contactless position measurement for emc apparatus ocena
Transkrypt
contactless position measurement for emc apparatus ocena
Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Chun Hao Ng, Andrew Nafalski and Özdemir Göl University of South Australia, Mawson Lakes 5095, Australia CONTACTLESS POSITION MEASUREMENT FOR EMC APPARATUS BEZKONTAKTOWY POMIAR POZYCJI W APARATURZE DO BADAŃ KOMPATYBILNOŚCI ELEKTROMAGNETYCZNEJ Abstract: The measurement of radio disturbance power in the frequency range between 30 MHz and 1 GHz is usually conducted using an absorbing clamp. The absorbing clamp assembly that incorporates also a current transformer is moved along the track of the power supply cable and is used to measure electromagnetic interference radiated from the equipment under test (EUT) through its connecting mains cable, to pick up the location of the maximum disturbance and to check the compliance with relevant EMC standards. Manual operation of the clamp is time consuming and tedious, it requires a handdriven advance of the clamp, sealing the screened room, conduction a next test and doing this many times. This paper reports on the development of the remote sensing of an absorber clamp system that has the potential of reducing the EMC test time and increasing its accuracy. An overview of the implementation method and background reasoning is given on the developed system. The EMC emission tests confirm that the position measurement system complies with the EMC norms. Adam Sołbut Politechnika Białostocka, Białystok OCENA STANU UKŁADU NAPĘDOWEGO STEROWANEGO METODĄ ORIENTACJI WEKTORA POLA STATE ESTIMATION OF MOTOR DRIVE USING FIELD-ORIENTED CONTROL METHOD Abstract: Possibilities of inverter-fed motor damages modeling may radically simplify building of on-line working diagnostic algorithms. Choice of those signals and coefficients, on which real-time working algorithms could estimate motor drive’s technical state is an important problem. The way of numerical modeling, based on the original program solution using object C++ programming techniques is presented in the paper. Results of numerical modeling of field-oriented controlled motor drive, including motor damages such as rotor bar braking or rotor eccentricity are included. Effects indicate on the possibility of use of moving RMS current value and flux error signal-based estimation coefficients for on-line diagnostics of a motor drive. Paweł Dybowski, Wacław Orlewski Akademia Górniczo-Hutnicza, Kraków BADANIA GENERATORA INDUKCYJNEGO WZBUDZANEGO KONDENSATORAMI – OBCIĄŻENIE NIESYMETRYCZNE RESEARCH OF INDUCTION GENERATOR EXCITED CAPACITORS – NON-SYMMETRICAL LOAD Abstract: Induction generator can work connected to power system or connected to separated system. Induction machine work can as generator only at this time, when reactive power is delivered to machine. Special selected capacitors were connected to the motor for realization this task. It is possible to use this generator as energy source in small water or wind power plant. Authors call special attention for stabilization of amplitude and frequency of generated voltage. Measurements and time registration for non-symmetrical load are presented in this paper. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Stanisław Azarewicz, Bogumił Węgliński Politechnika Wrocławska, Wrocław BADANIA SILNIKA INDUKCYJNEGO MAŁEJ MOCY PRACUJĄCEGO W CIEKŁYM AZOCIE RESEARCH OF SMALL POWER INDUCTION MOTOR WORKING IN LIQUID NITROGEN Abstract: Results of test of a small power induction motor working in liquid nitrogen are presented in the paper. The motor was designed in such manner to enable flow of the liquid nitrogen inside it. Bearings and design of its rotor were changed to minimize additional mechanical loss. Tests were carried on at feeding the motor from network with sinusoidal voltage and by frequency converter. Results of the motor tests in ambient temperature are presented for comparison reasons. Research was provided due to increasing requirement for equipment for transfer, storage and distribution of liquid gases, which require motors working more often in submerged conditions. Results of the presented research enable assessment of possibilities of applications of typical small power motors to be working as submerged in liquid gases, being dielectrics, as liquid nitrogen at temperature - 1960C and liquid natural gas at temperature – 1610C. Stanisław Azarewicz, Bogumił Węgliński Politechnika Wrocławska, Wrocław PARAMETRY WYBRANYCH BLACH PRĄDNICOWYCH PRZY PODWYŻSZONEJ CZĘSTOTLIWOŚCI PRZEMAGNESOWANIA PARAMETERS OF CHOSEN GENERATOR SHEETS AT ELEVATED FREQUENCY OF REMAGNETIZATION Abstract: Results of research of magnetic and electrical parameters of chosen generator sheets with thickness 0.35 and 0.5 mm, at basic and elevated frequency of remagnetization are presented in the paper. Samples for tests were cut in form of rings with width 10 mm and assembled in toroidal form of height 10 mm, to approximate changes of their parameters to these obtained as results of cutting sheets at manufacture a magnetic core of an electrical motor. To determine influence of sheet insulation on measured parameters, generator sheets covered by various kinds of insulation were tested. The goal of carried out research was assessment of changes of generator sheets parameters, taking into account their applications in motors fed with elevated frequency voltage. Presented research enables quantity and quality evaluation of loss increase, in classic electrical motors fed with voltage generated by frequency converters. Jarosław Guziński, Janusz Szewczyk Politechnika Gdańska, Gdańsk SKŁADOWA ZEROWA PRĄDU W UKŁADZIE ELEKTROWNI WIATROWEJ Z GENERATOREM SYNCHRONICZNYM Z MAGNESAMI TRWAŁYMI ZERO CURRENT COMPONENT IN THE WIND POWER PLANT WITH PERMANENT MAGNET SYNCHRONOUS GENERATOR Abstract: In the rotating electrical machines working with transistorized converters common mode (CM) voltage current appears. The reasons of the CM voltage appearing are inner properties of the transistors control algorithms. When the CM voltage exists the CM current can flow through parasitic capacitance of the electrical machines and converters. Part of that current flows through motor bearing and strongly decreases bearing life. Example of power electronics drive is wind generator system. In the wind generator system two converters are used: machine inverter and grid inverter. In the presented system the permanent magnet synchronous generator (PMSG) was used. For PMSG efficient control the position of the rotor should be known. In the realized drive to eliminate position sensors the sensorless control method was implemented. During realization of the sensorless control the problem with the measurements Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 of the machine voltage appeared. The measured voltage was strongly disturbed by flow of the common mode current. To solve that problem the path the high impedance for CM path was inserted. Two solutions: zero component