• Title/Summary/Keyword: source-synchronous

Search Result 238, Processing Time 0.028 seconds

A Study on the Series Active Power Filter for Harmonic Reduction and Unbalanced Source Voltage Compensation (전류 고조파와 불평형 전원 전압 보상을 위한 직렬형 능동전력필터에 관한 연구)

  • Oh, Jae-Hoon;Han, Yoon-Seok;Kim, Young-Seok;Won, Chung-Yuen;Choi, Se-Wan
    • Proceedings of the KIEE Conference
    • /
    • 2001.04a
    • /
    • pp.191-194
    • /
    • 2001
  • In this paper, we propose a series active power filter control method to compensate current harmonics and unbalanced source voltage. The system is composed of series active power filter and shunt passive filer that are tuned 5th and 7th harmonics. In this conventional system, series active power filter complements drawbacks of the shunt passive filter, namely improves harmonic compensation characteristics, and compensates unbalanced source voltage. In the proposed algorithm, compensation voltage for harmonic reduction is calculated by performance function, and compensation voltage for unbalanced source voltage is calculated in based on a synchronous reference frame. So, ultimate compensation voltage is sum of those two compensation voltages. By computer simulation, we verify the excellency of proposed method.

  • PDF

A Study of Series Active Power Filter Compensating Unbalanced Source Voltage in 3phase-3wire system (불평형 전원전압을 보상하는 3상3선식 직렬형 능동전력필터에 관한 연구)

  • Oh, Jae-Hoon;Kim, Young-Seok;Han, Yoon-Seok;Won, Chung-Yuen;Chol, Se-Wan
    • Proceedings of the KIPE Conference
    • /
    • 2001.07a
    • /
    • pp.319-322
    • /
    • 2001
  • In this paper, a 3phase-3wire series active power filter compensating current harmonics and unbalanced source voltages is presented. The system is composed of series active power filter and shunt passive filters that are tuned 5th and 7th harmonics. In this system, series active power filter improves harmonic compensation characteristics of the shunt passive filters and compensates the unbalanced source voltages. In the proposed algorithm, compensation voltage for harmonic reduction is calculated by a performance function, and compensation voltage for the unbalanced source voltage is calculated in based on the synchronous reference frame. Some results obtained from the experimental model using the proposed method are presented to demonstrate and confirm its validity.

  • PDF

Microprocessor Based Permanent Magnet Synchronous Motor Drive (마이크로 프로세서에 의한 영구자석동기 전동기의 구동)

  • Yoon, Byung-Do
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.35 no.12
    • /
    • pp.541-554
    • /
    • 1986
  • This paper presents the results of driving performance analysis of permanent magnet synchronous motor using a microprocessor based control system. The system consists of three phase power transistor inverters, three phase controlled rectifier, three central processing units, and sensors. The three CPUs are, respectively, used to generate PWM control signals for the inverter generating three phase sine wave, to generate the gate control signals for firing the converter, and to supervise other two CPUs. The supervisor is used to compute PI control algtorithm to three phase reference sine wave for the inverter. It is also used to maintain a constant voltage frequency ratio for the converter operating as a constant torque controller. The inverter CPU retrieves precomputed PWM patterns from look up tables because of computation speed limitations found in almost available microprocessors. The converter CPU also retrieves precomputed gate control patterns from another look-up tables. For protecting the control ststem from any damage by extraordinary over currents, the supervisor receives the data from current sensor, CT, and break down the CB to isolate the circuits from source. A resolver has a good performance characteristics of overall speed range, especially on low speed range. Therefor the speed control accuracy is impoved. The microprocessor based PM synchronous motor control system, thus, has many advantages such as constant torque characteristics, improvement of wave, limitation on extraordinary over currents, improvement of speed control accuracy, and fast response speed control using multi-CPU and look-up tables.

