# Power Quality Impact and Its Assessment: A Review and a Survey of Lithuanian Industrial Companies
## 5 Discussion  
### Research Gaps  
PQ impact is a broad and relevant topic not only for science but also for practice. Such studies are expected to help solve many practical problems necessary to ensure smooth economic, environmental and social development, in particular situational awareness, development of predictive maintenance systems, planning of PQ mitigation measures, power system resilience assessment and enhancement, creation of a full-fledged legal mechanism for PQ regulation, etc. The benefits, of course, can be more than just pragmatic--the search for new knowledge, the systemization of existing knowledge, as well as its dissemination are among the main tasks of science in any field. The findings must not only be presented in the scientific literature but also transferred to standards, guidelines and other relevant documents, and the process is moving towards that. For example, it is necessary to mention IEC TR 63222-100:2023 [116], a technical report published by IEC that focuses on the impacts of PQ issues on electric equipment and power systems by collecting relevant information from CIGRE reports, case studies, research findings, etc., and it is hoped that the content will help users, equipment manufacturers and network operators make rational investments and actively cooperate to take specific measures for PQ improvement. Another relevant document, which complements the information given in Section 2.3, is IEC TS 60601-4-2:2024 [117], a technical specification that focuses on medical electric equipment and medical electrical systems which may fail to perform their functions because of a lack of immunity to electromagnetic disturbances. However, both documents are not freely accessible and thus cannot be reviewed in detail. Although the subject of PQ is gradually gaining attention, the current level of research on the topic of PQ impact and its assessment is only in its early stage and far from sufficient. Also, it is not always possible to conclude whether the results of older studies are still valid. Based on the information given in Sections 2 and 3, a framework for further research avenues on the subject of PQ impact is presented in Table 30. However, it should be noted that an understanding of what needs to be carried out on a topic of PQ impact is only a small step forward. There is a serious lack of technical capabilities for such studies: not everything can be simulated using software tools or studied in laboratories (which in turn also requires a complex and expensive set-up), whereas obtaining the results in real conditions requires long and consistent work in collecting statistics (e.g., the primary causes of grid failures, PQ event rate and their parameter distributions, etc.) and will not be fast enough simply due to the insufficient probability of occurrence of phenomena, which cannot be simply overcome with the massive installation of measuring devices due to such reasons as their functionality limitations, processing of the generated large amount of PQ data will require proper information and communication technologies (in contrast to the present, when in the absolute majority of cases PQ data are collected and analyzed manually), as well as the high cost, which will be possible to somewhat minimize when it will be feasible to solve PQ monitor allocation optimization problems in practice [1; 8].