• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.877-887
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• 2015

In this paper, a design of communication joint tools to implement a legacy-line communication (LLC) system, which exploits various conductive lines in a train, is presented. We develop two kinds of joint tools; one is a conductive joint tool (CJT) that is connected directly to the conventional lines and the other is the inductive joint tool (IJT) which connects the conventional lines indirectly using electromagnetic induction. As a result, the practical experiment of data communication confirms that an LLC system with the developed joint tools has a transmission rate more than 20 Mbps in the distance of 200 m away. In addition, an environmental durability test shows that the joint tools operate stably in an extreme environmenal variation. It is, therefore, considered that the developed joint tools are very useful to implement a communication network in the train working currently.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.8
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• pp.1831-1838
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• 2015

In this paper, a method of implementing a communication network in ship, which exploits a powerline-based legacy-line communication system (LLC), is presented. We develop an inductive coupling unit and a multi-interface device to connect a data communication terminal to the powerline. As a result of operation tests for the ship under working, the implemented LLC shows a transmission rate of at least 25.8 Mbps in the distance of 200 m away with 100% success rate. Thus, the system can be a useful alternative to implement a communication network in ship without additional channels. Being easy to be implemented and supporting various interfaces for data communication, the presented system will be very effective when a real-time monitoring system is launched in future digital ship.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.4
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• pp.336-341
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• 2016

This paper presents an implementation of a communication network in wind turbines, which exploits the power-line communication system (PLC). We used an inductive coupling unit and a multi-interface device to connect a data-communication terminal to the power line, to ensure that stable communication was possible at various electric current and voltage values of the generator. The results of the operation tests conducted on an operational wind turbine showed that the implemented PLC demonstrated a transmission rate of at least 43 Mbps with a 100% success rate. Moreover, a real-time image was transmitted. Thus, the system could be a useful alternative for implementing a communication network in wind turbines that does not require additional channels. Since the presented system is easy to implement, and can support various interfaces for data communication, it will be quite useful when a real-time monitoring system is launched in wind turbines.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.292-297
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• 2015

In this paper, we reported the bypass unit for ship area networks in order to detour the communication failure regions and poor communication links. The device was composed of three parts of circuits for power cut-off, protection, and coupling transformer. Since the coupling transformer exerts a dominant influence on the performance of the by-pass unit, we have tried to find the optimal magnetic core materials and its dimensions. The prototype was passed through the performance test of insertion loss, temperature, and vibration characteristics. The insertion loss was around -2 dB in the range of 90 kHz ~ 30 MHz and the average communication speed was 59.2 Mbps in the laboratory. A pilot communication test using the developed tool was conducted in the training ship of the Korea Maritime and Ocean University. As a results of experiment, we showed that the wired communication among the heterogeneous-links in the ship area networks are possible by the bypass unit and also a high speed communication services are available in ~ Mbps by using a power-line.

• Journal of Navigation and Port Research
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• v.40 no.3
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• pp.159-164
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• 2016

The goal of this study is to implement a communication system that can monitor the status of the nacelle using the power cable itself, without the dedicated communication lines such as an UTP cable and optical fiber for the offshore wind turbine. An inductive coupling powerline communication system for a MW class offshore wind turbine was proposed and its communication performance was demonstrated. The inductive couplers was designed for operation at up to 500 A using a ferrite composite materials. Field test was carried out on the wind farms of Jeju island. Using the iperf communication test program, we have obtained more than 15 Mbps data transmission rate through the 100 m power cable that was installed between the nacelle and the bottom of the power converter. In the data transmission stability test for a week, there was no failure ever. The minimum transmission rate was 15 Mbps and the average data rate was about 20 Mbps. Next, we have installed an infrared camera inside the nacelle in order to measure the temperature distribution and variation of the nacelle. The real-time thermal image taken by the camera was successfully sent to the monitoring system without error.