The paper presents the simplest methods for preventing the occurrence of low energy quality. The problem of the quality of electric current was also discussed, indicating its defects. A scheme for a power failure tree was developed using the FTA method. The obtained results were compared and discussed.
Słowa kluczowe: uninterruptible power supply, power quality, supply voltage parameters.
W pracy przedstawiono najprostsze metody zapobiegania występowaniu niskiej jakości energii. Omówiono również problem jakości prądu elektrycznego, wskazując na jego wady. Opracowano schemat drzewa awarii zasilania korzystając z metody FTA. Uzyskane wyniki zostały porównane i omówione.
Keywords: bezprzerwowe zasilanie, jakość zasilania, parametry napięcia zasilania
Among the most important methods of hazard analysis and risk assessment, the authors applied the FTA method. The error tree method is a qualitative risk analysis method using logical tree structure, allowing to model the course of failure and then its analysis. In the FTA method, individual factors that can lead to an event and their potential effects are depicted in the socalled fault tree that shows the interdependencies between the potential main event and its causes. Identified factors (causes) plotted on the fault tree are interrelated and can be referred to as: specific failures (e.g. machines and devices), human errors (e.g. on the production line), first and second type errors, environmental conditions and other events that could lead to failure. In the 1990s, the use of FTA was started in the design of systems guaranteeing a high level of safety and reliability in the chemical, railway, IT and medical industries. It has also become a frequently used method in risk analysis and risk assessment alongside PHA and FMEA. Analysis of the FTA fault tree is therefore a graphical model of cause-and-effect relationships. The FTA scheme illustrates the causes whose effect is referred to as an uncertain event or risk. The result of the FTA analysis can be, for example, a logical tree showing the pressure tank crack scenario with highlighted errors of the first and second type. The first type of errors are production defects that appear while operating under design conditions. The second type of errors are errors of an element working in conditions for which the device was not intended. This is usually a mistake related to the wrong selection of an element for the process conditions. PHA (Preliminary Hazard Analysis) Preliminary Hazard Analysis (PHA) focuses on identifying any potential hazards and accidental events that can lead to a failure or accident. It is a non-standard method, based on knowledge available at the initi [...]
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