• Title, Summary, Keyword: Position Control

Search Result 6,250, Processing Time 0.052 seconds

A Simulation Study of Position Control Performance of a Shape Memory Alloy-Actuated Flow Control Valve (형상기업합금을 이용한 유량제어밸브의 위치제어 적용 시뮬레이션)

  • Choi, Su-Hyun;Lee, Han-Suk;Kuk, Kum-Hoan
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.16 no.8
    • /
    • pp.79-87
    • /
    • 1999
  • In this study, a new type of flow control valve which is SMA actuated flow control valve is presented. The flow control valve is actuated by a small motion of shape memory alloy. The performance of this valve as a position control component is analyzed by computer simulation. A variable structure control technique is applied for the position control by the flow control valve. The position control performance of the valve is evaluated on the step responses of a PID control by a electrohydraulic servo valve. For the simulation study, first, the mathematical model of a hydraulic system, which is consisted of the flow control valve and a hydraulic cylinder, is formulated. This mathematical model and the designed variable structure control algorithm are then combined by the MATLAB software. The same sequence of work is carried out for the PID position control system with a electrohydraulic servo valve. The simulation results show the validity of the new type of flow control valve as a variable position control component.

  • PDF

Anti-swing and position control of crane using fuzzy controller (퍼지제어기를 이용한 크레인의 진동억제 및 위치제어)

  • Jeong, Seung-Hyun;Park, Jung-Il
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.3 no.5
    • /
    • pp.435-442
    • /
    • 1997
  • The roof crane system is used for transporting a variable load to a target position. The goal of crane control system is transporting the load to a goal position as quick as possible without rope oscillation. The crane is generally operated by an expert operator, but recently an automatic control system with high speed and rapid tansportation is required. In this paper, we developed a simple fuzzy controller which has been introduced expert's knowledge base for anti-swing and rapid tranportation to goal position. In particular, we proposed the synthesis reasoning method which synthesizes on the basis of expert knowledge of the angle control input and position control input which are inferenced parallel and simultaneously. And we confirmed that the performance of the developed controller is effective as a result of applying it to crane simulator and also verified whether the proposed synthesis rules have been applied correctly using clustering algorithm from the measured data.

  • PDF

Mathematical Analysis and Simulation Based Survey on Initial Pole Position Estimation of Surface Permanent Magnet Synchronous Motor

  • Kim, Tae-Woong;Wheeler, Patrick;Choi, Jae-Ho
    • Journal of Power Electronics
    • /
    • v.9 no.3
    • /
    • pp.499-506
    • /
    • 2009
  • In this paper, the initial pole-position estimation of a surface (non-salient) permanent magnet synchronous motor is mathematically analyzed and surveyed on the basis of simulation analysis, and developed for accurate servo motor drive. This algorithm is well carried out under the full closed-loop position control without any pole sensors and is completely insensitive to any motor parameters. This estimation is based on the principle that the initial pole-position is simply calculated by the reverse trigonometric function using the two feedback currents in the full closed-loop position control. The proposed algorithm consists of the predefined reference position profile, the information of feedback currents, speed, and relative position, and the reverse trigonometric function for the initial-pole position estimation. Comparing with the existing researches, the mathematical analysis is introduced to get a more accurate initial pole-position of the surface permanent magnet motor under the closed-loop position control. It is found that the proposed algorithm can be easily applied in servo drive applications because it satisfies the following user's specifications; accuracy and moving distance.

Sensorless Position Control of DC Motor for the Auxiliary Scaffolding (차량용 보조발판의 센서리스 직류전동기 위치 제어)

  • Lee, Dong-Hee
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.24 no.6
    • /
    • pp.389-395
    • /
    • 2019
  • This paper presents the sensorless position control of an auxiliary scaffolding step system for vehicles using DC motors. The designed auxiliary scaffolding step has a mechanical protector at the stop position. At this position, the scaffolding is forcibly stopped by the mechanical protector, and the motor current is dramatically increased to the stall current of the DC motor, thereby increasing the electrical damage. In this study, the estimated back EMF- and current model-based observers are proposed to estimate the motor speed and stop position. A simple V/F acceleration voltage pattern is used to operate the auxiliary scaffolding system. The estimated moving position is adopted to determine the stop position of the DC motor with the load current state. The operating current of the DC motor can be reduced by the estimated moving position and V/F acceleration pattern. At the stop position, the proposed sensorless position controller can smoothly stop the DC motor with the estimated moving position and reduced load current without any mechanical and electrical stress from the stall current from the mechanical protector. The proposed control scheme is verified by the comparison of simulations and experiments.

