Explore the vast range of titles available.

This study presents an improved sliding mode model reference adaptive system (SM-MRAS) speed observer for the fuzzy control of direct-drive wind power generation system with a permanent magnet synchronous generator (PMSG). The SM-MRAS speed sensorless observer is described and the corresponding algorithm is derived. The designed fuzzy controller is compared with the conventional PI controller by simulations and experiments. A dc motor is controlled to simulate the wind turbine and an active machine-side converter with space vector pulse width modulation control is adopted to realise the maximum power extraction. A 250-W PMSG experimental platform is built and the experiment results verify the validity of the proposed SM-MRAS speed observer.

Recently, several single-stage buck–boost inverters, such as Z-source inverter (ZSI), Luo-source inverter and Cuk-source inverter, have been developed. These inverters are considered as discontinuous energy pump-source inverters (DEPSI), since these inverters benefit from a pump circuit with discontinuous output voltage as front-end stage. Considering the concept, this study adds two new converters (Zeta and Forward-source inverters) to this family and compares DEPSIs (including already investigated and the presented inverters) and two-stage converters using DC/DC converter as the boost stage regarding several criteria: 1 – boost capability, 2 – cost, 3 – efficiency and 4 – passive components requirement. The results are discussed to determine the appropriate topology according to different voltage gains. Also, a new control algorithm called minimum constant boost control for optimum control of Luo, Cuk and Zeta source inverters has been proposed here, which is used in the analysis and comparison. Experimental tests for a 250 W prototype of the converters are performed, which confirm the simulations and theoretical results.