Evaluation of quadrature signal generation methods with reduced computational resources for grid synchronization of single-phase power converters through phase-locked loops

Low-cost single-phase grid connected converters require synchronization with the grid voltage to obtain a better response and protection under diverse conditions, such as frequency perturbations and distortion. Phase-locked loops (PLLs) have been used in this scenario. This paper describes a set of quadrature signal generators for single-phase PLLs; compares the performances by means of simulation tests considering diverse operation conditions of the electrical grid; proposes strategies to reduce the computational burden, considering fixed-point digital implementations; and provides both descriptive and quantitative comparisons of the required mathematical operations and memory units for implementation of the analyzed single-phase PLLs.This work has been supported by the Spanish Ministry of Science and Innovation under Project RTI2018-095138-B-C31 PEGIA—Power Electronics for the Grid and Industry Applications

Design and Implementation of FPGA based linear All Digital Phase-Locked Loop for Signal Processing Applications

This project presents a linear all-digital phase locked loop based on FPGA. In this ADPLL the phase detection system is realized by generating an analytic signal using a compact implementation of Hilbert transform and then simply computing the instantaneous phase using CORDIC algorithm in vectoring mode of operation. A 16-bit pipelined CORDIC algorithm is employed in order to obtain the phase information of the signal. All the components used in this phase detection system are realized as digital discrete time components. This design does not involve any class of multipliers thus reducing the complexity of the design. The loop filter of the ADPLL has been designed using PI controller which has a low pass behavior and is used to discard the higher order harmonics of the error signal. The CORDIC algorithm in its rotation mode of operation is used to compute sinusoidal values for the DDS. The ADPLL model has been implemented using Xilinx ISE 12.3 and ModelSim PE Student Edition 10.1a. The ADPLL model describes a novel method of implementation of CORDIC algorithm for the DDS system. This ADPLL model basically used for synchronization of closed loop RF control signals in a heavy ion particle accelerator can be implemented even in an ASIC which can be seen with a more general use for many a applications in the daily life

Implementation of digital signal processing algorithms in biomedical electronics devices on the Xilinx FPGA

В современных инженерных задачах процесс создания полностью цифровых биомедицинских диагностических устройств предполагает глубокие знания как в цифровой электронике, так и в цифровой обработке биомедицинских сигналов [1-3]. Целью данной работы является разработка инженерного подхода аппаратной (жесткой логики) реализации базовых алгоритмов цифровой обработки сигналов (ЦОС) используемых в биомедицинских электронных устройствах на основе программируемых логических интегральных схем. Процесс аппаратной реализации базовых алгоритмов цифровой обработки сигналов можно разделить на три основных этапа. На первом этапе проводится вычисление амплитудных значений отсчетов дискретных импульсных характеристик фильтра нижних частот и фильтра Гильберта в приложении FDATool среды Matlab. На следующем этапе в приложении Simulink выполняется имитационное моделирование (симуляция) на основе результатов первого этапа, и на этапе аппаратной реализации на программируемой логической интегральной схеме Xilinx серии Spartan 6 проводится как симуляция цепей ЦОС в системе проектирования Xilinx ISE, так и непосредственно экспериментальные измерения. В качестве примера натурной реализации базовых алгоритмов ЦОС в биомедицинских устройствах был выбран демодулятор амплитудно-модулированных колебаний. Экспериментальным путем были проведены измерения коэффициента нелинейных искажений продетектированного (информационного) сигнала для трех вариантов АМ демодуляторов: двухполупериодный, с применением функции квадратного корня и синхронного с фазовой автоподстройкой частоты. В ходе экспериментального исследования был выбран оптимальный с точки зрения энергетической эффективности коэффициент модуляции равный 60 %. Как показывают и результаты имитационного моделирования и экспериментального исследования наилучшим вариантом оказался синхронный демодулятор. Полученные результаты эксперимента и моделирования подтвердили практическую применимость предложенного варианта реализации в ЦОС для использования их в биомедицинских электронных устройствах.The process of creating fully digital biomedical diagnostic devices involves deep knowledge in both digital electronics and digital biomedical signals processing [1-3]. The purpose of this paper is development of the engineering approach of hardware implementation of basic digital signal processing algorithms (DSP) applied in biomedical electronic devices based on programmable logic integrated circuits. The processes of hardware implementation of the basic algorithms for digital signal processing (DSP) can be divided into three main steps. At the first step, the amplitude values of the samples of discrete pulse characteristics of the low-pass filter and the Hilbert filter are calculated in the FDATool application of the Matlab. At the next step, the Simulink application performs simulation modeling based on the results of the first step, and at the hardware implementation step, the field programmable gate array Xilinx Spartan 6 is used to simulate DSP circuits in the Xilinx ISE design system, as well as directly measured measurements. The amplitude-modulated oscillations demodulator was chosen as an example of the full-scale implementation of basic DSP algorithms in biomedical devices. Experimental measurements were made of the nonlinear distortion coefficient of the detected (informational) signal for three variants of amplitude modulation demodulators: full-wave, using the square root function and synchronous with phase locked loop. During the experimental study, an optimal modulation factor of 60% was chosen from the point of view of energy efficiency. As the results of simulation and experimental studies show, the synchronous demodulat or has turned out to be the best option.The obtained results of the experiment and simulation have confirmed the practical applicability of the proposed embodiment in DSP for use in biomedical electronic devices