A Study on Minimum Time Position Control of DC Servo-Motor (DC Servo Motor의 최단시간 위치 제어)

  • 양주호
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.28 no.1
    • /
    • pp.39-44
    • /
    • 1992
  • Analog PID controllers have been designed to make good use of position control in industries. Recently, the importance of digital position control is emphasized for the requirements of controller which are not only to control the objects but to include various aspects such as easiness of design and implementation, simple exchange of control program and convenient communications of data between various controllers and a host computer. This study proposes a combined control method which is mixed the vaiable structure control (VSC) with the PI control for minimum time position control of DC servo motor by microcomputer. The results of test by this method show offset-free and minimum time optimal position control which is not affected by the disturbance and the system parameter variations. The validity of the proposed method comparing with the conventional PID control is proved by the response experiments.

  • PDF

Position Control of an Electro Hydraulic Actuator Using Adaptive Control Method (적응제어 기법을 이용한 전기-유압 액츄에이터의 위치제어)

  • Cho, S.H.
    • Transactions of The Korea Fluid Power Systems Society
    • /
    • v.7 no.3
    • /
    • pp.1-6
    • /
    • 2010
  • This paper deals with the issue of simple adaptive position control for a pump-controlled cylinder system. A fixed displacement pump is utilized instead of servo valve and its speed is controlled by AC motor. The whole control system is composed of a pair of interconnected subsystems, that is, a feedback control system and a feedforward control system. From experiments it is shown that position control using simple adaptive control can accomplish significant reduction in position tracking error comparing to a conventional PID control.

  • PDF

Position and swing angle control for loads of overhead cranes (천정크레인 부하의 위치 및 흔들림 제어)

  • Lee, Ho-Hoon;Cho, Sung-Kun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.21 no.2
    • /
    • pp.297-304
    • /
    • 1997
  • This paper presents a systematic design method of an anti-swing control law for overhead cranes. A velocity servo system for the trolley of a crane is designed based on the dynamics of the trolley and its load. The velocity servo system compensates for the effects of load swing on the trolley dynamics so that the velocity servo is independent of load swing. The velocity servo system is used for the design of a position servo system for the trolley via the loop shaping method. The position servo system and the swing dynamics of the load are then used to design an angle control system for load swing based on the root locus method. The combined position servo and the angle control systems constitute the overall control system. In the presence of low frequency disturbances, the proposed control law guarantees accurate position control for the trolley and fast damping for load swing. Furthermore, the performance of the proposed control law is independent of the mass of the load. Experimental results on a prototype crane show the effectiveness of the proposed anti-swing control law.

Fuzzy Control Algorithm Eliminating Steady-state Position Errors of Robotic Manipulators (로봇 머니퓰레이터의 정상상태 위치오차를 제거할 수 있는 퍼지제어 알고리듬)

  • Kang, Chul-Goo;Kwak, Hee-Sung
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.21 no.3
    • /
    • pp.361-368
    • /
    • 1997
  • In order to eliminate position errors existing at the steady state in the motion control of robotic manipulators, a new fuzzy control algorithm is propeosed using three variables, position error, velocity error and integral of position errors as input variables of the fuzzy controller. Although the number of input variables of the fuzzy controller is increased from two to three, the number of fuzzy control rules is just increased by two. Three dimensional look-up table is used to reduce the computational time in real-time control, and a technique reducing the amount of necessary memory is introduced. Simulation and experimental studies show that the position errors at the steady state are decreased more than 90% compared to those of existing fuzzy controller when the proposed fuzzy controller is applied to the 2 axis direct drive SCARA robot manipulator.

Control Algorithm for PMSM using Rectangular Two Hall Sensors Compensated by Sensorless Control Method (센서리스 제어 기법에 의해 보완된 두 개의 구형파 홀센서를 이용한 PMSM 제어 알고리즘)

  • Lee, Jung-Hyo;Lee, Taek-Ki;Kim, Young-Ryul;Won, Chung-Yuen
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.5
    • /
    • pp.40-47
    • /
    • 2012
  • The PMSM position sensor using two rectangular hall sensors can restrictively acquire the 90[$^{\circ}$] position information of rotor according to electrical angle. Thus, the control method using this position sensor cannot react properly to a rapid load torque change. On the other hand, even though a sensorless method has the advantage of acquiring instantaneous rotor position information, the accuracy of position sensor can be determined by the gain value of estimator. This paper suggests a robust speed control method on torque fluctuation condition, which combines low cost two rectangular hall sensors and sensorless control method.

A PI-PD Controller Design for the Position Control of a Motor (전동기 위치 제어를 위한 PI-PD 제어기 설계)

  • Jang, Ju-Hyeong;Kim, Sang-Hoon
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.22 no.1
    • /
    • pp.60-66
    • /
    • 2017
  • This paper presents the design of a proportional-integral (PI)-proportional-derivative (PD) position controller without using a speed controller in motor drive systems. Unlike the existing PI-PD position controller design methods, the proposed controller is designed by reducing the entire position control system to a second-order transfer function. Thus, the gain values for the PI-PD position controller can be determined easily by a given bandwidth of the position controller. The PI-PD position controller designed by the proposed method is adopted for position control in an interior permanent magnet synchronous motor drive system to confirm the validity of the proposed design method. The effectiveness of the proposed design method is confirmed through experiments.