RuggedCom Ethernet Switches Used in Novel Wave-Farm Power Generation Application
Objective
Generate Renewable Electricity from Ocean Waves.
Solution
Use a Novel Articulated Structure and Advanced Control System to Transfer Wave-Induced Motion to Electrical Energy, Enabled by a Rugged Ethernet Network Utilizing the RuggedSwitch™ RS900.
Customer Requirements
Ocean Power Delivery (OPD) is building the world’s first commercial wave-farm to generate renewable electricity from ocean waves off the coast of Portugal. When complete, this 22.5MW project is expected to meet the average electricity demand of more than 15,000 Portuguese households and displace more than 60,000 tonnes of carbon dioxide emission per year from conventional generating plants.
This wave farm uses the Pelamis Wave Energy Converter, a semi-submerged, articulated structure composed of cylindrical sections linked by hinged joint modules. The wave-induced motion of the hinged joints is transferred to a hydraulic motor system which drives electrical generators to produce energy. Several Pelamis can be connected together and linked to shore through a single seabed cable, with power from all the joint modules fed down this cable.
A dynamic mooring system, comprising of a combination of floats and weights, moves the machine to swing head-on to oncoming waves and keeps the Pelamis in position. Also, a “tuneable” and controllable joint module configuration is used to optimize the power capture based on the current wave conditions present in the ocean.
The RuggedSwitch™ RS900 was selected to provide the communications backbone for the sophisticated automation system that controls the operation of the entire structure. Since these switches are located directly on the cylindrical structure, the ability to withstand “harsh” environments, including wide temperature variations and vibration, is a key requirement.
Each Pelamis uses several RS900s. One is installed in each joint module and a further two are used in the nose to provide a network loop architecture. Onshore, several more are installed at the substation to complete the network. The network is designed such that a failure in any area of the network can be recovered quickly to avoid any downtime or adverse affects to the control system. A key requirement for the system is fast network fault recovery which is provided by RuggedCom’s industry leading enhanced Rapid Spanning Tree Protocol (eRSTP™). This feature allows fast network fault recovery on the order of 5ms per hop.
In addition to the ruggedness and reliable features of the RS900, RuggedCom was selected as the preferred vendor because of our ability to provide superior local support and our willingness to commit to a long term business relationship. At RuggedCom we believe in true customer intimacy where we work together with our customers to solve their toughest communications challenges. With RuggedCom as the recognized industry leader in communications products for the electric utility market worldwide, RuggedCom is proud to support this new novel power generation initiative and technology.
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