• Title/Summary/Keyword: Mode Switching Control

Search Result 9, Processing Time 0.183 seconds

A New Mode Switching Control for Fast Settling and High Precision Positioning (고속 세틀링과 고정밀 위치 제어를 위한 모드 변경 제어 기법)

  • Kim, Jung-Jae;Choi, Young-Man;Kim, Ki-Hyun;Gweon, Dae-Gab;Hong, Dong-Pyo
    • Journal of the Semiconductor & Display Technology
    • /
    • v.5 no.4
    • /
    • pp.1-4
    • /
    • 2006
  • Recently, with rapid development of digital media like semiconductor and large flat panel display, the manufacturing equipment is required to have high precision over large travel range. Moreover it should have high product throughput. To achieve high product throughput, a controller should perform fast point-to-point motion and high precision positioning after settling in spite of external disturbances or residual vibrations. We proposed a new mode switching control algorithm with an application to dual stage for long range and high precision positioning. The proposed algorithm uses a proximate time-optimal servomechanism for the fast settling and a time-delay controller for the high precision positioning. Experimental results show that the proposed method enables smooth mode switching and improves the settling time and the precision accuracy after settling by over than 33% and 45%, respectively.

  • PDF

Mode Switching Control Design for Gun/Turret Driving System (포/포탑 구동장치의 모드 스위칭 제어기 설계)

  • Baek, Seoung-Mun;Kim, Ji-Young;Yim, Jong-Bin;Lyou, Joon
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.33-37
    • /
    • 2004
  • To meet an increasing demand for high performance in gun dynamic plant, both a precise and a fast response positioning are strongly required for the gun servomechanism control. A mode switching control(MSC) system, which includes a fine stabilizing controller, fast positioning one and a switching function, is widely used to meet this requirement. Stabilization is performed through PID controller, while proximate time optimal servo(PTOS) is used for target designation. Because gun dynamic have large damping comparing to acceleration, PTOS algorithm with damping is newly derived. This paper adopts the initial value compensation method that improve the transient response after switching. Some simulation results are given to show the effectiveness of our scheme.

  • PDF

Driving of Switched Reluctance Motor to Reduce Torque Ripple (맥동 토오크 저감을 위한 스위치드 리럭턴스 전동기 구동에 관한 연구)

  • 오인석;성세진
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.2 no.2
    • /
    • pp.49-56
    • /
    • 1997
  • Switched Reluctance Motors(SRMs) have a considerable inherent torque ripple due to the driving characteristics of pulse current waveform and the nonlinear variation inductance profile. This paper describes a current shape characteristics to effect a torque ripple reduction, and one pulse mode switching control method is proposed to minimize torque ripple of a switched reluctance motor regardless of speed and load condition by regulating tow parameters, such as, advance angle and exciting voltage. The experiments are performed to verify the capability of proposed switching method on 6/4 salient type SRM.

  • PDF

Design of a Mode Switching Controller for Gun Servo System (포 구동시스템에 대한 모드 스위칭 제어기 설계)

  • Yim Jong-Bin;Baek Seoung-Mun;Lyou Joon
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.12 no.5
    • /
    • pp.425-430
    • /
    • 2006
  • To meet an increasing demand for high performance in gun dynamic plant, both a precise and a fast response positioning are strongly required for the gun servo system. A mode switching control(MSC) scheme, which includes a fine stabilizing controller, fast positioning one and a switching function, is widely used to meet this requirement. Stabilization is performed through PID controller, while a time optimal control method is used for target designation. In this paper, a modified PTOS(Proximate Time Optimal Servomechanism) algorithm is derived so as to accommodate the damping term in the gun plant model. Also, applying a mode switching strategy, the bumpless transfer is made possible when the controller switches from PTOS to PID. To show the effectiveness of the overall control system, simulation results are given including the gun dynamics.

Mode Switching Smooth Control of Transient Process of Grid-Connected 400 Hz Solid-State Power Supply System

  • Zhu, Jun-Jie;Nie, Zi-Ling;Zhang, Yin-Feng;Han, Yi
    • Journal of Power Electronics
    • /
    • v.16 no.6
    • /
    • pp.2327-2337
    • /
    • 2016
  • The mode-switching control of transient process is important to grid-connected 400 Hz solid-state power supply systems. Therefore, this paper analyzes the principle of on-grid and islanding operation of the system with or without local loads in the grid-connected process and provides a theoretical study of the effect of different switching sequences on the mode-switching transient process. The conclusion is that the mode switch (MS) must be turned on before the solid-state switch (STS) in the on-grid process and that STS must be turned off before the MS in the off-grid process. A strategy of mode-switching smooth control for transient process of the system is proposed, including its concrete steps. The strategy utilizes the average distribution of peak currents and the smooth adjustment of peak currents and phases to achieve a no-shock grid connection. The simulation and experimental results show that the theoretical analysis is correct and that the method is effective.

