Modeling and control of an integrated electric parking brake system

The estimation of the frictional and clamping forces is one of the key issues in an integrated electric parking brake control system design and implementation. In this paper, we present a modeling and control system design for the integrated electric parking brake system (IEPBs). Based on the state-dependent switched IEPBs models, the whole working principles can be analyzed mathematically. Based on the mathematical models, clamping force, rotor angle position and motor current are set as the feedbacks respectively to compare the control performance. The simulation results show that with a force sensor, the clamping force can be controlled well, while the cost is increased seriously; and for the angle position feedback, the conventionally used position-force characteristic curve may change due to the external temperature and aging problem, which may result in an insufficient clamping force; the current control feedback strategy outperforms the other two strategies in terms of cost, implementation as well as the robustness with respect to the external disturbances. Finally, the proposed IEPBs model with current feedback control loop is verified through the experimental results with an on-off control method.