An Assessment of PIER Electric Grid Research 2003-2014 White Paper

This white paper describes the circumstances in California around the turn of the 21st century that led the California Energy Commission (CEC) to direct additional Public Interest Energy Research funds to address critical electric grid issues, especially those arising from integrating high penetrations of variable renewable generation with the electric grid. It contains an assessment of the beneficial science and technology advances of the resultant portfolio of electric grid research projects administered under the direction of the CEC by a competitively selected contractor, the University of California’s California Institute for Energy and the Environment, from 2003-2014

Electromechanical Dynamics of High Photovoltaic Power Grids

This dissertation study focuses on the impact of high PV penetration on power grid electromechanical dynamics. Several major aspects of power grid electromechanical dynamics are studied under high PV penetration, including frequency response and control, inter-area oscillations, transient rotor angle stability and electromechanical wave propagation.To obtain dynamic models that can reasonably represent future power systems, Chapter One studies the co-optimization of generation and transmission with large-scale wind and solar. The stochastic nature of renewables is considered in the formulation of mixed-integer programming model. Chapter Two presents the development procedures of high PV model and investigates the impact of high PV penetration on frequency responses. Chapter Three studies the impact of PV penetration on inter-area oscillations of the U.S. Eastern Interconnection system. Chapter Four presents the impacts of high PV on other electromechanical dynamic issues, including transient rotor angle stability and electromechanical wave propagation. Chapter Five investigates the frequency response enhancement by conventional resources. Chapter Six explores system frequency response improvement through real power control of wind and PV. For improving situation awareness and frequency control, Chapter Seven studies disturbance location determination based on electromechanical wave propagation. In addition, a new method is developed to generate the electromechanical wave propagation speed map, which is useful to detect system inertia distribution change. Chapter Eight provides a review on power grid data architectures for monitoring and controlling power grids. Challenges and essential elements of data architecture are analyzed to identify various requirements for operating high-renewable power grids and a conceptual data architecture is proposed. Conclusions of this dissertation study are given in Chapter Nine

QUANTIFYING AND MANAGING RISK IN AGRICULTURE

Risk and Uncertainty,

Plastic circular economy in the EU: Material Flow Analysis and Transition Analysis

Plastic is valued for its versatility, but concerns have been raised over the environmental impacts of plastic waste. A more in-depth investigation of the plastic system is still needed to understand current flows and factors to close the plastic cycle. This research applied a material flow analysis (MFA) and transition analysis (TA), using multilevel perspectives, to the plastic circular economy transition in the EU. The MFA covers over 400 categories of plastic-containing products with a detailed analysis of the final destination of waste. The TA identifies the interaction of barriers and drivers to use secondary plastics, with a focus on the regime level along the plastic value chain. The MFA results indicate the EU produced over 66  million tonnes (Mt) of plastic polymers/fibres and an estimated consumption for plastic products of 73 Mt in 2016. Plastic waste increases amounted to over 37 Mt, and a significant amount of plastic waste was not recovered back into plastics in the EU. The uncertainty analysis of MFA highlights important data quality issues that need to be addressed. To understand why using secondary plastics presents challenges, the TA mapped the factors across policies and standards, markets and business models, technology, and consumer preferences and behaviours that create a web of constraints and a web of drivers. TA results highlight that data-information-knowledge is the key gap as most of the aspects are cross-cutting. Different actors are involved in new business networks and play multiple roles in driving the co-evolutionary dynamic. The thesis concludes that significant data gaps need MFA-based knowledge to inform policies that address the barriers and the potential socio-technical changes that can reshape plastic flows. The cases playing out across the whole value chain and four different application areas provide insights that are potentially more widely applicable to the circular economy transition processes in Europe

RF-MEMS switches for reconfigurable antennas

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Reconfigurable antennas are attractive for many military and commercial applications where it is required to have a single antenna that can be dynamically reconfigured to transmit or receive on multiple frequency bands and patterns. RF-MEMS is a promising technology that has the potential to revolutionize RF and microwave system implementation for next generation telecommunication applications. Despite the efforts of top industrial and academic labs, commercialization of RFMEMS switches has lagged expectations. These problems are connected with switch design (high actuation voltage, low restoring force, low power handling), packaging (contamination layers) and actuation control (high impact force, wear, fatique). This Thesis focuses on the design and control of a novel ohmic RF-MEMS switch specified for reconfigurable antennas applications. This new switch design focuses on the failure mechanisms restriction, the simplicity in fabrication, the power handling and consumption, as well as controllability. Finally, significant attention has been paid in the switch’s electromagnetic characteristics. Efficient switch control implies increased reliability. Towards this target three novel control modes are presented. 1) Optimization of a tailored pulse under Taguchi’s statistical method, which produces promising results but is also sensitive to fabrication tolerances. 2) Quantification of resistive damping control mode, which produces better results only during the pull-down phase of the switch while it is possible to be implemented successfully in very stiff devices. 3) The “Hybrid” control mode, which includes both aforementioned techniques, offering outstanding switching control, as well as immunity to fabrication tolerances, allowing an ensemble of switches rendering an antenna reconfigurable, to be used. Another issue that has been addressed throughout this work is the design and optimization of a reconfigurable, in pattern and frequency, three element Yagi-Uda antenna. The optimization of the antenna’s dimensions has been accomplished through the implementation of a novel technique based on Taguchi’s method, capable of systematically searching wider areas, named as “Grid-Taguchi” method

Meter Scoping Study

This report presents a summary of metering technology and cost information from past studies in an attempt to identify key barriers to more widespread implementation

Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included

Multi-pole permanent magnet motor design and control for high performance electromechanical actuation in all electric aircraft

The evolution of aircraft has led into a large increase in the demand for electrically integrated subsystems. Part of this demand is the transformation of a centralized hydraulic systems to independently operated electrical subsystems. The result of this overhaul will decrease aircraft weight, increase reliability, reduce aircraft lifetime maintenance and cost, and help to increase the control of power distribution. This thesis proposes the design methodology of a multi-pole permanent magnet (PM) motor with a capability to operate at high temperature. High temperature capability is one of the key requirements to implement electromechanical actuation for aircraft flight control, replace hydraulic actuation system, especially in tactical military aircraft, due to the hot environment and lack of heat sink. Temperature effects on motor materials are reviewed. The need for high power density is considered in the design. The motor design is confirm by ANYSYS RMXprt software. Along with the motor design, a voltage control method is also designed for the motor. Integrated electrical simulation results of the motor and controller to follow highly dynamic flight profiles are provided to show the stroke tracking, input power (including regenerative power), and winding copper loss. Experimentation set-up of EMA and experimental uncertainties are also discussed