An Efficient FPGA Implementation of a Quadrature Signal-Generation Subsystem in SRF PLLs in Single-Phase PFCs

Synchronization with the utility voltage is naturally carried out by a diode bridge stage in single-phase active rectifiers, while an active synchronization is included in the control algorithms applied to modern bridgeless topologies. Sensorless line current rebuilding algorithms also need synchronization with the line voltage to compensate at least for part of the current estimation error. The phase-locked-loop (PLL) circuits employed in single-phase ac-dc converters are reviewed and a new digital PLL algorithm, based on the synchronous reference frame, is proposed. It is implemented in a field-programmable gate array to utilize the parallelism and superior time resolution. Considering a restricted frequency variation of the line voltage around the central frequency, the orthogonal signal is obtained by a discrete differential operator designed to ensure unity gain at the central frequency. Its performance, including the memory and computational cost, versus previously consolidated algorithms implemented in the same device is analyzed. Simulations and experimental results prove its suitable behavior in steady state at different line frequencies and under line voltage and frequency transients

Detection of faults in a scaled down doubly-fed induction generator using advanced signal processing techniques.

The study ventures into the development of a micro-based doubly fed induction generator (DFIG) test rig for fault studies. The 5kW wound rotor induction machine (WRIM) that was used in the test rig was based on a scaled-down version of a 2.5MW doubly fed induction generator (DFIG). The micromachine has been customized to make provision for implementing stator inter-turn short-circuit faults (ITSCF), rotor ITSCF and static eccentricity (SE) faults in the laboratory environment. The micromachine has been assessed under the healthy and faulty states, both before and after incorporating a converter into the rotor circuit of the machine. In each scenario, the fault signatures have been characterised by analyzing the stator current, rotor current, and the DFIG controller signals using the motor current signature analysis (MCSA) and discrete wavelet transform (DWT) analysis techniques to detect the dominant frequency components which are indicative of these faults. The purpose of the study is to evaluate and identify the most suitable combination of signals and techniques for the detection of each fault under steady-state and transient operating conditions. The analyses of the results presented in this study have indicated that characterizing the fault indicators independent of the converter system ensured clarity in the fault diagnosis process and enabled the development of a systematic fault diagnosis approach that can be applied to a controlled DFIG. It has been demonstrated that the occurrence of the ITSCFs and the SE fault in the micro-WRIM intensifies specific frequency components in the spectral plots of the stator current, rotor current, and the DFIG controller signals, which may then serve as the dominant fault indicators. These dominant components may be used as fault markers for classification and have been used for pattern recognition under the transient condition. In this case, the DWT and spectrogram plots effectively illustrated characteristic patterns of the dominant fault indicators, which were observed to evolve uniquely and more distinguishable in the rotor current signal compared to the stator current signal, before incorporating the converter in the rotor circuit. Therefore, by observing the trends portrayed in the decomposition bands and the spectrogram plots, it is deemed a reliable method of diagnosing and possibly quantifying the intensity of the faults in the machine. Once the power electronic converter was incorporated into the rotor circuit, the DFIG controller signals have been observed to be best suited for diagnosing faults in the micro-DFIG under the steady-state operating condition, as opposed to using the terminal stator or rotor current signals. The study also assessed the impact of undervoltage conditions at the point of common coupling (PCC) on the behaviour of the micro-DFIG. In this investigation, a significant rise in the faulted currents was observed for the undervoltage condition in comparison to the faulty cases under the rated grid voltage conditions. In this regard, it could be detrimental to the operation of the micro-DFIG, particularly the faulted phase windings, and the power electronic converter, should the currents exceed the rated values for extended periods