choke and threephase transformer applied between the generator drive system and the electric grid were tested. In the paper the CM voltage theory is presented. The results of the experimental investigations are presented. Radosław Machlarz Politechnika Lubelska, Lublin BADANIA SYMULACYJNE WŁAŚCIWOŚCI DYNAMICZNYCH SYNCHRONICZNEGO SILNIKA RELUKTANCYJNEGO SIMULATION ANALYSIS OF TRANSIENT STATE PERFORMANCE OF SYNCHRONOUS RELUCTANCE MOTOR Abstract: The paper presents an approach to simulation analysis of synchronous reluctance motor transients by means of indirect field-circuit method. Dynamic performance of two pole synchronous reluctance motor with axially laminated, anisotropic rotor with modified magnetic circuit was investigated. Asymmetrical equivalent rotor damping cage and skin effects in aluminum layers were taking into account. An indirect field-circuit model including frequency dependent parameters of damping circuit was derived and implemented in Matlab/Simulink environment. A series of simulation were performed for different start up parameters (initial voltage, initial frequency, start-up duration), shaft torque step and moment of inertia. The simulation results confirmed good dynamic performance of the motor with modified rotor structure and the reliability of proposed simulation method, although some improvements are still necessary. Zbigniew Damm F.S.E. Besel S.A. , Brzeg JEDNOFAZOWY SILNIK SYNCHRONICZNY RELUKTANCYJNY Z ROZRUCHEM ASYNCHRONICZNYM SINGLE-PHASE SYNCHRONOUS RELUCTANCE MOTOR WITH ASYNCHRONOUS START-UP Abstract: In this paper a new concept of a single-phase reluctance motor with asynchronous start-up is shown. The paper describes a way of evolving of construction to achieve the final successful result. Details of the “hybrid” rotor construction and motor characteristics are shown. The main advantage of these motors are synchronous operation with single-phase supply and simple and cheap motor construction based on a squirrel-cage induction motor. Andrzej Dembowski, Piotr Chudzik, Politechnika Łódzka, Łódź Witold Kobos, ZEP Enika, Łódź OSŁABIANIE STRUMIENIA MAGNETYCZNEGO W TRAKCYJNYCH SILNIKACH INDUKCYJNYCH FIELD WEAKENING IN THE TRACTION AC MOTOR DRIVE Abstract: Selection of the AC motor for traction applications depends strongly on economical reasons. That means, that it is important to keep the dynamical performance of the vehicle as well as possible but the low price of the drive is also required. Usually the compromise in this choice is achieved thanks to the selection of the AC drive nominal parameters corresponding to the middle velocities of the vehicle. Unfortunately, during the motor operation with higher velocities we observe then the lack of the voltage necessary for effective driving. The aim of this paper is to show the procedure of selection of 165kW AC motor for trolley-bus drive. There are given some reasons for choosing of the motor nominal data which do not correspond to the high speed working region. On the example of trolley-bus drive in Lublin it is shown how to adjust the reference frame for demanded flux vector and an algorithm which enables the drive control in the flux weakening region is also described. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Václav Mentlík, Radek Polanský, Pavel Prosr, Josef Pihera University of West Bohemia, Pilsen ACTIVATION ENERGY OF TRANSFORMER OILS ENERGIA AKTYWACJI OLEJÓW TRANSFORMATOROWYCH Abstract: The power transformers are the key components of power grid from the reliability point of view. Due to operation conditions, aging of particular parts of power transformers appears and this fact also causes changes of the important electrical and mechanical properties. Transformer working life is given by a working life of its insulating system. The insulating system of these devices is inseparably composed of the solid (based on cellulose) and oil insulation. Liquid part fulfils besides the insulation also cooling function and the analysis of this part of insulating system during the laboratory thermal aging became the main aim of our experiment. Activation energy was chosen as the main parameter corresponding to the actual condition of insulating oil. Two groups of insulating oils were examined. Three kinds of mineral petroleum-based oils are in the first one (common commercial products – Technol, ITO 100, BTSi); the second group contains three oils based on synthetic esters (Dibutyl phthalate – dibutyl ester of phthalic acid, Dioctyladipate – di(2-ethylhexyl) ester of adipic acid, Diisobutyl adipate – bis(2-methylpropyl) ester of adipic acid). The activation energy was measured by thermogravimetry analysis. Thermal aging process has been still processing due to extensiveness of this project. Meanwhile, the activation energy was analyzed on the samples in virgin state and after 1000, 2000 and 3000 hours of thermal aging at the temperature of 90 °C. Piotr Bogusz, Mariusz Korkosz, Jan Prokop Politechnika Rzeszowska, Rzeszów STANY AWARYJNE MASZYNY RELUKTANCYJNEJ PRZEŁĄCZALNEJ W ZAKRESIE PRACY GENERATOROWEJ FAULTS CONDITIONS OF SWITCHED RELUCTANCE MACHINE FOR GENERATOR MODE Abstract: Switched reluctance machines are a main candidate for applying as the starter/generators in the aerospace and various automotive applications. The choice of SRM for the starter/generator application is dictated mainly with its reliability and fault tolerance of the machine and its electronics. This paper is introducing the problem the functioning of the work of switched reluctance machine (SRM) in generator mode for normal and fault electrical conditions. Authors made classification of damage for switched reluctance machines. Cases of the work of a machine were described in emergency states. Simulation examinations and experimental machines were made for 6/4 SRM construction. Results of simulation and laboratory examinations were included. Conclusions were presented. Piotr Bogusz, Mariusz Korkosz, Jan Prokop Politechnika Rzeszowska, Rzeszów MINIMALIZACJA PULSACJI MOMENTU W SILNIKU RELUKTANCYJNYM PRZEŁĄCZALNYM Z ZASTOSOWANIEM FUNKCJI ROZKŁADU MOMENTU MINIMIZATION OF TORQUE RIPPLE IN SWITCHED RELUCTANCE MOTOR WITH USING OF TORQUE SHARING FUNCTION Abstract: Methods of description of torque sharing functions (TSF) are presented in this work. There are also shown mathematical and simulation models of the SRM. The simulation model is prepared using MATLAB/SIMULINK system. There is used card DS 1104 with digital signal processor (DSP) for laboratory stand. Results of simulation and experimental tests of the switched reluctance motors for two various torque sharing functions are presented and compared here. The first control function is a trapezoidal and second function is with cosine edge. Both functions are used for torque ripple minimization. Presented results of simulation and experimental tests are carried out for the steady states of motor operation. Conclusion is presented. