A design scheme of hydraulic wind turbine with multi-accumulator is presented to smooth the output power. The mathematical models of the impeller, hydraulic pump, hydraulic motor, conventional accumulator, controllable accumulator control, and constant speed control in the system are established respectively. The AMESim simulation models of the system are also established. Under the stable wind speed condition, the characteristics of impeller torque, hydraulic drive and conventional accumulator are studied. Under the turbulent wind speed condition, the characteristics of controllable accumulator are analyzed, and the system characteristics with and without controllable accumulator are compared. The results show that when the wind speed is stable, only the conventional accumulator works, which can stabilize the power output effectively. When the wind speed changes sharply, the controllable accumulator opens intermittently. It stores energy as the wind speed increases rapidly and releases energy for the system as the wind speed drops suddenly. The application of the multi-accumulator effectively reduces the torque fluctuation of generator, increases the system stability, and improves the quality of power generation. (c) 2021 Elsevier Ltd. All rights reserved.