Principles, fundamentals, and applications of programmable integrated photonics

[EN] Programmable integrated photonics is an emerging new paradigm that aims at designing common integrated optical hardware resource configurations, capable of implementing an unconstrained variety of functionalities by suitable programming, following a parallel but not identical path to that of integrated electronics in the past two decades of the last century. Programmable integrated photonics is raising considerable interest, as it is driven by the surge of a considerable number of new applications in the fields of telecommunications, quantum information processing, sensing, and neurophotonics, calling for flexible, reconfigurable, low-cost, compact, and low-power-consuming devices that can cooperate with integrated electronic devices to overcome the limitation expected by the demise of Moore¿s Law. Integrated photonic devices exploiting full programmability are expected to scale from application-specific photonic chips (featuring a relatively low number of functionalities) up to very complex application-agnostic complex subsystems much in the same way as field programmable gate arrays and microprocessors operate in electronics. Two main differences need to be considered. First, as opposed to integrated electronics, programmable integrated photonics will carry analog operations over the signals to be processed. Second, the scale of integration density will be several orders of magnitude smaller due to the physical limitations imposed by the wavelength ratio of electrons and light wave photons. The success of programmable integrated photonics will depend on leveraging the properties of integrated photonic devices and, in particular, on research into suitable interconnection hardware architectures that can offer a very high spatial regularity as well as the possibility of independently setting (with a very low power consumption) the interconnection state of each connecting element. Integrated multiport interferometers and waveguide meshes provide regular and periodic geometries, formed by replicating unit elements and cells, respectively. In the case of waveguide meshes, the cells can take the form of a square, hexagon, or triangle, among other configurations. Each side of the cell is formed by two integrated waveguides connected by means of a Mach¿Zehnder interferometer or a tunable directional coupler that can be operated by means of an output control signal as a crossbar switch or as a variable coupler with independent power division ratio and phase shift. In this paper, we provide the basic foundations and principles behind the construction of these complex programmable circuits. We also review some practical aspects that limit the programming and scalability of programmable integrated photonics and provide an overview of some of the most salient applications demonstrated so far.European Research Council; Conselleria d'Educació, Investigació, Cultura i Esport; Ministerio de Ciencia, Innovación y Universidades; European Cooperation in Science and Technology; Horizon 2020 Framework Programme.Pérez-López, D.; Gasulla Mestre, I.; Dasmahapatra, P.; Capmany Francoy, J. (2020). Principles, fundamentals, and applications of programmable integrated photonics. Advances in Optics and Photonics. 12(3):709-786. https://doi.org/10.1364/AOP.387155709786123Lyke, J. C., Christodoulou, C. G., Vera, G. A., & Edwards, A. H. (2015). An Introduction to Reconfigurable Systems. Proceedings of the IEEE, 103(3), 291-317. doi:10.1109/jproc.2015.2397832Kaeslin, H. (2008). Digital Integrated Circuit Design. doi:10.1017/cbo9780511805172Trimberger, S. M. (2015). Three Ages of FPGAs: A Retrospective on the First Thirty Years of FPGA Technology. Proceedings of the IEEE, 103(3), 318-331. doi:10.1109/jproc.2015.2392104Mitola, J. (1995). The software radio architecture. IEEE Communications Magazine, 33(5), 26-38. doi:10.1109/35.393001Nunes, B. A. A., Mendonca, M., Nguyen, X.