Random variation of grid-connected wind power can cause stochastic variation of the power system operating point. This paper proposes a new scheme to design an adaptive damping controller by tracking the variation of system operating points and updating the controller’s functions to achieve a robust damping control effect. Firstly, the operating space is classified into different modes according to the classification of wind power outputs. Multiple power system stabilizers (PSSs) are then designed. Secondly, the method of optimal classification and regression decision tree (CART) is utilized for classifying subspaces of system operating point and it is proposed that the on-line measurements from wide area measurement system (WAMS) are used for tracking the dynamic behaviors of stochastic drifting point and thus guide the updating of appropriate PSSs be switched on adaptively. A 16-generator-68-bus power system integrated with wind power is presented as a test system to demonstrate that the adaptive control scheme by use of the CART can damp multi-mode oscillations effectively when the wind power output changes.

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The scale parameters of bubbles produced by underwater exhaust influence the effect of the acoustic insulation. According to the dynamic characteristics in the process of underwater exhaust and the design criteria of equal flow per unit area, the two-dimensional equation of underwater exhaust was established. The analytical expressions of the orifice position and geometric parameters of the two-dimensional underwater exhaust device were obtained. The finite element models were established to compare the two vent patterns of uniform distribution and fixed orifice spacing / variable orifice area distribution. The exhaust effect was verified by circulating flume test. The simulation and experimental results show that the fixed orifice spacing and variable orifice area distribution mode can effectively control the distribution of bubbles scale parameters, and enhance the acoustic insulation effect of bubbles.