• Title, Summary, Keyword: High speed application

Search Result 1,504, Processing Time 0.039 seconds

Microprocessor Based Sensorless Speed Control of Permanent Magnet Synchronous Motor (마이크로프로세서를 이용한 영구자석 동기전동기의 센서리스 속도제어)

  • 최재영;김성환;권영안
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.20 no.3
    • /
    • pp.121-130
    • /
    • 1996
  • Permanent magnet synchronous motor is widely used in industrial drive applications due to high efficiency, high power ratio, and easy maintenance. Position and speed detectors required in this motor increase the drive cost, and reduce the application range. Some papers present the speed control without position and speed detectors using DSP characterized by high processing performance. However, DSP increases the cost, and makes the inplementation difficult. This study has performed the speed control without position and speed detector by means of the microprocessor system which can be easily accessed. The results of simulation and experiment showed comparatively good dynamics in spite of the sensorless system.

  • PDF

Development of Foil Journal Bearing for Turbo Machinery (터보기기용 포일 저널 베어링 개발)

  • Kim, Kyeong Su;Lee, Ki Ho;Kim, Seung Woo
    • 유체기계공업학회:학술대회논문집
    • /
    • /
    • pp.475-481
    • /
    • 2001
  • Foil bearings have been successfully used for small high speed rotors, such as ACM(Air Cycle Machine), turbo charger, turbo compressor, high speed motor, etc. Recently advanced researches are concentrated on the high load capacity and the extreme temperature foil bearings to extend the application boundary. Some bearings are already adopted into cryogenic machines and micro gas turbines. In this paper, a foil journal bearing designed for high load capacity, which is under development, is introduced. The bearing is for the turbo refrigerator which has a rotor of 18${\~}$25 kgf rotating at 23,000${\~}$38,000 rpm. This application is well beyond conventional spectrum of foil bearings because the rotor is relatively heavy and the rotational speed is low. Therefore, the development is challenging. The foil bearing is a bump type, the size is 60mm in diameter and 50mm in length, the operating fluid is air and rotational speed is 26,000 rpm. In-house software was developed and used for bearing design. Tested maximum load capacity is 80kgf, 0.62 in terms of load capacity coefficient, and testing is being continued.

  • PDF

Development and Application of Computer Aided Systems Engineering Processes for Next Generation High Speed Railway Train -Focus on Requirement Management Structure and PBS Management Structure- (차세대 고속전철시스템 개발을 위한 시스템 엔지니어링 체계 구축 -요구사항 관리체계와 PBS 관리체계를 중심으로-)

  • 유일상;박영원
    • Journal of the Society of Korea Industrial and Systems Engineering
    • /
    • v.25 no.4
    • /
    • pp.22-31
    • /
    • 2002
  • A high-speed rail system represents a typical example of large-scale multi-disciplinary systems, consisting of subsystems such as train, electrical hardware, electronics, control, information, communication, civil technology etc. The system design and acquisition data of the large-scale system must be the subject under strict configuration control and management. Not only the requirements of the large-scale system dictate the contracts with the suppliers but also become the basis for the development process, project execution, system integration, and testing. The requirements database provide the system design specification of all development activities. Using the RDD-100, a systems engineering tool, the Korea next-generation high-speed rail program can establish requirements traceability and development process management in performing the enabling train technology development projects. This paper presents the results from a computer-aided systems engineering application to the Korea next-generation high-speed railway project. Especially, the focus of the study was on requirement management and PBS(Product Breakdown Structure) management.