A CMOS 5.4/3.24-Gbps Dual-Rate CDR with Enhanced Quarter-Rate Linear Phase Detector

  • Yoo, Jae-Wook;Kim, Tae-Ho;Kim, Dong-Kyun;Kang, Jin-Ku
    • ETRI Journal
    • /
    • v.33 no.5
    • /
    • pp.752-758
    • /
    • 2011
  • This paper presents a clock and data recovery circuit that supports dual data rates of 5.4 Gbps and 3.24 Gbps for DisplayPort v1.2 sink device. A quarter-rate linear phase detector (PD) is used in order to mitigate high speed circuit design effort. The proposed linear PD results in better jitter performance by increasing up and down pulse widths of the PD and removes dead-zone problem of charge pump circuit. A voltage-controlled oscillator is designed with a 'Mode' switching control for frequency selection. The measured RMS jitter of recovered clock signal is 2.92 ps, and the peak-to-peak jitter is 24.89 ps under $2^{31}-1$ bit-long pseudo-random bit sequence at the bitrate of 5.4 Gbps. The chip area is 1.0 mm${\times}$1.3 mm, and the power consumption is 117 mW from a 1.8 V supply using 0.18 ${\mu}m$ CMOS process.

A Study on the Operating Control of a Heat Pump System with Screw Compressors (스크류 열펌프 시스템의 운전제어 방안에 관한 연구)

  • Park, Jun-Tark;Lee, Young-Soo;Kim, Jiyoung;Chae, Kyu-Jung;Yang, Hee-Jung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.25 no.3
    • /
    • pp.168-172
    • /
    • 2013
  • A preliminary performance test of a 30RT 2-stage screw heat pump was carried out in order to develop a high performance large-scale unutilized energy source heat pump system, which will be used for district heating and cooling. In this study, two issues of the system operating control were investigated. The first issue is the mode switching control from 1-stage to 2-stage. A stable 2-stage heating operation is guaranteed, only if the load-side water inlet temperature is over a certain value, where the 1-stage heating operation should be done first from a cold start. The second issue is oil level control. An oil shortage problem in the low stage compressor, which depends on the degree of suction superheat, was solved by a proper oil level control scheme.

An Experimental Study on Mode Switching from Air-firing to Oxy-firing in Pilot-scale Combustion Systems (미분탄 순산소 연소 운전 모드 전환 과정에 대한 Pilot 규모 설비에서의 실험적 연구)

  • Choi, Chong-Gun;Na, Ik-Hwan;Lee, Jae-Wook;Chae, Tae-Young;Yang, Won;Kim, Young-Ju;Kim, Jong-An;Seo, Sang-Il
    • Journal of the Korean Society of Combustion
    • /
    • v.16 no.3
    • /
    • pp.12-20
    • /
    • 2011
  • Oxy-coal combustion for $CO_2$ capture in coal power plants entails a mode switching from air-firing to oxyfiring. In this study, procedure of the mode switching was investigated and discussed through experiments in pilot scale facilities: (1) a 0.3 $MW_{th}$ furnace with a vertical single burner and a FGR(Flue Gas Recirculation) system (2) a 1 $MW_{th}$ furnace with horizontal 4 burners and a FGR system. Principle of the mode switching was established and performed with control of FD fan, FGR fan, ID fan and oxygen flow rates. We have found that equivalence ratio in the oxy-firing mode should be increased more than that in the air-firing to achieve stable mode switching. Control of FD, ID and FGR fans should be performed carefully in the mode switching, in the sense of complete combustion and flame attachment. Moisture contents in the ash and the flue gas recycled to the primary oxidizer stream should be removed to prevent condensation, corrosion and duct clogging.

Improvement of the Transient Response by Partially Compensating Initial Values of Digital Controllers (디지털 제어기의 부분적 초기값 보상을 통한 천이 응답 특성 향상)

  • Doh, Tae-Yong;Ryoo, Jung Rae
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.19 no.4
    • /
    • pp.285-289
    • /
    • 2013
  • In switching from the track-seeking or track-jumping control mode to track-following control mode in hard disk drives or optical disk drives, initial values of the feedback controller are tuned to improve the transient response. In general, all the initial values of the controller have been compensated for this purpose. In this paper, by partially compensating initial values of digital controllers, we achieve a good performance of the transient response. In the proposed method for IVC (Intial Value Compensation), LMIs (Linear Matrix Inequalities) are used, which includes conditions for improving the performance of the transient response such as reducing a tracking error and control efforts. We obtain optimal initial values of the controller by solving an optimization problem with constraints represented by only one LMI. Although initial values of the controller are partially compensated, we can show that not only a sufficient performance of the transient response is obtained but also control efforts are diminished. The feasibility of the method is verified by simulation studies.