Abstract:

The Covid-19 pandemic has exposed engineering education to a number of problems related to laboratory practice, which is very important for the training of qualified engineers. The need for isolation during the pandemic made it very difficult and even in some cases impossible to conduct laboratory exercises in a number of engineering disciplines in the presence of students. However, without laboratory practice, engineering students find it difficult to develop the necessary problem-solving skills at different professional levels, which usually involves understanding and applying a variety of scientific principles and engineering techniques. The main problems and challenges are related to basic engineering disciplines such as electrical engineering, where the exercises are conducted in laboratories with relevant research models and specialized measuring equipment, which can hardly be conducted online or replaced by simulations.

This article presents the experience of lecturers from the Faculty of Physics and Technology at Plovdiv University in developing a laboratory exercise in the discipline "Electrical Engineering" through a remotely controlled stand for research of AC electric motor and its implementation in training. The stand control is based on the ESP8622 wireless WI-FI module. The Message Queuing Telemetry Transport (MQTT) protocol is used to communicate and control the ESP8622 module, which provides remote access to the AC motor. This communication protocol allows various devices equipped with microcontrollers to be controlled via the Internet, regardless of the operating system of the computer control system.

A methodology for remote laboratory exercises on an AC electric motor using virtual instruments is presented. Virtual tools allow for smooth phase control of the AC motor and the study and analysis of various operating characteristics by monitoring the Zero Crossing Detector. In this way, students can explore and understand in real time, without being physically present in the electrical engineering laboratory, what the Zero Crossing Detector is and how smoothly the power of an AC motor can be controlled smoothly.

The proposed learning approach was assessed by students through a survey. The survey showed that students perceive the use and application of technologies for remote laboratory exercises and find them good enough learning resources.

Keywords:

e-learning, engineering student, electrical engineering, ESP8622.