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PL
z oczekiwania na awarię silnika (strategia reaktywna – początek XX w.) na proaktywną. Obecnie dostępne są bardzo złożone systemy monitoringu wykrywające anomalie w silnikach. Przez porównywanie różnych przetworzonych informacji zebranych w czasie pracy silnika, pozwalają wykrywać pogarszanie się jego stanu technicznego i sygnalizowanie obsłudze konieczność interwencji w dogodnym momencie dla procesu produkcyjnego. Okazuje się, że takie zadania diagnostyczne może również realizować przekaźnik zabezpieczeniowy silnika na podstawie analizy mierzonych przez niego parametrów elektrycznych. Przykładem takiej diagnostyki jest wykrywanie uszkodzenia prętów wirnika, wykrywanie zwarć zwojowych stojana, czy też kompleksowa diagnostyka ESA, bazująca na MCSA zaimplementowana w zabezpieczeniu silnika Multilin 869 firmy General Electric (GE).
EN
Motors are an important part of the production system, any damage of motor followed by protection trip may cause serious losses for the company. In the last century, there is a change in maintenance strategy from waiting for engine failure (reactive strategy – beginning of 20th century) to proactive strategy. Very complex monitoring systems are currently available on the market. They can detect anomalies in measured motor parameters. Comparing of different processed information memorized during motor operation allows detect deterioration of its technical parameters and generate warning signal. Such role can be done by motor protection relay. An example of above advanced diagnostic in built into Multilin 869 – motor protection relay from GE are: electrical signature analysis (ESA), broken rotor bar, stator Inter-turn fault.
PL
Bogdan Kalaman urodził się 23.10.1938 r. w Pińsku na Polesiu. Rodzice byli tam nauczycielami. Ojciec Tadeusz wiosną 1945 r. był pierwszym polskim starostą i organizatorem powojennego życia w mieście Kamienna Góra. W roku 1948 z powodów politycznych został aresztowany i kilka lat spędził w więzieniu. Bogdan liceum ukończył w Zabrzu, a studia na Wydziale Elektrotechniki Akademii Górniczo – Hutniczej w Krakowie (r.1962). Był stypendystą Fabryki Maszyn Elektrycznych Celma w Cieszynie i tam w roku 1962 został zatrudniony. Szybko awansował. W latach 1971-1972 był kierownikiem zamiejscowego, cieszyńskiego Oddziału Ośrodka Komel. W roku 1972 objął stanowisko Dyrektora Technicznego (Głównego Inżyniera) Ośrodka Komel w Katowicach. Głównym jego dokonaniem na tym stanowisku było doprowadzenie do zaprojektowania i uruchomienia produkcji (w trzech krajowych fabrykach, w ciągu lat 1975-1977) specjalnej serii silników indukcyjnych mocy 1-150 HP wg amerykańskich norm NEMA, przeznaczonych wyłącznie na eksport do Stanów Zjednoczonych i Kanady. Był to nowatorski, własny pomysł Bogdana Kalamana. Rozprowadzaniem silników na rynku amerykańskim zajęła się firma Polamco w Chicago, w której B. Kalaman został kierownikiem działu silników, a następnie firma Toolmex. Eksport silników osiągnął znaczący poziom. B. Kalaman na stałe wrócił do kraju w r. 1995, by zostać prezesem zarządu i Dyrektorem Spółki Celma. Na emeryturę przeszedł w roku 2003. Zmarł w Cieszynie w czerwcu 2016 roku.
EN
Bogdan Kalaman was born on 23.10.1938 at Pinsk, east part of pre-war Poland. His parents were teachers there. After the war his father Tadeusz was district head of Kamienna Góra (town in western Poland). He was arrested by communists for political reasons and send for several years to prison. Bogdan graduated from University of Science and Technology at Krakow in 1962, getting El. Eng. M.Sc. degree. Was employed by Electric Machines Manufacturing Company “CELMA” at Cieszyn, Silesia. In 1972 got the post of Deputy Manager of Research and Development Centre of Electrical Machines KOMEL, at Katowice. His main achievement at this post was designing and leading to manufacture (by three polish factories) a special, wide range of induction squirrel cage motors for industry applications, designed acc. to American NEMA standards. The motors were distributed over US and Canadian markets for several years by Polish-American Machinery Corporation Polamco located in Chicago. When Polamco company collapsed (year 1978), Bogdan Kalaman moved to Toolmex Company, continuing distribution of polish motors. He retrieved to Poland in 1995, getting the post of Top Manager of Celma Company at Cieszyn. He retired in 2003; died at Cieszyn in June 2016.
