Steering system for a rail vehicle locomotive is one of the key sub-systems that improves the vehicle curving performance with respect to traditional rolling stock that relies on natural curving feature of wheelset. During the last decades, various configurations of passive, semi-active and active steering systems attempted to optimize the system performance with different advantages and disadvantages. The aim of present work is a comparative assessment of suitable steering systems among available solutions for a Co-Co locomotive from curving performance improvement and maintenance cost reduction points of view, by reducing wear in wheel-rail contact. In addition, this achievement will address the traction maneuvers as well, since traction is usually demanded on curved track for locomotives. This thesis is mainly focused on both passive and active steering approaches consisting mechanical linkages that induce some profundity of changes in traditional design of the bogie and consequently capture distinct levels of improvement in performance. Moreover, an innovative combination of passive and active steering arm and the correspondence control strategy is defined in this work that obtains a higher performance enhancement with respect to previous models. Simulation results for various curving conditions reveals a significant wheel-rail wear reduction and curving improvement. Finally, traction and stability issues are analyzed, and the reliability of the system is ensured.various configurations of passive, semi-active and active steering systems attempted to optimize the system performance with different advantages and disadvantages. The aim of present work is a comparative assessment of suitable steering systems among available solutions for a Co-Co locomotive from curving performance improvement and maintenance cost reduction points of view, by reducing wear in wheel-rail contact. In addition, this achievement will address the traction maneuvers as well, since traction is usually demanded on curved track for locomotives. This thesis is mainly focused on both passive and active steering approaches consisting mechanical linkages that induce some profundity of changes in traditional design of the bogie and consequently capture distinct levels of improvement in performance. Moreover, an innovative combination of passive and active steering arm and the correspondence control strategy is defined in this work that obtains a higher performance enhancement with respect to previous models. Simulation results for various curving conditions reveals a significant wheel-rail wear reduction and curving improvement. Finally, traction and stability issues are analyzed, and the reliability of the system is ensured.
Il sistema di sterzatura per una locomotiva per convogli ferroviari è uno dei sottosistemi chiave che migliora le prestazioni del veicolo in curva rispetto al materiale rotabile tradizionale che fa affidamento alla conicità delle ruote della sala. Negli ultimi decenni, diverse configurazioni di sistemi di sterzatura passivi, semi-attivi e attivi sono stati ideati al fine ottimizzare le prestazioni del sistema con diversi vantaggi e svantaggi. L'obiettivo del presente lavoro è una valutazione comparativa di diversi sistemi di sterzatura per una locomotiva Co-Co per il miglioramento delle prestazioni in curva la consegente riduzione dei costi di manutenzione, riducendo l'usura dovuta al contatto ruota-rotaia. Inoltre, questo aspetto verrà analizzato considerando anche le manovre di trazione, poiché per le locomotive è prevista anche la situazione di trazione su tracciato curvilineo. Questa tesi si concentra principalmente sugli approcci di sterzatura sia passivi che attivi ottenuti attraverso collegamenti meccanici che modificano profondamente il design tradizionale del carrello e, conseguentemente, consentono di ottenere un elevato miglioramento delle prestazioni. Inoltre, la combinazione innovativa di un sistema meccanico di sterzatura passivo con un sistema attivo consente di ottenere ulteriori miglioramenti rispetto ai modelli precedenti. L’efficacia dei sistemi è dimostrata attraverso la simulazione numerica di diverse curve che dimostrano una significativa riduzione dell'usura della ruota e della rotaia ruota e un miglioramento della sterzatura. Infine, vengono analizzati la stabilità del sistema garantendo che il sistema proposto non comprometta la sicurezza di marcia del veicolo.
Active steering for 3-axle bogies in railway locomotives
HEYDARI, SAREH
2017/2018
Abstract
Steering system for a rail vehicle locomotive is one of the key sub-systems that improves the vehicle curving performance with respect to traditional rolling stock that relies on natural curving feature of wheelset. During the last decades, various configurations of passive, semi-active and active steering systems attempted to optimize the system performance with different advantages and disadvantages. The aim of present work is a comparative assessment of suitable steering systems among available solutions for a Co-Co locomotive from curving performance improvement and maintenance cost reduction points of view, by reducing wear in wheel-rail contact. In addition, this achievement will address the traction maneuvers as well, since traction is usually demanded on curved track for locomotives. This thesis is mainly focused on both passive and active steering approaches consisting mechanical linkages that induce some profundity of changes in traditional design of the bogie and consequently capture distinct levels of improvement in performance. Moreover, an innovative combination of passive and active steering arm and the correspondence control strategy is defined in this work that obtains a higher performance enhancement with respect to previous models. Simulation results for various curving conditions reveals a significant wheel-rail wear reduction and curving improvement. Finally, traction and stability issues are analyzed, and the reliability of the system is ensured.various configurations of passive, semi-active and active steering systems attempted to optimize the system performance with different advantages and disadvantages. The aim of present work is a comparative assessment of suitable steering systems among available solutions for a Co-Co locomotive from curving performance improvement and maintenance cost reduction points of view, by reducing wear in wheel-rail contact. In addition, this achievement will address the traction maneuvers as well, since traction is usually demanded on curved track for locomotives. This thesis is mainly focused on both passive and active steering approaches consisting mechanical linkages that induce some profundity of changes in traditional design of the bogie and consequently capture distinct levels of improvement in performance. Moreover, an innovative combination of passive and active steering arm and the correspondence control strategy is defined in this work that obtains a higher performance enhancement with respect to previous models. Simulation results for various curving conditions reveals a significant wheel-rail wear reduction and curving improvement. Finally, traction and stability issues are analyzed, and the reliability of the system is ensured.| File | Dimensione | Formato | |
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https://hdl.handle.net/10589/139884