The new type of electro-hydraulic steering gear with direct drive volume control is a typical system with large inertia and small damping. To solve the problem of control rapidity, stability and quietness contradicting each other, the engineering application of active disturbance rejection control (ADRC) for the electro-hydraulic steering gear is studied.

First, the ADRC model of the electro-hydraulic steering gear is established and a transition process is designed to control the start-stop hydraulic impact. Next, a physical control test-bed is built, the stability of physical control is analyzed, the filtering effect of the algorithm is adjusted, an output filtering prediction module is added, and the big time delay of the electro-hydraulic steering gear is predicted and compensated. Finally, a comparative test of the algorithm control performance before and after optimization is carried out.

The experimental results show that, under the action of the improved ADRC control algorithm, the structural vibration of the electro-hydraulic steering gear in the start-stop transient state is reduced by about 6–10 dB, the position accuracy can be controlled within 1 mm, and the steering gear has good stability and followability under external interference such as load impact.

The results of this study can provide references for the stability control and ADRC algorithms of systems with large inertia and small damping.