  • PDF

A Study on the reduction of cogging force of stationary discontinuous armature Permanent Magnet Linear Synchronous Motor by change in Auxiliary pole (보조극 변화에 따른 전기자 분산배치 영구자석형 리니어 동기 모터의 코깅력 저감에 관한 연구)

  • Lee, Kyu-Myung;Kim, Yong-Jae
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.5 no.6
    • /
    • pp.613-619
    • /
    • 2010
  • The stationary discontinuous armatures that are used in permanent magnet linear synchronous motors (PM-LSMs) have been proposed as a driving source for transportation systems. However, the stationary discontinuous armature PM-LSM contains the outlet edges which always exist as a result of the discontinuous arrangement of the armature. For this reason, the outlet edge cogging force generated between the armature's core and the mover's permanent magnet. This paper contemplated the outlet cogging for ceaccording to 2-D numerical analysis by FEM. We installed the auxiliary pole for in order to minimize the outlet cogging force.

Torque Ripple Reduction of an Interior PM Synchronous Motor by Compensating Harmonic Currents Based on Flux Linkage Harmonics

  • Nam, Myung Joon;Kim, Jong Hyun;Cho, Kwan-Yuhl;Kim, Hag-Wone;Cho, Younghoon
    • Journal of Power Electronics
    • /
    • v.17 no.5
    • /
    • pp.1223-1230
    • /
    • 2017
  • The back emf harmonics of a permanent magnet (PM) synchronous motor is a major source of torque ripple. For torque control applications including column fitted MDPS (motor driven power steering) systems, it is essential to reduce the mechanical vibrations due to torque ripples at low speeds. In this paper, a torque ripple reduction algorithm for interior PM synchronous motors is proposed. The harmonic currents that cancel the $6^{th}$ order torque harmonic are added to the nominal dq currents for MTPA (maximum torque per ampere) operation. The compensated harmonic currents are derived from flux linkage harmonics based on a FFT analysis of the back emf harmonics. Simulation and experimental results verify that the $6^{th}$ order torque harmonic and THD of the torque ripple are reduced by compensating the dq harmonic currents.

Cogging Force Verification of the Back-yoke Length of a Moving-coil-type Slotless Linear Synchronous Motor

  • Kim, Yong-Jae;Jung, Sang-Yong
    • Journal of Magnetics
    • /
    • v.14 no.1
    • /
    • pp.47-51
    • /
    • 2009
  • The coreless linear synchronous motor (coreless LSM) has been widely used as a driving source of semiconductor production processes for machine speeding up, positioning accuracy and simple maintenance. However, this coreless LSM suffers the disadvantage of decreased thrust force created by the leakage of magnetic flux. With the goal of increasing the generated thrust force and decreasing the cogging force, the slot of the core part was removed and a moving-coil-type slotless LSM (moving-coil-type slotless LSM) is proposed in this paper. Although this moving-coil-type slotless LSM with a back-yoke at the primary side demonstrated an increase in the generated thrust force, it remained capable of generating the cogging force when the primary side was moved due to the position between the permanent magnet and the back-yoke. Therefore, we attempted to decrease the cogging force of the moving-coil-type slotless LSM. We found that the back-yoke length at the primary side needs to be made $0.5{\tau}$ longer than the integral multiple of the magnetic pole pitch in order to decrease the cogging force created by the moving-coil-type slotless LSM.

Experimental Verification of Compressor Blade Aeromechanics (압축기 블레이드 Aeromechanics의 시험적 검증)

  • Choi, Yun Hyuk;Park, Hee Yong;Kim, Jee Soo;Shin, Dong Ick;Choi, Jae Ho;Kim, Yeong Ryeon
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2017.05a
    • /
    • pp.240-244
    • /
    • 2017
  • Experimental verification in the rig test stage for component development is a vital link between the aeromechanical design and structural integrity validation process. Based on this premise, Non-Intrusive Stress Measuring System was adopted on the axial compressor test rig to measure the static and dynamic tip deflection of all blades by using tip-timing sensors. Through analyzing vibration characteristics, we evaluated the vibratory stresses seen on the blades fatigue critical location; detected synchronous resonances which are the source of High Cycle Fatigue (HCF) in blades; presented non-synchronous vibration response by aerodynamic excitation and individual blade mis-tuning patterns.

