Application of gray-box identification in a new continuous rotary electro-hydraulic servo motor

In order to obtain performance parameters of a new type continuous rotary electro-hydraulic servo motor accurately, a grey-box identification model of the system was established. The gray-box modeling theory was used to identify parameters, and then unknown parameters were identified based on obtained parameters by using identification toolbox of Matlab. This identification model is based on physical structure of the system and input-output metrical data. It uses previous physics knowledge of the system, and considers the model uncertainty caused by procedure noise, thus it can hold the essential of the actual system. The results of experimental research testify that this method is effective for the achievement of accurate performance parameters of hydraulic system.