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[EN] This work describes a set of teaching materials that have been developed to support the learning of digital control. In particular, it presents a set of interactive tools and the project Duino-Based Learning (DBL) that has been designed to develop experimental practices of digital control using Arduino. In addition, the paper depicts the contents of a digital control course, taught in the framework of an industrial engineering degree, and how the developed tools are used in its teaching., El trabajo de E. Lerma ha sido financiado por la donación de Mathworks UPC-I-01523. El trabajo de R. Griñó ha sido parcialmente financiado por el Gobierno de España a través de la Agencia Estatal de Investigación Proyecto DPI2017-85404-P, la Generalitat de Catalunya a través del Proyecto 2017 SGR 872 y la donación de Mathworks UPC-I-01523.
El trabajo de R. Costa-Castelló ha sido parcialmente financiado por el Gobierno de España a través de la Agencia Estatal de Investigación Proyecto DOVELAR ref. RTI2018-096001-B-C32 (MCIU/AEI/FEDER, UE) y “María de Maeztu Seal of Excellence to IRI” (MDM-2016-0656), la Generalitat de Catalunya a través del Proyecto 2017 SGR 482 y la donación de Mathworks UPC-I-01523.

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper presents a feedback linearization-based control strategy for a a magnetically coupled multiport dc-dc converter aimed at automotive applications. Essentially, a transformation of control and state variables is proposed in such a way that the resulting system becomes linear and decoupled. Then, a conventional PI controller is devised that renders asymptotic stability, as well as robustness to resistive load uncertainty and presence of constant power loads. The inversion of the control transformation, which involves nonlinear terms, is carried out using linear approximations with no significant performance decay. Hence, simplicity and efficiency are the main features of the control design. The proposal is validated via realistic numerical simulations, Peer Reviewed

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper proposes a new sliding mode control based on a non-linear switching surface that provides a suboptimal current-limited start-up response in step-down converters. The main idea behind the design consists in combining different switching surfaces. The first one forces the system trajectories to track a constant current path until the output voltage error is small. A non-singular terminal switching surface then drives the trajectories to the vicinity of the steady state operating point. Finally, a first order switching surface regulates the steady state providing very good rates of load and line regulation. The paper presents the design guidelines of the suboptimal sliding mode control and the experimental evaluation that confirms the effectiveness of the proposal., This work was partially supported by the Government of Spain through the Agencia Estatal de Investigacion´ Project DPI2017-85404-P and by the Generalitat de Catalunya through the Project 2017 SGR 872., Peer Reviewed

Permanent magnet synchronous machines (PMSM) are widely used in the automotive industry for electric vehicle (EV) and hybrid electric vehicle (HEV) propulsion systems, where the trend is to achieve high mechanical speeds. High speeds inevitably imply high current electrical frequencies, which can lead to a lack of controllability when using field oriented control (FOC) due to sampling period constraints. In this work, a comprehensive discrete-time model is fully developed to assess the stability issues in the widely used FOC. A speed-adaptive control structure that overcomes these stability problems and extends the speed operation range of the PMSM is presented. Also, a numerical methodology from which the maximum operating stable frequency can be computed in advance of any experimentation, is developed. All contributions are accompanied and supported by numerical results obtained from an accurate MATLAB/Simulink model., Peer Reviewed

This paper presents a sliding mode control strategy for a dc-dc dual active bridge converter. The controller is based on a truncated model obtained using the generalized state space averaging method that transforms the mixed dcac dynamics of the converter into a regulation problem. The proposed controller, that uses a dynamic extension to overcome the structural problem of the non-affine control input, provides good results in terms of performance and robustness. Numerical simulations are included to validate the proposed modelling methodology and the control design., Peer Reviewed

Constant power loads (CPLs) in power systems have a destabilizing effect that gives rise to significant oscillations or to network collapse, motivating the development of new methods to analyse their effect in AC and DC power systems. A sine qua non condition for this analysis is the availability of a suitable mathematical model for the CPL. In the case of DC systems power is simply the product of voltage and current, hence a CPL corresponds to a first–third quadrant hyperbola in the loads voltage–current plane. The same approach is applicable for balanced three-phase systems that, after a rotation of the coordinates to the synchronous frame, can be treated as a DC system. Modelling CPLs for single-phase (or unbalanced poly-phase) AC systems, on the other hand, is a largely unexplored area because in AC systems (active and reactive) power involves the integration in a finite window of the product of the voltage and current signals. In this paper we propose a simple dynamic model of a CPL that is suitable for the analysis of single-phase AC systems. We give conditions on the tuning gains of the model that guarantee the CPL behaviour is effectively captured., Peer Reviewed

