Power electronics and renewable energy are two important topics for today's power engineering students. In many cases, the two topics are inextricably intertwined. As the renewable energy sector grows, the need for engineers qualified to design such systems grows as well. In order to train such engineers, new courses are needed that highlight the unique engineering challenges presented by renewable energy systems. This paper presents the theory, implementation, and assessment of a new laboratory course designed to teach power electronics and renewable energy to engineering students. A key element of the course is the use of real renewable energy systems in the laboratory setting. Students design, test, and troubleshoot power electronic circuits (such as dc/dc converters and pulse-width-modulated inverters) with tools used widely in industry (such as MATLAB/Simulink and dSPACE digital signal processors). Ten unique experiments are presented, as well as detailed descriptions of two open-ended design projects: a maximum power point tracker for a photovoltaic array and a full converter for a permanent-magnet wind turbine. Results from students' work on the experiments and final projects, as well as an assessment of the effectiveness of the course based on pre-and post-testing, are also presented.Index Terms-ac/dc power converters, converters, dc/dc power converters, electrical engineering education.

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The North American Electric Reliability Corporation (NERC) envisions a smart grid that aggressively explores advance communication network solutions to facilitate real-time monitoring and dynamic control of the bulk electric power system. At the distribution level, the smart grid integrates renewable generation and energy storage mechanisms to improve the reliability of the grid. Furthermore, dynamic pricing and demand management provide customers an avenue to interact with the power system to determine the electricity usage that best satisfies their lifestyle. At the transmission level, efficient communication and a highly automated architecture provide visibility in the power system and as a result, faults are mitigated faster than they can propagate. However, such higher levels of reliability and efficiency rest on the supporting communication infrastructure. To date, utility companies are moving towards Multiprotocol Label Switching (MPLS) because it supports traffic engineering and virtual private networks (VPNs). Furthermore, it provides Quality of Service (QoS) guarantees and fail-over mechanisms in addition to meeting the requirement of non-routability as stipulated by NERC. However, these benefits come at a cost for the infrastructure that supports the full MPLS specification. With this realization and given a two week implementation and deployment window in GENI, we explore the modularity and flexibility provided by the low cost OpenFlow Software Defined Networking (SDN) solution. In particular, we use OpenFlow to provide 1.) automatic fail-over mechanisms, 2.) a load balancing, and 3.) Quality of Service guarantees: all essential mechanisms for smart grid networks.

Transient and harmonic stresses in wind turbine rotor shafts contribute to gearbox failure. This paper investigates the reduction of rotor shaft torsional vibrations through active control of the generator torque. A 5 MW turbine model is used to test the procedure. A model of a permanent magnet synchronous generator is included as part of the wind turbine simulation. The simulations are carried out using the software FAST from the National Renewable Energy Laboratory (NREL). The PI and feedback linearized controller for the generator is derived together with the means for vibration isolation. Examples of steady, time varying, and turbulent wind are presented which all show significant reduction in the torsional oscillations.