Experimental campaign on a servo-actuated pantograph

Many interesting technical problems arise from the development of high speed trains current collection is one of the more important. The dynamic behaviour of a pantograph-catenary system make the electrical contact between the catenary and the contact-shoe unreliable. An insufficient quality of current collection causes a lot of negative consequences such as: insufficient current pick up, excessive wear of contact shoes and wires, power and control electronics malfunction, high EMI. Many Researchers have investigated the problem of optimum current pick up and many different solutions have been proposed in the past years. Since 1993 the Researchers of University of Florence have proposed the idea of a servo-actuated pantograph. The purpose of these studies was the development of a system including sensors and actuators able to regulate the value of relevant variables, such as contact force, at an optimum level researchers of Italian Railways found the proposal of a servo-actuated pantograph very interesting so the two groups began to co-operate. After the development of simulation models to evaluate performance and robustness of some control techniques for a servo-actuated pantograph, the authors arranged an experimental campaign in order to verify the results of simulations and to develop a first prototype of servo-actuated pantograph. This paper describes some simulation and experimental results obtained during the campaign which is currently going on.