Share reportControl Systems
The Control Systems programme sought to design, develop and demonstrate advanced control systems for WECs and sub-systems which could deliver improvements in the WES Target Outcome Metrics.
Lead contractor
SgurrControl Ltd
Sub-contractor(s)
Cruz Atcheson Consulting Engineers Lda
Overview
The Integrated Marine Point Absorber Control Tool (IMPACT) project developed software tools to enhance and accelerate the design and implementation of advanced control systems for point absorber type wave energy converters (WECs). By doing so, the cost of designing a WEC will be reduced as control can be factored in early in the design process, informing all key / coupled subsystems such as the mechanical and electrical componentry, in opposition to a decoupled approach where control is introduced at latter stages of development.
By using a common controller design tool and software implementation, common lessons can be more readily learnt, development costs can be reduced and key performance, reliability and survivability features improved, contributing to a significant reduction in the levelised cost of energy.
The IMPACT project created a toolbox that could be used to apply a control methodology easily, allowing controllers to be designed early in the WEC development process, making the design of the WEC and the controller concurrent activities.
By producing a toolbox, point absorber developers and researchers would be able to benefit from the work as controllers would be applicable to a wide range of WECs rather than being particular to a single device. To further help the sector it was decided to make the toolbox open source and free to use.
The focus was on the development of this toolbox. Cruz Atcheson were subcontracted to use their wave energy experience to design four “exemplar” WECs to use as demonstration WECs for the toolbox and to specify the conditions for simulation testing. Controllers were then developed for each of the exemplar WECs. Using these controllers as the basis, the toolbox was then developed.
This tool simplifies and automates the process of controller design as much as possible. The controllers were tested via WECSim simulations. With the toolbox developed, it was then tested by designing a controller for a fifth WEC which was based on information provided by industrial contributors Carnegie and Trident.
The design and testing of this fifth controller was completed alongside the FEED studies for associated controller and physical test hardware.
Stage 1
July 2018
The Stage 1 Public Report for the SgurrControl "Integrated Marine Point Absorber Control Tool (IMPACT)" project includes a description of the technology, scope of work, achievements and recommendations for further work.
The IMPACT project aims to develop a control tool for point absorber Wave Energy Converters (WECs) to enable more advanced controllers than those commonly used to be designed and implemented quickly and easily. The tool aims to be as generic as possible to allow the wave energy industry as a whole to benefit.
The user is required to define their WEC and PTO (Power Take‐Off) according to a set of defined parameters. These parameters are used to construct a linearised model of the system. The user should also define the wave climate that the WEC is to be designed for. Using these inputs, IMPACT provides the user with an easy to use graphical interface for designing their controller. This includes quick and simple to use plotting of key controller performance indicators.
As IMPACT is designed to be generic, a wide range of point absorber WECs can make use of it to aid their controller design. Making controller design easier and providing a generic architecture for the controller, allows WEC and PTO developers to more easily integrate controller design into their WEC/PTO design process.
With the controller designed, IMPACT will link together with simulation software for easy implementation of the designed controllers. This includes a generic controller structure that the tool will populate, which links to the WEC‐Sim simulation package.
Stage 2
March 2019
Stage 2 of the IMPACT project focused on the development of an optimal velocity tracking (OVT) controller for point absorber WECs. Four exemplar WECs were developed, with OVT controllers then designed for each of them. A collation of all the report outputs from Stage 2 are provided in the zipped file. These outputs include reports on:
- Technical Report
- The findings of IMPACT; including the methodology for designing OVT controllers which was then formalised and a controller design tool created, a FEED study of the controller hardware, outcomes from testing the control system on a fifth WEC designed using data provided by WEC and PTO manufacturer, and the impact of the controller on the WES target outcome metrics was assessed and conclusions.
- Deliverable 4
- Detailing the controller design for single body WECs, showing the process of designing the controller, simulation test outputs, and simulation results. Additionally this report also gives background on how the controller design models and functions were developed and the theoretical background behind the work completed.
- Deliverable 6a
- A technical note on controller design for a two body WEC – detailing the model developed and the methods used for application to a surface piercing, two body WEC with a translational PTO. This deliverable builds on the work completed in deliverables 3 and 4, extending that work to enable the controller design tools previously developed to be applied to two body WECs as well as single body WECs.
- Deliverable 6b
- A technical note on controller design for a two body WEC – detailing the models developed and the methods used for application to a sub-surface, two-body WEC with a translational PTO. This deliverable builds on the work completed in deliverables 3 and 4, extending that work to enable the controller design tools previously developed to be applied to two body WECs as well as single body WECs.
Impact Tool
The attached zipped file gives access to the toolbox developed in Stage 2 of the IMPACT control project. The contents include:
- Control Design, Data Analyser Manuals, and Installation Guide
- A zip file including the Control Design Manual, Data Analyser Manual, and Installation Guide.
- Toolbox and Source Code
- A zip file containing the Toolbox and Source code required to run the tool.
Please be aware this total zip file size is over 30MB, and it is recommended to download to a laptop or desktop.
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