-N., Obraczka, K., & Turletti, T. (2014). A Survey of Software-Defined Networking: Past, Present, and Future of Programmable Networks. IEEE Communications Surveys & Tutorials, 16(3), 1617-1634. doi:10.1109/surv.2014.012214.00180Papagianni, C., Leivadeas, A., Papavassiliou, S., Maglaris, V., Cervello-Pastor, C., & Monje, A. (2013). On the optimal allocation of virtual resources in cloud computing networks. IEEE Transactions on Computers, 62(6), 1060-1071. doi:10.1109/tc.2013.31Peruzzo, A., Laing, A., Politi, A., Rudolph, T., & O’Brien, J. L. (2011). Multimode quantum interference of photons in multiport integrated devices. Nature Communications, 2(1). doi:10.1038/ncomms1228Metcalf, B. J., Thomas-Peter, N., Spring, J. B., Kundys, D., Broome, M. A., Humphreys, P. C., … Walmsley, I. A. (2013). Multiphoton quantum interference in a multiport integrated photonic device. Nature Communications, 4(1). doi:10.1038/ncomms2349Miller, D. A. B. (2013). Self-aligning universal beam coupler. Optics Express, 21(5), 6360. doi:10.1364/oe.21.006360Miller, D. A. B. (2013). Self-configuring universal linear optical component [Invited]. Photonics Research, 1(1), 1. doi:10.1364/prj.1.000001Carolan, J., Harrold, C., Sparrow, C., Martín-López, E., Russell, N. J., Silverstone, J. W., … Laing, A. (2015). Universal linear optics. Science, 349(6249), 711-716. doi:10.1126/science.aab3642Harris, N. C., Steinbrecher, G. R., Prabhu, M., Lahini, Y., Mower, J., Bunandar, D., … Englund, D. (2017). Quantum transport simulations in a programmable nanophotonic processor. Nature Photonics, 11(7), 447-452. doi:10.1038/nphoton.2017.95Birth of the programmable optical chip. (2015). Nature Photonics, 10(1), 1-1. doi:10.1038/nphoton.2015.265Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K.-J., & Lowery, A. J. (2015). Programmable photonic signal processor chip for radiofrequency applications. Optica, 2(10), 854. doi:10.1364/optica.2.000854Pérez, D., Gasulla, I., Capmany, J., & Soref, R. A. (2016). Reconfigurable lattice mesh designs for programmable photonic processors. Optics Express, 24(11), 12093. doi:10.1364/oe.24.012093Capmany, J., Gasulla, I., & Pérez, D. (2015). The programmable processor. Nature Photonics, 10(1), 6-8. doi:10.1038/nphoton.2015.254Pérez, D., Gasulla, I., Crudgington, L., Thomson, D. J., Khokhar, A. Z., Li, K., … Capmany, J. (2017). Multipurpose silicon photonics signal processor core. Nature Communications, 8(1). doi:10.1038/s41467-017-00714-1Clements, W. R., Humphreys, P. C., Metcalf, B. J., Kolthammer, W. S., & Walsmley, I. A. (2016). Optimal design for universal multiport interferometers. Optica, 3(12), 1460. doi:10.1364/optica.3.001460Perez, D., Gasulla, I., Fraile, F. J., Crudgington, L., Thomson, D. J., Khokhar, A. Z., … Capmany, J. (2017). Silicon Photonics Rectangular Universal Interferometer. Laser & Photonics Reviews, 11(6), 1700219. doi:10.1002/lpor.201700219Shen, Y., Harris, N. C., Skirlo, S., Prabhu, M., Baehr-Jones, T., Hochberg, M., … Soljačić, M. (2017). Deep learning with coherent nanophotonic circuits. Nature Photonics, 11(7), 441-446. doi:10.1038/nphoton.2017.93Ribeiro, A., Ruocco, A., Vanacker, L., & Bogaerts, W. (2016). Demonstration of a 4 × 4-port universal linear circuit. Optica, 3(12), 1348. doi:10.1364/optica.3.001348Annoni, A., Guglielmi, E., Carminati, M., Ferrari, G., Sampietro, M., Miller, D. A., … Morichetti, F. (2017). Unscrambling light—automatically undoing strong mixing between modes. Light: Science & Applications, 6(12), e17110-e17110. doi:10.1038/lsa.2017.110Perez, D., Gasulla, I., & Capmany, J. (2018). Toward Programmable Microwave Photonics Processors. Journal of Lightwave Technology, 36(2), 519-532. doi:10.1109/jlt.2017.2778741Chen, L., Hall, E., Theogarajan, L., & Bowers, J. (2011). Photonic Switching for Data Center Applications. IEEE Photonics Journal, 3(5), 834-844. doi:10.1109/jphot.2011.2166994Miller, D. A. B. (2017). Meshing optics with applications. Nature Photonics, 11(7), 403-404. doi:10.1038/nphoton.2017.104Thomas-Peter, N., Langford, N. K., Datta, A., Zhang, L., Smith, B. J., Spring, J. B., … Walmsley, I. A. (2011). Integrated photonic sensing. New Journal of Physics, 13(5), 055024. doi:10.1088/1367-2630/13/5/055024Smit, M., Leijtens, X., Ambrosius, H., Bente, E., van der Tol, J., Smalbrugge, B., … van Veldhoven, R. (2014). An introduction to InP-based generic integration technology. Semiconductor Science and Technology, 29(8), 083001. doi:10.1088/0268-1242/29/8/083001Coldren, L. A., Nicholes, S. C., Johansson, L., Ristic, S., Guzzon, R. S., Norberg, E. J., & Krishnamachari, U. (2011). High Performance InP-Based Photonic ICs—A Tutorial. Journal of Lightwave Technology, 29(4), 