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Andrzej Sikora, Barbara Kulesz Politechnika Śląska, Gliwice ZALEŻNOŚĆ JAKOŚCI ENERGII SIECI TRAKCYJNEJ OD ZASTOSOWANYCH UKŁADÓW TRANSFORMATORÓW PROSTOWNIKOWYCH DEPENDENCE OF TRACTION VOLTAGE QUALITY ON TRANSFORMER-RECTIFIER SYSTEM Abstract: Tram lines in Poland are supplied from the power grid via transformer-rectifier sets, with primary three-phase transformer windings wye- or delta-connected, and secondary side windings connected in accordance with desired number of phases.. The number of pulses in rectified dc voltage depends on transformer used. Supply voltage may be either purely sinusoidal and symmetrical, or it may be distorted, or asymmetrical, or both. The paper presents several different transformer types, which are used or may be used in energy transformation and shows the results of investigating dc traction voltage quality and power grid current quality depending on transformer-rectifier set used and quality of supply voltage. The transformer types analysed are 9-phase, 2x6-phase, 12-phase and, for comparison purposes, 6-phase. The resulting dc waveforms are shown together with results of calculations covering THD vector value for different supply conditions. Results of laboratory tests are presented as well. Interesting effect of 24-pulse system changing into 6-pulse system is marked. Jarosław Kozik Akademia Górniczo-Hutnicza, Kraków ZASTOSOWANIE SIECI NEURONOWYCH W DETEKCJI USZKODZEŃ SILNIKA SYNCHRONICZNEGO ZE ZWARTYM UZWOJENIEM WIRNIKA APPLICATION OF NEURAL NETWORKS IN FAULTS DETECTION OF THE SYNCHRONOUS MOTOR WITH SHORTED FIELD WINDING Abstract: This paper describes an automatic recognition of synchronous motor faults based on spectral analysis of stator and field currents with the aid of neural networks. As the diagnostic object a specially designed and constructed 2-pair pole synchronous machine with two parallel branches containing two groups of coils on each stator phase was used. The ends of every group are accessible allowing different connections to be made thus simulation of various fault conditions to be done. For the purpose of the paper a nineteen different fault conditions were investigated, including alone breaks of one group of coils for each phase, simultaneous breaks of one group of coils for each pair of phases and for all three phases, alone shorts of one group of coils for each phase and combined short and break faults. The spectral analysis of the phase and field currents revealed the frequencies which are representative for a particular fault. The amplitudes relating to these frequencies were then used in automatic process of motor state recognition. The recognition was made by a two different neural networks – one for analyzing the phase currents and the other one for analyzing the field current. Arkadiusz Lewicki, Jarosław Guziński Gdansk University of Technology, Gdańsk DETECTION AND COMPENSATION OF TORQUE HARMONICS IN DRIVE WITH INDUCTION MOTOR AND GEAR WYKRYWANIE I KOMPENSACJA SKŁADOWEJ HARMONICZNEJ MOMENTU W NAPĘDACH Z SILNIKIEM INDUKCYJNYM I PRZEKŁADNIĄ Abstract: In many solutions of drives, the torque transmission systems are used for torque converting from the motor shaft to the load. Properties of torque transmission system are a reason of mechanical vibration occurring in drive system. Analysis of drive vibration, usually measured by the accelerometer, makes it possible to create diagnostic system for detection of mechanical faults of drive. In many applications, an introducing of vibrations to drive system is undesirable. Mechanical vibrations of drive can be reduced by generation of appropriate torque components in electric machine. Proper compensation Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 of mechanical vibration requires information about amplitudes and frequencies of vibration harmonics. In drive system with gear, the reduction of mechanical vibration and early detection of gear damages require information about mutual position of toothed wheel and the torque transmitted by gear. Analysis of state variables of induction motor makes it possible to indicate the instants of toothed wheels meshing. It makes it possible to eliminate both: vibration and optical sensors in systems of detection of gear damages and compensation of mechanical vibration. In this paper a method of sensorless detection of torque ripples, caused by gear transmission, is proposed. Presented method can be use in systems for early detection of gear damages and for active compensation of mechanical vibration. The results of simulation and experimental researches on proposed detection and compensation method are presented in the paper. The experiments were provided for a drive with 10kW induction motor with gear and for a high-speed train drive with gear and 1.2MW asynchronous motor. Jan Anuszczyk, Dariusz Zając Politechnika Łódzka, Łódź ANALIZA PRACY NAPĘDU TRAKCYJNEGO Z SILNIKIEM INDUKCYJNYM ANALYSIS OF WORK OF AN INDUCTION MOTOR TRACTION DRIVE SYSTEM Abstract: In this paper the work of frequency converter voltage as well as the computer simulation of induction motor traction drive has been analysed. Work of the motor analysis was made for the railway traction supplied by the 25 kV, 50Hz alternating voltage. In order to eliminate higher voltage harmonics the used converters system provided output voltage of changeable amplitude, changeable frequency and current with sinusoidal shape. For analysed drive system Matlab/Simulink model was created. In result of simulation, the characteristics of torque, current and speed of the traction motor were studied. Václav Boček, Robert Vik University of West Bohemia, Pilsen MECHANICAL PROPERTIES OF EPOXY/GLASS/MICA COMPOSITE AT HIGH TEMPERATURE WŁAŚCIWOŚCI MECHANICZNE KOMPOZYTU EPOKSYD/SZKŁO/MIKA W WYSOKICH TEMPERATURACH Abstract: The stator windings of large rotating machines are insulated with mica-glass fabric impregnated with epoxy resin. These composites are exposed to thermal, mechanical and electrical stresses. The mechanical behaviour of two different forms (foil and tape) of cured epoxy/glass/mica composite was studied during this experiment. Specimens were made of calcinated mica paper and a glass cloth, bonded together with epoxy-novolac resin. These materials are used for the insulation of coils and bars of the electric machines in thermal insulation class F. The aim of this experiment is to compare the present material with the modified one. The improvement is based on the use of innovated glass cloth and in modification of epoxy-novolac bonding resin. Tensile and bending strength of these materials are investigated at room temperature and at temperatures 130, 155 and 180 °C. Decreasing of tensile strength and bending strength of both materials with increased temperature is shown. Eva Kučerová, Robert Vik University of West Bohemia, Pilsen INFLUENCE OF DICY CRYSTALS ON ELECTRICAL AND MECHANICAL BEHAVIOUR OF THE EPOXY/GLASS COMPOSITE WPŁYW KRYSZTAŁÓW NA WŁAŚCIWOŚCI ELEKTRYCZNE I MECHANICZNE KOMPOZYTU EPOKSYD/SZKŁO Abstract: Epoxy/glass composites are widely used in the manufacture of quite a number of electrical machines and equipment. These composites (epoxy/glass laminates) are frequently prepared from prepregs. The prepregs are made by coating woven glass fabric with an epoxy resin, usually cured to the B-stage. