Stability Of Current Collection And Control For High-Speed Locomotive

It is general trend to develop high-speed railway in order to modernize the railway industry, where the electric locomotive play the most important role. An electric locomotive collects energy from the catenary, in which good characteristic of pantograph and catenary affects the performance of current collection. With the running speed increased, the dynamical contacting turns more and more complex. How to ensure the stable current collection is one of the most important research tasks. The main work of this dissertation is summarized as follows:1 The pantograph is simplified into a single degree of freedom non-dimensional dynamical system, which shows to be a Mathieu equation. The stable current boundary formula is derived via perturbation method and the characteristic of current collection is confirmed under variable running speed.2 It is the first time to propose Lyapunov exponent in analyzing high speed pantograph-catenary stability. The Lyapunov exponent of actual pantograph-catenary system is calculated and a quantitative system stability analysis is performed while design variables changed, and then the best and bad running speed is put forward for the system.3 After a 3-degree-of-freedom model for sensitivity analysis is set up, various sensitivity analyses of the pantograph-catenary system are performed in time domain. Sensitivity is evaluated for the contact force at various speeds. The result shows that (1) pan-head mass m1 has maximal contact force sensitivity value in the all of design variables, pan-head damp c1 has the second one, pan-head stiffness k1 has the third one. (2) the sensitivity analysis of contact force for pantograph-catenary shows that pan-head mass m1 has more impact on sensitivity than the other masses, while mass m2 has the smallest sensitivity. The Pan-head stiffness k1 has relatively bigger sensitivity value among whole stiffness, and bigger sensitivity value alternates between upper arm stiffness k2 and lower arm stiffness k3. The damping has the same effects with stiffness.4 In order to examine the static and dynamic behavior of pantograph-catenary system and optimize the pantograph, a special test-bad is established in this dissertation. The pantograph-head stiffness, mass and damping, frame stiffness, mass and damp have been tested. Relation between driving pantograph force and pantograph-height are also obtained, the pantograph has three main frequencies, which are 0.94, 2.5 and 4.17Hz.