Elsevier

Electric Power Systems Research

Volume 130, January 2016, Pages 156-166
Electric Power Systems Research

Implementation of an educational real-time platform for relaying automation on smart grids

https://doi.org/10.1016/j.epsr.2015.09.003Get rights and content

Highlights

  • We designed and implemented a real-time teaching platform for relaying automation.

  • Performance was validated with COMTRADE and RT simulations of the grid.

  • Students can develop smart relaying applications with hardware-in-the-loop cases.

  • Students explore protective automation methodologies with appropriate realism.

  • ABET objectives were enhanced with undergraduate students.

Abstract

The increasing research work on power networks has produced important challenges on distribution systems. These multiple advances bring an inevitable need to reshape and modernize teaching methodologies in order to understand the different issues of the smart grid complexity. This paper presents the design and implementation of an interactive platform to assess Advanced Distribution Automation (ADA) with applications and solutions focused on relaying solutions for educational purposes on smart grid. The proposed architecture integrates hardware/software tools to emulate the distribution system's behavior and recreate selected signals. Different features are presented and validated from a basic case study, where the students are able to comprehend the main concepts of relaying devices. The operational functionality of the platform offers the required flexibility to link theory with practice, which is suitable to enhance the learning process and encourage the class innovation. The user can incorporate protective algorithms and automation solutions under a real-time environment with hardware-in-the-loop techniques, such as adaptive protections and reconfiguration methods to optimize the grid. The impact of this platform in educational courses and the development of undergraduate thesis is assessed over the last 5 years in the faculty, and ABET guidelines are included in the evaluation of five Program Educational Objectives (PEOs) to measure the influence on students. Further potential applications are also discussed.

Introduction

The engineering efforts are highly focused on strategies to reach a more reliable and efficient distribution system [1]; as result of these efforts, the research on smart grids offers multiple working fields to integrate modern equipment into the current infrastructure [2]. This enhancing process is coherent with the goals of Advanced Distribution Automation (ADA) [3], [4] and the continuous evolution of the research will enable to build the optimal grid of the future. Such challenges have been clearly defined in research and standardization as well: in grid equipment monitoring, fault location [5], isolation [6] and restoration [7], inclusion of renewable energy, electric vehicles, grid reconfiguration [8], adaptive protections, volt and var control, metering, event recording and communications infrastructure [9] are some of the examples of research priorities.

The attempt to improve reliability and power quality involve several applications on the smart grid, which require an important set of protection devices to monitor and control multiple relaying functions. This context has always been a priority in power engineering education [10], [11] and many advances are widely recognized in the last years of modeling [12], simulation [13] and laboratory platforms [14], [15], [16]. In consequence, the teaching approaches of power engineering and protective relaying control has turned into a constant innovative evolution; certainly, the role of digital modeling and simulation is encouraging all the teaching efforts to form a new generation of students, well prepared for the smart grid challenges applications and research. The study reported in this paper, fits a customized platform for general-purpose on relaying automation, based on a hardware/software integration.

The proposed platform, incorporates needs aim to improve the learning curve of students in different areas. An important part of this project lies in the simulation software DSSim-PC [17], a free tool also developed at Universidad de los Andes, based on the powerful EPRI's OpenDSS [18]. As it will be introduced later, the program structure is designed to be scalable, flexible and feasible to be replicated in hardware architectures that follow the platform requirements. These first two features of the proposed test bench generate a low cost for development, which is an important need when applying customized platforms for research and educational solutions. The study presented in this paper is part of two master's thesis and the applications were developed by last semester undergraduate students. This novel integration has been used as a tool for undergraduate thesis, continued education projects, and graduate projects over the past 2 years. A more detailed statistical analysis of the platform's impact of the Electrical Engineering program is presented in Section 5, the results demonstrate the evolution and motivation that this test bench has consequently caused in undergraduate students, not only for academic purposes but also because it approaches them to real applications in their professional careers.