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Dicyandiamide (DICY) is used as a curing agent for the epoxy resin. In usual conditions the curing agent is fully depleted during the curing process. However in undesirable conditions DICY crystallizes and these crystals can adversely affect insulation properties of the material. This paper deals with term specification, when the DICY crystals occur and determination of their influence on mechanical and electrical properties of epoxy/glass laminate. Based on the results is evident that the influence of residual dicyandiamide on electrical properties of epoxy/glass laminate is insignificant. Josef Pihera, Oldřich Tureček, Petr Martínek University of West Bohemia, Pilsen ANALYSIS OF PARTIAL DISCHARGE DETECTED WITH SENSORS OF EMITTED ELECTROMAGNETIC FIELD ANALIZA WYŁADOWAŃ NIEZUPEŁNYCH WYKRYWANYCH CZUJNIKAMI POLA ELEKTROMAGNETYCZNEGO Abstract: Partial discharge measurement and subsequent analyses is one of important and capable test of electrotechnological diagnostics. This test evaluates the properties of electrical insulation system of electrical machines and devices. There are a lot of partial discharge test methods based on physical or chemical detection of partial discharge. The detection of electromagnetic field, produced during partial discharge, with capacitive coupler and subsequent data analysis and representation is one of mentioned diagnostic method. The special software program was created for measured data evaluation. This program converts data stored by digital oscilloscope to more comfortable text formats. The converted data are analyzed by common software Matlab, Statistica, etc. Waldemar Milej Akademia Górniczo-Hutnicza, Kraków WPŁYW ROZŁOŻENIA PRZEWODÓW W ŻŁOBKU STOJANA NA NAGRZEWANIE SILNIKA INDUKCYJNEGO INFLUENCE DISTRIBUTION WIRES IN THE STATOR SLOT OF WINDING HEAT THE INDUCTION MACHINE Abstract: Results of field calculations for a two-dimensional thermal model of induction machine was presented in this paper. Calculations and measurements have been provided for an induction squirrel-cage motor of low power and the following ratings: PN=1.5 kW, 2p=4, fN=50 Hz, UN=3x380 V. A two-dimensional geometric model has been proposed for field calculations and the model has been divided into areas with different physical properties of materials and structure. Within these areas thermal equations (1) have been defined; they use different parameters and were solved with partial differential equations. Two simulation models (Fig. 1.) reduced which consists of a single stator slot and a single rotor slot were discussed in this paper. During simulations, a solution of the thermal model has represented a distribution of temperature increase in the induction machine (Fig. 4 and Fig. 5.) and resistivity functions (Fig. 6). This work has been sponsored in 2008 as AGH University Grant no. 11.11.120.615. Michał Górny Główny Instytut Górnictwa, Kopalnia Doświadczalna „BARBARA”, Mikołów CIŚNIENIE WYBUCHU WE WNĘTRZU OGNIOSZCZELNYCH SILNIKÓW INDUKCYJNYCH W NISKICH TEMPERATURACH EXPLOSION PRESSURE INSIDE FLAMEPROOF ELECTRICAL MOTORS IN LOW TEMPERATURES Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Abstract: This paper presents results of research of low temperature effect for explosion pressure value inside electrical squirrel-cage induction motors. Research were carried out in accordance with PN-EN 60079-1 (IEC 60079-1) for motor mechanical size “250”, “280” and “315” in temperatures +20°C, -20°C, -30°C, -40°C and -50°C. Gas mixtures appropriate for subgroup IIB and IIC (ethylene, hydrogen + methane, hydrogen with air) were applied. Obtained results were related to results of analogous tests carried out for simply construction flameproof enclosure. The analyze of critical elements for values of obtained explosion pressures was made (geometry and dimensions, run of the motor, turbulences and local compression of gas mixture). Andrzej Wnuk Danfoss Sp. z o.o. Napędy Elektryczne, Grodzisk Mazowiecki WDROŻENIE ROZWIĄZANIA ACTIVE FRONT END W PRZETWORNICACH CZĘSTOTLIWOŚCI DUŻYCH MOCY DO 1,2MVA POPRZEZ RÓWNOLEGŁE ŁĄCZENIE STANDARDOWYCH MODUŁÓW FALOWNIKOWYCH DEVELOPMENT OF A 1,2 MVA ACTIVE FRONT END USING PARALLEL INDUSTRIAL UNITS Abstract: Danfoss Drives A/S has developed a 1,2MVA Active Front End (AFE). The purpose was to realize a high power AFE as a study object. The AFE was integrated into a new dynamometer and engaged in testing of high power motor inverters. Because of limited time frames the design had to assure immediate successful operation. That was the reason that standard inverter modules have been used. The article presents the crucial problems we had to cope with when developing the AFE project. Based on the gained experience a few 1,2MVA converters with AFE solution were built and commissioned at the container gantry cranes in a harbour in Africa. Roman Dudek, Stanisław Kosiorowski, Andrzej Stobiecki Akademia Górniczo-Hutnicza, Kraków STANY PRZEJŚCIOWE W FILTRACH WEJŚCIOWYCH NAPĘDÓW TRAKCYJNYCH STEROWANYCH IMPULSOWO PRZY PRACY SILNIKOWEJ I PRĄDNICOWEJ TRANSIENT STATES IN INPUT FILTERS OF PULSE-MODE CONTROLLED TRACTION DRIVES IN MOTORING AND GENERATING MODE OF OPERATION Abstract: Analysis of stable operation conditions of the input filters of the mine locomotives’ drive systems was presented in the paper. Equations describing the drive system in various operation states were formulated on the basis of a simplified model of the traction system. The points of balance were obtained and linearization of the system was carried out using the power series method and Jacobi matrix. Conditions of stable operation concerning the minimum value of the input filter capacitance depending on the parameters of the supply source and traction network and also on the characteristics and operation states of the drive were given. Special attention was paid to the analysis of the stable operation conditions in the generating mode during braking. Selected results of simulation and laboratory tests concerning the stable operation conditions of the input filter of the drive system of the pulse-mode controlled mine locomotive were presented. Laboratory tests were carried out using a laboratory stand equipped with a 45 kW traction motor of the mine locomotive type Ld 31. Zbigniew Goryca Politechnika Radomska, Radom WOLNOOBROTOWY GENERATOR TARCZOWY DO MAŁEJ ELEKTROWNI WIATROWEJ Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 LOW SPEED DISK GENERATOR FOR SMALL WIND POWER STATION Abstract: In this paper, the construction of slow-speed disc generator of small wind power station has been presented. Assumption of low turning speed at the design stage allows for elimination of gear box, what in turn