Design and Development of Advanced Control strategies for Power Quality Enhancement at Distribution Level

In recent times, power quality (PQ) issues such as current and voltage harmonics, voltage sag/swell, voltage unbalances have become the important causes for malfunctioning and degradation of the quality of power. Poor power quality severely affects on electrical equipment and finally results in significant economic losses. Hence, installation of the custom power devices to improve the power quality issues becomes an important consideration. Therefore, this thesis considers the enhancement of power quality for power distribution systems by utilizing unified power quality conditioner (UPQC). An UPQC can adequately handle several power quality problems such as load current harmonics, supply voltage distortions, voltage sags/swells and voltage unbalance. Therefore, the main focus behind this thesis is to develop advanced control strategies that improve the compensation capability of the UPQC so that power quality issues of distribution network are efficiently improved. Firstly, the current harmonics are considered and are compensated by using the shunt active power filter (SAPF). Therefore, two control strategies such as Hysteresis current control (HCC) and Sliding Mode Control (SMC) based control algorithms are implemented to compensate current harmonics in the power distribution network. Furthermore, both the current control techniques utilize the Coulon oscillator based PLL (CO-PLL) for extraction of positive sequence signal from the supply voltage and generate the three-phase reference currents by employing PI-controller based DC-link voltage regulation. The performances of both current control techniques for SAPF are evaluated under different source voltage conditions such as balanced, unbalanced and non-sinusoidal. The SAPF effectively compensates currents harmonic, however, it is unable to compensate voltage related problems. To overcome this drawback, this thesis considers the UPQC, which comprises with shunt APF and series APF, can be utilized to compensate both current and voltage related problems. The research on UPQC is carried out progressively by considering different advanced control strategies. Each progress in the research enhances the compensation capabilities of the previous UPQC control system. The simulation and realtime Opal-RT studies are carried out to verify the operating performance of each design concept of UPQC. At first, operating principle and design of UPQC is presented and then a novel control algorithm is introduced with the aid of nonlinear DC-link voltage controller such as nonlinear variable gain fuzzy (NVGF) controller and nonlinear sliding mode controller (NLSMC) with modified synchronous reference frame (SRF) control strategy for improvement of both current and voltage compensation performance of the UPQC. However, existence of large settling time in dc voltage leads to poor dynamic performance of NVGF control technique and hence current harmonics, voltage distortions and voltage disturbance such as voltage sag/swell as well as voltage unbalance compensation capability of this technique is not quite effective in comparison to the NLSMC technique. Moreover, NLSMC is very sensitive to model mismatch and noise. It is quite sluggish in rejecting long drifting grid disturbances. Hence, a suitable control strategy has to be developed in UPQC, which has improved DC-link voltage regulation as well as tracking performance through load and grid perturbations. To overcome this drawback a resistive optimization technique (ROT) incorporated with enhanced phase-locked loop (EPLL) based NVGF hysteresis control strategy and an optimum active power (OAP) technique combined with enhanced phase-locked loop (EPLL) based fuzzy sliding mode (FSM) pulse-width modulation (PWM) control strategy for UPQC have been discussed. ROT-NVGF and OAP-FSMC based UPQC control strategies are adaptive as well as robust and able to mitigate the PQ problems satisfactorily during all dynamic conditions of power system perturbation. However, performances of these controllers are not effective when there is a variation occurring either in the nonlinear load parameter or supply voltage parameter. Thus, UPQC may not be able to compensate PQ problems satisfactorily. Considering aforesaid problems, this thesis proposes a command generator tracker (CGT) based direct adaptive control (DAC) applied to a three-phase three-wire UPQC to improve the current and voltage harmonics, sag/swell and voltage unbalance in the power system distribution network. CGT is a model reference control law for a linear timeinvariant system with known coefficients and is formulated for the generation of reference signal for both shunt and series inverter. The main advantage of the proposed control algorithm is that no online extraction is needed to perceive the UPQC parameters. Moreover, IV the adaptive control law is designed to track a linear reference model to reduce the tracking error between model reference output and measured signal to be controlled. Additionally, this proposed algorithm adaptively regulates the DC-link capacitor voltage without utilizing additional controller circuit. As a result, the proposed algorithm provides more robustness, flexibility and adaptability in all operating conditions of the power system network. At last, model reference robust adaptive control (MRRAC) technique is proposed for single phase UPQC system. This control strategy is designed with the purpose of achieving high stability, high disturbance rejection and high level of harmonics cancellation. From simulation results, it is not only found to be robust against PI-controller, but also satisfactory THD results have been achieved in UPQC system. This has motivated to develop a prototype experimental set up in the Laboratory using FPGA (Field Programmable Gate Array) based NI (National Instruments) cRIO-9014. From both the simulation and experimentation, it is observed that the proposed MRRAC approach to design a UPQC system is found to be more effective as compared to the conventional PI-controller

