The study of “Electric Markets” within the field of Electrical Engineering is usually approached by computer simulations because any practical exercise is quite complex to implement. With the aim of improving student learning around this topic, a new subject called “Devising an Electric System” was formed following a CDIO approach. The subject has a duration of one academic year and is based entirely on laboratory work. The students are divided into three groups and each group has to work on a device that includes a solar PV generator and a pumping controlled drive, both connected to a three phase electric grid. Thus, the hardware in which the students deal with, includes mainly a laptop connected to a DSP, two power converters (one DC/AC that connects the PV generator to the grid, and another AC/AC that feeds the pump motor from the grid) current and voltage sensors and energy measurement devices. The process followed by the subject along the course begins with a short theoretical introduction and simulation studies where the students conceive and design control strategies, both for the solar PV generator (i.e. programing the “Maximum Power Point Tracking” MPPT) as well as for the pumping electric drive (i.e. following a V/f strategy or a vector control). It is continued by practical implementation of the simulated algorithms previously obtained, where the students implement and operate the systems until they get robust and well adjusted, and ready for the intermediate partial competitions among the three groups. In these competitions, they have to inject as much PV energy as possible to the grid and pump as much water as possible to a reservoir with the highest efficiency, for example. Once each group owns an electric generator and an electric consumption (load), they are ready to face the third and last part of the subject. Again the students follow a CDIO approach, but focused on “electric utility” business strategy. They will have to comply with the rules of the electric utility market by offering energy packages to be generated and consumed at a certain price. The price and volume of energy are determined by the point at which the supply and demand curves meet, according to the marginal pricing model. Considering this fixed price, the group that comes up with the best offers will be chosen as the winner. Based on the experience perceived after the first year of teaching this subject, the perception from the teachers and students was excellent. Although different comments will be discussed about the weaknesses and strengths of the subject, the main conclusion derived from the students’ evaluation was highly positive. Students have learnt the specific technological contents of the subject by “doing”. Moreover, having had good work atmosphere between students and teachers, students have improved their skills in team building, creativity and communications.
To our knowledge, this work constitutes the first experience that joins three different aspects in the field of Electrical Engineering, which are renewable generation, control of electric drives and electric markets, in the same subject and has followed a complete CDIO cycle.
Proceedings of the 12th International CDIO Conference, Turku, Finland, June 12-16 2016