decreases the cost of generator and increases its efficiency. In construction of stator, typical cores of low power transformer have been applied. The rotor is a steel disc with neodymium magnets glued on its surface. In this paper, chosen experimental results showing electrical parameters of generator, advantages and disadvantages of prototype have also been presented Tomasz Lerch Akademia Górniczo-Hutnicza, Kraków WSPÓŁPRACA ELEKTROWNI WIATROWEJ Z MASZYNĄ DWUSTRONNIE ZASILANĄ Z SYSTEMEM ENERGETYCZNYM W WARUNKACH NIESYMETRII NAPIĘĆ WIND TURBINE WITH DOUBLY-FED INDUCTION GENERATOR OPERATION IN UNBALANCED ELECTRIC POWER SYSTEM Abstract: This paper shows results of simulation investigations of wind turbine with doubly-fed induction generator operation in unbalanced electric power system. The aim of presented research was analysis of impact of network events on the wind power plant mechanical system. In order to realize the investigations a dynamic mathematical model of wind power plant has been created. The model allows for mechanical system of power plant, rotor-side electronic power converter, slipring machine and control system. The transmission and the turbine have been modeled as a six mass oscillator reduced to the generator shaft. The study results show that voltage unbalance and short-term voltage dips cause torque surge on the shaft and transmission of the wind power plant. A modification of method of active power control has been proposed in order to reduce the impact load of the mechanical system. The results of simulations of wind power plant transients with modified control system are quite promising: a reduction of impact load of mechanical system up to 72% has been reached. Janusz Flasza Politechnika Częstochowska, Częstochowa MODELOWANIE W BUDOWIE I EKSPLOATACJI MASZYN ELEKTRYCZNYCH MODELING IN CONSTRUCION AND EXPLOITATION OF ELECTRIC MACHINES Abstract: Modeling in construction and exploitation of electric machines has essential influence on efficiency all of real electro-machine system. Development of proper model is tied for electromechanical systems with project design of electric engine operational methods and prognostic solutions for modern driving matches as well as with diagnostics according to model. Konrad Dąbała Instytut Elektrotechniki, Warszawa HAMOWNICE PRĄDU STAŁEGO I PRZEMIENNEGO ZE ZWROTEM ENERGII DO SIECI DIRECT AND ALTERNATING CURRENT DYNAMOMETERS WITH THE ENERGY RETURN INTO THE MAIN Abstract: In the paper were done some comparative tests of direct and alternating dynamometers with power-electronic device witch has possibility of returning energy to the main. There were used three types of motors witch had near the same Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 rated torque and different speed. As criteria of the evaluation were used the values of stray load losses (method B), the dispersion of measured points, the fluctuation of tested motor input power and the shape of the current returned into the main. The measurements of torque were made by three devices a torque-meter, a force sensor and an electronic scale. There were presented the results of the tests, analysis of this results, conclusion, advantages and disadvantages of the devices. Tomasz Kubera PKN Orlen S.A., Płock WPŁYW TOPOLOGII OBWODU WEJŚCIOWEGO PRZEMIENNIKA CZĘSTOTLIWOŚCI DUŻEJ MOCY NA PARAMETRY MOCY POBIERANEJ Z SIECI ZASILAJĄCEJ INFLUENCE OF THE HIGH POWER FREQUENCY CONVERTER INPUT PART ON CONSUMING POWER PARAMETERS Abstract: Nowadays in Industry we observe commonly implemented 6, 12, 18 pulse topologies for input units of High Power Frequency Converters. Also more and more we can meet Active Front End solutions with active rectifier unit. In this article we show diagrams of recorded input currents and input voltages flows for 6,12,18 pulse and AFE input topologies of similar nominal power frequency converters (ca 800kW drives for water pumps). Recordings have been made in real industrial circumstances at different load steps to perform THDI distortion factor calculations. We expect, that results of these calculations will allow us to decide , what topology should be recommended for new High Power Variable Speed Drive solutions. Mirosław Dąbrowski, Andrzej Rudeński Instytut Elektrotechniki, Warszawa OPROGRAMOWANIE DO PROJEKTOWANIA SILNIKÓW INDUKCYJNYCH WYSOKOOBROTOWYCH SOFTWARE FOR HIGH-SPEED INDUCTION MOTORS DESIGN Abstract: In the introductory part of the paper a application review and achievements outline of high speed motors from the beginning of applying, i.e. from 40 years of XX century are presented. Then the attention was directed on issues concerning structure of high speed motors and additional phenomena connected with supplying from high frequency voltage source, i.e. mechanical stresses; skin effect; power losses and their increasing caused by non-sinusoidal shape of supplying voltage. The extends and supplements of calculation algorithm and computation program concerned: mechanical power losses calculations (friction and windage losses), calculations of winding resistances and reactances by increased frequency and air gap thickness are presented. Moreover are presented the general technological requirements connected with start of motors production in examined rated power and rotation speed range. The software presented in the paper enabled high speed motors calculations of rated power up to 100 kW. As an example the calculations are performed for five two-pole motors of synchronous rotating speed 18 000 rpm, i.e. of supply voltage frequency 300 Hz. Wojciech G. Zieliński Politechnika Lubelska, Lublin WYZNACZANIE PRĄDU ROZRUCHOWEGO I MOMENTU ROZRUCHOWEGO DLA SILNIKÓW ASYNCHRONICZNYCH DETERMINATION OF STARTING CURRENT AND STARTING TORQUE FOR ASYNCHRONOUS MOTORS Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Abstract: Calculation of the starting parameters for three-phase asynchronous motors is a very important issue as these parameters determine whether a motor can be satisfactorily used in a driving system and characterize it from the point of view of supply mains. The article discusses methods of determining initial starting current and initial starting torque with the omission of issues connected with electromagnetic transient processes, the influence of thermal states, and the effect of parasitic torques. Direct determination of these parameters is relatively complex, which is why they are often determined in an indirect way. Two methods are described, which allow to establish the aforementioned parameters: the tangent method and the short-circuit reactance distribution method. The methods consist in an extrapolation of short circuit characteristics obtained at reduced voltage. The results of research and the comparison of parameter calculations refer to two induction motors: squirrel cage and slip ring. Wojciech G. Zieliński, Maria J. Zielińska, Włodzimierz Zieliński Politechnika Lubelska, Lublin WYKORZYSTANIE METODY POŚREDNIEJ DO OKREŚLANIA MOMENTU KRYTYCZNEGO SILNIKA