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PL
Układy napędowe maszyn wyciągowych na szybach wydobywczych w kopalniach węgla kamiennego i rud miedzi bazują na silnikach prądu stałego wzbudzanych elektromagnetycznie. Sprawność energetyczna tych silników wynosi około 90%. W artykule przedstawiono silniki alternatywne: silnik prądu stałego wzbudzany magnesami trwałymi; silnik wzbudzany magnesami trwałymi i komutacją elektroniczną. Sprawność wymienionych silników jest większa, a ilość traconej energii w silnikach jest mniejsza.
EN
The drive systems of winding machines, on production shafts of coal mines and copper ores mines, are based on electromagnetically excited DC motors. The energy efficiency of these motors is around 90%. The alternative motors are presented in the article: DC motor excited by permanent magnets; a motor excited by permanent magnets and electronic commutation. The efficiency of these motors are greater, and the amount of energy lose in motors are smaller.
PL
Układy napędowe maszyn wyciągowych, na szybach wydobywczych w kopalniach węgla kamiennego i rud miedzi, bazują na silnikach prądu stałego wzbudzanych elektromagnetycznie. Sprawność energetyczna tych silników wynosi około 90%. W artykule przedstawiono silniki alternatywne: - silnik prądu stałego wzbudzany magnesami trwałymi, - silnik wzbudzany magnesami trwałymi i komutacją elektroniczną. Sprawność wymienionych silników jest większa, a ilość traconej energii w silnikach jest mniejsza.
EN
The drive systems of winding machines, on production shafts of coal mines and copper ores mines, are based on electromagnetically excited DC motors. The energy efficiency of these motors is around 90%. The alternative motors are presented in the article: - DC motor excited by permanent magnets, - a motor excited by permanent magnets and electronic commutation. The efficiency of these motors are greater, and the amount of energy lose in motors are smaller.
EN
In the paper a procedure for determining the observer parameters for selected types of electrical motors is discussed. The procedure is based on the identity observer developed by Luenberger. The paper presents determining the parameters using calculation examples for the DC motor and also for the permanent magnet synchronous motor (PMSM), which utilize the extended state vector to estimate the back electromotive force (BEMF). Presented observer for PMSM does not need to use the information about load torque. The main task of this study is to show how to utilize these general theory to a specified type of motors. Such procedure avoids the use of time-consuming methods of the parameters selection, which are based on random algorithms or the computational intelligence.
PL
Artykuł przedstawia strukturę i właściwości zespołu wielosilnikowych napędów grupowych DC transportującego formowane pasmo metalu. Każda z grup napędowych jest sterowana przekształtnikiem tyrystorowym od strony obwodu tworników. Obwody wzbudzenia silników grupy są zasilane z jednego prostownika półsterowanego z dodatkowymi rezystorami do indywidualnego ustawiania prądów wzbudzenia. Rezultatem uwarunkowań technologicznych związanych z dociskiem hydraulicznym, niedoskonałością geometryczną rolek napędowych, warunkami termicznymi i plastycznością pasma jest występowanie asymetrii prędkości liniowych, które determinują określone wady półproduktu. Wykorzystując enkodery do pomiaru prędkości obrotowej silników i rolek transportowych oraz programy DasyLab i MATLAB obliczono wartości prędkości liniowych, na podstawie których określono stopień asymetrii prędkości liniowych rolek. W końcowej części artykułu przedstawiono podsumowanie i wnioski.
EN
The paper presents the structure and properties of the unit comprising several groups of multi-motors DC drives. The unit drives the transport line of molded steel band. Each drive group is controlled by the SCR rectifier in armature circuits. Excitation circuits of the group of motors are powered from a single semicontrolled rectifier with additional resistors to set the individual excitation currents. The result of technological conditions associated with hydraulic clamp, geometrical deviations of drive rollers, thermal conditions and elasticity of the band is the occurrence of asymmetric linear velocity that determine specific defects of the slabs. Linear speeds of transport rollers were calculated using encoders to measure the speed of motors and programs DasyLab and MATLAB. Asymmetry of the linear speeds of rollers was determined. The summary and conclusions are presented at the end of the paper.
