Network of plant remote monitoring system using Web for windfarms

Wind power generation occupies an important position as a new non-fossil energy in recent years, and the plant scale has been rapidly expanding. Wind power plant with over one hundred wind turbines, called wind-farm, has been built in Europe, North America and so on, and the scale of dozens of wind turbines called wind-farm has been built these days in Japan. In many cases, wind-farms are built in topographically inconvenient places in considerations of environment or wind conditions. That is why the equipment has been required for collecting data of troubles and failures while remote controlling and monitoring the turbines by the operation staff. The system monitoring and controlling by way of Internet has been realized. Ethernet had been said to be unsuitable to the industrial network though, it is one of the strong options because of its low cost and easiness to apply to the large-scale wind turbine plants. In this case, it is important to secure the throughput enough for updating data of numerous nodes (each wind turbine on the network) connected to the network within a fixed time. In order to achieve this, the overhead of software should be as small as possible. As its means, we decided to use the multi-thread method, that is one of the parallel processing. This paper presents the relation between the number of threads and total throughputs of network, and the most optimum number of threads in accordance with the above result, and then clarifies the design procedure and the validity of local network used in the large-scaled wind turbine site.