The paper presents a simulation model of the three fi nal spans and one 110/35/10 kV/kV/ kV distribution transformer substation (TS) bay. In order to demonstrate the insulation coordination procedure to students, we used this model to provide simulations of backfl ash and propagation of travelling waves to substation components. For this purpose, we used ATP-EMTP (Alternative Transients Program) software, which, owing to its user-friendly graphical user interface, can be effectively used for both scientifi c and educational purposes. Aiming for the modernisation of the Insulation Coordination curriculum, we are proposing modifi ed problem-based learning which combines a classical approach with true problem-based learning (PBL). The pedagogical method and ATP-EMTP simulation model presented in this paper are primarily focused on undergraduate students (the fouryear programme), but can also be appropriate at higher levels of education.Teaching insulation coordination to students of electrical power engineering is a serious task as the phenomena studied are complex and models describing them are very computationally demanding. 1 Earlier insulation coordination curricula relied primarily on the analytical approach to phenomena (Bergeron's method, transmission and refl ection of waves, Bewley's diagram) and also involved high requirements in respect of knowledge of mathematics. Hence students primarily focused on this aspect, whereas the nature of the phenomena mostly remained obscured. Computers were not used as a teaching aid in those days, and phenomena were studied separately, without aiming at their unifi cation into an overall insulation coordination procedure. The modifi ed method of problem-oriented learning in the Insulation Coordination courseBearing in mind the above-mentioned shortcomings referring to education in the fi eld of electrical power engineering, and the Insulation Coordination course in particular, the authors decided to modernize the course. As part of this approach the ATP-EMTP software tool has been introduced into our teaching. Globally, generalpurpose EMTP software tools are the most commonly used software tools employed for the analysis of transient processes in power system networks. 2,3 The user-friendly graphical interface ATPDraw enabled application of the ATP software tool not only in the research fi eld but also in education.At the Technical Faculty in Čačak, Republic of Serbia, the Insulation Coordination course is studied in the third year of the four-year BEng power engineering programme, this being the only course in this scientifi c fi eld. Students are not expected to acquire theoretical background in one course and to learn how to solve practical examples in another course. A 'Collection of Problems' were published. 4 In Ref. 4, all examples are of the so-called closed type. Such a closed problem is solved by using the linear-solving technique. 5 There is a unique solution for the given parameters. Two such illustrative examples are available at www.tfc.kg.ac.rs/ download/sto...

This work presents the use of the modern software tool Alternative Transients Program (ATP) in the teaching of power engineering, within the course Computer Aided Engineering. A simulation model is presented through which it is possible to analyse the effects of distributed generators (DG) on the operation of a distribution network in both a steady and a transient state, with the objective of fulfilling the conditions for connection. This problem was selected not only because it allows students to gain proper insight into the phenomena within a distribution network with a connected distributed generator, but also because it has been shown that the problem of educating engineers is often a constraining factor for implementing distributed generation (DG). It is shown that by using the software tool ATP-EMTP, very complex phenomena in large networks can be studied without great difficulty or the need for analytical methods. The problem-based learning (PBL) method was applied.Distributed generation (DG) is an electric power source connected directly to the distribution network. The current level of development in society could not even be imagined without this relatively new concept, the benefits of which are well known. 1 Unfortunately, the development of distributed generation in Serbia, as well as in the other Southeast European countries, is not at a satisfactory level. The reasons are of a political, legislative, technical and economic nature, but a constraining factor for Serbia in particular is also the problem of educating the engineers who are to realize this concept. Due to inadequate education, they resist the implementation of DG. 2 Because of this, during the past several years, additional courses on DG have been added to the curriculum in the faculties of electrical engineering, but they cover the principles of operation, energy potentials, exploitation, designing and economy of DG, and not the negative effect of DG on a distribution network. Namely, it is well known that DG can cause significant technical problems in the operation of an existing distribution network. The main problems are the effects on the voltage profile, load flow, short-circuit currents, loading capability, operation and settings of relay protection equipment, voltage regulation, unintentional islanding, loss of synchronism, and automatic reconnection. Because of this, standards in the USA, 3 technical guidelines in Serbia, 4 and the wider