554-570. doi:10.1109/jlt.2010.2100807Kish, F., Nagarajan, R., Welch, D., Evans, P., Rossi, J., Pleumeekers, J., … Joyner, C. (2013). From Visible Light-Emitting Diodes to Large-Scale III–V Photonic Integrated Circuits. Proceedings of the IEEE, 101(10), 2255-2270. doi:10.1109/jproc.2013.2275018Hochberg, M., & Baehr-Jones, T. (2010). Towards fabless silicon photonics. Nature Photonics, 4(8), 492-494. doi:10.1038/nphoton.2010.172Bogaerts, W., Fiers, M., & Dumon, P. (2014). Design Challenges in Silicon Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 20(4), 1-8. doi:10.1109/jstqe.2013.2295882Soref, R. (2006). The Past, Present, and Future of Silicon Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 12(6), 1678-1687. doi:10.1109/jstqe.2006.883151Chrostowski, L., & Hochberg, M. (2015). Silicon Photonics Design. doi:10.1017/cbo9781316084168Heck, M. J. R., Bauters, J. F., Davenport, M. L., Doylend, J. K., Jain, S., Kurczveil, G., … Bowers, J. E. (2013). Hybrid Silicon Photonic Integrated Circuit Technology. IEEE Journal of Selected Topics in Quantum Electronics, 19(4), 6100117-6100117. doi:10.1109/jstqe.2012.2235413Keyvaninia, S., Muneeb, M., Stanković, S., Van Veldhoven, P. J., Van Thourhout, D., & Roelkens, G. (2012). Ultra-thin DVS-BCB adhesive bonding of III-V wafers, dies and multiple dies to a patterned silicon-on-insulator substrate. Optical Materials Express, 3(1), 35. doi:10.1364/ome.3.000035Heideman, R., Hoekman, M., & Schreuder, E. (2012). TriPleX-Based Integrated Optical Ring Resonators for Lab-on-a-Chip and Environmental Detection. IEEE Journal of Selected Topics in Quantum Electronics, 18(5), 1583-1596. doi:10.1109/jstqe.2012.2188382Roeloffzen, C. G. H., Zhuang, L., Taddei, C., Leinse, A., Heideman, R. G., van Dijk, P. W. L., … Boller, K.-J. (2013). Silicon nitride microwave photonic circuits. Optics Express, 21(19), 22937. doi:10.1364/oe.21.022937Corbett, B., Loi, R., Zhou, W., Liu, D., & Ma, Z. (2017). Transfer print techniques for heterogeneous integration of photonic components. Progress in Quantum Electronics, 52, 1-17. doi:10.1016/j.pquantelec.2017.01.001Van der Tol, J. J. G. M., Jiao, Y., Shen, L., Millan-Mejia, A., Pogoretskii, V., van Engelen, J. P., & Smit, M. K. (2018). Indium Phosphide Integrated Photonics in Membranes. IEEE Journal of Selected Topics in Quantum Electronics, 24(1), 1-9. doi:10.1109/jstqe.2017.2772786Bachmann, M., Besse, P. A., & Melchior, H. (1994). General self-imaging properties in N × N multimode interference couplers including phase relations. Applied Optics, 33(18), 3905. doi:10.1364/ao.33.003905Soldano, L. B., & Pennings, E. C. M. (1995). Optical multi-mode interference devices based on self-imaging: principles and applications. Journal of Lightwave Technology, 13(4), 615-627. doi:10.1109/50.372474Madsen, C. K., & Zhao, J. H. (1999). Optical Filter Design and Analysis. Wiley Series in Microwave and Optical Engineering. doi:10.1002/0471213756Desurvire, E. (2009). Classical and Quantum Information Theory. doi:10.1017/cbo9780511803758Knill, E., Laflamme, R., & Milburn, G. J. (2001). A scheme for efficient quantum computation with linear optics. Nature, 409(6816), 46-52. doi:10.1038/35051009Capmany, J., & Pérez, D. (2020). Programmable Integrated Photonics. doi:10.1093/oso/9780198844402.001.0001Spagnolo, N., Vitelli, C., Bentivegna, M., Brod, D. J., Crespi, A., Flamini, F., … Sciarrino, F. (2014). Experimental validation of photonic boson sampling. Nature Photonics, 8(8), 615-620. doi:10.1038/nphoton.2014.135Mennea, P. L., Clements, W. R., Smith, D. H., Gates, J. C., Metcalf, B. J., Bannerman, R. H. S., … Smith, P. G. R. (2018). Modular linear optical circuits. Optica, 5(9), 1087. doi:10.1364/optica.5.001087Perez-Lopez, D., Sanchez, E., & Capmany, J. (2018). Programmable True Time Delay Lines Using Integrated Waveguide Meshes. Journal of Lightwave Technology, 36(19), 4591-4601. doi:10.1109/jlt.2018.2831008Pérez-López, D., Gutierrez, A. M., Sánchez, E., DasMahapatra, P., & Capmany, J. (2019). Integrated photonic tunable basic units using dual-drive directional couplers. Optics Express, 27(26), 38071. doi:10.1364/oe.27.038071Jinguji, K., & Kawachi, M. (1995). Synthesis of coherent two-port lattice-form optical delay-line circuit. Journal of Lightwave Technology, 13(1), 73-82. doi:10.1109/50.350643Mookherjea, S., & Yariv, A. (2002). Coupled resonator optical waveguides. IEEE Journal of Selected Topics in Quantum