Control Analysis for Grid Tied Battery Energy Storage System for SOC and SOH Management

Frequency regulation is an important part of grid ancillary services in the UK power system to mitigate the impacts of variable energy resources and uncertainty of load on system frequency. The National Grid Electricity Transmission (NGET), the primary electricity transmission network operator in the UK, is introduced various frequency response services such as firm frequency response (FFR) and the new fast enhanced frequency response (EFR), which are designed to provide real-time response to deviations in the grid frequency. Flexible and fast response capabilities of battery energy storage systems (BESSs) make them an ideal choice to provide grid frequency regulation. This thesis presents control algorithms for a BESS to deliver a charge/discharge power output in response to deviations in the grid frequency with respect to the requisite service specifications, while managing the state-of-charge (SOC) of the BESS to optimize the availability of the system. Furthermore, this thesis investigates using the BESS in order to maximize triad avoidance benefit revenues while layering UK grid frequency response services. Using historical UK electricity prices, a balancing service scheduling approach is introduced to maximize energy arbitrage revenue by layering different types of grid balancing services, including EFR and FFR, throughout the day. Simulation results demonstrate that the proposed algorithm delivers both dynamic and non-dynamic FFR and also EFR to NGET required service specifications while generating arbitrage revenue as well as service availability payments in the balancing market. In this thesis, a new fast cycle counting method (CCM) considering the effect of current rate (C-rate), SOC and depth-of-discharge (DOD) on battery lifetime for grid-tied BESS is presented. The methodology provides an approximation for the number of battery charge-discharge cycles based on historical microcyling SOC data typical of BESS frequency regulation operation. The EFR and FFR algorithms are used for analysis. The obtained historical SOC data from the analysis are then considered as an input for evaluating the proposed CCM. Utilizing the Miner Rule’s degradation analysis method, lifetime analysis based on battery cycling is also provided for a lithium-titanate (LTO) and lithium-nickel-manganese-cobalt-oxide (NMC) battery. The work in this thesis is supported by experimental results from the 2MW/1MWh Willenhall Energy Storage System (WESS) to validate the models and assess the accuracy of the simulation results

Wooden Musical Instruments - Different Forms of Knowledge: Book of End of WoodMusICK COST Action FP1302

International audienceMusical instrument are fundamental tools of human expression that reveal and reflect historical, technological, social and cultural aspects of times and people. These three-dimensional, polyma-teric objects-at times considered artworks, other times technical objects-are the most powerful way to communicate emotions and to connect people and communities with the surrounding world. The participants in WoodMusICK (WOODen MUSical Instrument Conservation and Knowledge) COST Action FP1302 have aimed to combine forces and to foster research on wooden musical instruments in order to preserve, develop and disseminate knowledge on musical instruments in Europe through inter-and transdisciplinary research. This four-year program, supported by COST (European Cooperation in Science and Technology), has involved a multidisciplinary and multinational research group composed of curators, conservators/restorers, wood, material and mechanical scientists, chemists, acousticians, organologists and instrument makers. The goal of the COST Action was to improve the knowledge and preservation of wooden musical instruments heritage by increasing the interaction and synergy between different disciplines

Sustainability in design: now! Challenges and opportunities for design research, education and practice in the XXI century

