• Title, Summary, Keyword: Synchronous

Search Result 3,908, Processing Time 0.04 seconds

A Study on Excitation System for Synchronous Generator using Current Mode Controlled PWM Converter (전류제어형 PWM컨버터를 이용한 동기발전기용 여자시스템에 관한연구)

  • 장수진;류동균;서민성;김준호;원충연;배기훈
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • /
    • pp.151-156
    • /
    • 2002
  • The output voltage of Synchronous Generator is regulated constantly by field current control in excitation system. A synchronous generator is equipped with an automatic voltage regulator(AVR), which is responsible for keeping the constant output voltage under normal operating conditions about various levels. High frequency PWM converter (Current Mode Control Buck converter) type excitation system for synchronous generator is able to sustain output voltage level properly when the fault condition happened. This paper deals with the design and evaluation of the excitation system controller for a synchronous generator to improve the steady state and transient stability. The simulation and experimental results show that the proposed excitation system is improve the respons time by the AVR(automatic voltage regulator) of 50kW synchronous generator that is applied the current mode control excitation system.

  • PDF

A Study on the Position-Synchronous Control of Coupling Structure by H Approach (H제어기법에 의한 커플링구조의 위치동기제어에 관한 연구)

  • Byun, Jung-Hoan
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.10
    • /
    • pp.2052-2059
    • /
    • 2002
  • In this study, a synchronous controller algorithm being applicable to two-axis position synchronzation is developed. Based on coupling structure, the synchronous control system is composed of speed and synchronous controllers. The speed controller is designed to follow a speed reference. In addition, the synchronous controller is designed from the viewpoint of accurate synchronization and robust stability in H$\infty$ synthesis. Finally, the effectiveness of the presented controller is demonstrated through extensive experiments.

Research on the Power Sharing Control and Stability of VSGs

  • Xie, Dong;Zang, Da-Jin;Gao, Peng;Wang, Jun-Jia
    • Journal of Power Electronics
    • /
    • v.17 no.2
    • /
    • pp.542-550
    • /
    • 2017
  • Aiming at the deficiencies of power sharing control performances when a traditional droop control is adopted for microgrid inverters, this paper proposes a microgrid inverter power sharing control strategy based on a virtual synchronous generator. This control method simulates the electromechanical transient characteristics of a synchronous generator in a power system by an ontology algorithm and the control laws of a synchronous generator by control over the speed governor and excitation regulator. As a result, that the microgrid system is able to effectively retain the stability of the voltage and frequency, and the power sharing precision of the microgrid inverter is improved. Based on an analysis of stability of a microgrid system controlled by a virtual synchronous generator, design thoughts are provided for further improvement of the power sharing precision of inverters. The simulation results shows that when the virtual synchronous generator based control strategy was adopted, the power sharing performances of microgrid inverters are improved more obviously than those using the droop control strategy.

Design of Brushless Synchronous Motor with an Inverter Integrated Rotor (회전자 인버터 내장형 Brushless 동기 전동기 설계)

  • Do, Sang-Hwa;Lee, Byung-Hwa;Chae, Seung-Hee;Hong, Jung-Pyo;Jung, Eun-Soo;Sul, Seung-Ki
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.939-940
    • /
    • 2011
  • This paper deals with the design of a brushless synchronous motor with an inverter integrated rotor instead of a brush and a slip ring. It is designed for 80kW output power and compared with an induction motor and a permanent magnet synchronous motor of the same specifications. Brushless synchronous motor, induction motor and permanent magnet synchronous motor have the same amount of magnet flux density at an air gap. As a result, the brushless synchronous motor can be reduced volume of motor and power losses comparing to the induction motor.

  • PDF

Sub-Synchronous Range of Operation for a Wind Driven Double-Fed Induction Generator

  • Saleh, Mahmoud Abdel Halim;Eskander, Mona Naguib
    • Journal of Power Electronics
    • /
    • v.10 no.1
    • /
    • pp.72-78
    • /
    • 2010
  • In this paper the operation of a double-fed wound-rotor induction machine, coupled to a wind turbine, as a generator at sub-synchronous speeds is investigated. A novel approach is used in the analysis, namely, the rotor power flow approach. The conditions necessary for operating the machine as a double-fed induction generator (DFIG) are deduced. Formulae describing the factors affecting the range of sub-synchronous speeds within which generation occurs are deduced. The variations in the magnitude and phase angle of the voltage injected to the rotor circuit as the speed of the machine changes to achieve generation at the widest possible sub-synchronous speed range is presented. Also, the effect of the rotor parameters on the generation range is presented. The analysis proved that the generation range could increase from sub-synchronous to super-synchronous speeds, which increases the amount of energy captured by the wind energy conversion system (WECS) as result of utilizing the power available in the wind at low wind speeds.

