A Review of Circular Economy Research for Electric Motors and the Role of Industry 4.0 Technologies

Abstract

The market for electric motors is experiencing a step-growth due to their adoption across a range of industrial sectors. This increased demand also highlights the importance of end-of-life management of electric motors and a requirement for appropriate strategies for the high value materials embedded in them. This paper aims to offer a holistic view on the circular economy research for electric motors and the role of Industry 4.0 technologies by presenting the state-of-the-art available in literature and comparing it with the industrial perspective. The literature review revealed the absence of a methodology for selecting the best end-of-life scenario for industrial electric motors. Recycling, which is an end-of-product-life strategy, was found to be the key focus area of research. Reuse, which is a better strategy in terms of waste hierarchy, was the least researched area due to lack of information about the condition and availability of returned products. In order to capture the current landscape within the UK for the repair, remanufacture and recycling of electrical machines, a structured survey of UK based companies was conducted. The survey revealed that nearly half of the companies do not undertake any repair strategies for electrical machine components; however, there was an aspiration from the respondents to migrate their companies towards more sustainable activities. The industry survey and the review of existing literature led to the identification of research trends, challenges and recommendations for future research.

A framework of digital technologies for the circular economy: Digital functions and mechanisms

“…For example, computer algorithms can decide whether to repair, recycle, or discard items based on the results from examining the returned product for scratches and defects, or detecting different materials in wastes (Turner et al, 2020; Zhang et al, 2019). Another application of detection is to identify abnormal process behaviours through monitoring, making it possible to stabilize performances (Ingemarsdotter et al, 2021; Tiwari et al, 2021).…”

The Relationship between Circular Economy, Industry 4.0 and Supply Chain Performance: A Combined ISM/Fuzzy MICMAC Approach

“…According to Rajput [25], the CE integration with I4.0 is a way to achieve sustainability, as it reduces barriers such as lack of information regarding the life cycle of products and uncertainty about the return on investments [26]. For example, as Tiwari [8] (p. 2) stated, "the advent and adoption of digital technologies based on the principles of Industry 4.0 may help to overcome the barriers to the adoption of CE". In other words, if organisations want to maintain and strengthen their competitive potential, they need to embrace technological and environmental changes together [12].…”

“…Previous research has assessed the relationship between these themes. For example, some researchers have linked the CE to I4.0 [7,8], while others have linked, separately, the implementation of I4.0 or the CE to SC performance [1,2,[9][10][11]. However, a systematic analysis from the perspective of experts concerning the relationship between these three topics is still missing.…”

Generalized Differential Mathematical Model in Stator Reference Frame for PMSM and VRSM Simulation

“…Furthermore, considering their reliability in the current trend of growing circular economy (Tiwari, 2021;Leitner, 2020;Nuno, 2019), it is also of interest to reintegrate existing functional PMSMs from outdated or otherwise faulty devices in new or existing equipment while implementing better control approaches with benefits in power efficiency and Electro-Magnetic Compatibility (EMC) compliance (e.g., refurbished/upgraded spare components).…”