Copyright @ 2010 Greenleaf PublicationsLeNS project funded by the Asia Link Programme, EuropeAid, European Commission

Pilot\u27s Handbook of Aeronautical Knowledge, 2016

The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge that is essential for pilots. This handbook introduces pilots to the broad spectrum of knowledge that will be needed as they progress in their pilot training. Except for the Code of Federal Regulations pertinent to civil aviation, most of the knowledge areas applicable to pilot certification are presented. The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge for the student pilot learning to fly, as well as pilots seeking advanced pilot certification. For detailed information on a variety of specialized flight topics, see specific Federal Aviation Administration (FAA) handbooks and Advisory Circulars (ACs). Occasionally the word “must” or similar language is used where the desired action is deemed critical. The use of such language is not intended to add to, interpret, or relieve a duty imposed by Title 14 of the Code of Federal Regulations (14 CFR). It is essential for persons using this handbook to become familiar with and apply the pertinent parts of 14 CFR and the Aeronautical Information Manual (AIM). The AIM is available online at www.faa.gov. The current Flight Standards Service airman training and testing material and learning statements for all airman certificates and ratings can be obtained from https://www.faa.gov

Pilot\u27s Handbook of Aeronautical Knowledge, 2016

The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge that is essential for pilots. This handbook introduces pilots to the broad spectrum of knowledge that will be needed as they progress in their pilot training. Except for the Code of Federal Regulations pertinent to civil aviation, most of the knowledge areas applicable to pilot certification are presented. The Pilot’s Handbook of Aeronautical Knowledge provides basic knowledge for the student pilot learning to fly, as well as pilots seeking advanced pilot certification. For detailed information on a variety of specialized flight topics, see specific Federal Aviation Administration (FAA) handbooks and Advisory Circulars (ACs). Occasionally the word “must” or similar language is used where the desired action is deemed critical. The use of such language is not intended to add to, interpret, or relieve a duty imposed by Title 14 of the Code of Federal Regulations (14 CFR). It is essential for persons using this handbook to become familiar with and apply the pertinent parts of 14 CFR and the Aeronautical Information Manual (AIM). The AIM is available online at www.faa.gov. The current Flight Standards Service airman training and testing material and learning statements for all airman certificates and ratings can be obtained from https://www.faa.gov

The PEEC Experiment: Native Hawaiian and Native American Engineering Education

PART I: Context 1. Engineering for Native nations: Origins and goals of the Pre-Engineering Education Collaboratives (PEECs)PART II: Culture matters 2. Recognizing history: Indigeneity matters 3. Moving beyond cultural sensitivity: Developing culturally responsive programs for and with Native engineers 4. Invoking cultural relevance at tribal colleges: Grandmother’s way is important5. Discovering what works: STEM pedagogy and curriculum development for Native Americans6. Exploring indigenous science and engineering: Projects with indigenous rootsPART III: Providing support for Natives in Engineering7. Finding an Engineering identity: A Native American PEEC leader’s experience8. Outreaching to K-12 and tribal schools in PEEC9. Establishing who leads: Hawaiian-serving community colleges or tribal colleges as leaders10. Discovering how and how well Native-Hawaiian community colleges work with a mainstream university in Hawai‘i11. Assembling interconnected networks for advancement in engineering: Champions and community12. Increasing enrollment and graduation through teaching and learning strategies: Experiential learningPART IV: Transforming institutional politics13. Transforming through institutionalization and replicability of PEEC14. Obtaining permission to work on reservations: About IRB/RRB regulations15. Involving STEM teachers with tribal faculty in PEEC: Joining forces to serve undergraduatesPART V: Learning from experience16. Joining forces with unexpected PEEC-enhancing projects along the way: Unforeseen alliances in South Dakota 17. Promoting Native women: An underutilized resource 18. Succeeding with students: PEEC student stories19. Measuring outcomes20. Implementing through low-cost solutions21. Useful references22. Contributors23. Epiloguehttps://openprairie.sdstate.edu/cvlee_book/1000/thumbnail.jp