• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.1040-1048
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• 2013

In this paper, a sensorless pitch angle control method for a wind generation system is suggested. One-step-ahead prediction control law is adopted to control the pitch angle of a wind turbine in order for electric output power to track target values. And it is shown that this control scheme using the inverse dynamics of the controlled system enables us to predict current wind speed without an anemometer, to a considerable precision. The inverse input-output of the controlled system is realized by use of an artificial neural network. The proposed control and wind speed prediction method is applied to a Double-Feed Induction Generation system connected to a simple power system through computer simulation to show its effectiveness. The simulation results demonstrate that the suggested method shows better control performances with less control efforts than a conventional Proportional-Integral controller.

• Journal of Power Electronics
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• v.11 no.4
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• pp.464-470
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• 2011

In this paper, the feasibility of applying a position sensorless control technique to hybrid electric vehicles (HEVs) is practically evaluated. The proposed position estimator has a straightforward structure with properties that combines the model and the saliency tracking-based rotor position estimation for interior permanent magnet synchronous motors (IPMSMs). The proposed method can be used in the event of sensor loss or sensor recovery to sustain continuity of operations. The developed system takes into account the estimated position transition between two distinct sensorless methods. The transition is enhanced by introducing a synchronized transition algorithm based on a single tracking observer. Extensive experimental results are presented to verify the principles and show a reliable estimation performance over the entire speed range including standstill under 150% load conditions.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.523-525
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• 2006

Adaptive neural state-feedback controllers for the fully nonaffine pure-feedback nonlinear system are presented in this paper. By reformulating the original pure-feedback system to a standard normal form with respect to newly defined state variables, the proposed controllers require no backstepping design procedures. Avoiding backstepping makes the controller structure and stability analysis considerably to be simplified. The proposed controllers employ only one neural network to approximate unknown ideal controllers, which highlights the simplicity of the proposed neural controller.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2292-2294
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• 2002

This paper presents the network of Distributed Control System(DCS) considering specification of nuclear power plant. The network is composed of field network, control network and information network. The protocol of control network is ring type and it is compared to ethernet type. This paper proposes the structure of DCS, the protocol of each network and analyzes the network traffic along data capacity of field network, control network, information network and the network performance. Network II.5 is used as traffic simulation tool.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.7
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• pp.21-31
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• 1996

An intelligent integrated control system is designed for the active steering and the left/right traction force distribution control of electric vehicles, where input-output linearization is employed. Also, a fuzzy-rule-based cornering force estimator is suggested to avoid using an uncertain highly nonlinear expression, and a neural network compensator is additively utilized for the estimator to correctly find cornering forece. With these techniques, the proposed control system is shown by simulation results to be robust against drastic change of the external environments such as road conditions.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.22-25
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• 2000

This paper introduces the ship propulsion system in different aspects. In fact there are many types to accomplish electric propulsion. The latest installations are based on fixed generator speed and motor speed control. The AC motor drive systems with synchroconverter cycloconverter PWM converter are chosen for the ship electric propulsion. The configurations of the ship electric propulsion. The configurationso of the ship electric propulsion system must be considered about following criteria : torque and speed performances redundancy cost harmonics available space and shape. This paper introduces possible configurations of the ship electric propulsion and the major and minor points.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1441-1444
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• 1996

This paper presents the position control of a double-rod cylinder system activated by an electrotheological(ER) valve unit. Following the composition of a silicone oil-based ER fluid, theological properties of the ER fluid are experimentally tested as a function of imposed electric fields to determine appropriate design parameters of the ER valve. The ER valves are then designed and manufactured. Subsequently, the pressure drop of the ER valve is evaluated with respect to the intensity of the electric field. Four ER valves bridge-cylinder system is formulated, and the governing equations for the system are derived. A neural network control scheme is then synthesized to perform the position control of the cylinder system. Tracking control responses are experimentally evaluated and presented in order to demonstrate the effectiveness of the proposed control system.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1387-1390
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• 2005

Recently, foreign utilities emphasize the importance of the value-added services based on Information Technology(IT) as one of the strategic technologies for establishing a new power system in the future digital society. They develop many different types of the value-added services and apply the systems for customer. In domestic case, the data from the Automatic Meter Reading (AMR) System is used only for calculating the tariffs. Data from the AMR system can be strategic assets for utilities to provide the value-added services for customer. Development of the value-added services for utilities and customer needs processing and managing the AMR data. In this paper, the energy consulting service, which is adequate to new power system environment, is suggested for development of the value-added services. The application of the suggested service will bring the effect of reducing the monthly bill for customer. Also the service will give not only the effective demand side management(DSM) and load control, but also reduction of the investment for utilities.

• The Transactions of the Korean Institute of Power Electronics
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• v.25 no.5
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• pp.404-411
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• 2020

Inductive power transfer (IPT) systems for electric vehicles generally require zero phase angle (ZPA) frequency tracking control to achieve high efficiency. Current sensors are used for ZPA frequency tracking control. However, the use of current sensors causes several problems, such as switching noise, degrading control performance, and control complexity. To solve these problems, this study proposes ZPA frequency tracking control without current sensors. Such control enables ZPA frequency tracking without real-time control and achieves stable zero voltage switching operation closed to ZPA frequency within all coupling coefficient and load ranges. The validity of the proposed control algorithm is verified on LCCL-S topology with a 3.3 kW rating IPT experimental test bed. Simulation verification is also performed.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1331-1333
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• 1999

In Haenam-Cheju HVDC link several modes of operations and controls are provided, which are constant frequency control, constant power control and constant current control. This paper describes basic control action of converters under three control modes and shows EMTDC simulation results at ground fault and steady state respectively.