Abstract:

For the complex hydraulic nonlinearity and time-varying friction disturbance of the Integrated Electro-hydraulic Brake System （IEHB）， an adaptive pressure control strategy is proposed. The outer-loop pressure controller introduces in a dynamic linearization model of hydraulic characteristics and realizes the adaptation of nonlinear hydraulic characteristics based on real-time identification of model parameters by a sliding mode observer. The inner-loop servo controller adopts pressure-based continuous friction compensation and back-stepping dynamic surface control to address frictional disturbance in the transmission mechanism. Hardware-in-the-loop test results show that， compared with the existing advanced cascade pressure control， the designed pressure control strategy exhibits higher control accuracy and robustness in various operating conditions， significantly improving the pressure control performance of IEHB under different hydraulic circuit structures.

Key words: vehicle engineering, integrated electro-hydraulic brake system, dynamic linearization, adaptive pressure control, hardware-in-the-loop