Large wind farms can have tens or hundreds of wind turbines working together. In order to ensure the wind farm operates safely, reliably and economically, a SCADA (Supervisory Control And Data Acquisition) system is necessary for the monitoring and trouble-shooting of the whole wind farm. SCADA systems acquire and process data collected from the wind farm and individual turbines to ensure the highest efficiency and safety - automatically or under the instructions of operators. A typical SCADA system consists of RTUs (Remote Terminal Units) and a working station.
RTUs are mainly responsible for acquiring data and implementing control. They receive data through different interfaces that indicate real-time information such as turbines status, active/reactive power, environmental conditions inside nacelles, substations’ status, and weather conditions across the wind farm. They then send the data to the working station via Ethernet so that operators could give instructions back to RTUs to implement various operations such as starting and shutting down turbines, testing and resetting, as well as manipulating sub-systems including yaw control, pitch control and generator control. The human-machine interfaces installed on each RTU can be used for on-site control by operators when necessary. Additionally, RTUs are capable of shutting down turbines automatically when operational parameters are exceeded.
Working stations are composed of data servers, network devices and human-machine interfaces. They are the control centres that monitor general information such as installed capacity, operating status and weather condition of the wind farm, manage wind turbines with a graphical topology, and provide authorized users with web access to system through Internet. Furthermore, they have capabilities for generating statistics, importing and converting topographic maps, and implementing synchronization between each virtual turbine and the associated physical one.