Faults Analysis Of The Power Supply System And Safety Assessment In A Large Plaza

This dissertation mainly focuses on the frequent occurrences of power-break of the power supply system in some large commercial plazas in China cities, which have surely resulted a lot of losses in properties and human accidents. By making a lot of analysis of the faults of the power supply system, the causes of the accidents and the synthetic safety assessment by taking the power supply system and accidents in Changsha Friendship Shop were conducted as a typical example.Based on the research achievements in reliability of power supply system in the architectures and in safety assessment of the commercial plazas, the investigation on failure accidents and assessing system were done and the chief research results are as follows.According to the in-situ investigation of the conditions of the power supply system in Changsha Friendship Shop, the possible failures of the key devices including vacuum circuit breakers, cross-linking cables, dry mode transformers and UPS (Uninterruptible Power System) were analyzed, and the modes, effects and causes of their failures were discussed by means of ETA (Event Tree Analysis), CEAD (Cause and Effect Analysis Diagram) and FMEA (Failure Modes and Effects Analysis). Accordingly, the countermeasures for promoting their operational reliability were put forward.On the basis of probes and case analysis of existing safety problems after power-break of a shop, the systematic research on safety problems concerning with lives, commodities, devices and fire fighting was done, and the major and minor causes of all kinds of accidents were analyzed by. means of safety system engineering such as FTA (Fault Tree Analysis), CEAD, AHP (Analytic Hierarchy Process) and EBS (expert-brain-storm). Based on which safety management measures then be set up.The safety assessment index system for a large commercial plaza was established, and the weights of all of the indexes were ascertained using EBS and AHP. In addition, the method of the synthetic safety assessment which can ascertain a commercial plaza safety level was selected, making use of fuzzy mathematical synthetic safety assessment, safety check lists and EBS. Based on which, for the first time, the complete safety assessment system for a large bazaar was put forward.The dissertation is based on the power supply system and accidents in Changsha Friendship Shop, and the research has been given full and complete considerations upon which it is confirmed to be typical, comparative and demonstrative. The results of the research provide theoretical methods of safety management and supervision for other similar commercial shops. Therefore, they can be widely used and are valuable.