Multi Project Fault Diagnosis Of Elevator Frequency Converyer

With the development of modern society,more and more high-rise buildings are being built,and elevators play an important role in our daily life.In China,there are currently 4.1 millions of elevators with a total usage of about 2 billion times daily.The elevator safety is highly valued by the government.Relevant laws and regulations for special equipment are improved gradually and the institutional settings are more and more completed.With the fast growth of the elevator industry,higher requirements are raised for elevator inspection.Frequency converters are the ideal solutions for AC drives in elevators.In this thesis,the diagnosis schemes of the frequency converter malfunctions that result in a less comfortable and safe ride are studied.Feasible programs of elevator frequency converter inspection are provided for the inspection and maintenance of elevators.Firstly,the structural principles and features of elevators are introduced briefly.The methods and equipment used for faulty signal collection are explained to provide a background for the following studies.Secondly,the diagnosis schemes of the common elevator frequency converter malfunctions are analyzed in details with reference to the published domestic and international studies on elevator frequency converter.Several diagnosis schemes are proposed for the faults in IGBT open circuits,the speed sensor,the current sensor and the Aluminum electrolytic capacitor of the frequency convertors.Finally,based on this study,inverter speed control and balance factor quick detection are proposed for the optimization of elevator frequency convertors,providing feasible and effective solutions to improve the comfortability and balance factor detection of elevators.