In order to study the flow characteristics of the brake variable axial piston pump,the mechanism model of the brake variable axial piston pump was established.Its variable principle was discussed,and the relevant formulas were derived.Considering the odd and even number of pump plungers,the flow characteristics of the brake variable axial piston pump were compared with those of the swash plate axial piston pump.The results show that the shape of the periodic transient flow curve of the pump changes,but the transient flow period does not change,whether the pump plunger number is odd or even;the flow pulsation of swash plate axial piston pump does not change with the swash plate angle,the flow pulsation of the brake variable axial piston pump increases with the increase of the rotation angle of the valve plate,and the increasing trend gradually increases.Therefore,when using the brake variable axial piston pump,it is necessary to consider that the maximum rotation angle range of the valve plate should be controlled as far as possible under the requirement of satisfying the actual displacement variation range of the pump,and it is very important for the brake variable axial piston pump to take necessary steady flow measures.