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Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Abstract-This paper describes the development of a solid-state fault current limiting and interrupting device (FCLID) suitable for low-voltage distribution networks. The main components of the FCLID are a bidirectional semiconductor switch that can disrupt the short-circuit current, and a voltage clamping element that helps to control the current and absorb the inductive energy stored in the network during current interruption. Using a hysteresis-type control algorithm, the short-circuit current can be constrained according to a predefined profile. Insulated-gate bipolar transistors and diodes are used to construct the semiconductor switch. Varistors are used as the voltage clamping element. An effective method is adopted to improve the current sharing between parallel varistors in order to provide the required capability of energy absorption. An overall protection scheme for the FCLID is described. A prototype FCLID for 230-V single-phase, or 400-V three-phase, applications is developed and tested. Analyses and experiments are carried out to define the stresses that the main components in the FCLID are subject to. The results show that the developed prototype is capable of limiting a 3-kA prospective short-circuit current to 120 A for a period of 0.8 s, without exceeding the thermal limits of the chosen switches and varistors.

This paper aims to highlight the importance of considering students' perceptions of and approaches to undergraduate engineering education. Whilst considering techniques to maximise the retention of engineering students, it is also posited that understanding how students perceive their learning contexts at university is vital. It is also essential that we understand how these perceptions influence students' approaches to their studies. This paper builds on existing research which takes a discipline focus to a discussion of the relationships linking quality of learning with generic research into approaches and perceptions of teaching and learning. It discusses an ongoing research project which is making use of a mixed methods research platform to investigate the complex nature of students' perceptions and approaches. It is presented as a valuable methodology for adoption by engineering education researchers.The research is based on an exploratory sequential mixed methods design where the qualitative data is dominant. Initial analysis of the data collected during the pilot phase, supported by relevant literature, has been used to identify areas of the learning context which appear to influence students' approaches to the engineering modules involved in the study. Some of the emerging themes are discussed in this paper with consideration for the impact on the teaching of engineering.

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