The tidal waves of modern electronic/electrical devices have led to increasing demands for ubiquitous application-specific power converters. A conventional manual design procedure of such power converters is computation- and labor-intensive, which involves selecting and connecting component devices, tuning component-wise parameters and control schemes, and iteratively evaluating and optimizing the design. To automate and speed up this design process, we propose an automatic framework that designs custom power converters from design specifications using Monte Carlo Tree Search. Specifically, the framework embraces the upper-confidence-bound-tree (UCT), a variant of Monte Carlo Tree Search, to automate topology space exploration with circuit design specification-encoded reward signals. Moreover, our UCT-based approach can exploit small offline data via the specially designed default policy and can run in parallel to accelerate topology space exploration. Further, it utilizes a hybrid circuit evaluation strategy to substantially reduce design evaluation costs. Empirically, we demonstrated that our framework could generate energy-efficient circuit topologies for various target voltage conversion ratios. Compared to existing automatic topology optimization strategies, the proposed method is much more computationally efficient—the sequential version can generate topologies with the same quality while being up to 67% faster. The parallelization schemes can further achieve high speedups compared to the sequential version.
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This content will become publicly available on June 5, 2024
Control Co-Design of Mechanical Power Takeoff for a Dual-flap Surge Wave Energy Converter
Abstract—This paper presents a control co-design method for
designing the mechanical power takeoff (PTO) system of a dual-
flap oscillating surge wave energy converter. Unlike most existing
work’s simplified representation of harvested power, this paper
derives a more realistic electrical power representation based
on a concise PTO modelling. This electrical power is used as
the objective for PTO design optimization with energy maxi-
mization control also taken into consideration to enable a more
comprehensive design evaluation. A simple PI control structure
speeds up the simultaneous co-optimization of control and PTO
parameters, and an equivalent circuit model of the WEC not
only streamlines power representation but also facilitates more
insightful evaluation of the optimization results. The optimized
PTO shows a large improvement in terms of power potential and
actual power performance. It’s found the generator’s
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- Award ID(s):
- 2152694
- NSF-PAR ID:
- 10435895
- Date Published:
- Journal Name:
- 2023 OCEANS, IEEE
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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