• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.73-76
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• 1996

This paper presents a dynamical anti-reset windup (ARW) compensation method for saturating control systems with multiple controllers and/or multiloop configuration. By regarding the difference of the controller states in the absence and presence of saturating actuators as an objective function, the dynamical compensator which minimize the objective function are derived in an integrated fashion. The proposed dynamical compensator is a closed form of the plant and controller parameters. The proposed method guarantees total stability of resulting system. An illustrative example is given to show the effectiveness of the proposed method.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.447-457
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• 1994

This paper presents a compensation method for discrete-time control systems with saturation nonlinearities to cope with the reset windup phenomena. The proposed ARW (Anti-Reset Windup) method is motivated by the concept of the equilibrium point. The design parameter of the ARW scheme is explicitly derived by minimizing a reasonable performance index. The resulting dynamics of the compensated controller exhibits the reduced model form of the unsaturated system which can be obtained by the singular perturbational model reduction method. An example is given to illustrate the effectiveness of the proposed method.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.4
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• pp.417-426
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• 1991

All mechanical systems have saturation nonlinearity in actuators or in final control elements. When controllers have an integral action, reset windup can cause instability as well as make the system performance unsatisfacdtory. This paper presents an analysis of the stability of the control system with antireset-windup limiter, called intelligent limiter, using the describing function method. The responses of the system with this limiter are illustrated by computer simulation.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.5
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• pp.543-550
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• 2014

In many industrial processes and operations, such as power plants, petrochemical industries and ships, shell and tube heat exchangers are widely used and probably applicable for a wide range of operating temperatures. The main purpose of a heat exchanger is to transfer heat between two or more medium with temperature differences. Heat exchangers are highly nonlinear, time-varying and show time lag behavior during operation. The temperature control of such processes has been challenging for control engineers and a variety of forms of PID controllers have been proposed to guarantee better performance. In this paper, a scheme to control the outlet temperature of a shell and tube heat exchanger system that combines the PID controller with feedforward control and anti-windup techniques is presented. A genetic algorithm is used to tune the parameters of the PID controller with anti-windup and the feedforward controller by minimizing the IAE (Integral of Absolute Error). Simulation works are performed to study the performance of the proposed method when applied to the process.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.74-82
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• 2004

This paper describes the speed control of the surface-mounted permanent-magent synchronous motors (SMPMSNM) for elevator drive. The elevator motor needs to be a compact and slim type. Essentially, the proposed scheme uses a vector control algorithm for a speed and torque control and Anti-windup technique is adopted to prevent a windup phenomenon. This system is implemented using a high speed 32-bit DSP (TMS320C31-50), a high-integrated logic device FPGA(EPF10K10TI144-3) to design compactly and inexpensively. The proposed scheme is verified by the results through digital simulation and experiments for a three-phase 13.3[kW] SMPMSM as a MRL(MachineRoomLess) elevator motor in the laboratory.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.457-461
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• 2001

Advantages of switched reluctance motor(SRM) drives make it an attractive candidate for replacing adjustable speed ac and dc drives in both industrial and consumer applications. Furthermore, a simple, low cost and robust SRM drive can be efficiently operated in the hostile environment of an automobile. Generally, the speed control of SRM has a large step change or large torque reference, the output of its PI controller is often saturated. When this happens, the integral state is not consistent with the SRM input, while may give rise to the windup phenomenon. This paper proposes anti-windup control method for SRM speed control system by hysteresis current controlled asymmetry bridge converter. The experimental results show that the speed response has much improved performance, such as a small overshoot and fast settling time at the acceleration and particulary deceleration period with braking mode.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.6 s.144
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• pp.566-574
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• 2005

Reduction of a ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargos as well as improving the comfort of the ride. A mass driving anti-rolling system (MO-ARS) might be one candidate of several systems against the ship's rolling. As the movable range of the mass on the ship is finite, the control system must include restriction on the mass position to protect the device and the ship. This restriction usually causes windup phenomenon and control performance is deteriorated seriously. Two control algorithms, anti-windup control and saturated sliding mode control, are studied in this paper. Control performance and robustness problem are checked out by numerical simulations.

• International Journal of Automotive Technology
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• v.7 no.3
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• pp.369-375
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• 2006

This paper describes a simple proportional and integral control algorithm for a swirl motor controller and its application. The control algorithm may be complicated in order to have desired performance, such as low steady state errors, fast response time, and relatively low overshoot. At the same time, it should be compact so that it can be easily implemented on a low cost microcontroller, which has no floating-point calculation capability and low computing speed. These conflicting requirements are fulfilled by the proposed control algorithm which consists of a gain scheduling proportional controller and an anti-windup integral controller. The mechanical friction, which is caused by gears and a return spring, varies very nonlinearly according to the angular position of the system. This nonlinear static friction is overcome by the proportional controller, which has a two-dimensional look up gain table. It has error axis and angular position axis. The integral controller is designed not only to minimize the steady state error but also to avoid the windup effect, which may be caused by the saturation of a motor driver. The proposed control algorithm is verified by use of a commercial product to prove the feasibility of the algorithm.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1793-1794
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• 2007

Since it has an advantage of possibility to control using experimentally given coefficient, PID Control is the most widely used method of control in the field of industry. However, since PID controller is not able to reflect the inherent characteristics of individual systems, it needs to be accompanied by additional techniques to supplement. Also, it has disadvantage that it is hard to find a satisfactory coeffi cient when the state of the system's dynamic characteristics and static characteristics are different each other. When the dynamic one shows up, it means the state of system shows a great amount of difference from that of desired such as the moment of beginning control or change of desired state. But, if the state of the system comes close to the desired state, the static characteristics shows up in the system. There are many solutions suggested to overcome problems according to the conversion of two examples of motion shown above. This paper is to confirm PID control's integration ingredient windup phenomenon, and experiment through technique of pre vention of windup actually using PLC(Programmable Logic Co ntroller), and to verify the change in characteristics of control.

• ICROS
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• v.3 no.5
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• pp.58-64
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• 1997

pH 공정은 비선형이며, 입력흐름의 성분과 농도가 바뀜에 따라 비선형성이 급격히 바뀌는 적응제어가 요구되는 공정이다. 최근 이 공정에 대한 모델링 기법이 확립되고, 매우 작은 수의 변수를 갖는 parameterization이 제안되어 간단한 형태의 우수한 적응제어법이 구성되어 있다. 그러나 estimation의 windup은 선형 시스템의 적응제어법에서와 마찬가지로 큰 문제점으로 남아있다. 본 고에서는 pH 공정의 적응제어법을 간략히 살펴보았으며 좀 더 견실하고 우수한 성능을 주는 방법을 위하여 두 가지 제안을 하였다. 한 제안은 기존의 변수 estimation의 목적함수가 제어기 성능에 직접적이지 못한 것을 바로 잡으려는 것이다. 새로 제안한 것을 적응제어에 바로 이용하는데 아직 걸림돌이 몇몇 남아 있어 연구가 요구되고 있다. 또 한 제안은 estimation windup을 해결하려는 것으로 pH 공정 특성상 나타나는 것으로 바로 pH 공정 적응제어에 이용될 수 있다.