• Journal of Institute of Control, Robotics and Systems
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• v.3 no.6
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• pp.639-643
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• 1997

This paper presents how nonlinear PID control algorithms can be applied on chemical processes for a more stable operation and perfect automation. A pass balance controller is designed to balance the exiting temperatures of a heater and a heat exchange network. The proposed controller has gain-varying integral action and deals with the operational constraints in an efficient manner. Also, the use of a PID gap controller is proposed to maximize energy saving and operation stability and to minimize operator intervention in operation of air fan coolers. The proposed controller adjusts the opening of a louver automatically in such a way that it keeps the air fan pitch position within the desired range. All these nonlinear PID controllers have been implemented on the distributed control system (DCS) for good reliability and operability. Operator acceptance was very high and the implemented controllers have shown good performance and high service factor still now on. The proposed methodology can be directly applied to similar processes without any modification.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.133-143
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• 2023

This paper describes the system integration laboratory's requirement analysis, implementation, and verification for multiple-scenario unmanned aerial vehicle operation and control technology using a manned rotorcraft for Manned-Unmanned Teaming. System integration laboratory consists of manned rotorcraft flight simulation, unmanned aerial vehicle flight and mission equipment simulation, ground control system simulation for unmanned aerial vehicle control and change in the control authority between the ground control system and manned rotorcraft, and operation and control system for mission plan's writing and transmission. Each implemented simulation verified the requirements through software and hardware integration test.

• Journal of Advanced Navigation Technology
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• v.27 no.2
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• pp.173-181
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• 2023

Aircraft carriers need to maintain an orderly flow of aircraft in order for military ships to conduct combat through aircraft. Maintaining aircraft flow is an important factor in strengthening ship and aviation safety. In order to maintain aircraft flow, it is essential to develop a state-of-the-art air control system that provides higher quality control information by simultaneously accommodating radar-based monitoring information and monitoring information based on CNS integrated technology. Based on this point, this study describes the function and operation method of specific control equipment for the operation of the Aviation Support System and Air Traffic Control System required to operate light aircraft carriers in Korea based on overseas cases.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.340-343
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• 1992

Fundamental positioning characteristics of a dual-axis Sawyer linear motor are described. The Sawyer motor is capable of high positional accuracy. An electronic control unit of the motor whose velocity is proportional to the frequency of the electric current was produced in our laboratory. The positioning system was constructed using two Sawyer motors, an air bearings suspension unit and an electronic control unit. The stable motion of the motor was confirmed on the open loop operation. The adjustable operating conditions were the live load of 1 kg, the maximum acceleration of 1.2G and the maximum velocity of 350 mm/s. Absolute positioning accuracy was improved within .+-.5.mu.m, on microstep operating conditions of dividing one pitch of 508.mu.m into 508 steps. The following two conclusions were obtained. An accelerating-cruising-decelerating control is effective for reduction in the travel time required. Also, microstep operation is effective for improving the resolution of position.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.3
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• pp.200-206
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• 2016

In the microgrid, inverters for energy storage system are generally constructed in a parallel structure because of capacity expandability, convenience of system maintenance, and reliability improvement. Parallel inverters are required to provide stable voltage to the critical load in PCC and to accurately share the current between each inverter. Furthermore, when islanding occurs, the inverters should change its operating mode from grid-connected mode to stand-alone mode. However, during clearing time and control mode change, the conventional control method has a negative impact on the critical load, that is, severe fluctuating voltage. In this study, a parallel operation control method is proposed. This method provides seamless mode transfer for the entire transition period, including clearing time and control mode change, and has accurate current sharing between each inverter. The proposed control method is validated through simulation and experiment.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.314-316
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• 1994

The operation of RC(Rod Consolidation) technology carry out highly radiation environment. It requires remote operation and automation for efficient handling and for minimizing radiation exposure to the operator. So we investigated up and down position control of shock absorber device in RC system. To verify the research experimentally, a RC system was set up and PI control method was applied. Fuzzy control method was also tested to further improve control behavior.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.6
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• pp.932-938
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• 2009

As a stringing troy wire is installed by manual operation, it is necessary to scheme the automatic system for stringing troy wire. To accomplish a task of this kind, in this paper an approach to designing controllers for the hybrid Position/Tension control of a stringing troy wire is presented. Position control system is designed based on equation of dc motor and motion equation of robot, it is controlled by feedback with a detected speed dc motor. Tension control system is designed based on equation of ac servomotor for generating torque and dynamic equation of a troy wire, it is controled by feedback with a detected tension. The control parameters is determined by simulation in independence operation of each system. To suppress a mutual interference that the disturbance occur in operating of two task at same time. Dynamic hybrid control is proposed by feed forward compensator with a disturbance accelerator and a step torque at start. The operation of proposed system is simulated and experimented, results is verified the utilities.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2052-2056
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• 2015

This Paper analyzes the characteristics of the WRSM in high-speed operation range. To verify the control characteritics of various WRSM models, the relative position of the central point of current limit circle and voltage limit ellipse is defined as M value and 3 models according to M_max value are designed through inductance change. Through the designed models, the current control method of 3-variables control for maximum power especially in high-speed operation range is presented.

• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.1212-1220
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• 2013

In general, for a large power system like DC distribution system for buildings, several power converters are modularized for parallel operation. However, in parallel operation, inconsistency of parameters in each module causes circulating current in the whole system. Circulating current is directly related to loss, and, therefore, it is most important for the safety of the power system to supply the suitable current to each module. This paper proposes a control method to reduce circulating current caused during parallel operation. Accordingly, the validity of parallel operation system including response characteristics and normal state was verified by simulation and experiment result.

• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.171-177
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• 2012

The autonomous microgrid is a system that is autonomously operated depending on the grid and internal load condition, without the operator's intervention. In this study, a control algorithm for the microsource and an operation algorithm for the microgrid are proposed to realize the autonomous microgrid system. In addition, a microgrid operation system based on the operation algorithm is proposed. The electromagnetic transient program is used by the proposed microsource control algorithm for simulation, and the validity of the algorithm is verified. The proposed operation system is verified based on a case study using a simulator and test devices.