This paper discusses wave-by-wave near-optimal
control of a wave energy device in irregular waves. A deterministic
propagation model is used to predict the wave elevation several
seconds into the future at the device location. Two prediction
approaches are considered. The first is based on a time series
being measured over an advancing time window at a particular
up-wave location. This approach is here utilized in long-crested
irregular waves. The second approach uses successive snapshots
of wave elevation measurements over an up-wave area.
This approach is found more convenient for multi-directional
waves, and is here applied in a bi-directional wave irregular
wave field. A small, heaving vertical cylinder reacting against a
deeply submerged (i.e. assumed to undergo negligible oscillations)
mass is studied under wave-by-wave control. The non-causal
feedforward control force required for optimum velocity under
a swept-volume constraint is based on the past, current, and
predicted wave elevation at the device. Results for time-averaged
converted power and displacement/force maxima are obtained for
a range of irregular wave conditions. Also presented in addition
are energy conversion results with a feedback-alone control force
using a multi-resonant control technique.
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A layout optimization method based on wave wake preprocessing concept for wave-wind hybrid energy farms
- Award ID(s):
- 1757812
- NSF-PAR ID:
- 10317737
- Date Published:
- Journal Name:
- Energy Conversion and Management
- Volume:
- 244
- Issue:
- C
- ISSN:
- 0196-8904
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.enconman.2021.114469