EN
Influence of the permanent magnet assembly on the single-phase permanent magnet synchronous motor on the running motor properties was investigated. Field-circuit synchronous motor models were applied in Maxwell ver. 14. EMF, THD and cogging torque were investigated. The optimum permanent magnet assembly motor solution with the best auxiliary winding parameters was presented.
EN
High capacity induction squirrel cage motors used at different industrial driver are usually started by switching direct on line. Starting current, several times higher than nominal load current, causes thermal and mechanical, dynamic stresses dangerous for motor's structure. Both, stator and rotor windings are endangered at starting period, but stresses in rotor cages are usually considerable higher, therefore rotor design (and its manufacturing process) is of high importance for motor's durability.
EN
Induction squirrel cage motors used in many industrial drives, even of high capacity, are started by switching direct on line. Starting current, several times higher than nominal load current, causes thermal and mechanical, dynamic stresses dangerous for motor's structure. Both, stator and rotor windings are endangered at starting period, but stresses in rotor cages are usually higher, therefore proper rotor design (and its manufacturing process) is of high importance for motor's durability. Examples given in the paper show, that even standard motor with new, special, redesigned rotor can withstand as many as 70.00 long lasting starts, executed by switching the motor direct on line.
6
Content available remote A short review of energy-efficient line-start motor design
EN
The paper provides an overview of design problems and contemporary research progress in the currently very interesting field of energy-efficient line-start motors. Discussed are problems related to induction motors (1Ms), line-start synchronous reluctance motors and line-start interior permanent magnet synchronous motors (LSIPMSMs). Emphasis is given on smali rated power motors, where the LSIPMSM presents the most interesting alternative for replacing IMs widely used in low-cost single-speed drives with ventilator fans, pumps and compressors.
PL
Artykuł daje przegląd problemów projektowania i postęp we współczesnych badaniach w interesującym obszarze wydajności energetycznej silników bezpośredni włączanych. Dyskutowane są problemy związane z silnikami indukcyjnymi, silnikami synchronicznymi reluktacyjnymi z bezpośrednim włączaniem i takie same z magnesem trwałym. Nacisk zostal położony silniki małej mocy, które skutecznie zastępują silniki indukcyjne w niskokosztowych napędach w wentylatorach, pompach i kompresorach.
PL
Przedstawiono model wektorowy silnika indukcyjnego, który umożliwia badanie wpływu uszkodzenia wirnika na układ regulacji.
EN
The vector model of induetion motor is presented, that enables testing of influence rotor fault on control system.
8
Content available Loss calculation using FEM program
EN
In this study, the authors have concentrated to a cage-induction motor. They compare the loss calculations by FEM (Finite Element Method) magnetic field analyser with the loss measurements made by calorimetric chamber. The FEM program has its problems of working. The material properties and the manufacturing tolerances has to be taken into account using correction factors to the material properties of electric sheets, the current losses are solved by time stepping method and together with the magnetic field solution, but the iron losses are solved after the field analysis. The iron losses have no feedback to the field analysis. At no-load calculations, the cage-induction motor has to have a non-zero slip.
PL
W artykule autorzy porównali różne metody określania strat silnika indukcyjnego klatkowego. Porównano straty obliczone metodą FEM (Finite Element Method - Metoda Elementów Skończonych) analizy pola magnetycznego z wynikami pomiaru strat metodą kalorymetryczną. Przedstawiono rozwiązanie problemów występują-cych w programie obliczeniowym. Własności materiałów oraz tolerancje zostały uwzględnione w obliczeniach za pomocą współczynników dla materiału blach. W programie FEM straty w uzwojeniu obliczano jednocześnie z analizą pola mag-netycznego. Straty w żelazie obliczano po przeprowadzeniu analizy pola. W obliczeniach dla biegu jałowego silnika indukcyjnego klatkowego przyjęto, że poślizg nie jest równy zero.