INDUKCYJNEGO INDIRECT METHOD APPLIED TO DETERMINE PULL-OUT TORQUE FOR INDUCTION MOTORS Abstract: Pull-out torque and the corresponding pull-out slip of induction motors is determined, with a fair degree of accuracy, by measurements in the short-circuit and idle-running states. This refers to motors without the skin effect in the cage bar or those in which the phenomenon has been omitted. The paper compares analytical methods for determining pull-out torque based on the method of equivalent graphs and a simplified Kloss formula. The analysis was carried out for two induction motors: squirrel cage and slip ring. Pull-out slip and torque diagrams were used. An advantage of this method is the fact that determination of pull-out torque does not require the knowledge of pull-out slip. Maria J. Zielińska, Wojciech G. Zieliński Politechnika Lubelska, Lublin METODA WYZNACZANIA REZYSTANCJI WIRNIKA Z UWZGLĘDNIENIEM WYPIERANIA PRĄDU DLA SILNIKÓW SZYBKOOBROTOWYCH A METHOD FOR ROTOR RESISTANCE DETERMINATION IN HIGH-SPEED MOTORS WITH skin effect TAKEN INTO ACCOUNT Abstract: High speed motors are supplied with 400-1500Hz frequency voltage. They operate in special conditions and have a structure and properties that differentiate them from classic machines. In particular, they are distinguished by the high frequency of supply voltage, intensive cooling introduced to reduce the size of the motor, and closed rotor slots used to minimize vibrations and noise. In the discussed motors, the closed rotor slot was replaced with an open slot due to saturation of the magnetic circuit by the slot leakage flux. The resistance increase coefficient for rotor cage bar as a function of current flowing through the bar was estimated and then total rotor resistance was determined. Subsequently, the resistance calculated on the basis of geometric dimensions with skin effect taken under consideration was verified against results obtained from measurements. It was proved that short-circuit resistance is not a constant and depends on the value and frequency of current. It also includes a component which derives from additional losses occurring in solid construction elements and in rotor cage bars. The paper also presents descriptions showing changes in short-circuit resistance as a function of the motor’s current determined on the basis of measurements with parametrically variable frequency. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Emil Król, Robert Rossa BOBRME Komel, Katowice PRĄDNICE SYNCHRONICZNE Z MAGNESAMI TRWAŁYMI UMIESZCZONYMI WEWNĄTRZ WIRNIKA INTERIOR PREMANENT MAGNEST SYNCHRONOUS GENERATORS Abstract: In the paper two kinds of permanent magnet synchronous generator constructions are compared. The first one is generator with the arc-segment permanent magnets mounted on the rotor surface (Surface Permanent Magnet – SPM construction). The second one is generator with the block-segment permanent magnets mounted inside the rotor’s laminated core (Interior Permanent Magnet – IPM construction). The results of laboratory tests for both kinds of generators operating stand-alone are presented and discussed. It can be concluded from these test results and discussions, that IPM generator is characterized by a lower voltage variations and higher efficiency in the entire range of loads. It is also characterized by higher mechanical strength and higher reliability comparing to the SPM construction. Marian Noga, Akademia Górniczo-Hutnicza, Kraków Lesław Gołębiowski, Marek Gołębiowski, Damian Mazur Rzeszów Institute of Technology, Rzeszów 3D FEM MODEL OF THE INDUCTION MACHINE – CALCULATING AXIAL FLUX MODEL MES 3D MASZYNY INDUKCYJNEJ – OBLICZANIE STRUMIENIA OSIOWEGO Abstract: A 3D model reflecting entire internal structure of the asynchronous machine using finite elements method, has been presented here. Nodal finite elements have been used to approximate scalar potential and edge finite elements to approximate vector magnetic potential. This model includes both the skew of the rotor bars as well cross current flowing through the rotor iron laminates. The three-phase stator winding is supplied with four-lead mains voltage. The axial flux was calculated by integration of the vector potential around the shaft of the machine. Plots were calculated following the switching on the machine at various speeds. Bar as well as ring fractures were simulated. The simulation results have been confirmed by the theoretical anticipations. Stanisław Rawicki Politechnika Poznańska, Poznań ENERGOOSZCZĘDNE STEROWANIE SILNIKÓW NAPĘDOWYCH TRAMWAJU Z UWZGLĘDNIENIEM SYGNALIZACJI ŚWIETLNEJ ZAKŁÓCAJĄCEJ PŁYNNOŚĆ RUCHU POJAZDU ENERGY-SAVING CONTROL OF TRAM DRIVING MOTORS TAKING INTO ACCOUNT LIGHT SIGNALLING DISTURBING SMOOTHNESS OF VEHICLE TRAFFIC Abstract: The paper deals with problems of the tram vehicle control in accordance with the criterion of the minimum electrical energy consumption. In this elaboration, the energy-saving control of the tram driving electric motors takes also into consideration the influence of cross-roads light signalling disturbing the smoothness of the vehicle traffic. In general, the light change during the tram running is here treated as the ride perturbation. Relations describing the tram traffic contain nonlinearities as a result of properties of motion resistances and owing to the magnetic circuit saturation in the motors. Determination of the run algorithm ensuring minimization of the electric energy consumption has been realized by application of the numerical method of differential equations solving and by using the optimization procedure. Calculation Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 process takes many constraints into account, for example the adhesion effect connected with existence of a limiting force acting in the wheel circumference. Within perturbations caused by light signalling, computations of the tram energy-saving run were connected with the algorithm of the delay liquidation. In the case of greater time lags of the traffic, the ride delay must be liquidated during the run between some succeeding stops. Also here the best control strategy can ensure the electrical energy saving. Robert Rossa, Emil Król BOBRME Komel, Katowice METODA OBWODOWO-POLOWA OBLICZANIA CHARAKTERYSTYK ZEWNĘTRZNYCH PRĄDNIC SYNCHRONICZNYCH Z MAGNESAMI TRWAŁYMI PRACUJĄCYCH SAMOTNIE NA ODBIORNIKI TYPU R LUB RL FIELD-CIRCUIT ANALYSIS OF LOAD CHARACTERISTICS OF STAND-ALONE PM SYNCHRONOUS GENERATOR CONNECTED TO “R” OR “RL” TYPE LOAD Abstract: This paper deals with the field-circuit method to calculate the load characteristics of a stand-alone permanent magnet synchronous generator (PMSGen) connected to R-L type load. This method is based on the so-called loading method [1] ÷ [3], used widely for calculation of lumped parameters of permanent magnet synchronous motor’s (PMSM) equivalent circuit model. In the developed calculation algorithm, the circuit equations of PM synchronous machine are adopted so to represent the generative mode of