Clamp mode forward multi-resonant conveter with synchronous rectifier (동기 정류기를 이용한 클램프 모드 포워드 다중 공진형 컨버터)

  • 안강순;김희준
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.34S no.2
    • /
    • pp.112-120
    • /
    • 1997
  • The clamp mode (CM) forward zero voltage switching multi resonant converter (ZVS-MPC) with self-driven synchronous rectifier is studied. The loss at the synchronous rectification stage of the converter is analyzed using MOSFET piecewise linear model and is compared with the loss at the conventional schottky diode rectification stage of th econverter. From the results of the analysis, it is known that the use fo MOSFETs as a synchronous rectifier reduces the loss at the rectification stage overthe whole load range comparing the use of schottky diodes as a conventional rectifier in the converter. In order to verify the validit of the analysis, we have built a 33W(3.3V/10A) CM forward ZVS-MRC with self-driven synchronous rectifier, in which switching frequency is 1MHz, and tested. FRom the experimental results, it is known that the synchronous rectification achieved about 1W improvement in the loss at the rectification stage and about 3% in the efficiency at the converter as compared with the conventional schottky diode rectification.

  • PDF

Direct Torque Control of a Synchronous Reluctance Motor Using the Finite Element Method

  • Lee Sang-Don
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
    • /
    • v.5B no.2
    • /
    • pp.173-180
    • /
    • 2005
  • The construction of a Synchronous Reluctance Motor (SynRM) is simple and also highly economical because a stator from the existing AC motor can be used. Since the synchronous inductance in the Synchronous Reluctance Motor is an element that is proportional to torque, its exact value must be experimentally or analytically found for accurate control and performance development of the motor. In this paper, direct torque control (DTC) simulation is carried out to maximize the torque of the Synchronous Reluctance Motor and the fast response characteristics with the inductance value by the Finite Element Method (FEM). The response characteristics are compared through the proposed direct torque control and torque response characteristics that are based on the existing PI Control in order to confirm the fast response features. To test the performance of the direct torque controller, the torque response is analyzed with variable speed and load condition.

Real Time Simulator for a Permanent Magnet Synchronous Motor with Power Converter (전력변환기를 이용한 영구자석 동기전동기용 실시간 시뮬레이터)

  • Oh, Hyun-Cheal;Kim, Hag-Wone;Cho, Kwan-Yuhl
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.27 no.12
    • /
    • pp.114-124
    • /
    • 2013
  • Recently, the real time simulator to develop the inverter drive board and motor control algorithm for high power induction motor and PM synchronous motor is required. In this paper, the real time simulator based on the voltage control for a PM synchronous motor is proposed. The resistor, inductor, and the induced voltage for the modeling of a PM synchronous motor is implemented by the power converter including the LCL filter and the PWM rectifier. The induced voltage of a PM synchronous motor is simulated by the capacitor voltage of the LCL filter, which is controlled by PI voltage controller and the deadbeat current controller. The operation and the simulated characteristics of the proposed real time simulator for a PM synchronous motor is verified by the simulation.

A Driving Scheme Using a Single Control Signal for a ZVT Voltage Driven Synchronous Buck Converter

  • Asghari, Amin;Farzanehfard, Hosein
    • Journal of Power Electronics
    • /
    • v.14 no.2
    • /
    • pp.217-225
    • /
    • 2014
  • This paper deals with the optimization of the driving techniques for the ZVT synchronous buck converter proposed in [1]. Two new gate drive circuits are proposed to allow this converter to operate by only one control signal as a 12V voltage regulator module (VRM). Voltage-driven method is applied for the synchronous rectifier. In addition, the control signal drives the main and auxiliary switches by one driving circuit. Both of the circuits are supplied by the input voltage. As a result, no supply voltage is required. This approach decreases both the complexity and cost in converter hardware implementation and is suitable for practical applications. In addition, the proposed SR driving scheme can also be used for many high frequency resonant converters and some high frequency discontinuous current mode PWM circuits. The ZVT synchronous buck converter with new gate drive circuits is analyzed and the presented experimental results confirm the theoretical analysis.

The Application of Classical Direct Torque and Flux Control (DTFC) for Line-Start Permanent Magnet Synchronous and its Comparison with Permanent Magnet Synchronous Motor

  • Soreshjani, Mohsen Hosseinzadeh;Heidari, Reza;Ghafari, Ahmad
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.6
    • /
    • pp.1954-1959
    • /
    • 2014
  • This paper attempts to design and present a comparison of classical Direct Torque Flux Control (DTFC) for Line-Start Permanent Magnet Synchronous Motor (LSPMSM) and its equal Permanent Magnet Synchronous Motor (PMSM). In order to present an in-depth analysis, both motors for DTFC Voltage Source Inverter (VSI)-fed in the same situations of different conditions are simulated and tested. The advantages of the proposed method for LSPMSM over the PMSM are discussed and analyzed.