Electronics, 8(3), 448-456. doi:10.1109/jstqe.2002.1016347Heebner, J. E., Chak, P., Pereira, S., Sipe, J. E., & Boyd, R. W. (2004). Distributed and localized feedback in microresonator sequences for linear and nonlinear optics. Journal of the Optical Society of America B, 21(10), 1818. doi:10.1364/josab.21.001818Fandiño, J. S., Muñoz, P., Doménech, D., & Capmany, J. (2016). A monolithic integrated photonic microwave filter. Nature Photonics, 11(2), 124-129. doi:10.1038/nphoton.2016.233Miller, D. A. B. (2012). All linear optical devices are mode converters. Optics Express, 20(21), 23985. doi:10.1364/oe.20.023985Brown, S. D., Francis, R. J., Rose, J., & Vranesic, Z. G. (1992). Field-Programmable Gate Arrays. doi:10.1007/978-1-4615-3572-0Lee, E. K. F., & Gulak, P. G. (1992). Field programmable analogue array based on MOSFET transconductors. Electronics Letters, 28(1), 28-29. doi:10.1049/el:19920017Lee, E. K. F., & Gulak, P. G. (s. f.). A transconductor-based field-programmable analog array. Proceedings ISSCC ’95 - International Solid-State Circuits Conference. doi:10.1109/isscc.1995.535521Pérez, D., Gasulla, I., & Capmany, J. (2018). Field-programmable photonic arrays. Optics Express, 26(21), 27265. doi:10.1364/oe.26.027265Zheng, D., Doménech, J. D., Pan, W., Zou, X., Yan, L., & Pérez, D. (2019). Low-loss broadband 5  ×  5 non-blocking Si3N4 optical switch matrix. Optics Letters, 44(11), 2629. doi:10.1364/ol.44.002629Densmore, A., Janz, S., Ma, R., Schmid, J. H., Xu, D.-X., Delâge, A., … Cheben, P. (2009). Compact and low power thermo-optic switch using folded silicon waveguides. Optics Express, 17(13), 10457. doi:10.1364/oe.17.010457Song, M., Long, C. M., Wu, R., Seo, D., Leaird, D. E., & Weiner, A. M. (2011). Reconfigurable and Tunable Flat-Top Microwave Photonic Filters Utilizing Optical Frequency Combs. IEEE Photonics Technology Letters, 23(21), 1618-1620. doi:10.1109/lpt.2011.2165209Rudé, M., Pello, J., Simpson, R. E., Osmond, J., Roelkens, G., van der Tol, J. J. G. M., & Pruneri, V. (2013). Optical switching at 1.55 μm in silicon racetrack resonators using phase change materials. Applied Physics Letters, 103(14), 141119. doi:10.1063/1.4824714Zheng, J., Khanolkar, A., Xu, P., Colburn, S., Deshmukh, S., Myers, J., … Majumdar, A. (2018). GST-on-silicon hybrid nanophotonic integrated circuits: a non-volatile quasi-continuously reprogrammable platform. Optical Materials Express, 8(6), 1551. doi:10.1364/ome.8.001551Edinger, P., Errando-Herranz, C., & Gylfason, K. B. (2019). Low-Loss MEMS Phase Shifter for Large Scale Reconfigurable Silicon Photonics. 2019 IEEE 32nd International Conference on Micro Electro Mechanical Systems (MEMS). doi:10.1109/memsys.2019.8870616Carroll, L., Lee, J.-S., Scarcella, C., Gradkowski, K., Duperron, M., Lu, H., … O’Brien, P. (2016). Photonic Packaging: Transforming Silicon Photonic Integrated Circuits into Photonic Devices. Applied Sciences, 6(12), 426. doi:10.3390/app6120426Bahadori, M., Gazman, A., Janosik, N., Rumley, S., Zhu, Z., Polster, R., … Bergman, K. (2018). Thermal Rectification of Integrated Microheaters for Microring Resonators in Silicon Photonics Platform. Journal of Lightwave Technology, 36(3), 773-788. doi:10.1109/jlt.2017.2781131Cocorullo, G., Della Corte, F. G., Rendina, I., & Sarro, P. M. (1998). Thermo-optic effect exploitation in silicon microstructures. Sensors and Actuators A: Physical, 71(1-2), 19-26. doi:10.1016/s0924-4247(98)00168-xZecevic, N., Hofbauer, M., & Zimmermann, H. (2015). Integrated Pulsewidth Modulation Control for a Scalable Optical Switch Matrix. IEEE Photonics Journal, 7(6), 1-7. doi:10.1109/jphot.2015.2506153Seok, T. J., Quack, N., Han, S., & Wu, M. C. (2015). 50×50 Digital Silicon Photonic Switches with MEMS-Actuated Adiabatic Couplers. Optical Fiber Communication Conference. doi:10.1364/ofc.2015.m2b.4Zortman, W. A., Trotter, D. C., & Watts, M. R. (2010). Silicon photonics manufacturing. Optics Express, 18(23), 23598. doi:10.1364/oe.18.023598Mower, J., Harris, N. C., Steinbrecher, G. R., Lahini, Y., & Englund, D. (2015). High-fidelity quantum state evolution in imperfect photonic integrated circuits. Physical Review A, 92(3). doi:10.1103/physreva.92.032322Pérez, D., & Capmany, J. (2019). Scalable analysis for arbitrary photonic integrated waveguide meshes. Optica, 6(1), 19. doi:10.1364/optica.6.000019Oton, C. J., Manganelli, C., Bontempi, F., Fournier, M., Fowler, D., & Kopp, C. (2016). Silicon photonic waveguide metrology using Mach-Zehnder interferometers. Optics Express, 24(6), 6265. doi:10.1364/oe.24.006265Chen, X., & Bogaerts, W. (2019). A Graph-based Design and Programming Strategy for Reconfigurable Photonic Circuits. 