Research On Energy Efficient Evaluation And Fault Diagnosis Of Cold End Of Direct Air-cooling Units

Direct air-cooling unit has been rapid development in rich coal and water-poor areas of China’s. This paper established evaluation model of energy efficiency of direct air cooling unit to achieve evaluation of energy efficiency on cold end systems in real-time. If the results of the evaluation were not an ideal situation, the results can do optimize of run-adjustable parameters and maintain fault diagnosis by rated class to improve the energy efficiency and safety of the cold end system.Energy efficiency evaluation model started with the AHP-F evaluation method. The levels of energy efficiency are excellent, good, fair, needs to be improved, the need for rectification. When the cold-end system performance evaluation results needs to be improved, the cold end system should be optimized to adjust. Optimization target is the optimal back-pressure. This paper established the cold end system variable condition mathematical model, combined with backpressure correction curve of direct air-cooled power plant and wind power fleet consumption, can obtain the way of determining the optimal back-pressure and optimal wind speed under varying operating conditions. Optimal back-pressure is calculated as the reference value to get space saving after the cold end system optimization.When the results of evaluating on cold end system is required to rectify, fault diagnosis task is triggered. Cold end system performance degradation fault top event is a vacuum down. It may be caused by the fan system failure, seal system failure, vacuum system failure, the main condensate system failures, other equipment failures caused by air-cooled condenser. Aiming at 13 faults, combined with FMEA, FTA analysis, failure mode analysis,the fault symptom analysis, fault analysis and fault repair measures carried out, established a very complete cold-end system knowledge base. On this basis, the fuzzy pattern recognition is used in troubleshooting of cold end system, the study showed that high diagnostic accuracy and obviously separation.