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This paper develops a novel single-switch resonant power converter for renewable energy generation applications. This circuit topology integrates a novel single-switch resonant inverter with zero-voltage switching (ZVS) with an energy-blocking diode with zero-current switching (ZCS). The energy-blocking diode with a direct-current output filter filters the output stage of the novel single-switch resonant inverter. Only one active power switch is used for power energy conversion to reduce the cost of active power switches and control circuits. The active power switch is controlled by pulsewidth modulation at a fixed switching frequency and a constant duty cycle. When the resonant converter is operated at discontinuous conduction mode, the inductor current through the resonant tank could achieve ZCS of the energy-blocking diode. Accordingly, a high energy conversion efficiency is ensured. Operating principles are derived, and analyses are carried out based on the equivalent circuits for the proposed power converter under different operating modes. The operating principles of the converter were verified using a 32.4-W 70-kHz experimental photovoltaic-powered load system. Given appropriately chosen circuit parameters, the active power switch can be operated with ZVS, and a measured energy conversion efficiency of the proposed topology of 97.3% can be achieved. Experimental results demonstrate a satisfactory performance of the proposed topology, which is particularly suited to the energy conversion applications in renewable energy generation systems. [ABSTRACT FROM PUBLISHER]

Among the many advantages that resonant power conversion has over conventionally adopted pulse-width modulation include a low electromagnetic interference, low switching losses, small volume, and light weight of components due to a high switching frequency, high efficiency, and low reverse-recovery losses in diodes owing to a low di/dt at switching instant. This work presents a novel loaded-resonant converter for direct currennt (dc)-to-dc energy conversion applications. The proposed topology comprises a half-bridge inductor-capacitor-inductor (L-C-L) resonant inverter and a bridge rectifier. Output stage of the proposed loaded-resonant converter is filtered by a low-pass filter. A prototype dc-to-dc energy converter circuit with the novel loaded-resonant converter designed for a load is developed and tested to verify its analytical predictions. The measured energy conversion efficiency of the proposed novel loaded-resonant topology reaches up to 88.3%. Moreover, test results demonstrate a satisfactory performance of the proposed topology. Furthermore, the proposed topology is highly promising for applications of power electronic productions such as switching power supplies, battery chargers, uninterruptible power systems, renewable energy generation systems, and telecom power supplies. [ABSTRACT FROM AUTHOR]

As the consciousness of human beings in preserving the world increases, the demand of alternative energy resources has been expanding exponentially in recent years, and wind power is one of the most promising renewable energy resources. Taiwan, with its abundant coastal wind resources and good geographical conditions, is very suitable for developing wind farms. The development and implementation of renewable energy regulations have defined a direction for future renewable energy development in Taiwan. This also shows Taiwan's determination to follow the footsteps of the developed countries and the commitment to environmental protection. Therefore, the decision making of wind farms has become the most important link for the construction of wind farms in the future. This paper proposed a fuzzy analytic network process with benefit–opportunity–cost–risk approach to systemize the complicated decision making of wind farm site selection. A case study is carried out to examine the proposed approach and to evaluate the performance of several existing wind farms in Taiwan. By adopting the systematic analysis method, the most suitable wind farm can be determined, and the results can be references for planning and development of wind power industry in the future. [ABSTRACT FROM AUTHOR]