Abstract:The alternating flow distribution pump can directly output alternating fluid flow through the continuous rotation of its built-in rotating valve plate, driving the hydraulic cylinder to generate excitation motion. Due to nonlinear factors such as internal leakage and friction within the alternating flow distribution pump and pump-controlled hydraulic cylinder, the bidirectional fluid flow generated by the pump may not be entirely symmetrical. As a result, the displacement center of the pump-controlled hydraulic cylinder may shift during the excitation process, thereby affecting its practicality. To address above problem caused by asymmetric fluid flow, a pump-valve-cylinder cascaded deviate regulation system was designed by placing a servo valve in series between the alternating flow distribution pump and the hydraulic cylinder. Additionally, a half-cycle piecewise deviate regulation control strategy based on the phase of the rotating valve plate was proposed. Based on the dynamic characteristics of the pump and valve, an AMESim-Simulink co-simulation model was established. System parameters were identified by experiment. The control performance was analyzed through simulation. A test platform was constructed to verify the effectiveness of the deviate regulation method. The research result showed that this method can effectively control the displacement center of excitation hydraulic cylinder controlled by the alternating flow distribution pump. Moreover, the servo valve remained mostly at a large opening, minimizing throttling losses. This approach ensured the high efficiency of the pump-controlled excitation system while improving its practicality.