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As a common control method for blades, variable pitch technology is used to regulate the output power of the turbine in region 3. To cope with the random variation of wind speed, a novel pitch angle controller is designed in this paper. The proposed method applies a selfcoupled PI (SC-PI) to obtain the desired speed tracking performance, and employs an adaptive neuro-fuzzy inference system (ANFIS) to compensate the controller for disturbance damping capability. A contrast experiment with a baseline PI is conducted in Matlab/Simulink. The performance superiority of the proposed hybrid control method is thus confirmed.

With the rapid development of social economy, power supply reliability of the distribution network has become particularly important. The distribution network has long been faced with problems such as overvoltage, single‐phase grounding failure and grounding protection. Passive, active, and hybrid arc suppression devices (ASDs) are proposed to solve these problems. Passive ASDs have the advantages of high reliability, low control complexity and good economic benefits, and have been widely used in distribution networks. With the wide application of power electronic components in distribution network, the active part and harmonic part of ground current, which cannot be effectively eliminated by passive ASDs, increase sharply. Therefore, an active arc suppression method is proposed. However, due to the high cost and low reliability of the active equipment, the hybrid ASD has better arc suppression effect. In this paper, the existing ASDs are reviewed, and specific simulation models are established to verify the principle and performance of three different ASDs. The advantages and disadvantages of the three ASDs are compared in detail, and the possible problems and research directions in the future research of arc suppression technology are prospected. [ABSTRACT FROM AUTHOR]

To improve the flexibility of the multilevel space vector pulse width modulation (SVPWM), various algorithms have been developed. A theoretical comparison is made for three 2-D SVPWM algorithms: they are g-h frame, α' - β' frame and multilevel SVPWM based on two-level (α* - β* frame). The aim is to provide a guideline for the selection of the most appropriate SVPWM technique for digital implementation. Among them, the α' - β' frame offers the best flexibility with the least calculation and is well suited for digital implementation. The α* - β* frame is the most intuitionistic but has the largest calculation. New general methods of the g-h frame and α' - β' frame for any level SVPWM are also provided, which needs only the angle θ and the modulation depth m to generate and arrange the final vector sequence. All three methods are implemented in a field programmable gate array (FPGA) with very high speed integrated circuit hardware description language (VHDL) and compared in terms of implementation complexity and logic resources required. Simulation results show the absolute advantages of α' - β' frame in briefness and resources use. Finally, an experimental test result is presented with a three-level neutral-point-clamped (NPC) inverter. [ABSTRACT FROM AUTHOR]