5
Content available remote Historia napędów elektrycznych w trakcji
PL
Rok 1879 uważany jest za początek rozwoju trakcji elektrycznej. W tym właśnie roku Werner von Siemens zbudował i przedstawił na wystawie rzemiosł w Berlinie, pierwszy elektryczny pociąg pasażerski napędzany silnikiem prądu stałego zasilany z sieci trakcyjnej 600 V DC. Od tego czasu trakcja elektryczna ciągle się rozwija. Kolejne etapy rozwoju układów napędowych lokomotyw i systemów zasilania, to: - napęd lokomotyw trójfazowymi silnikami indukcyjnymi pierścieniowymi, zasilanymi bezpośrednio z sieci trójfazowej 3,3 kV, 16 2/3 Hz), - napęd lokomotyw jednofazowymi silnikami prądu przemiennego, zasilanymi poprzez jednofazowy transformator zabudowany w lokomotywie, sieć trakcyjna 1- fazowa 15 kV, 16 2/3 Hz, - napęd lokomotyw silnikami szeregowymi prądu stałego, sieć trakcyjna 3 kV DC, - napęd lokomotyw silnikami indukcyjnymi klatkowymi, sieć trakcyjna w zależności od kraju: 3 kV DC, 15 kV AC, 20 kV AC, 25 kV AC. Najnowsze osiągnięcia trakcji elektrycznej to kolej magnetyczna.
EN
The beginning of electric traction dates back to 1879. It was during Berlin. Trades Exposition in 1879 that Werner von Siemens built and showed first passenger electric railway driven with direct current motor supplied from 600 V dc traction network. Since then electric traction has been undergoing continuous development. The successive stages of locomotive drive systems and supply systems evolution may be enumerated as follows: locomotive three-phase induction slip-ring motor drive, supplied directly from 3.3kV, 16 2/3 Hz three-phase network, locomotive one-phase ac motor drive, supplied via one-phase transformer located in the locomotive, one-phase, 15 kV, 16 2/3 Hz traction network, locomotive dc series motors drive, 3 kV dc network, locomotive induction cage motor drive, traction network varies from country to country (3 kV dc, 15 kV ac, 20 kV ac, 25 kV ac). The magnetic railway is the most current achievement in electric traction.
PL
W pracy przedstawiono numeryczny model maszyny prądu stałego z uzwojeniami kompensacyjnymi i komutacyjnymi. W rozpatrywanej maszynie uzwojenia kompensacyjne i komutacyjne połączone zostały w gałęzie równoległe. Przeanalizowano wpływ niesymetrii rozpływu prądów w równoległych gałęziach uzwojeń kompensacyjnych na komutację. Do wyznaczenia rozkładu pola magnetycznego zastosowano metodę elementów skończonych. Przedstawiono wybrane wyniki obliczeń numerycznych.
EN
A numerical model of a DC machine with compensation and commutation windings connected into parallel circuit limbs was presented in this paper. The influence of the current distribution asymmetry in above mentioned limbs on the commutation process was analysed. Selected results of numerical calculations were presented.
PL
Silniki prądu stałego dużej mocy pracują w układach napędowych maszyn wyciągowych w górnictwie i w układach napędowych walcarek w hutnictwie. Są to silniki wielobiegunowe o stosunkowo małej znamionowej prędkości obrotowej. Duża różnica w średnicach wirnika i komutatora powoduje, że chorągiewki łączące końcówki uzwojenia z działkami komutatora mogą mieć długość nawet około jednego metra. Chorągiewki te, w czasie pracy silnika są poddane działaniu sił elektrodynamicznych i sił bezwładności. Doświadczenie eksploatacyjne wykazuje, że chorągiewki są najbardziej awaryjnym węzłem silnika i często łamią się. Na przykładzie silnika walcowniczego, o średnicy wirnika D = 4500 mm, średnicy komutatora Dk = 2280 mm i liczby działek komutatora K = 1050, zilustrowano siły działające na chorągiewki oraz wpływ mocowania chorągiewek na ich trwałość.
EN
DC motors operate as high power drive systems in mining hoists and drive systems in the steel mills. These are multipolar motors with relatively low rated speed. The large difference in diameters of the rotor and of the commutator results in risers' length of up to one meter (riser is commutator part connecting winding end to the commutator bar). The risers, when the engine is working, are subjected to electromagnetic forces and inertia forces. Operational experience shows that the risers are the most-likelyto- fault engine points and often experience failures. Forces acting on the risers are illustrated together with the effect of type of attachment of the risers on their durability. Example used is rolling-mill motor with a rotor diameter D = 4500 mm, commutator diameter Dk = 2280 mm and the number of commutator bars K = 1050.
8
Content available remote Optimal slot opening in permanent magnet machines for minimum cogging torque
EN
Based on the 2-d model of a slot and the effective flux density distribution in an equivalent slotless machine, this paper presents an analytical technique for accurately determining the optimal slot opening for minimum cogging torque in permanent magnet machines. It is then used to derive the relationship between slot opening and cogging torque for machines having different combinations of slot number and pole number. In addition, it is applied to slot pairing to effectively reduce the cogging torque. Analytical results are verified by finite element analyses and experiments.
PL
Wykorzystując dwuwymiarowy model szczeliny i rozkladu indukcji w artykule zaprezentowano technikę określania optymalnej szczeliny dla uzyskania minimalnego momentu zakleszczania się. Analizę wykorzystano do określania momentu w maszynach o różnej liczbie szczelin i biegunów. Wyniki analizy zweryfikowano eksperymentalnie i obliczeniowo (metodą elementu skończonego).