Sensorless Fuzzy Direct Torque Control for High Performance Electric Vehicle with Four In-Wheel Motors

  • Sekour, M'hamed;Hartani, Kada;Draou, Azeddine;Allali, Ahmed
    • Journal of Electrical Engineering and Technology
    • /
    • v.8 no.3
    • /
    • pp.530-543
    • /
    • 2013
  • This paper describes a control scheme of speed sensorless fuzzy direct torque control (FDTC) of permanent magnet synchronous motor for electric vehicle (EV). Electric vehicle requires fast torque response and high efficiency of the drive. Speed sensorless FDTC In-wheel PMSM drives without mechanical speed sensors at the motor shaft have the attractions of low cost, quick response and high reliability in electric vehicle application. This paper presents a new approach to estimate the speed of in-wheel electrical vehicles based on Model Reference Adaptive System (MRAS). The direct torque control suffers in low speeds due to the effect of changes in stator resistance on the flux measurements. To improve the system performance at low speeds, a PI-fuzzy resistance estimator is proposed to eliminate the error due to changes in stator resistance. High performance sensorless drive of the in-wheel motor based on MRAS with on line stator resistance tuning is established for four motorized wheels electric vehicle and the whole system is simulated by matalb/simulink. The simulation results show the effectiveness of the new control strategy. This proposed control strategy is extensively used in electric vehicle application.

Characteristics Evaluation of Spindle Thermal Displacement with kinds of Lubrication Oil (윤활유 종류에 따른 주축 열변위의 특성 평가)

  • 강순준;이갑조;김종관
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • /
    • pp.93-98
    • /
    • 2003
  • High speed precision machines have been introduced to the CNC industry in order to improve productivity, shorten the appointed date of delivery and reduce the prime cost. High speed machines have more functions then general machines, and they were proved in performance. The production and sales of the high speed machines have been increased not only in domestic market but also all over the world. Accordingly, machines are faster, there are lots of problems to be solved. One of the most difficult problems is the thermal displacement on the main spindle due to generated heat while the spindle is rotated in high speed. Since the thermal displacement directly effects the quality of the machined parts, utmost efforts to minimize the thermal displacement have to be given from the beginning of designing machines. In practice, variety of methods are attempted and practiced to minimize the thermal displacement such as design of symmetrical frame, adoption of high speed bearings, application of compensation system using non-contact sensor and use of forced circulating lubrication system with oil cooler. Even if these variable methods have been practically used in the industrial field, generated heat has not been Perfectly Prevented lienee, in this paper, the characteristics of thermal displacement were investigated when several kinds of oil were tested for a high speed machine with forced circulating lubrication system within the same atmosphere and under the same conditions.

  • PDF

Numerical Flow Simulations Around High Speed Train Using CHIMERA Grid Technique (CHIMERA 격자기법을 이용한 고속전철 주위의 전산유동해석)

  • Choi S. W.;Kim I. S.
    • Journal of computational fluids engineering
    • /
    • v.1 no.1
    • /
    • pp.81-87
    • /
    • 1996
  • The aerodynamic charateristics of high speed train can be improved by well-designing of its fore-body shape. In this paper, as a way of the design a fore-body shape which has optimal aerodynamic charasteristics, 9 models of fore-body shapes are proposed and the change of aerodynamic charateristics is studied through calculations of flow field around high speed train for each fore-body shape. The flow field around high speed trains are calculated using Thin-Layer Navier-Stokes equation and Chimera grid technique. The application of Chimera grid technique to these flow calculations over high speed train which has ground plane under the train makes grid generation easily. As a computaional algorithm, Pulliam and Chaussee's Diagonal algorithm, the modified form of the Beam and Warming's AF scheme which operates on block-tridiagonal matrices, is selected to reduce computaional time. Introducing hole points flag concept to this Diagonal algorithm. a algorithm for Chimera grid is generated. The variational trends of aerodynamic characteristics are studied from the results of flow calculations around high speed trains for 9 fore-body shapes.