En este trabajo se describen un conjunto de materiales pedagógicos que han sido desarrollados para dar soporte a la docencia del control digital. En particular, se presentan un conjunto de herramientas interactivas y el proyecto Duino-Based Learning (DBL) pensado para desarrollar prácticas experimentales de control digital utilizando Arduino. Además, se describe el contenido de un curso de control digital, que  se imparte en el marco de una titulación de ingeniería industrial, y como se utilizan las diferentes herramientas desarrolladas en su docencia., Peer Reviewed

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This article explores a nonlinear, adaptive controller aimed at increasing the stability margin of a direct-current (dc), small-scale, electrical network containing an unknown constant power load (CPL). Due to its negative incremental impedance, this load reduces the effective damping of the network, which may lead to voltage oscillations and even to voltage collapse. To overcome this drawback, we consider the incorporation of a controlled dc-dc power converter in parallel with the CPL. The design of the control law for the converter is particularly challenging due to the existence of unmeasured states and unknown parameters. We propose a standard input-output linearization stage, to which a suitably tailored adaptive observer is added. The good performance of the controller is validated through experiments on a small-scale network., Peer Reviewed

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., We describe a multicellular approach to control a target cell population endowed with a bistable toggle-switch. The idea is to engineer a synthetic microbial consortium consisting of three different cell populations. In such a consortium, two populations, the Togglers, responding to some reference input, can induce the switch of a bistable memory mechanism in a third population, the Targets, so as to activate or deactivate some additional functionalities in the cells. Communication among the three populations is established by orthogonal quorum sensing molecules that are used to close a feedback control loop across the populations. The control design is validated via in-silico experiments in BSim, a realistic agent-based simulator of bacterial populations.

This paper compares four sliding-mode control strategies for a dual active bridge. The proposed control algorithms define different switching functions resulting in first-and second-order controllers, and using both discontinuous and continuous sliding-mode algorithms. The paper details the design stage and includes simulation and experimental tests to better compare the performance for each control scheme., Peer Reviewed

© <2020>. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/, One way to optimize the operation of chemical systems consists on using closed loop controls while the system is operated. This way, it is possible to optimize the operating point in the plant, process or chemical system so that certain quantities are maximized/minimized or time responses are reduced. In the design of the closed loop controls, though, one of the problems is the large number of configuration parameters involved and the uncertainties in the system. The objective of this paper is to present how recently proposed controls, exploiting time-scale separation, allow to configure their closed loop configuration parameters from open-loop measurements. These controls have been proposed to accelerate the time response of metal-oxide gas sensors by operating at constant surface potential. The main result of the paper explains the link between the open loop measurements and closed loop operation. Experiments are provided using a commercial off-the-shelf Microelectromechanical gas sensor., The work of M. Dominguez-Pumar, L. Kowalski and V. Jimenez was partially supported by the Government of Spain through the Agencia Estatal de Investigación Projects ESP2016-79612-C3-2-R and RTI2018-098728-B-C33 and by the Generalitat de Catalunya through the Project 2017 SGR 279. The work of J.M. Olm was partially supported by the Government of Spain through the Agencia Estatal de Investigación Project DPI2017-85404-P and by the Generalitat de Catalunya through the Project 2017 SGR 872., Peer Reviewed

This work presents the design guidelines of a control for direct regulation of the voltage amplitude at the connection point of a single-phase grid-connected PV inverter. The parameters of the control are designed for ensuring local asymptotic stability for a given range of the impedance. Furthermore, the control includes a strategy of active power curtailment in order to avoid the injection of a large amount of reactive power to the grid. Numerical simulations confirm the expected voltage regulation and the control robustness with respect to the grid impedance variations without the requirement of any estimation or measure of the actual impedance. © 2018 IEEE., Peer Reviewed

© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This article proposes a family of phase-locked loop schemes based on sliding modes. The use of sliding mode algorithms ensures fast response and global stability. In particular, two new algorithms are presented, both based on a complex framework for representing three-phase signals. This article compares the obtained algorithms with the traditional schemes, and a faster response is obtained when sliding modes are used. Additionally, as an application example, the algorithm is combined with a complex-coefficient filter that allows an easy identification of both positive and negative sequence harmonics. The proposed algorithms are illustrated by numerical simulations and experimentally validated using a digital signal processor., Peer Reviewed