EN
The basic structure of electric drive control system contains current control circuit (inner loop) and speed control circuit (outer loop). Two criteria are used in setting current and speed controllers: symmetry and absolute value. In application, the goal is to limit the quantity of extra parts used with PM BLDC motors, which are usually small power motors. The simplification of the drive structure may be achieved, for instance, by eliminating tachogenerator and using rotor position sensor for calculating motor rotational speed. The rotor position signals are then converted into signals corresponding to motor's actual speed. The time interval between two rotor characteristic positions is inversely proportional to motor's rotational speed. The measurement delay changes with motor speed and the typical controller settings criteria cannot be applied, since they are based on assuming that time delay is constant. The paper presents a novel method of selecting speed controller with parameters changing with rotational speed. The controller design is shown. Proposed control system structure and method of selecting controller's settings ensure that the drive attains properties similar to those of a drive using speed controller system with symmetry criterion used. The theoretical considerations have been verified with help of computer model and laboratory tests.
10
Content available Układ napędowy klimatyzatora
EN
In this paper structure and main characteristics of DC brushless motor driver of the air-condition machine have been presented. The DC brushless motor with permanent magnets supplied by three-phase voltage converter has been used. This paper contains description of developed and manufactured motor and its converter as well as chosen examination results of the driver. Developed motor is characterized by very cogging torque and the converter contains very few elements and is of small dimensions.
11
Content available Silniki BLDC - klasyczne metody sterowania
EN
The definition of BLDC motor classical control method, terminology and classification of the classical control strategies are described in the paper. The proposed classification based on electronic commutator transistors switching sequences. Equivalent circuit diagrams in steady state for each strategy are shown. Based on those diagrams derived a formulas to calculate current increasing and falling times for unipolar and bipolar strategies. Those times show the differences in transistors switching frequencies. The advantages and disadvantages of all presented control strategies are indicated too.
EN
In the paper the control system for permanent magnet brushless DC motor is considered. The simulation research results as well as the results of the experiment result carried out using the control system are presented. There were the following conditions of the experiment: speed measurement was performed with the position sensor, the frequency of position sensor signals were proportional to motor velocity. Due to the measurement delay time variability and dependence on the rotational speed of the motor, adaptation regulator was used as a part of the control system. The algorithm of the adaptation regulator stetting parameters selection is referred in [3]. As a results of simulation and experiment test, the authors shown waveforms of speed and torque of PM BLDC motor. The laboratory test was performed on laboratory stand for evaluation of drives with PM BLDC motor properties. The laboratory stand was designed for rapid prototyping of BLDC motor control systems. The DS 1104 controller board was used as the main controller of BLDC motor.
13
Content available remote Celowe zwiększanie momentu zaczepowego w bezszczotkowym silniku prądu stałego
EN
In this paper structure of the DC brushless motor with large cogging torque has been presented. Its stator is made of steel sheets used in the small one-phase squirrel cage motor SEMkf-63-4C2/15. Eight-pole, three-phase winding with its bands connecting in star manner is placed in the stator of this motor. The rotor of this motor is a steel cylinder with eight-pole magnet made of N38 material (1,2T and 950 kA/m) glued on its surface. In order to maximalize cogging torque, the stator slots were placed parallely towards pole magnet of rotor. Reflective opto-couplers were used to determine the position of rotor relative to stator. The cogging torque of this motor is equal to 2,16 Nm. Thanks to application of a typical steel sheets of stator and chassis, the motor characterizes the low price.
EN
In the article the results of efficiency simulation research of separately excited motor are presented. Motor drive losses can be reduced by controlling the field current and armature voltage for any torque and speed operating point. All these parameters ara shown as a function of the load torque at work with minimum total losses. The field current is practical independent of speed and based on it can be realized a simple method for loss minimization in d.c. drive. The simulation reaserch are presented at speed: 500,750,1000,1250, 1500 rev/min.
15
EN
In a traditional torus motor, the stator has a slotless winding. If the empty space between the adjacent coils is filled with ferromagnetic material (an iron powder composite or laminated iron), then the magnetic flux density increases significantly. Primarily, this influences the rotor speed (at a given, constant supply voltage), and the electromagnetic torque. To obtain the same speed as for the toothless stator the magnetic flux should be reduced to the previous level by reducing the thickness of the permanent magnets. Otherwise, leaving the increased flux density in the air gap requires that the number of turns in the stator winding has to be reduced. In this paper the authors address the questions concerning what is gained and what effects on the motor performance are achieved if the magnet volume, or the number of turns are reduced after the space between the coils has been filled with magnetic material.