  • PDF

Characteristics Evaluation of Spindle Thermal Displacement with kinds of Lubrication Oil (윤활유 종류에 따른 주축 열변위의 특성 평가)

  • 강순준;이갑조;김종관
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.13 no.2
    • /
    • pp.47-53
    • /
    • 2004
  • High speed precision machines have been introduced to the CNC industry in order to improve productivity, shorten the appointed date of delivery and reduce the prime cost. High speed machines have more functions then general machines, and they were proved in performance. The production and sales of the high speed machines have been increased not only in domestic market but also all over the world. Accordingly, machines are faster, there are lots of problems to be solved. One of the most difficult problems is the thermal displacement on the main spindle due to generated heat while the spindle is rotated in high speed. Since the thermal displacement directly effects the quality of the machined parts, utmost efforts to minimize the thermal displacement have to be given from the beginning of designing machines. In practice, variety of methods are attempted and practiced to minimize the thermal displacement such as design of symmetrical frame, adoption of high speed bearings, application of compensation system using non-contact sensor and use of forced circulating lubrication system with oil cooler. Even if these variable methods have been practically used in the industrial field, generated heat has not been perfectly prevented. Hence, in this paper, the characteristics of thermal displacement were investigated when several kinds of oil were tested for a high speed machine with forced circulating lubrication system within the same atmosphere and under the same conditions.

Technical Trend of High Speed Camera (고속 카메라 기술 동향)

  • Park, Doo-Jin;Noh, Young-Hwan;Kim, Tae-Hyung;Lee, Hyo-Keun
    • Current Industrial and Technological Trends in Aerospace
    • /
    • v.6 no.2
    • /
    • pp.125-132
    • /
    • 2008
  • High speed camera is very important and essential device to analyze the motion of fast moving object in detail. This paper describes the basic concepts of the high speed film camera and high speed digital camera and the history and future technical trends in high speed camera industry. In addition, application field of high speed camera in Korea as well as other countries and future plan to use high speed camera in Naro Space Center has been descried.

  • PDF

Development of Condition Monitoring System for Reduction Unit of High-speed Rail (고속열차용 감속기 모니터링 시스템 개발)

  • Lee, Dong-Hyong;Kwon, Seok Jin;Park, Byoung-Su;Cho, Duk-Young;Kim, Jin-Woo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.7
    • /
    • pp.667-672
    • /
    • 2013
  • This paper presents the development of a condition monitoring system that monitors the operating conditions of a reduction unit, such as the bearing temperature, gearbox vibration, and gear oil deterioration, and notifies the operator of potential problems or abnormal conditions. A series of field tests on high-speed rail and conventional lines was performed to identify the characteristics of temperature rise and vibration levels on the reduction unit during operation. The monitoring system was designed based on the proper sensor selection, measurement method, and signal analysis to optimize the interface with the operating system of high-speed trains. Application of this monitoring system to high-speed trains will play an important role in their proper maintenance and safe operation.

Performance Analysis for Regenerative Energy Storage System in Kyoung-bu High Speed Railway (경부고속철도 회생 에너지 저장시스템 성능 분석)

  • Jang, Min-Ju;Jeon, Yong-Joo;Lho, Young Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.9
    • /
    • pp.1391-1397
    • /
    • 2015
  • Recently, various researches are conducted in the application of regenerative energy produced during the operation of an electric locomotive. Regenerative energy is produced by a generator in the brake procedure. The generator is operated by kinetic energy of an electric railroad using an electric motor. The process of producing regenerative energy varies with the current type of a railroad and its running condition. The quality of electric power can be improved and electric energy can be utilized effectively, especially in the use of an energy storage system (ESS). Thus, it is necessary to apply ESS into AC section and high speed railway. This study analyses the composition of the regenerative ESS equipment installed in Yong-Jeong sectioning post, operational principle, charge and discharge algorithm and energy efficiency. The analysis shows that CO2 emissions can be reduced about 0.5 ton per a day. In addition, ESS helps saving the energy and the compensation of the voltage drop caused by the operation of high speed train when it is installed at the end of the feeder section. The number of high speed train will be increased continuously related to the electrification rate. Therefore, applying the ESS to high speed railway is expected to solve the instability of the feeder voltage and the equipment capacity problem caused by the high speed trains.