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Block diagram of the proposed PC. 

Block diagram of the proposed PC. 

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Article
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Passive loading is a suboptimal method of control for wave energy converters (WECs) that usually consists of tuning the power take-off (PTO) damping of the WEC to either the energy or the peak frequency of the local wave spectrum. Such approach results in a good solution for waves characterized by one-peak narrowband spectra. Nonetheless, real ocea...

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Context 1
... aim is to identify the dominant IMF component (in terms of the energy of the signal), and use the information of its instantaneous frequency for tuning the PTO damp- ing. From (11), Figure 2 illustrates the block diagram of the proposed real-time PC based on the HHT approach. The procedure to calculatê ω d is described next. ...
Context 2
... in order to avoid other limitations of the HT (Huang, 2005), the dominant IMF is normalized by dividing it by a spline envelope defined through all the maxima of the IMF, as described in Huang (2005). ...
Context 3
... constant damping at ω e gives greater energy capture than tuning at ω p . The highest differences in the absorption of energy are obtained for sea states S2 and S4. Both sea states are characterized by wideband spectra. Nonetheless, for S2 the high frequency peak (ω p = 1.22 rad/s) is filtered out by the shape of the body, as it is illustrated in Fig. 5.S2, which can explain tuning B p at ω e results in greater energy absorption than tuning at ω p . In the sea state S4, the energy is spread from about 0.4 to 1.5 rad/s (Fig. 5.S4), and the low frequency peak (ω p = 0.42 rad/s) is half of the energy frequency (ω e = 0.84 ...

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