Dielectric elastomers used as generators have received considerable attention lately and several prototypes were built to demonstrate the process. The aim of the paper is to show how an innovative energy harvesting cycle can be realized to use the DEs as an efficient generator. It investigates the effects of (dis)charging instants, the current amplitude and how the parasitics of the material influences the energy gain and show what kind of trade-offs can be reached by selecting parameters carefully. Also an EAP emulator is introduced: it is able to implement a variable capacitor by a controllable power supply. It can be used for evaluating PTOs, tests, measurements; without the complexity, vulnerability and high price of the elastomer.@en

EeFarm-II is used to evaluate 13 different electrical systems for a 200 MW wind farm with a 100 km connection to shore. The evaluation is based on component manufacturer data of 2009. AC systems are compared to systems with DC connections inside the wind farm and DC connection to shore. Two options have the best performance for this wind farm size and distance: the AC system and the system with a DC connection to shore. EeFarm-II is a user friendly computer program for wind farm electrical and economic evaluation. It has been built as a Simulink Library in the graphical interface of Matlab-Simulink. EeFarm-II contains models of wind turbines, generators, transformers, AC cables, inductors, nodes, splitters, PWM converters, thyristor converters, DC cables, choppers and statcoms.@en

Dielectric Elastomers are well known for there performance as actuators, but these materials can be used effectively as generators. Research on this field have received considerable attention lately, several prototypes were built like wavepower and human kinetic power generators. The focus of this paper is how the dielectric elastomer can be used as generator. The paper presents a dynamic model to calculate the capacitance of the electroactive polymer according to the external loading and investigates and compares several energy harvesting cycles based on the energy gain.@en

From an electrical point of view dielectric elastomers are variable capacitors, which are frequently used as generators. The focus of this paper is to show, how the maximum energy gain can be realized by realizing an innovative current waveform to charge and discharge the polymer. Several energy harvesting cycles are introduced and their energy output compared. The most promising cycle has been optimized to increase its production while taking several limiting factors into account.

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Abstract To increase the clean and renewable energy used presently, energy could be extracted from the sea. Here an Archimedes Wave Swing (AWS) park is proposed to convert the motion of the sea waves into electricity with a capacity of 90 MW. In order to find the most suitable way to connect these devices, various electrical components are used which need to be modeled precisely to carry out the calculations and simulations. Several different topologies are implemented by linking up the devices to each other and to the electrical network and they will be evaluated according to important electrical and economical factors. The interest lies primarily in identifying farm configurations with a low cost profile and high efficiency.@en