2019 IEEE Photonics Society Summer Topical Meeting Series (SUM). doi:10.1109/phosst.2019.8795068Zibar, D., Wymeersch, H., & Lyubomirsky, I. (2017). Machine learning under the spotlight. Nature Photonics, 11(12), 749-751. doi:10.1038/s41566-017-0058-3Lopez, D. P. (2020). Programmable Integrated Silicon Photonics Waveguide Meshes: Optimized Designs and Control Algorithms. IEEE Journal of Selected Topics in Quantum Electronics, 26(2), 1-12. doi:10.1109/jstqe.2019.2948048Harris, N. C., Bunandar, D., Pant, M., Steinbrecher, G. R., Mower, J., Prabhu, M., … Englund, D. (2016). Large-scale quantum photonic circuits in silicon. Nanophotonics, 5(3), 456-468. doi:10.1515/nanoph-2015-0146Spring, J. B., Metcalf, B. J., Humphreys, P. C., Kolthammer, W. S., Jin, X.-M., Barbieri, M., … Walmsley, I. A. (2012). Boson Sampling on a Photonic Chip. Science, 339(6121), 798-801. doi:10.1126/science.1231692O’Brien, J. L., Furusawa, A., & Vučković, J. (2009). Photonic quantum technologies. Nature Photonics, 3(12), 687-695. doi:10.1038/nphoton.2009.229Kok, P., Munro, W. J., Nemoto, K., Ralph, T. C., Dowling, J. P., & Milburn, G. J. (2007). Linear optical quantum computing with photonic qubits. Reviews of Modern Physics, 79(1), 135-174. doi:10.1103/revmodphys.79.135Politi, A., Cryan, M. J., Rarity, J. G., Yu, S., & O’Brien, J. L. (2008). Silica-on-Silicon Waveguide Quantum Circuits. Science, 320(5876), 646-649. doi:10.1126/science.1155441Politi, A., Matthews, J., Thompson, M. G., & O’Brien, J. L. (2009). Integrated Quantum Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 15(6), 1673-1684. doi:10.1109/jstqe.2009.2026060Thompson, M. G., Politi, A., Matthews, J. C. F., & O’Brien, J. L. (2011). Integrated waveguide circuits for optical quantum computing. IET Circuits, Devices & Systems, 5(2), 94. doi:10.1049/iet-cds.2010.0108Silverstone, J. W., Bonneau, D., O’Brien, J. L., & Thompson, M. G. (2016). Silicon Quantum Photonics. IEEE Journal of Selected Topics in Quantum Electronics, 22(6), 390-402. doi:10.1109/jstqe.2016.2573218Poot, M., Schuck, C., Ma, X., Guo, X., & Tang, H. X. (2016). Design and characterization of integrated components for SiN photonic quantum circuits. Optics Express, 24(7), 6843. doi:10.1364/oe.24.006843Saleh, M. F., Di Giuseppe, G., Saleh, B. E. A., & Teich, M. C. (2010). Modal and polarization qubits in Ti:LiNbO_3 photonic circuits for a universal quantum logic gate. Optics Express, 18(19), 20475. doi:10.1364/oe.18.020475Harris, N. C., Carolan, J., Bunandar, D., Prabhu, M., Hochberg, M., Baehr-Jones, T., … Englund, D. (2018). Linear programmable nanophotonic processors. Optica, 5(12), 1623. doi:10.1364/optica.5.001623Qiang, X., Zhou, X., Wang, J., Wilkes, C. M., Loke, T., O’Gara, S., … Matthews, J. C. F. (2018). Large-scale silicon quantum photonics implementing arbitrary two-qubit processing. Nature Photonics, 12(9), 534-539. doi:10.1038/s41566-018-0236-yLee, B. G., & Dupuis, N. (2019). Silicon Photonic Switch Fabrics: Technology and Architecture. Journal of Lightwave Technology, 37(1), 6-20. doi:10.1109/jlt.2018.2876828Cheng, Q., Rumley, S., Bahadori, M., & Bergman, K. (2018). Photonic switching in high performance datacenters [Invited]. Optics Express, 26(12), 16022. doi:10.1364/oe.26.016022Wonfor, A., Wang, H., Penty, R. V., & White, I. H. (2011). Large Port Count High-Speed Optical Switch Fabric for Use Within Datacenters [Invited]. Journal of Optical Communications and Networking, 3(8), A32. doi:10.1364/jocn.3.000a32Hamamoto, K., Anan, T., Komatsu, K., Sugimoto, M., & Mito, I. (1992). First 8×8 semiconductor optical matrix switches using GaAs/AlGaAs electro-optic guided-wave directional couplers. Electronics Letters, 28(5), 441. doi:10.1049/el:19920278Van Campenhout, J., Green, W. M., Assefa, S., & Vlasov, Y. A. (2009). Low-power, 2×2 silicon electro-optic switch with 110-nm bandwidth for broadband reconfigurable optical networks. Optics Express, 17(26), 24020. doi:10.1364/oe.17.024020Dupuis, N., Lee, B. G., Rylyakov, A. V., Kuchta, D. M., Baks, C. W., Orcutt, J. S., … Schow, C. L. (2015). D