  • PDF

VSI FACTS Modeling Using Newton-Type Current Injection Method for Studying Power System Dynamics (전력시스템 동특성 해석을 위한 전압원 FACTS 기기의 Newton 전류 주입형 모델링에 관한 연구)

  • Park, Jung-Soo;Son, Kwang-M.;Jang, Gil-Soo
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.55 no.7
    • /
    • pp.281-289
    • /
    • 2006
  • Advanced controllers among Flexible AC Transmission System(FACTS) devices employ self-commutated switching converters, VSI (Voltage Sourced Inverters), as the synchronous voltage source. Such controllers are SSSC (Static Synchronous Series Compensator), STATCOM (Static Synchronous Compensator) and UPFC (Unified Power Flow Controller). UPFC is series-shunt combined controller. Its series and shunt inverters can be modeled as SSSC and STATCOM but the dependant relation between the inverters is very complex. For that reason, the complexity makes it difficult to develop the UPFC model by simply combining the SSSC and STATOM models when we apply the model for conventional power system dynamic simulation algorithm. Therefore, we need each relevant models of VSI type FACTS devices for power system analysis. This paper proposes a modeling approach which can be applied to modeling of VSI type FACTS devices. The proposed method using Newton-type current injection method can be used to make UPFC, SSSC, and STATCOM models. The proposed models are used for 2-area test system simulation, and the results verify their effectiveness.

Individual DC Voltage Balancing Method at Zero Current Mode for Cascaded H-bridge Based Static Synchronous Compensator

  • Yang, Zezhou;Sun, Jianjun;Li, Shangsheng;Liao, Zhiqiang;Zha, Xiaoming
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.1
    • /
    • pp.240-249
    • /
    • 2018
  • Individual DC voltage balance problem is an inherent issue for cascaded H-bridge (CHB) based converter. When the CHB-based static synchronous compensator (STATCOM) is operating at zero current mode, the software-based individual DC voltage balancing control techniques may not work because of the infinitesimal output current. However, the different power losses of each cell would lead to the individual DC voltages unbalance. The uneven power losses on the local supplied cell-controllers (including the control circuit and drive circuit) would especially cause the divergence of individual DC voltages, due to their characteristic as constant power loads. To solve this problem, this paper proposes an adaptive voltage balancing module which is designed in the cell-controller board with small size and low cost circuits. It is controlled to make the power loss of the cell a constant resistance load, thus the DC voltages are balanced in zero current mode. Field test in a 10kV STATCOM confirms the performance of the proposed method.

Flux Weakening Control for Surface Mounted Permanent Magnet Synchronous Machine Driven by Dual Inverter (이중 인버터를 이용한 표면 부착형 영구자석 동기전동기의 약자속 제어)

  • Kim, Youngnam;Lee, Yongjae;Ha, Jung-Ik
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.18 no.5
    • /
    • pp.437-442
    • /
    • 2013
  • For open-end permanent magnet synchronous machine(PMSM) with dual inverter system, where one inverter is connected to the source and the other is flying, the dc link voltage of the flying inverter can be boosted through the machine. For this reason, when compared with single inverter drive system, higher voltage can be applied to PMSM, and higher torque can be generated in the flux weakening region. In this case, however, active and reactive powers are separately supplied by each inverter to maintain the dc link voltage of flying inverter. Therefore, the required flux weakening control is different from the conventional method for a single inverter drive system. This paper proposes the novel flux weakening control method which maximizes the active voltage component in a dual inverter PMSM drive system. The proposed method was demonstrated and verified through experimental results.