This chapter discusses leading problems linked to energy that the world is now confronting and to propose some ideas concerning possible solutions. Oil deserves special attention among all energy sources. Since the beginning of 1981, it has merely been continuing and enhancing the downward movement in consumption and prices caused by excessive rises, especially for light crudes such as those from Africa, and the slowing down of worldwide economic growth. Densely-populated oil-producing countries need to produce to live, to pay for their food and their equipment. If the economic growth of the industrialized countries were to be 4%, even if investment in the rational use of energy were pushed to the limit and the development of nonpetroleum energy sources were also pursued actively, it would be extremely difficult to prevent a sharp rise in prices. It is evident that it is absolutely necessary to pursue actively the development of coal, natural gas, and nuclear power if a physical shortage of energy is not to block economic growth.

World energy outlook

https://cyberleninka.org/article/n/412224.pdf

Smart Solar Panels: In-situ Monitoring of Photovoltaic Panels based on Wired and Wireless Sensor Networks☆

The paper describes a new curriculum for Engineering Education 4.0 based on the analysis of different references and essential relevant documents that explain the necessity to well-formed a new generation of professionals. Considering the technological change that world is going through, our current social environments and generational differences in a society focus on the extraneous and declares itself as the savior of the world. The university rises as a relevant and essential agent to ensure knowledge and development of competencies in this fourth industrial revolution, which has been called Industry 4.0 (I4.0). A series of digital technologies converge in applications transform the industrial processes so that they become more connected, reliable, predictable, resilient, and a high degree of certainty. All of this is due to the articulation of several capabilities of information technologies. Several efforts have been detonated in the world trying to better understand this evolution and in particular for Engineering Education towards the I4.0.

Engineering Education 4.0: — proposal for a new Curricula

This work presents a comparative study between a new approach for robust speed estimation in induction motor sensorless control, using a reduced order extended Kalman filter (EKF), and the one performed by the full order EKF. The new EKF algorithm uses a reduced order state-space model that is discretized in a particular and innovative way. In this case only the rotor flux components are estimated, besides the rotor speed, while the full order EKF also estimates stator current components. This new approach strongly reduces the execution time and simplifies the tuning of covariance matrices. The performance of speed estimation using both EKF techniques is compared with respect to computation effort, tuning of the algorithms, speed range including low speeds, load torque conditions and robustness relatively to motor parameter sensitivity.

/pdf/full-and-reduced-order-extended-kalman-filter-for-speed-3skzcqwmaf.pdf

Full and reduced order extended kalman filter for speed estimation in induction motor drives: a comparative study

A comprehensive review of topologies for photovoltaic I-V curve tracer

This paper presents an improved electronic circuit for testing photovoltaic (PV) modules or strings by tracing their I-V and P-V characteristics. It consists of an electronic fast varying load based on a power MOSFET controlled by means of an innovative sweeping gatesource voltage in order to improve the tracing of the I-V characteristics on an oscilloscope. In order to prevent damage of data acquisition systems and mainly for use with high voltage PV strings, galvanic isolation is introduced for the sweeping signal as well as current and voltage measurements. In spite of this improved characteristics, the developed electronic circuit keeps the advantages of low cost and simplicity. Experimental results obtained with the electronic circuit are presented.

/pdf/an-improved-electronic-circuit-for-tracing-the-i-v-3xlw01ve7u.pdf

An improved electronic circuit for tracing the I-V characteristics of photovoltaic modules and strings

This paper presents a simple, robust and low-cost instrument for tracing currentand power-voltage characteristics of photovoltaic modules or low voltage strings using either an oscilloscope or a LabVIEW application developed for this purpose. It consists of a flexible electronic circuit, developed from a previous work, based on a fast varying load, built with a power MOSFET, which is controlled by means of a suitable gate-source voltage control signal in order to improve the tracing of currentand powervoltage characteristics on an oscilloscope. The new developments of this work include a low-cost DAQ system and an application developed in LabVIEW, which enhances the functionalities and flexibility of the current-voltage tracer. The robustness was strongly improved in view of field tests for fault diagnosis analysis. All details of the electronic circuit are shown in this paper and experimental results obtained with the new instrument are presented.

/pdf/low-cost-instrument-for-tracing-current-voltage-3btm9f936f.pdf

Low-cost instrument for tracing current-voltage characteristics of photovoltaic modules

This paper presents a reflection on the results of an experimental curricula design which combined short-term project-oriented research and project-based learning in the field of electrical engineering and renewable energy. The experiment was based on the application of the Project-Based Learning methodology. The problem to be solved arose from a local company and was carried out at a master level in the Polytechnic Institute of Braganca in Portugal. This experiment aimed to contribute to the innovation and modernization of educational projects of professionally oriented programmes in higher education institutions. It also demonstrated some of the advantages and challenges of learning innovation. Feedback from the students was encouraging but the results of this experiment mainly pointed to the need that everyone must be prepared for change. The study contributes to understanding both why and how we need to foster educational shift in electrical engineering to educate students and enhance their engineering skills for the twenty-first century.

Innovative learning in engineering education: Experimenting with short-term project-oriented research and project-based learning

A new online identification methodology for estimation of the rotor flux components and the main electrical parameters of vector controlled induction motors is presented in this paper. The induction motor model is referred to the rotor reference frame for estimation of rotor flux and rotor parameters, and referred to the stator reference frame to estimate stator parameters. The stator parameters estimation is achieved by a prediction error method based on a model structure described by a linear regression that is independent of rotor speed and rotor parameters. The rotor flux components and rotor parameters are estimated by a reduced order extended Kalman filter, using a 4th-order state-space model structure where the state equation is described by matrices that are diagonal and independent of rotor speed as well as stator parameters. Both methods work in a boot-strap manner.

/pdf/a-new-online-identification-methodology-for-flux-and-58cmf00sp8.pdf

A new online identification methodology for flux and parameters estimation of vector controlled induction motors

This paper presents a new approach for the simultaneous identification of rotor flux components in the rotor reference frame and electrical parameters of a vector controlled induction motor, for real-time implementations, using an extended Kalman filter (EKF) and a reduced order model structure for lower computational effort. The proposed new method requires the measurement of motor speed, stator voltages and currents signals. Using a motor model structure with four electrical parameters, the estimation of flux space phasor and rotor parameters is presented The estimation is subsequently further extended to include the motor stator parameters and the results are analyzed as well as robustness. Simulated and experimental studies highlight the improvements brought by this new approach, mainly, a simple and reduced state equation, the introduced scalar output equation and lower computational cadency by using lower sampling frequencies in the proposed rotor reference frame.

/pdf/flux-and-parameters-identification-of-vector-controlled-forp1gj0ca.pdf

Vicente Leite

Papers

An improved electronic circuit for tracing the I-V characteristics of photovoltaic modules and strings

Low-cost instrument for tracing current-voltage characteristics of photovoltaic modules

Innovative learning in engineering education: Experimenting with short-term project-oriented research and project-based learning

A new online identification methodology for flux and parameters estimation of vector controlled induction motors

Flux and parameters identification of vector-controlled induction motor in the rotor reference frame