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Contact force between a pantograph and catenary is one of the most important indices for evaluating the contact performance of the pantograph-catenary system. Hence, some contact force measuring methods have been developed. However, currently used measurement methods have some problems. Firstly, the installation of sensors in a panhead could affect the dynamic characteristics of the pantograph. Secondly, they need data transmitting equipment, because built-in sensors are set under high-voltage condition. Thirdly, some kinds of pantographs cannot be equipped with sensors in a panhead because of structural restriction. To eliminate these problems, the authors have developed a new contact force measuring method by using image processing sensors mounted on the rooftop of a train.

In this study, the authors investigated the mechanisms behind undulating wear formation by examining the sliding surfaces of overhead conductor rails and the dynamic characteristics of pantographs used on commercial lines. Undulating wear can result in contact loss between the line and the pantograph and lead to more frequent arcing, one of the main sources of extreme conductor rail and contact strip wear. The authors found that periodic unevenness is formed by mechanical wear due to the dynamic characteristics of a pantograph, particularly its anti-resonance. Arcs due to contact loss often occur along the undulating conductor rail when the wear amplitude increases such that the pantograph cannot keep contact with the rail. The authors also determined that the interval between pantograph heads is related to the wavelength of extreme undulating wear.

The aerodynamic characteristics of pantographs for high-speed trains are a critical factor towards steady current collection. We introduce a new panhead in which air is taken in at the leading edge and ejected around the trailing edge to control lift force. The aerodynamic characteristics of this panhead are estimated using a numerical simulation and a wind tunnel experiment, with the results showing that the system is effective in controlling lift force.

This paper provides a means of flow control for rail pantographs by using air intakes and outlets to improve aerodynamic characteristics. The developed panhead allows to air to enter the pantograph at the leading edge of the device and eject from the trailing edge. This design allows for the control of lift force and so improves the interface between the pantograph and wire. Numerical simulation methods are used in conjunction with wind tunnel testing to evaluate the proposed design for pantograph aerodynamics. One issue that researchers had to contend with in this situation was that of sufficient volume of air for jet ejection, the outlet of which is located near to the trailing edge and is connected to a stagnation point by an air tube.