Industrial and Technological Applications of Power Electronics Systems

The Special Issue "Industrial and Technological Applications of Power Electronics Systems" focuses on: - new strategies of control for electric machines, including sensorless control and fault diagnosis; - existing and emerging industrial applications of GaN and SiC-based converters; - modern methods for electromagnetic compatibility. The book covers topics such as control systems, fault diagnosis, converters, inverters, and electromagnetic interference in power electronics systems. The Special Issue includes 19 scientific papers by industry experts and worldwide professors in the area of electrical engineering

Advancements in Real-Time Simulation of Power and Energy Systems

Modern power and energy systems are characterized by the wide integration of distributed generation, storage and electric vehicles, adoption of ICT solutions, and interconnection of different energy carriers and consumer engagement, posing new challenges and creating new opportunities. Advanced testing and validation methods are needed to efficiently validate power equipment and controls in the contemporary complex environment and support the transition to a cleaner and sustainable energy system. Real-time hardware-in-the-loop (HIL) simulation has proven to be an effective method for validating and de-risking power system equipment in highly realistic, flexible, and repeatable conditions. Controller hardware-in-the-loop (CHIL) and power hardware-in-the-loop (PHIL) are the two main HIL simulation methods used in industry and academia that contribute to system-level testing enhancement by exploiting the flexibility of digital simulations in testing actual controllers and power equipment. This book addresses recent advances in real-time HIL simulation in several domains (also in new and promising areas), including technique improvements to promote its wider use. It is composed of 14 papers dealing with advances in HIL testing of power electronic converters, power system protection, modeling for real-time digital simulation, co-simulation, geographically distributed HIL, and multiphysics HIL, among other topics

FPGA-based High Performance Diagnostics For Fusion

High performance diagnostics are an important aspect of fusion research. Increasing shot-lengths paired with the requirement for higher accuracy and speed make it mandatory to employ new technology to cope with the increasing demands on digitization and data handling. Field programmable gate arrays (FPGAs) are well known in high performance applications. Their ability to handle multiple fast data streams whilst remaining programmable make them an ideal tool for diagnostic development. Both the improvement of old and the design of new diagnostics can benefit from FPGA-technology and increase the amount of accessible physics significantly. In this work the developments on two FPGA-based diagnostics are presented. In the first part a new open-hardware low-cost FPGA-based digitizer is presented for the MAST-Upgrade (MAST-U) integral electron density interferometer. The system is shown to have an optically limited phase accuracy and a detection bandwidth of over 3.5 MHz. Data is acquired continuously at 20 MS/s and streamed to an acquisition PC via optical fiber. By employing a dual-FPGA approach real-time processing of the density signal can be achieved despite severly limited resources, thus providing a control signal for the MAST-U plasma control system system with less than 8 μs latency. Due to MAST-U being still inoperable, in-situ testing has been conducted on the ASDEX Upgrade, where fast wave physics up to 3.5 MHz could first be observed. The second part presents developments to the Synthetic Aperture Microwave Imaging (SAMI) diagnostic. In addition to improving the utilization of long shot-lengths and enabling dual-polarized acquisition the system has been enhanced to continuously acquire active probing profiles for 2D Doppler back-scattering (DBS), a technique recently developed using SAMI. The aim is to measure pitch angle profiles to derive the edge current density. SAMI has been transferred to the NSTX-Upgrade and integrated into the experiment’s infrastructure, where it has been acquiring data since May 2016. As part of this move an investigation into near-field effects on SAMI’s image reconstruction algorithms was conducted