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper presents a novel grid current control of a grid-connected voltage source converter with an LCL filter. The proposed control method uses an H 8 synthesis method to shape the input admittance of the converter, to track a given current reference, and/or to limit the controller actuation at different frequency ranges. The converter admittance is shaped, both in magnitude and phase, following a model reference defined by the designer in the frequency domain. By specifying a low admittance magnitude reference, the optimization algorithm will obtain a controller that actively damp the filter resonance and attenuate/reject the grid voltage oscillations, either in a wide frequency range or concentrated at the main harmonic frequencies. Additionally, the proposed controller design methodology takes advantage of its admittance phase shaping capability to improve the system robustness in front of grid uncertainties and minimizing converter impact over grid stability due to its positive-real nature. The synthesized controller only measures the grid current and voltage to achieve the aforementioned results, reducing the number of sensors (and their associated cost) required for its implementation. Experimental results illustrate the correct behavior of the closedloop system with the designed controller in time and frequency domain.

The main benefits of fuzzy logic control (FLC) allow a qualitative knowledge of the desired system’s behavior to be included as IF-THEN linguistic rules for the control of dynamical systems where either an analytic model is not available or is too complex due, for instance, to the presence of nonlinear terms. The computational structure requires the definition of the FLC parameters namely, membership functions (MF) and a rule base (RB) defining the desired control policy. However,
the optimization of the FLC parameters is generally carried out by means of a trial and error procedure or, more recently by using metaheuristic nature-inspired algorithms, for instance, particle swarm optimization, genetic algorithms, ant colony optimization, cuckoo search, etc. In this regard, the cuckoo search (CS) algorithm as one of the most promising and relatively recent developed nature-inspired algorithms, has been used to optimize FLC parameters in a limited variety of applications to determine the optimum FLC parameters of only the MF but not to the RB, as an extensive search in the literature has shown. In this paper, an optimization procedure based on the CS algorithm is presented to optimize all the parameters of the FLC, including the RB, and it is applied to a nonlinear magnetic
levitation system. Comparative simulation results are provided to validate the features improvement of such an approach which can be extended to other FLC based control systems., Peer Reviewed

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper present two different approaches for modelling a magnetically coupled multiport dc-dc converter. First, from the magnetic coupling equations, the instantaneous dynamic model is obtained. Secondly, a behavioural dynamic model, based on averaging the power flowing among the ports, is derived. Some numerical simulations compare the temporal evolutions with the two obtained models, Peer Reviewed

The objective of this paper is to explain how quantization noise-shaping can be achieved for the output bitstream of sigma-delta controls of surface potential (SP) in MOX gas sensors. These controllers use temperature modulation to keep constant the surface potential of the nanostructures. The rate equations describing the time evolution of the state variables in the sensing layer (concentration of ionized species on the surface of the nanostructures) are nonlinear. It will be shown that under the condition of constant surface potential, the sensor using the proposed temperature modulations can be seen as an example of affine switching and that quantization noise shaping
may be achieved., Peer Reviewed

Sensorless control of Electric Vehicle (EV) drives is considered to be an effective approach to improve system reliability and to reduce component costs. In this paper, relevant aspects relating to the sensorless operation of EVs are reported. As an initial contribution, a hybrid sensorless control algorithm is presented that is suitable for a variety of synchronous machines. The proposed method is simple to implement and its relatively low computational cost is a desirable feature for automotive microprocessors with limited computational capabilities. An experimental validation of the proposal is performed on a full-scale automotive grade platform housing a 51¿kW Permanent Magnet assisted Synchronous Reluctance Machine (PM-assisted SynRM). Due to the operational requirements of EVs, both the strategy presented in this paper and other hybrid sensorless control strategies rely on High Frequency Injection (HFI) techniques, to determine the rotor position at standstill and at low speeds. The introduction of additional high frequency perturbations increases the power losses, thereby reducing the overall efficiency of the drive. Hence, a second contribution of this work is a simulation platform for the characterization of power losses in both synchronous machines and a Voltage Source Inverters (VSI). Finally, as a third contribution and considering the central concerns of efficiency and autonomy in EV applications, the impact of power losses are analyzed. The operational requirements of High Frequency Injection (HFI) are experimentally obtained and, using state-of-the-art digital simulation, a detailed loss analysis is performed during real automotive driving cycles. Based on the results, practical considerations are presented in the conclusions relating to EV sensorless control., Peer Reviewed

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper focuses on the design of an active-damping controller that shapes the dynamics of an LCL grid connected voltage source converter (VSC) to mimic an L-filter connected VSC. This makes possible to use simpler classical proportional plus resonant or proportional plus integral controllers design methods to regulate the grid current with minimum penalties in both performance and stability margins. The active-damping design follows a model-reference approach and is synthesized through a (sub)optimal H 8 algorithm. The controller uses the grid current and point of common coupling voltage, although it allows the selection of a different set of measurements. Effectiveness of the method is demonstrated with timeand frequency-domain experimental results., Peer Reviewed