EN
This paper presents a diagnostic conclusion block, based on a fuzzy logie approach. It proposes implementation of a decision making, algorithm based diagnostic system, in order to achieve an uninterrupted work cycle of the squirrel cage motor drives. The diagnostic conclusion interface has been designed on the basis of the diagnostic data, obtained from the analysis of the phase currents spectra and symmetrical components of the currents spectra. Indicators for the diagnostic evaluation have been selected on the basis of the solutions of the mathematical model of the motor, which takes into consideration the eccentricity of the rotor. The principle of work of the diagnostic conclusion block designed to evaluate the state of the rotor has been presented for a selected motor. Artificial intelligence, including fuzzy logie, applied in the conclusion systems increases the system's ability to derive characteristic relationships and correlations, which are not recognizable by traditional diagnostic methods, thus giving a higher possibility of forming a correct diagnosis. This is especially important in situations, when the correct interpretation of the measurement data and the diagnostic indicators requires knowledge, coming from the engineering experience.
EN
Asymmetry of induction motor, as eccentricity or fracture of bars or end-ring segments of a cage has an effect on harmonic spectrum of stator currents. In this paper I'm going to present comparison of symmetric component harmonic spectrums of induction machines stator currents with harmonic spectrums stator currents. I'm going to answer a question: can I use symmetric component harmonic spectrums of stator currents in diagnostics of induction machines. Dynamical model of this machine calculates harmonics of stator, rotor and stator-rotor inductances accounting for only global saturation of the air-gap region. The model considered various rotational speeds of the rotor.
EN
This paper presents a procedure of acquisition of diagnostic signals, needed for a comprehensive diagnostics of squirrel cage motors. The is data obtained from a Data Acquisition Card (DAQ), measuring transducers and a database. The procedure allows the measurements of the required quantities and data transfer to the server via the LAN Network or the Internet. Basic diagnostic signals required to evaluate the condition of the squirrel cage motor are three phase currents and phase voltages feeding the stator of the machine, measured at the same instant. The system delivers data needed to the comprehensive diagnostic of the squirrel cage motors, especially the ones used to detect faults which are difficult to recognize without simultaneous measurements of motor currents and control of a stator voltage symmetry. Simultaneous measurement of the three currents and the three voltages is necessary for the diagnostic methods, based on the analysis of the specific features of the motor currents component's spectrum described by the authors. This paper contains examples of the diagnostic signal analysis collected and stored with the use of the developed data acquisition system.
EN
Along with the accession of Poland to the European Union, regulations concerning apparatus for use in potentially explosive atmospheres have been changed. Basic requirements for that apparatus are regulated by the directive 94/9/EC known as the ATEX directive. The paper presents basic requirements of the ATEX directive. Moreover, experiences of F.S.E. BESEL S.A. in production of increased safety, explosion proof electric motors and a method of a protection selection are presented.
EN
This short document describes the possibility of replacing standard electrical motors with high-efficiency models in power plants. Two different drives - the coal mill and the primary air fan - are presented. In both of them the replacement of the standard motors with their energy-saving counterparts is considered. The economic assessment of this replacement is included. The paper also compares these two types of electrical motors with two different drives options, taking into account their dynamic and usage qualities.
EN
High power induction motors produce high starting currents and high voltage drops on the supply system. Especially difficult problems are when high inertia load is driven by the motors and when the short circuit power of the supply system is Iow, Then the starting time is very long and sometimes not possible. Application of the power electronic converter significantly reduces starting current which is fully controllable according references. Paper presents results of calculations of the starting processes for directly connected motor and a case of the power electronic converter.
