The pantograph lift measurement method in overhead catenary system

Condition monitoring technology has advanced remarkably in recent years in various areas, including railways. Since the overhead catenary system and the pantograph in railway does not have enough redundancy, failures of the overhead catenary system or the pantograph will result in long downtime in railway operations. For preventing such failures efficiently, it is effective to apply condition monitoring methods to detect the pantograph failure on the overhead catenary system. To Achieve stable current collection, although the lift characteristic of the pantograph must be maintained within an appropriate range, the monitoring method of lift of pantograph in actual use has been not established so far. Therefore, the authors developed a method to measure the lift of pantographs with sensors on the overhead catenary system. According to this method, the lift is obtained from the sum of hanger forces and vertical components of the tensile force of contact wire. However, this method has some problems to solve in terms of measurement error and easiness of implementation. Therefore, in this paper, the authors focus on the wave equation for each wire of the overhead catenary system to propose new four measurement methods of the pantograph lift. The proposed methods will solve the problems of the previous methods. The methods are verified using dynamic simulation of the overhead catenary system and the pantograph. It also reports that the proposed method is effective even when two pantographs pass continuously.