Speed stiffness characteristics of electro-hydro-mechanical system

Speed stiffness characteristics of electro-hydro-mechanical system

Qingqing TianLichen Gu 

School of Mechanical and Electronic Engineering, Xi’an University of Architecture and Technology, Xi’an, 710055, China

Corresponding Author Email: 
9 September 2017
27 February 2018
30 June 2018
| Citation



This paper aims to enhance the speed stiffness of the electro-hydro-mechanical system (EHMS). Focusing on the variable speed pump-controlled hydraulic motor system (VSPCMS), a typical EHMS, a mathematical model was established to discuss the coupling mechanism between multiple system parameters under the load condition, the physical meaning of system speed stiffness was explained, and the law of speed stiffness was disclosed under the action of multi-source variables. Moreover, several experiments were carried out to explore how the system speed stiffness is affected by three leading influencing factors in the VSPCMS, hydraulic motor displacement, leakage coefficient (system temperature and pressure) and motor shaft inertia. The experimental data agree well with the theoretical results: the system speed stiffness is positively correlated with hydraulic motor displacement and hydraulic motor shaft inertia and negatively with leakage coefficient. The research findings lay a theoretical basis for enhancing system speed stability, reducing speed fluctuations and optimizing system design.


electro-hydro-mechanical system (EHMS), Variable speed pump-controlled hydraulic motor system (VSPCMS), speed stiffness, multiparameter coupling

1. Introduction
2. Multiparameter Coupling Mechanism
3. Speed Stiffness Analysis
4. Experimental Verification
5. Conclusions

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