Requirements for electric vehicle (EV) propulsion systems—i.e., power density, switching frequency and cost—are becoming more stringent, while high reliability also needs to be ensured to maximize a vehicle’s life-cycle. Thus, the incorporation of a thermal management strategy is convenient, as most power inverter failure mechanisms are related to excessive semiconductor junction temperatures. This paper proposes a novel thermal management strategy which smartly varies the switching frequency to keep the semiconductors’ junction temperatures low enough and consequently extend the EV life-cycle. Thanks to the proposal, the drivetrain can operate safely at maximum attainable performance limits. The proposal is validated through simulation in an advanced digital platform, considering a 75-kW in-wheel Interior Permanent Magnet Synchronous Machine (IPMSM) drive fed by an automotive Silicon Carbide (SiC) power converter., This work has been supported in part by the European Commission through ECSEL Joint Undertaking (JU) under Grant Agreement No. 783174 (HiPERFORM project), by the Government of the Basque Country within the research program ELKARTEK as the projects ELPIVE (KK-2019/0006) and ENSOL 2 (KK-2020/00077), by the Government of the Basque Country within the fund for research groups of the Basque University system IT978-16, by the Government of Spain through the Agencia Estatal de Investigación Project DPI2017-85404-P, and by the Generalitat de Catalunya through the Project 2017 SGR 872., Peer Reviewed

Este artículo presenta una estrategia adaptativa para regular la tension de salida de un convertidor dc-dc ´ multipuerto acoplado magneticamente destinado a aplicaciones áutomotrices. El algoritmo propuesto brinda solidez frente a incertidumbre en la carga resistiva y presencia de cargas de potencia constantes desconocidas. El analisis te ´ orico, que utiliza ´ la teoría de la estabilidad de Lyapunov, se valida mediante simulaciones numericas realistas., Peer Reviewed

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper proposes a nonlinear, output feedback, adaptive controller to increase the stability margin of a direct-current (DC), small-scale, electrical network containing an unknown constant power load. Due to their negative incremental impedance, constant power loads are known to reduce the effective damping of a network, leading to voltage oscillations and even to network collapse. To overcome this drawback, we consider the incorporation of a controlled DC-DC power converter in parallel with the constant power load. The design of the control law for the converter is particularly challenging due to the existence of unmeasured states and unknown parameters. We propose a standard input-output linearization stage, to which a suitably tailored adaptive observer is added. The good performance of the controller is evaluated with numerical simulations, Peer Reviewed

In this paper, an energy management strategy based on microgrid power forecasting is applied to a residential grid-connected electro-thermal microgrid with the aim of smoothing the power profile exchanged with the grid. The microgrid architecture under study considers electrical and thermal renewable generation, energy storage system (ESS), and loads. The proposed strategy manages the energy stored in the ESS to cover part of the energy required by the thermal generation system for supplying domestic hot water to the residence. The simulation results using real data and the comparison with previous strategy have demonstrated the effectiveness of the proposed strategy., Peer Reviewed

Trabajo presentado en el 12th IFAC Symposium on Advances in Control Education ACE , celebrado en Philadelphia, Pennsylvania (Estados Unidos), del 7 al 9 de julio de 2019, In this work, the subject of digital control taught in a generic engineering degree is described. In particular, the contents of the course, the experimental environment and the interactive tools used in teaching are discussed. This work collects the teaching experience obtained during the past twenty years by the teaching team of this subject at the Barcelona School of Industrial Engineering of the Universitat Politecnica de Catalunya., The work of R. Costa-Castello was partially supported by
the Government of Spain through the Agencia Estatal de
Investigacion projects DPI2015-69286-C3-2-R and Marıa
de Maeztu Seal of Excellence to IRI (MDM-2016-0656),
by the Generalitat de Catalunya through the Project 2017
SGR 482 and by the donation of Mathworks UPC-I-01523.
The work of R. Griño was partially supported by the
Government of Spain through the Agencia Estatal de Investigaci´on Project DPI2017-85404-P, by the Generalitat
de Catalunya through the Project 2017 SGR 872 and by
the donation of Mathworks UPC-I-01523.
The work of E. Lerma was partially supported by the
donation of Mathworks UPC-I-01523.
The work of S. Dormido was partially supported by the
Government of Spain through the Agencia Estatal de Investigacion projects DPI2017-84259-C2-2-R.