Abstract:

Electrical engineering, and in particular the fundamentals of electrical engineering, are considered to be very abstract because most phenomena within electrical systems are not directly accessible to the human senses. For this reason, they are often described mathematically. These two facts are very challenging, especially for beginners. As part of the learning process, learners construct their own explanation patterns that can logically explain the given problems. Such patterns are often correct for special cases and become incorrect when they are generalized. A light-emitting diode (LED) with a series resistor (here: pre-resistor) can be used as an example. This resistor limits the current of the LED and prevents it from being destroyed. Learners construct an explanation pattern in which they consider the position of the resistor to be important. If the resistor were placed behind the LED in another circuit, learners with this explanation pattern would incorrectly assume that the resistor has no effect on the current through the LED. These patterns are called preconceptions and are categorized as helpful and unhelpful. The described preconception is helpful for a pre-resistor and unhelpful for the general case.

The order of components is only one of the possibilities that can lead to unhelpful preconceptions. Learners often misunderstand cause (e.g. electric current through a resistor) and effect (e.g. the voltage drop across that resistor), or assume different functionalities based on different illustrations of a circuit. For this reason, it is essential to consciously address such preconceptions in the teaching process. This means, on the one hand, that such preconceptions must be identified and, on the other hand, that learners must be supported with appropriate exercises to reduce unhelpful preconceptions.

An important option practiced by the author is the use of small circuits built in class. Afterwards, the learners analyze the circuits by measuring currents and voltages. This option has the disadvantage that the different aspects have to be worked out indirectly by interpreting the measurements. Another approach is to use simulation tools. The spectrum of simulation tools ranges from tools developed more for professionals (e.g. LTspice) to learning tools (e.g. Yenka). They differ in their technical features as well as in their didactic concept. The didactic concept focuses on the visualization of current, voltage and in some cases power. This visualization may be useful for some preconceptions, or it may have no effect. It is also possible that the simulation tools emphasize unhelpful preconceptions.

The full article will begin with a brief description of the author's constructivist didactics of electrical engineering in order to present the framework of his research. Then, in the first main part of the article, some examples of preconceptions will be presented and the problem of their identification will be discussed. In the second main part of the article, individual didactic concepts of simulation tools will be described. The technical aspects of the tools will be left out for reasons of relevance. Based on this, the suitability of each didactic concept for reducing unhelpful or creating helpful preconceptions will be discussed. Finally, a catalogue of requirements for simulation tools in education will be defined, which can be used for the selection of simulation tools as well as for the design of new simulation tools.

Keywords:

Preconceptions, fundamentals of electrical engineering, didactics.