Creating Power Engineering Laboratory Experiences For Distance Education Students

A virtual laboratory for outreach (or off-campus) electrical power engineering students using the personal edition of PSCAD/EMTDC, a time domain electromagnetic transients program, is presented. The lab experience starts out with a video tour of the lab the on-campus students will use, including a description of the equipment in the lab. Five lab experiments covering: three phase measurements, three phase transformers, synchronous generators, and load flow studies are implemented. The off-campus students perform the same lab exercises as their on-campus classmates, record the same types of data, and provide the same computations for their reports. The off-campus students start with data files providing the basic building blocks they need to implement the lab, including metering functions that provide the same outputs available in the lab. The simulation results and experimental results were both compared and verified to ensure that the results will be similar. Introduction Every electrical engineer will likely encounter a certain range of energy topics, such as household and commercial distribution and wiring, power quality problems with harmonics, transformers, small dc motors, dc/dc conversion, and switch mode power supplies. A required first course in power engineering is designed to address these topics at the junior level [1]. Also included are topics that form a foundation in alternating current phenomena and analysis for those students who intend to study further. A laboratory requirement emphasizes applications of these topics. The EE curriculum requires that each student take a second course (at the senior level) in at least three of five fundamental areas: analog electronics, power and energy, electromagnetism, digital electronics, and systems (communication and controls) . In the second power engineering course, the following topics for steady state, three phase, balanced power systems are taught: foundations of three-phase systems, three phase transformers, transmission systems, power flow, and generation [1]. This second course serves those students who have energy as a primary or secondary interest. There is a half-credit laboratory requirement as part of this course. However, this course is also the first course taken by distance education students who are planning to pursue graduate degrees but were not able to take a course on three phase energy systems as undergraduates. Since this half credit laboratory is a required component of the course, the distance students also need to complete laboratory exercises. One option is to assign an oncampus lab partner for each off-campus student. However, the delivery of the course materials P ge 10368.1 Proceedings of the 2005 American Society for Engineering Education Annual Conference & Exposition Copyright 2005, American Society for Engineering Education places the off-campus students two weeks behind their on-campus classmates, which creates timing problems for the interactions between the students. This is especially true around the time periods for fall and spring breaks and at the end of the semester when the on-campus students complete the course prior to their outreach counterparts. This paper presents experiences using the personal edition of PSCAD/EMTDC [2], a time domain electromagnetic transients program to develop virtual lab. The lab experience starts out with a video tour of the lab the on-campus students will use including a description of the equipment. Five lab experiments covering: three phase measurements, three phase transformers, synchronous generators, and load flow study are implemented. The off-campus students perform the same lab exercises as their on-campus classmates, record the same types of data, and provide the same computations for their reports. The off-campus students are provided with simulation models containing basic building blocks they need to implement the lab, including metering functions that provide the same outputs available in the lab. The simulation results and experimental results were both compared and verified to ensure that the results will be similar. The virtual labs provide an excellent learning tool for outreach students to match the labs performed on campus and introduce tools that will be used in later graduate courses. Lab Experiences in a Power and Energy Curriculum: The structure of a good power and energy curriculum should meet three requirements: 1. Provide the background in fundamentals of power engineering, 2. Introduce more advanced topics to prepare students for employment as electrical engineers, 3. Produce student interest in the field of power engineering. Employers have always been clear in their expectation that any electrical engineering graduates that they hire should possess a strong foundation in a broad range of fundamentals. In the curriculum at hand at the University of Idaho (UI), these fundamentals are defined within five areas of study: analog electronics, power and energy, electromagnetics, digital electronics, and systems. In this fivefold structure, the Electrical and Computer Engineering (ECE) Department organizes its faculty expertise. At the junior level, students must take one course and one lab in each of the five areas. This requirement provides an introduction and a foundation of common topics across the available breadth of electrical engineering practice and generates student interest for chosing advanced topics. At the senior level, the ECE Department requires that each student take at least one course in three of the five areas of study. Most, but not all, areas have a senior-level lab requirement. This structure provides a strong breadth in the fundamental topics that the department offers and meets the employers requirement. With the emphasis on balancing breadth and depth, one would think that there would be only two categories: those students who get only breadth and those who want more depth. However, this is not the case. In fact, defining three categories of student interest leads to a new and perhaps more effective curriculum. The three categories of students can be defined as follows. 1. Students who take a power and energy course solely to meet breadth requirements. These students appear in only the one junior-level power and energy course, taking all their other courses in other areas. There is but this one opportunity to provide these students with an introduction and appropriate breadth of study in power and energy. The junior-level power course also generates student interest for further study in the power area. P ge 10368.2 Proceedings of the 2005 American Society for Engineering Education Annual Conference & Exposition Copyright 2005, American Society for Engineering Education 2. Students who recognize a need for more skill in using power and energy. These students intend to specialize in another area, so extensive depth of study is not practical. However, they recognize the importance of being able to understand energy topics better and to relate more effectively to those who provide energy to them. 3. Students who want depth of study in power and energy topics. These students expect to seek and gain employment within industries that expect a significant degree of specialized preparation. For example, these include the electric utilities, manufacturing and process industries, and certain government agencies. These students want the greatest depth that limited time and resources can provide. Their employers expect it and say so. This paper concentrates on students in the second and third categories, a group that has already taken the first course on power and energy and is ready for the second energy systems course. The second course in power serves those students who have energy as a primary or secondary interest. There is a half-credit senior-level laboratory requirement as part of this course. However, this course is also the first course taken by distance education (a.k.a outreach or off campus) students who are planning to pursue graduate degrees but were not able to take a course on three phase energy systems as undergraduates. Since this half credit laboratory is a required component of the course, the distance students also should complete laboratory exercises. Options available for off campus students: Several options were sought to provide equal learning opportunity for the outreach and oncampus students. Option 1: No lab at all. This will not keep the engineering outreach program at UI on par with the on campus program. Even though both on campus and outreach students receive the same amount of lecture material, the outreach students will be deprived of the opportunity in getting hands on lab experience. So this option does not help to fortify UI outreach program. Option 2: The on-campus students have the opportunity to conduct experiments, record experimental data, perform calculations and write a lab report on the conducted experiment. The data recorded by one of the groups of on-campus students is then sent to the outreach students who then write their own lab reports based on this data. This provides some lab experience, but it can’t provide the lab experience and the physical understanding that can be associated with labs. Option 3: Assign each outreach student an on campus lab partner. This approach is similar to option 2, except that each of the outreach students can discuss the lab in more detail with the their lab partner to gain a somewhat better understanding of the material. This interaction will also help the on campus students understand the material more fully. However, scheduling is a problem with this approach. The outreach students are generally two weeks behind their on campus counterparts due to the time for shipping the tapes/DVO’s of the lectures to them. As a result, by the time the outreach students have viewed the lectures containing the lab material, the on campus students are on the next topic and the la