The electrical equipment used by electric traction locomotives to obtain electrical energy from the catenary is installed on the roof of the locomotive or motor car. The pantograph can be divided into two types: single-arm bow and double-arm bow. Both are composed of sliding plate, upper frame, lower arm rod (lower frame for double-arm bow), underframe, bow lifting spring, transmission cylinder, support insulator and other components. The diamond pantograph, also known as the diamond pantograph, was very common in the past, but was gradually eliminated due to high maintenance costs and easy to break the contact net in the event of a fault. In recent years, single-arm bows have been used.
The contact wire is in direct contact with the pantograph of the electric locomotive and friction occurs. In order to ensure reliable contact between the pantograph and the contact wire, without disconnection, and to ensure uniform wear of the pantograph, the contact wire is required to be fixed in position on the line according to technical requirements, that is, in positioning At the point, ensure that there is a certain offset between the contact line and the center of the pantograph skateboard of the electric locomotive, which is called the pull-out value.
The pull-out value is an important technical parameter in the operation of the catenary, and its value directly affects the safety of the pantograph. During operation, it was found that the pull-out value of the curve section exceeded the standard seriously. This is because the meteorological conditions, line parameters, locomotive and pantograph models and parameters, operation mode, and operation of the pantograph center line were not considered when setting the pull-out value. Dynamic changes under the influence of various factors such as speed. Based on this situation, it is necessary to analyze several main influencing factors such as operating speed, line parameters, and construction errors, and set the pull-out value reasonably to ensure a good flow of the locomotive.
The smoothness of the load current through the contact line and the contact surface of the pantograph sliding plate is related to the contact pressure, transition resistance and contact area between the sliding plate and the contact line, and depends on the interaction between the pantograph and the contact net.
In order to ensure the smooth flow of traction current, there must be a certain contact pressure between the pantograph and the contact wire. The actual contact pressure of the pantograph net consists of four parts: the pantograph lifting system exerts on the sliding plate to make the upward vertical force a static contact pressure (generally 70N or 90N); due to the difference in elasticity of the contact suspension itself, the contact line is receiving The pantograph will rise to different degrees under the action of lifting, so that the pantograph will vibrate up and down during operation, so that the pantograph will produce a dynamic contact pressure that is related to its own reduced mass; the pantograph is in operation An aerodynamic force that rapidly increases with the increase in speed generated by the action of air flow; the damping force generated by the joints of the pantograph during the process of raising and lowering the bow.
The pantograph-net contact pressure can intuitively reflect the contact situation between the pantograph sliding plate and the contact line. It must conform to the normal distribution law and fluctuate within a certain range. If it is too small, it will increase the offline rate; if it is too large, it will cause greater mechanical wear between the sliding plate and the contact line. In order to ensure the reliable current receiving quality of the pantograph, the reduced mass of the pantograph should be minimized and the elastic uniformity of the contact suspension should be increased. The quality and electromechanical properties of the skateboard have a great influence on the quality of the flow.
Finally, a model is used to test the train, and measure the strength and length of the bow according to EN50317. It is a waterproof UV sensor imported from Germany-UV-Arc. UV-Arc is a waterproof sensor with a threaded body (G3/4”), which will be used on trains to measure the strength and length of the bow according to en50317. This represents the quality of the contact between the pantograph and the catenary and allows the location of defects to be found on the wire rope within the rail network. The UV-Arc sensor is configured for this particular application. It contains a very sensitive photodiode and An additional fi lter suppresses the sensitivity of solar UVB. The time constant is adjusted to the typical arc length and the metal enclosure provides high electromagnetic compatibility safety.