The paper is organized as follows, the proposed platform of hardware and software integration as a real-time hardware-in-the-loop architecture is explained in Section 2; the design, performance and validation strategy is presented as well with a basic case of study. This system evaluates different scenarios and a set of results demonstrates the real time simulation advantages. In Section 4, the platform is assessed under two different applications of adaptive protections and a reconfiguration algorithm to optimize losses. A statistical analysis is presented to evaluate the educational impact of the proposed platform in undergraduate students. Conclusions are given at the end.

Section snippets

Designing a RT-HIL environment

Electrical networks are rapidly evolving into a more complex and smart functionality, so the methodology to analyze them should be improved in the same direction. In the case of protective relaying control techniques as well as in many other areas, the use of modeling and simulation tools combined with an effective hardware/software integration results in a great alternative to understand the smart grid. This section introduces the early attempts to include more realism within teaching

Fault scenario: a basic example

The following case is fully recreated in order to evaluate the platform's performance. A basic case of study is shown in Fig. 4. It is important to mention that the second load LD_2 is 4 times higher than LD_1. The first recloser SW_1 will have an overvoltage protection function on, this IED is identified with the relay BECO 7679 (black relay in Fig. 3); simultaneously, SW_2 will be programmed with a reclosing function with a TCC based on IEC Short-Time Inverse Curve C5 located on the SEL 751A

Adaptive protections

The inclusion of distributed generation (DG) in the future grids is inevitable, and the interaction with dynamic loads introduces a new context in protection coordination. The following case illustrates a basic example which allows the student to understand how complex this problem could be. This part is the result of an undergraduate project.

The case study is shown in Fig. 8a. It basically works with the real-time simulation of different fault current magnitudes. The student should practice

Conclusion

The paper presented an implemented real-time platform, which properly works for educational purposes of relaying control for smart grid applications. This platform is the first test bench based on a hardware–software integration with DSSim-PC; As an interesting improvement, a co-simulation of distribution system models from DSSim-PC interacts with real IEDs and protection devices. This characteristic brings a potential hardware-in-the-loop feature, which is suitable to develop Advanced

References (34)

  • D. Bernardon et al.

    Real-time reconfiguration of distribution network with distributed generation

    Electr. Power Syst. Res.

    (2014)
  • A. Conde

    An interactive software of distance relaying for analysis of electrical events and educational use

    Electr. Power Syst. Res.

    (2013)
  • R.F. Arritt et al.

    Distribution system analysis and the future smart grid

    IEEE Trans. Ind. Appl.

    (2011)
  • M. Pantelia et al.

    Situation awareness in power systems: theory, challenges and applications

    Electr. Power Syst. Res.

    (2015)
  • F. Zavoda

    Advanced Distribution Automation (ADA) applications and power quality in smart grids

  • R. Uluski

    The role of advanced distribution automation in the smart grid

  • M. Kezunovic

    Smart fault location for smart grids

    IEEE Trans. Smart Grid

    (2011)
  • M. Erol-Kantarci et al.

    Reliable overlay topology design for the smart microgrid network

    IEEE Netw.

    (2011)
  • W. Ling et al.

    Iec 61850 model expansion toward distributed fault localization, isolation, and supply restoration

    IEEE Trans. Power Deliv.

    (2014)
  • Y. Yan et al.

    Smart grid technologies: Communication technologies and standards

    IEEE Trans. Ind. Inform.

    (2011)
  • M. Sachdev et al.

    A laboratory for research and teaching of microprocessor-based power system protection

    IEEE Trans. Power Syst.

    (1996)
  • M. Kezunovic et al.

    The role of digital modeling and simulation in power engineering education

    IEEE Trans. Power Syst.

    (2004)
  • P.G. McLaren et al.

    Software models for relays

    IEEE Trans. Power Deliv.

    (2001)
  • J. Ren et al.

    Teaching protective relaying design and application using new modeling and simulation tools

    J. Energy Power Eng.

    (2012)
  • W.-J. Lee et al.

    A physical laboratory for protective relay education

    IEEE Trans. Educ.

    (2002)
  • M.G. Kanabar et al.

    Laboratory investigation of iec 61850-9-2-based busbar and distance relaying with corrective measure for sampled value loss/delay

    IEEE Trans. Power Deliv.

    (2011)
  • D. Montenegro, Dssim-pc, electrical distribution system simulator for pc. URL...
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