177 research outputs found

    System and method for calibrating a rotary absolute position sensor

    Get PDF
    A system includes a rotary device, a rotary absolute position (RAP) sensor generating encoded pairs of voltage signals describing positional data of the rotary device, a host machine, and an algorithm. The algorithm calculates calibration parameters usable to determine an absolute position of the rotary device using the encoded pairs, and is adapted for linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters. A method of calibrating the RAP sensor includes measuring the rotary position as encoded pairs of voltage signals, linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters, and calculating an absolute position of the rotary device using the calibration parameters. The calibration parameters include a positive definite matrix (A) and a center point (q) of the ellipse. The voltage signals may include an encoded sine and cosine of a rotary angle of the rotary device

    Addressing European ocean energy challenge:The dtoceanplus structured innovation tool for concept creation and selection

    Get PDF
    The whole energy system requires renewables that scale and produce reliable, valuable energy at an acceptable cost. The key to increasing the deployment of ocean energy is bringing down development and operating costs. This paper proposes a structured approach to innovation in ocean energy systems that would spur innovation and expand the market for ocean energy. This approach can be used by a wide range of stakeholders—including technology and project developers and investors—when considering creating or improving designs. The Structured Innovation design tool within the DTOceanPlus suite is one of a kind beyond the current state-of-the-art. It enables the adaptation and integration of systematic problem-solving tools based on quality function deployment (QFD), the theory of inventive thinking (TRIZ), and the failure modes and effects analysis (FMEA) methodologies for the ocean energy sector. In obtaining and assessing innovative concepts, the integration of TRIZ into QFD enables the designers to define the innovation problem, identifies trade-offs in the system, and, with TRIZ as a systematic inventive problem-solving methodology, generates potential design concepts for the contradicting requirements. Additionally, the FMEA is used to assess the technical risks associated with the proposed design concepts. The methodology is demonstrated using high-level functional requirements for a small array of ten tidal turbines to improve the devices layout and power cabling architecture. The Structured Innovation design tool output comprises critical functional requirements with the highest overall impact and the least organisational effort to implement, along with appropriate alternative solutions to conflicting requirements

    Integrated High-Speed Torque Control System for a Robotic Joint

    Get PDF
    A control system for achieving high-speed torque for a joint of a robot includes a printed circuit board assembly (PCBA) having a collocated joint processor and high-speed communication bus. The PCBA may also include a power inverter module (PIM) and local sensor conditioning electronics (SCE) for processing sensor data from one or more motor position sensors. Torque control of a motor of the joint is provided via the PCBA as a high-speed torque loop. Each joint processor may be embedded within or collocated with the robotic joint being controlled. Collocation of the joint processor, PIM, and high-speed bus may increase noise immunity of the control system, and the localized processing of sensor data from the joint motor at the joint level may minimize bus cabling to and from each control node. The joint processor may include a field programmable gate array (FPGA)

    Method and apparatus for electromagnetically braking a motor

    Get PDF
    An electromagnetic braking system and method is provided for selectively braking a motor using an electromagnetic brake having an electromagnet, a permanent magnet, a rotor assembly, and a brake pad. The brake assembly applies when the electromagnet is de-energized and releases when the electromagnet is energized. When applied the permanent magnet moves the brake pad into frictional engagement with a housing, and when released the electromagnet cancels the flux of the permanent magnet to allow a leaf spring to move the brake pad away from the housing. A controller has a DC/DC converter for converting a main bus voltage to a lower braking voltage based on certain parameters. The converter utilizes pulse-width modulation (PWM) to regulate the braking voltage. A calibrated gap is defined between the brake pad and permanent magnet when the brake assembly is released, and may be dynamically modified via the controller

    Estimating Future Costs of Emerging Wave Energy Technologies

    Get PDF
    The development of new renewable energy technologies is generally perceived as a critical factor in the fight against climate change. However, significant difficulties arise when estimating the future performance and costs of nascent technologies such as wave energy. Robust methods to estimate the commercial costs that emerging technologies may reach in the future are needed to inform decision-making. The aim of this paper is to increase the clarity, consistency, and utility of future cost estimates for emerging wave energy technologies. It proposes a novel three-step method: (1) using a combination of existing bottom-up and top-down approaches to derive the current cost breakdown; (2) assigning uncertainty ranges, depending on the estimation reliability then used, to derive the first-of-a-kind cost of the commercial technology; and (3) applying component-based learning rates to produce the LCOE of a mature technology using the upper bound from (2) to account for optimism bias. This novel method counters the human propensity toward over-optimism. Compared with state-of-the-art direct estimation approaches, it provides a tool that can be used to explore uncertainties and focus attention on the accuracy of cost estimates and potential learning from the early stage of technology development. Moreover, this approach delivers useful information to identify remaining technology challenges, concentrate innovation efforts, and collect evidence through testing activities

    Legal and political barriers and enablers to the deployment of marine renewable energy

    Get PDF
    Ocean energy is a promising source of clean renewable energy, with clear development targets set by the European Commission. However, the ocean energy sector faces non-technological challenges and opportunities that are frequently overlooked in deployment plans. The present study aimed to provide a critical evaluation of the ocean energy sector’s legal, institutional, and political frameworks with an identification and analysis of both barriers and enabling features for the deployment of ocean energy. In the first stage, a literature review on the current political and regulatory frameworks of a set of European countries was carried out, setting the basis for the main challenges and enabling factors faced by the sector. Secondly, a critical analysis of the main non-technological barriers and enablers was performed, which was supported by questionnaires sent to regulators, technology developers, and test-site managers. This questionnaire allowed us to collect and integrate the views, perceptions, and personal experiences of the main stakeholders of the ocean energy sector in the analysis. The most relevant insights were collected to guide future policy instruments, supports, and consenting measures in a more informed and effective manner and to help accelerate the development of the sector

    Deriving Current Cost Requirements from Future Targets:Case Studies for Emerging Offshore Renewable Energy Technologies

    Get PDF
    This work investigates potential cost reduction trajectories of three emerging offshore renewable energy technologies (floating offshore wind, tidal stream, and wave) with respect to meeting ambitious cost targets set out in the Strategic Energy Technology Implementation Plans (SET-Plans) for Offshore Wind and Ocean Energy. A methodology is presented which calculates target costs for current early-stage devices, starting from the 2030 SET-Plan levelised cost targets. Component-based experience curves have been applied as part of the methodology, characterised through the comparative maturity level of each technology-specific cost centre. The resultant early-stage target costs are then compared with actual costs for current devices to highlight where further cost reduction is still required. It has been found that innovation and development requirements to reach these targets vary greatly between different technologies, based on their current level of technological maturity. Future funding calls and programmes should be designed with these variables in mind to support innovative developments in offshore renewables. The method presented in this paper has been applied to publicly available cost data for emerging renewable technologies and is fully adaptable to calculate the innovation requirements for specific early-stage renewable energy devices
    corecore