• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.113-118
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• 2014

Tidal power is one of new and renewable energy sources. Tidal power is generated by using the gap in the water level between the water outside and inside the embankment. All tidal power plant in Korea were being operated by import of turn-key from abroad. The know-how and technology which are the most important to build predictive control system has become increasingly difficult to obtain from advanced countries because most of them avoid to transfer, which the domestic development of the control system is needed. In this paper, a study on start stop system at water turbine-generator for tidal power plant at the beginning of development was presented. For improvement the efficiency and develope of core technology of the start stop system, the technique and characteristics of tidal power, modeling, maximum generation calculation method, and optimal control of joint control system in Sihwa tidal power plant were studied.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.2
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• pp.89-94
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• 2014

Tidal generation has become one of environmentally friendly new and renewable future sources of energy. The Sihwa Tidal Power Plant in South Korea, which was imported from abroad by turnkey type in 2011, connected to the power system in 2012, and is currently under commercial operation. However, leading companies are reluctant to disclose their technologies associated with the control systems and are not cooperative in technology transfers, making it a high priority to develop core technologies in South Korea. In order to develop a start stop control system for tidal generation, this paper presents the optimal algorithm for decision making and prototype of hardware design. First, control systems in tidal power, such as plant operation control, data interfaces between systems, monitoring and control points of the control system, are analyzed. The software development and PC based emulator processes for optimization algorithm processing are described. Finally, verification of the algorithm implementation, hardware platform for start stop control device, and implementation of prototype control system were discussed.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.1
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• pp.16-21
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• 2018

This work aims to develop a platform to investigate the effect of operation schedules on the building energy consumption and to derive a simulation model based optimal start and stop daily strategy. An open-source building energy simulation tool DOE2 is used for the engine, and the developed simulation model is validated using ASHRAE guideline 14. The effect of late-start/early-stop operation of HVAC system on the daily building energy consumption was analyzed using the developed simulation model. It was found that about 10% of energy consumption cut was possible using the control strategy for an hour of advance of the stop operation, and about 3% per an hour of delay of the start operation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.6
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• pp.106-112
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• 2014

Recently, tidal power generation has gained much attention. South Korea's tidal power generation systems were imported from abroad by turnkey type and have being operated. Therefore, for efficient operation and technological independence of a tidal power system, development of core technology is required. This paper deals with the start stop control system of water turbine generator in the tidal power plant, as one of our development project results. Using the SCADA system, the status and operations of water turbine generator in the tidal power plant, as well as simulation for calculation of maximum power were carried out. A small model type of start stop control device was also developed. In addition, the control system in Sihwa tidal power plant was modeled, and the results obtained by the dynamic simulation were given in graphics by 2D simulator.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.584-589
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• 1994

A time-varying nonlinear mathematical model was derived to consider the effect of change in roll radius on tension varation during winding and unwinding. A variable-gain PID controller was designed for tension control at start and stop in a multi-span continuous process system. The controller gains are updated at every control loop as roll radii continuously change. Computer simulation was carried out by using the mathematical model and the controller developed for a typical operating condition including acceleration and deceleration. When the variable-gain PID controller was used, the tension control performance was improved compared with that of existing control method during start-up and stop.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.2
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• pp.389-396
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• 1988

Microprocessor-based software DDA interpolator is developed and applied to two axis contouring control of X-Y table. Developed assembly program is composed of feedrate, linear and circular DDA interpolation routines. Reference-pulse type of open-loop stepping motor control system in which the micro-computer produces a sequence of reference pulses for each axis of motion is adopted. To test performance of the developed program, X-Y table drive system based on stepping motor and shaft encoder is designed. Conturing error of the system in linear and circular path is within .+-. 0.2mm under start stop pulse rate of stepping motor.

• Journal of the Korea Society of Computer and Information
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• v.28 no.5
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• pp.1-8
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• 2023

In this paper, we implement a control system for an IoT-based backpack type vacuum cleaner using a smart device such as a smart phone or smart watch. The implementation system consists of control module produces, control module programming, and smart device programming. The control module is made of Arduino Nano, HM-10 BLE(Bluetooth Low Energy) module and relays as basic parts. The smart device exchanges signals with the control module via bi-directional BLE communication, which allows it to control the start/stop of the vacuum cleaner. Backpack type vacuum cleaners are effective for cleaning high places that require the use of ladders. However, it is often necessary to take off the backpack type cleaner to start/stop it. The IoT-based vacuum cleaner control system implemented in this paper fundamentally solves the problem by allowing users to control the start/stop of the vacuum cleaner without taking it off.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.18 no.4
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• pp.33-44
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• 2022

In this study, we analyze the existing heating and cooling operation method for an office-type complex building with a central heating and cooling system, and examine the effects of applying various EMS that can be applied according to the load size to save energy in the building. For this purpose, simulation analysis was performed. As a control method, reset control of chilled water, hot water, cooling water and supply air temperatures, optimal start/stop of heat source, and number of heat source control were applied according to the load size, and energy consumption was analyzed accordingly. In addition, when all of these control methods were applied, the overlapping energy saving effect was finally confirmed. As a result, it was possible to confirm the energy saving effect when EMS for reset control and heat source control were applied compared to the existing control method of the heating and cooling system, and the effect for the case of using all these control methods in combination was also confirmed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.1122-1129
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• 2001

In this work, we propose a new type of HDD suspension featuring shape memory ally (SMA) actuator in order to prevent the contact between the slider and disk. The principal design parameters are obtained from the modal analysis using finite element analysis, and then the dynamic model is established to formulate the control scheme for Non-Contact Start/Stop mode drive. Subsequently, a robust Η$_{\infty}$, control algorithm is designed by integrating experimentally-obtained SMA actuator dynamics to the proposed suspension system. The controller is empirically realized and control results for different load/unload profiles are presented in time domain. In addition, the contact signal between the slider and disk is measured by the electrical resistance method.istance method.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.6
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• pp.66-78
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• 1978

An assembly package program is developed for a computerize4 operation of a drilling machine system utilizing a microprocessor. Different drilling instruction requires merely the input of different sets of input data. To make pulse motors to follow their input pulse trains with fidelity, an optimum start-stop rate matrix is proposed, whose elements are determined according to the pulse motor torque and the load inertia of the mechanical system composed of a workpiece and a worktable.