stand-alone operation with the assumption that load is purely of R-L type. The iterative calculation of voltage phasor V1 phase angle is used to find the appropriate values of output voltage and current magnitudes for a given power factor cosϕ and for given output power. Marek Kacperak Cementownia „Odra”S.A., Opole UTRZYMANIE RUCHU UKŁADÓW NAPĘDOWYCH W PRZEMYŚLE CEMENTOWYM MAINTENANCE OF ELECTRIC DRIVE SYSTEMS IN CEMENT INDUSTRY Abstract: This short document describes represents question about maintenance of electric drive system. Industrial plant which they work in continuous system they require different way of repairs. Preventive working are important element in work of plant. Qualification of technical state of machines lies out the directions of repairs and observation. Every element of driving system should possess supervisory apparatus. Author represents his working for assurance of correct work of devices. The task of maintenance was introduced for one-line and off- line. Włodzimierz Zieliński Politechnika Lubelska, Lublin ZASTOSOWANIE SZTUCZNYCH SIECI NEURONOWYCH DO REDUKCJI STOPNIA ISKRZENIA W ELEKTRYCZNYCH MASZYNACH KOMUTATOROWYCH PRĄDU STAŁEGO APPLICATION OF ARTIFICIAL NEURAL NETWORKS TO REDUCE THE LEVEL OF SPARKING IN ELECTRIC DIRECT CURRENT COMMUTATOR MACHINES Abstract: The paper presents a possible application of the capabilities of methods and techniques of ANN artificial intelligence for diagnostics of sparking processes in electric direct current commutator machines. Hitherto applied methods of diagnostics, usually based on the visual observation of sparking, depend on the expert’s knowledge and experience. The expert interprets current data obtained from observation. The drawback of this approach lies in its dependence on the expert’s Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 knowledge and experience, which makes the data difficult to use for further processing. That is why, apart from improving methods, it is necessary to find a way to objectify the sparking processes in the detection and assessment of damage as well as reduction of the level of sparking of brushes. Włodzimierz Zieliński Politechnika Lubelska, Lublin KONCEPCJA SYSTEMU EKSPERTOWEGO MONITOROWANIA I DIAGNOSTYKI ELEKTRYCZNYCH MASZYN KOMUTATOROWYCH PRĄDU STAŁEGO A CONCEPT OF AN EXPERT SYSTEM FOR MONITORING AND DIAGNOSTICS OF ELECTRIC DIRECT CURRENT COMMUTATOR MACHINES Abstract: The paper presents a concept of realization of an expert system for monitoring and diagnostics of electric direct current commutator machines. A perceptron regulator of the current of commutation poles is sometimes incapable of eliminating or reducing the sparking of brushes. This may be due to mechanical or other additional factors, which were not taken into consideration in the process of instruction of the artificial neural network ANN described in the previous paper. That is why the application of a damage detector will allow to control states of emergency or machine failures and to inform the system operator or shut down. Janusz Bialik, Jan Zawilak Politechnika Wrocławska, Wrocław DRGANIA WŁASNE KONSTRUKCJI DWUBIEGOWEGO SILNIKA SYNCHRONICZNEGO FREE VIBRATION ANALYSIS OF THE TWO-SPEED SYNCHRONOUS MOTOR Abstract: In this article the free vibration’s calculation method, of the electrical motors with very complicated structure, are presented. An example of such machines are a two-speed synchronous motors. Calculation were done using two- and three dimensional FEM models. The aim of this paper is a presentation of the calculation results of the motor type GAe1510/12p which has two different rotational speeds: n=500 rpm (2p=12) and n=600 rpm (2p=10) and appertaining powers: P=600 kW and P=1050 kW. Results of the presented analysis are the next step in understanding problems existing in such motors, i.e. electromagnetic noise or vibration of electromagnetic origin. Piotr Kisielewski, Ludwik Antal Politechnika Wrocławska, Wrocław OBWODY TŁUMIĄCE TURBOGENERATORA OBCIĄŻONEGO NIESYMETRYCZNIE DAMPER CIRCUITS IN TURBOGENERATOR FOR ASYMMETRY LOAD Abstract: This paper presents two-dimensional field-circuit model of 500 MVA turbogenerator. Model is designed to calculate static and dynamic characteristics of machine. During solving field equations real physical characteristics of materials, configuration of windings, damper circuit and motion elements in electromagnetic field are taken into account. In circuit part there is an electrical scheme. The electrical elements correspond with winding in the field model. Parameters of frontal connections are included. The model was applied to calculate damper winding currents in active and front parts in case of appears asymmetry in power system. Currents distribution and flux lines for the asymmetry work was calculated too. Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 Using the model of turbogenerator it is possible to calculate flux and current densities, field distributions and other physical quantity for every time step of simulation. Tomasz Mnich Politechnika Śląska, Gliwice OCENA MOŻLIWOŚCI ZASTOSOWANIA OKREŚLONEGO SCHEMATU CIEPLNEGO SILNIKA INDUKCYJNEGO W SZERSZYM ZAKRESIE MOCY ZNAMIONOWYCH ASSESSMENT ABILITIES MAKE USE THE SPECIFIC THERMAL EQUIVALENT DIAGRAM OF INDUCTION MOTOR ON BROADER RANGE OF NOMINAL POWER MOTORS Abstract: The paper presents assessment abilities make use the basic and three simplifies thermal equivalent diagram of induction motor to monitoring temperatures on broader range of nominal power induction motors. In article discussed assumption form construction thermal equivalent diagram, and possibility make us them to monitoring temperature of induction motor. The monitoring of heating of induction motor is presented for example two motors, on power 3 kW and 18,5 kW. Presents verification measurements increase temperatures in 3 kW and 18,5 kW induction motor on measurements station. Precision of computer simulations was compare with basing thermal equivalent diagram – verifying in laboratory measurements In the end of paper author presents conclusion from computer simulation and laboratory measurements, who was application this method in practical application and what are the limits of power motors to make us the same thermal equivalent diagrams. Stanisław Gawron BOBRME Komel, Katowice PRĄDNICA SYNCHRONICZNA Z MAGNESAMI TRWAŁYMI O PODWÓJNYM WIRNIKU ZWIĘKSZAJĄCA CZĘSTOTLIWOŚĆ GENEROWANEGO NAPIĘCIA TWO-STAGE PERMANENT MAGNET SYNCHRONOUS GENERATOR INCREASING OUTPUT VOLTAGE FREQUENCY Abstract: This paper presents the construction of a model, two-stage low speed synchronous generator designed for producing energy from the renewable sources. More over, the computational methodology and the basic results of electromagnetic calculations of the two-stage low speed synchronous generator with permanent magnets are presented. On the basis of the calculations conducted, a physical model of the generator was made, on which the preliminary laboratory tests were carried out. There is also a