PL
W tradycyjnym silniku typu torus, stojan posiada uzwojenie bezżłobkowe. Jeśli wolna przestrzeń pomiędzy sąsiednimi cewkami wypełniona jest materiałem ferromagnetycznym (kompozyt z proszku żelaza lub pakietowany rdzeń), wówczas indukcja magnetyczna znacząco wzrasta. Ten wzrost ma wpływ głównie na prędkość wirnika (przy określonej, stałej wartości napięcia zasilania), oraz na moment elektromagnetyczny. Aby uzyskać taką samą wartość prędkości co w silniku z bezżłobkowym stojanem, strumień magnetyczny powinien być zmniejszony do poziomu jak w silniku o takim stojanie, poprzez zmniejszenie grubości magnesów trwałych. W przeciwnym przypadku, pozostawiając zwiększoną indukcję w szcze-linie, należy zmniejszyć liczbę zwojów w uzwojeniu stojana. W artykule autorzy stawiają pytanie: co można uzyskać i jaki wpływ na osiągi silnika ma zmniejszenie objętości magnesów i liczby zwojów po wypełnieniu przestrzeni pomiędzy cewkami materiałem magnetycznym.
EN
The method of electromagnetic calculations of brushless DCPM motor formulated as optimisation problem with objective function, which represents the cost of active materials, and flexible set of constraints is presented in the paper. Each constraint can be easily added or excluded from the optimisation problem or can be formulated in the form of equality or inequality. It enables finding an optimal solution using evolution strategy. A limitations which enables direct using of solution procedures included in Optimisation Toolbox for Matlab was taken into account at formulating of the optimisation problem. For exemplary construction of 8 kW motor a series of optimisation calculations with adequate formulated constraints of efficiency and cooling intensity are performed. As a result, a set of noninferior solutions of constructions in form of family of characteristics of minimum cost of active materials or masses, in relation to efficiency and different intensities of cooling is found. Analysis of received set of solutions allows to choose optimum variant of construction of motor from the point of view of minimum costs, maximum efficiencies and suitable intensities of cooling.
EN
Development in a lot of high-tech disciplines opened up wide possibility to use permanent magnet DC motor. Modern magnetic materials based on rare-earth elements, achievements in digital circuit engineering as well as fast power electronic systems allowed on significant improvement of properties of permanent magnet DC motors. For that reason. PMDC motors are used in a lot of technical areas. Unfortunately, torque ripples generated over this kind of motor can not be used in high performance electric drives. In this paper the way of reduction torque-ripples PMDC motor is presented and an effort to determine profiles PMDC motors as well as estimates the influence of magnetic poles shape PMDC motor on the size of the ripple-torque is made. Finite element method has been used to calculate necessary quantities.
18
Content available remote Silniki bezszczotkowe - ograniczenie pulsacji momentu
EN
Proposition of BLDC motor control method, which give possibility of torque ripple minimisation is described in the paper. The control method is modification of classical BLDC motor control strategy. The novel approach, called also over-commutation, is based on earlier switching electronic comutator transistors. The first part of the paper contains theoretical foundations of the method. The simulation research was conducted and the results confirmed correctness of the theoretical considerations. The computer model and selected results are presented in the 2nd chapter of the paper. Finally theoretical assumptions and computer simulations were confirmed by the laboratory verification (chapter 3). The research results lead to the following conclusion: correct application of over-commutation can minimise torque ripple. By using this method it is also possible to increase torque (about 5%÷10%).
19
EN
In this paper a new design of brushless DC motor windings with an internal permanent magnet and electronic switching scheme is presented. These new designs allow motor to achieve speed higher than nominal speed. The motor design is as follows (Fig.2). DC brushless motor contains three different armature winding "phases", each "phase" is further subdivided into two parts. The "phase" origins are supplied from the inverter, and the midpoints are short-circuiting through capacitors C1..C3. In addition, the drive is equipped with the system of electronic switches, which is used for short-circuiting the ends of the armature coils. In still state, when rotating speed is low, current flows mainly through the whole of windings. When speed increases, and the frequency of reload capacitors is large, current flows through an upper part of the windings only. This results in speed increase, similar to that occurring in classic DC motors operating in a standard circuit in "con- stant power range". Switches closing the winding's ends are switched on simultaneously with the switches of higher part of inverter. Therefore the current flowing through a lower part of the windings can not change its polarity The paper presents design of the system, its mathematical model (Fig.4), and transient characteristics (Fig.6, 7. 8) calculated with this model.
EN
The paper presents a modern labour stand for evaluation of motor drives with permanent magnet brushless DC motor properties. The DS 1104 controller board is used as control system of BLDC motor. The labour stand is designed for rapid prototyping of BLDC motor control systems. Using the described equipment it is also possible to evaluate the influence of control method on motor drives properties. The results of measurements are recorded by KPCI 3104 data acquisition board. The last part of the paper presents results of laboratory tests with 300 W BLDC motor compared with computer simulations.
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