PL
"Dwuetapowy rozruch energooszczędny silników indukcyjnych klatkowych". W artykule zaproponowano rozruch silników indukcyjnych klatkowych kształtowany dwuetapowo: początkowo poprzez regulację częstotliwości i napięcia według odpowiedniego prawa sterowania zapewniającego żądaną dynamikę a następnie poprzez regulację jedynie napięcia (od częstotliwości większej od ok. 20 Hz). Rozruch częstotliwościowy zapewnia zwiększenie strumienia skojarzonego wirnika a przez to zmniejszenie prądów fazowych i w efekcie zaoszczędzenie pobieranej przez silnik energii. Ponadto dynamika napędu w tym zakresie może być łatwo sterowana w zależności od celu i algorytmu sterowania. W drugim etapie rozruch jest ksztatłowany przy stałej częstotliwości i regulowanym napięciu. Jako urządzenie energoelektroniczne służące temu celowi zastosowano cyklokonvertor gwiazdowy pracujący w drugim etapie rozruchu jako trójfazowy sterownik mocy. Zaproponowaną metodę rozruchu uzasadniono teoretycznie oraz zilustrowano odpowiednimi przebiegami.
EN
This paper deals with problems concerning practical realization of neural detectors of rotor faults for induction motors. The design methodology for such neural detector was presented. Neural network was trained and tested using harmonics obtained from spectral analysis of the stator current and the stator current space vector modulus. The on-line operation of this neural detector in the real drive system was presented in the paper.
EN
In this time more induction motors are supplying by non-sinusoidal voltage. In diagnostics of induction motors we use harmonics of stator current (iš2s)f(0) as diagnostic signals. In this paper I'm going to answer a question: can I find any frequencies in spectrum of non-sinusoidal voltage which disturb (1š2s)f(0) signals? I'm going to present results of calculations and measurements of stator current spectrums for squirrel-cage induction motors supplied by non-sinusoidal voltage in no-load and load operations, for good motor and motor with damages (broken bars in cage, static and dynamic eccentricity). Calculations were made for a 7.5 kW squirrel-cage induction motor. Dynamical model of this machine calculates harmonics of stator, rotor and stator-rotor inductances accounting for only global saturation of the air-gap region. The model considered variations of rotational speed of the rotor.
EN
The work presented calculation and measurement results of a small power (1.5 kW) squirrel cage motor, thus verifying used for calculation two-dimensional circuit- field motor model. Using the prepared model, calculations of static (no load, load and locked rotor) characteristic as well as dynamic ( start up to no load) were compiled. Convergence of calculated and measured characteristics results varies for different motor work states. It is a result of an employment of approximations in two-dimensional circuit-field motor model as well as of varying measurement conditions. Assumed for calculations speed and temperature stability cannot be maintained in the measuring conditions. The calculating model assumption of constant parameters of stator winding frontal connections and squirrel cage ring, causes that such diverse motor work states as no load and locked rotor, could not be precisely calculated at the same time. None the less good consistence of calculated and measured results, for the full motor operating range, is obtained by assumption of mean values of inductivity and frontal connection . It may be therefore accepted, that the described model is useful in evaluation of events occurring in different states of motor operation.
EN
This paper presents technical and economical effects after applying a soft-start to the 3,7 MW, 6kV squirrel-cage motor driving paper refiner. The soft-start is voltage controller based on phase controlled SCR. Simulation and practical results after a nine-month exploitation confirmed that proposed solution achieved preliminary requirements like: current limit and decrease of pulsating torque during the first few seconds of starting the motor. These requirements allowed to increase motor lifetime and to eliminate the necessity of reconfiguration power grid before starting the motor. Additional economical effect is a possibility of saving energy due to decreasing the idle run time of the drive.
EN
The paper presents the application of PLL technique in AC drive system. In most standard speed control systems the shaft velocity is measured using tachogenerator and is given in the form of DC voltage. This voltage proportional to shaft velocity is compared with the voltage given at the input of the speed controller. Tachogenerator must meet high requirements as linear speed-voltage characteristics, ability of detection the velocity direction, negligible temperature errors and acceptable pulsations of output voltage. Its accuracy depends on magnetic flux (time-limited stability of permanent magnets - magnetic aging). Besides tachogenerator generates no signal when run at very low speed and produces commutation noises. The core of using PLL technique is the conversion of input and output velocity signals of standard speed control from voltages to proportional frequency signals. The wanted input value of velocity is given to the input of speed control system not as a voltage signal but as a frequency signal. The shaft velocity is measured using resolver that gives sine signal of frequency proportional to the actual shaft speed. This signal is next synchronized with input frequency trough the control process. Then the angular velocity of the motor shaft meets perfectly the input velocity.
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