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This paper presents two hybrid control topologies; the topologies are designed by combining artificial intelligence approaches and sliding-mode control methodology. The first topology mixes the learning algorithm for multivariable data analysis (LAMDA) approach with sliding-mode control. The second offers a Takagi-Sugeno multimodel approach, internal model, and sliding-mode control. The process under study is a nonlinear pH neutralization process with high nonlinearities and time-varying parameters. The pH process is simulated for multiple reference changes, disturbance rejection, and noise in the transmitter. Performance indices are used to compare the proposed approaches quantitatively. The hybrid control topologies enhance the performance and robustness of the pH process under study.

This document presents the development of a low-cost industrial data server for communicating Modbus TCP devices and Windows applications by using a database as a temporary storage space. The performance of developed data server was evaluated by integrating it with an commercial industrial Windows application, were data server demonstrated an adequate behavior. The proposed application is based largely on free software, Java and MySQL, to reduce its cost and to become it an accessible option for industries with low investment capacity. Then, this development aims to offer a low-cost alternative for implementing a supervisory control system.

This document presents a methodology to design and implement a Distributed Load Frequency Control (D_LFC) scheme in power systems. The proposal is based on a control law that feed backs internal rotor angle deviation to the governor of every generator. As a result, the governor acts as a distributed controller for frequency and transferred power, which uses local measurements. Although information exchange between governors is not performed, they describe a synchronized behaviour because of the natural coupling between the generators' speed. Control response times are lower than centralized schemes such as the Automatic Generation Control (AGC) due to the fact that control actions can be carried out locally near the disturbance. Simulation in the IEEE 39-Bus System on PowerFactory Digsilent permit us to compare the performance of D_LFC with respect to AGC.

This paper presents the development and pilot implementation of the methodological proposal for the improvement to the efficiency and cybersecurity of the SCADA communication network in EmelNorte substations. This is justified by the fact that the modern substations operation requires that the SCADA will become to an open system, which can be integrated with others systems related with administration and management of Energy Business. This situation, on the one hand, bring with it the need for a SCADA communication network that should be characterized by a high availability and efficiency, but on the other hand, as the SCADA becomes an open system, its cybersecurity could be compromised. In this regard, a design methodology for improving efficiency and cybersecurity of the SCADA communication network is developed by taking as references standards IEC-61850 and NERC-CIP-7. This methodology propose design guidelines for: (1) LAN architecture design in substations, (2) administration and management of SCADA communication network, and (3) cybersecurity of SCADA communication network. In order to validate the proposed guidelines, these were implemented in the communication network of substation “El Retorno”, and then efficiency and cybersecurity were evaluated and contrasted to that of network before the implementation. The results show significant performance improvements, and with it the potential benefits of the methodology implementation are evidenced.

Ecuador’s Transmission System (SNT) is integrated by 60 substations, 44 of them have a Substation Automation System (SAS) and 5 of these SAS are obsolete. When a failure of any protection/control device occurs in an obsolete SAS, the lack of spare parts drives the substation to a critical state that could compromise the service availability since a proper substation operation cannot be accomplished. In this regard, TRANSELECTRIC set up the plan to update around 20 substations which are within its field of action. To this end, retrofit engineering of a transmission line-bay under the IEC 61850 guidelines is developed and includes the standardization of signals, the reengineering of SAS components, and the standardization of the substation operator interfaces. This engineering is then applied to INGA 1 Bay (Pomasqui Substation) and its evaluation is accomplished in laboratory by the emulation of such bay with the designed automation system. To validate the proposed retrofit, the architecture and dataflow of Pomasqui Substation are emulated as well, to evaluate the automation system performance under practical operational scenarios. After the experiments, the results show the feasibility of the proposed retrofit.

The development of DeviceNet communication drivers and their electronic data sheets (EDS) for configuring them in automation software applications are proposed. In this regard, Common Industrial Protocol (CIP) Standard established by ODVA is reviewed, and a commercial DeviceNet network is analyzed in order to define hardware and software requirements for implementing the proposed drivers. Then, prototypes for discrete as well as analog sensors are implemented; their EDS files are developed too. After, the implemented drivers are integrated in a commercial DeviceNet network for validating their performance by monitoring their operation through RSNetWorx for DeviceNet. The developed prototypes and their EDS files shown a proper operation according to proposed aims. Therefore, by this work, the basis for the development of DeviceNet communication drivers for sensors were established.

This paper presents the development of low-cost industrial software focused on industries with limited investment capacity. This propose aims to promote SCADA System integration in process of the small and mid-sized industries. In this regard, the proposed software includes both a Modbus communication application and a HMI based on a web server application for SCADA System implementation. Finally, performance of developed software is tested through the emulation of a practical process.

This paper presents a decentralized control of the generator’s internal angle for the removal of power deviation in transmission lines in an interconnected power system. This scheme incorporates the integral of the transferred power deviation through the lines as part of the governor’s control reference. The use of this signal produces a system response that is mathematically comparable to a second-order consensus which acts as a coupling law between the generators’ angle deviations that forces consensus. Mathematical results are presented for a linearized model whilst simulation results are produced for a non-linear model of the power system.

This paper proposes a way for the practical implementation of a decentralized scheme for the removal of power deviation in transmission lines in a power system. The proposal incorporates the local measurement of the transferred power through the transmission lines as part of the governor's control reference in order to attain a second-order consensus (SOC). SOC acts as a coupling law between the generators' angle deviations that forces consensus between them while removing transferred power deviation. Simulation results are presented for three different implementations of SOC. Also, SOC performance is analyzed by comparing it with AGC.

This article presents an analysis of the feasibility of executing wide-area monitoring and control functions in a distributed way in the power system, taking advantage of interconnected system's behavior that describes the power system. For this purpose, observability is analyzed when the state estimation is performed in a distributed way and only with local measurements. Also, power system is adjusted to a distributed cooperative control problem based on consensus algorithms. After the analysis presented, it can be concluded that the power system can be represented through a disaggregated model, based on models of interconnected subsystems, which proves the feasibility of executing monitoring or control tasks in a distributed way without information exchange with neighboring areas.

This paper presents a simulation study of an architecture of distributed cooperative controllers operating over a wide-area system, which employs consensus algorithms to attain a common objective among control areas, with limited information exchange. A 4-area case study for load frequency control (LFC) is used to illustrate the implementation of the distributed architecture and of a second order consensus algorithm. Topological analysis is employed to determine the minimum information exchange. Results demonstrate that the control scheme is feasible and allows to scale small-area and medium-area control schemes to wide-area control with minimum information exchange.

This paper reports on the development of a frequency inverter for speed control of an induction machine. The control is implemented on a 80C196MC microcontroller and the power system is implement using a three-phase bridge of IGBTs. Both, control and power circuit provide an output with variable voltage and frequency. The frequency and other parameters in the speed drive are manipulated from a human-machine-interface HMI