is based on a maximal torque per ampere (MTPA) criterion which prefers the maximal average value of torque, regardless of the torque ripple, in compare to the commonly used method, where the constant torque regulation is preferred. The proposed control method uses precalculated optimal rotor start and stop current pulses’ positions. These optimal values are obtained by numerical simulations under the data set obtained by a real measurement on electromechanical system SRM machine and its power converter. Mathematical model of this SRM and measurement method are both described in the paper. The algorithms used in simulation of SRM consider also the non linear iron core of SRM, maximal voltage limitation (maximal supply voltage), high speed operation region and current limitations

The leachability of the mercury from the contaminated materials

Půdy a říční sedimenty s vysokými obsahy rtuti byly vyluhovány řadou extrakčních činidel (vodou, kyselinou sírovou, dusičnanem draselným, kyselinou dusičnou, kyselinou chlorovodíkovou, chloridem vápenatým a chelatonem). Obsahy rtuti v extraktech těmito činidly byly převážně menší než 0,001 mg.l-1. Vzorky půd a říčních sedimentů byly postupně obohaceny přídavkem 10, 20, 50 a 100 μg.g-1 rtuti (přídavkem dusičnanu rtuťnatého o koncentraci c = 1,00 g.l-1). Také koncentrace rtuti ve výluzích z obohacených vzorků vykazovaly převážně nízké hodnoty. Vzorek půdy PA a vzorek říčního sedimentu SB byl rozdělen do 5 frakcí, podle velikosti zrna ( > 10; 2 – 10; 0,63 – 2; 0,2 – 0,63; 10; 2 – 10; 0.63 – 2; 0.2 – 0.63; < 0.2 mm). Three of the finest fractions of soil PA (P3 – P5) and sediment SB (S3 – S5), were enriched by 20 μg.g-1 of mercury and extracted by the above mentioned reagents. The concentrations of the mercury were acquired by the statical and dynamical extraction method. The results of the statical method were higher than the ones acquired by the dynamical extraction method. The fractions of the soil and of the sediment (0.63 – 2 mm), enriched by the addition of 50 μg.g-1 mercury were extracted in the time of 4.5 months by nitrate acid and by EDTA. The equilibrium was reached after about 150 000 minutes in both cases by nitrate acid. In the extracts of EDTA was the equilibrium reached after about 120 minutes. Furthermore, the dependence of the leachability of the mercury on the particle size was observed. The finest fractions of the soils PA (P3 – P5) and the ones of the sediment SB (S3 – S5) were enriched by addition of 50 μg.g-1 mercury. The particle size does not affect the extracted concentration of mercury, as it was expected

Converters for switched reluctance motor - topology comparison

The paper deals with the comparison of SRMconverter topologies, focusing on comparing the number and the dimensioning of semiconductor elements for the medium power engine (from approx. a hundred watts to tens of kW). The paper considers basic well-known configurations (e.g. an asymmetrical half bridge, etc.) and special types of topologies (e.g. current source topologies, quasi-current source inverter etc.). Special attention is paid to topologies enabling the use of standard semiconductor modules (mass-produced for drives with induction motors)

Multichannel coincidence circiut with settable threshold level for ToF AFP detector

The detectors and signal processing chains in the experimental particle physics produce the data in the order of tens GB per hour due to high rate events. The trigger module, as one of the units for signal processing in the Time-of-Flight detector, uses the MCC (Multichannel Coincidence Circuit) for data stream reduction based on the settable threshold level used for the selection of the events related to the ongoing physical experiment. In this paper the MCC design of the circuitry and firmware is described. The performance of the MCC has been verified by measurement and the results proved the proper function of the device. The next generation of the trigger module will be based on this MCC and installed on the LHC particle detector in CERN

Intelligent high current sensor for various frequency

The paper proposes a design procedure of a current sensor. The winding design is analyzed regarding its impact on the operational characteristics and is evaluated for a preferred application. The paper also discusses the measurement results and given frequency characteristic and quality factors of the laboratory prototypes. The sensor is designed for a current up to 200 A and frequency up to 120 kHz. The sensor is equipped with an electronic unit in a common housing. The electronic transducer evaluated the measured data and produces the digital output signals which is easy to transfer even to a long distance