comparative record sheet of the preliminary laboratory tests and the results of the theoretical calculations included in the paper. Adrian Mrozek Politechnika Śląska, Gliwice PRÓBA WYZNACZENIA PARAMETRÓW ZNAMIONOWYCH BEZSZCZOTKOWYCH SILNIKÓW SYNCHRONICZNYCH WZBUDZANYCH MAGNESAMI TRWAŁYMI ATTEMPT OF RATING DETERMINATION OF BRUSHLESS PERMANENT MAGNET SYNCHRONOUS MOTOR Abstract: The paper presents the results of measurements of brushless permanent magnet synchronous motors (PMSM) and the methodology of the rating determination. The PMSM have two different rotor construction. The first one has a surface Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 mounted block magnets, while the second has radial embedded magnets in the rotor yoke. All the PMSM motors are based on a stator from the small power asynchronous motor. The investigated motors are supplied by the sinusoidal voltage sources during the test. The characteristics of the armature current versus the load torque for the several values of supply voltages are measured. The characteristics of the armature current versus the supply voltage for the several values of the load torque are measured, as well. During the tests temperature in several points of motor were measured. The motor performances were determined in thermal steady state. The temperature distribution on the motor casing were measured by the thermal camera. Emil Król BOBRME Komel, Katowice SILNIKI Z MAGNESAMI TRWAŁYMI ORAZ SILNIKI INDUKCYJNE – CZYNNIKI OBNIŻAJĄCE SPRAWNOŚĆ PERMANENT MAGNET SYNCHRONOUS MOTOR AND INDUCTION MOTOR - FACTORS DECREASING THE EFFICIENCY Abstract: The paper details with a comparison of an energy effectiveness of induction motors and permanent magnet synchronous motors. The causes of loss generation in different types of electric motors and possibilities of their reduction are distressed. Losses and energy effectiveness of electric motor are parameters and quantities in which the user is interested directly because these quantities have the huge impact one the technical and economical parameters of motors. In the paper, two water-cooled mining motors with the nominal power of about the 85kW and with identical overall dimensions are described and compared regarding their energy effectiveness. The first these motors is an induction motor with efficiency η = 92.6% and the second one is the interior permanent magnet synchronous motor (IPM) with efficiency η= 95.8%. It can be deduced from the presented calculation results, that by the use of permanent magnet motors the efficiency of drives can be increased significantly. Tadeusz Glinka, Wiesław Tomaszkiewicz BOBRME Komel, Katowice SILNIKI TARCZOWE DISC MOTORS Abstract: Two types of disc motors are investigated in the paper: - with salient poles, where armature core is made of ferromagnetic steel, as shown in Fig.1, - with coreless armature and two-layer winding as shown in Fig.4. Dependence of rotating torque on number of pole pairs p and ratio of inner diameter d to outer diameter D (β=d/D) has been determined for salient-pole motors (Fig.3). Basing on these characteristics, the motor’s rated power has been calculated depending on motor’s dimensions. The results are set out in Table 1. In case of coreless armature motor the basic dependencies between motor dimensions and electromechanical parameters have been given. Using these relations, armature dimensions have been calculated for 3 kW, 180 V, 2000 rpm motor. The described methodology of calculating armature magnetic circuit dimension and winding data constitutes first design phase of disc motor. During second design phase the motor should be optimised and its magnetic circuit calculated e.g. by some field method. Tomasz Zawilak Politechnika Wrocławska, Wrocław ROZRUCH SILNIKÓW DUŻEJ MOCY PRĄDU PRZEMIENNEGO PRZY ROZDZIELONYCH UZWOJENIACH STOJANA PART WINDING STARTING OF LARGE POWER AC MOTORS Abstract: A concept of part-winding starting of high power induction motors is presented. During the start up some of the parallel branches are directly supplied from a power network whereas the residual branches are disconnected. After start up of Zeszyty Problemowe – Maszyny Elektryczne Nr 80/2008 the motor all branches are fed in parallel. Calculated with FEM torque-speed characteristics for the selected connecting configurations are attached. Transients of torque, speed and current during start up are also presented. Piotr Zientek, Roman Niestrój Politechnika Śląska, Gliwice WPŁYW USZKODZEŃ KLATKI WIRNIKA I NASYCENIA RDZENIA NA WARTOŚĆ NAPIĘĆ WAŁOWYCH W SILNIKACH INDUKCYJNYCH INFLUENCE OF SQUIRREL CAGE FAULTS AND CORE SATURATION ON SHAFT VOLTAGE VALUES IN INDUCTION MOTORS Abstract: The paper presents initial results of laboratory investigations. These results emphasize the intensification of the phenomena connected with bearing currents flow at different rotor cage damages. In the section 2 on the figure 5 are presented results of investigations connected with inducing of the third harmonic of the motor EMF. In the section 3 is presented the influence of rotor cage damages on the shaft voltage value. The subject of these studies was a low power induction motor (fig. 6), taking into consideration easiness and low costs of necessary modernization of it. On the figure 7 is presented the diagram of the shaft voltage and current measurement system. The measurements results are presented on the figure 8. Conclusions drawn from laboratory researches are presented in chapter 4. Tomasz Rudnicki Politechnika Śląska, Gliwice POJAZDY Z SILNIKAMI ELEKTRYCZNYMI MOTOR VEHICLES WITH ELECTRIC MOTOR Abstract: The paper presents advantages and disadvantages of motor vehicles with electric motor. The paper discusses kind of electric motors and shows the methods of regulation circuits of electric motors. Estimate range and travel expenses of vehicles with electric motor are also presented in the paper. Traveling costs are compared for the internal-combustion engine and electric motor. The paper also discusses control method and shows the troubles of regulation circuits of electric motors. Henryk Borecki Energokonsulting, Lubliniec NIESZCZELNOŚĆ PRZEWODÓW ELEMENTARNYCH GENERATORÓW 200 MW Streszczenie: W naszej Energetyce nadal podstawową maszyną prądotwórczą jest generator 30 żłobkowy, produkowany w kraju, w drugiej połowie 20 wieku, na wymuszonej dokumentacji ZSRR. Od pierwszych lat eksploatacji maszyny te były modernizowane zwłaszcza przez firmę remontową /i produkcyjną też/. Nieszczelności stojana w układzie chłodzenia bezpośredniego były i są nadal. Z tą wszak różnicą, że dawniej przypadki postoju bloku były spowodowane nieszczelnością na połączeniach wodnych rozbieralnych a dzisiaj coraz częściej mamy do czynienia z uszkodzeniami elementarnymi przewodów drążonych ze stali lub miedzi. W referacie będą omówione zagadnienia bezpośrednich i pośrednich przyczyn nieszczelności i propozycje z uzasadnieniem wykonania konstrukcji uzwojenia 60 żłobkowego we wszystkich tradycyjnych korpusach TWW – 200-2.