Analysis And Identification Of The Servo System

The thesis develops and identifies two systems. Airborne radar servo system and composite axis servo system System identification is one of the key of the control areas, because the exact dynamics model is the basis for the design and control of electromechanical systems, and it has a very important position. Use of relevant theoretical knowledge of system identification, identification of the controlled object’s structure and parameters, to establish a precise mathematical model of controlled object, which is a key step in the study of the control system, and then to study the control algorithm based on this model, so that it meet the requirements of the control system of indicators. This thesis has been working to identify the two servo systems, including airborne radar servo system’s identification on laboratory environment, as well as the crude turntable of the compound axis servo system’s identification on actual research projects work.Airborne radar servo system’s work consists four parts:identification of experimental design; determine the identified model’s structure; determining the identified model’s parameters; verify identification model. The first step of the task is to design the system’s hardware and software implementations based on the principles of servo system, gathering input and output data, to prepare for the model identification work. The input signal is M series collected by STM32, the output signal is the speed signal acquired by the encoder. Identification of the model structure is derived mainly AIC criterion system order. Identification of the model parameters were mainly taken by the two-step method, first of all using the correlation method to get the system’s nonparametric model-the impulse response, and then calculate the system’s parameter model using the least squares method-the transfer function. After determining the structural model and the parameters of the model, we have validated the effectiveness of the system model, the main method is to compare the model output and the actual output making the error less than a certain target, the experiment was to identify the model certificate true and reliable. Because airborne radar servo system needs to run in a special environment, such as high-temperature environment, vibration environment, so we want the system to be able to stable operation when certain changes occur in the controlled object parameter.Therefore, based on the identification model we have conducted a self-tuning PID parameter studies, primarily for the study of three loop control method based on fuzzy intelligent, the system has a certain degree of robustness. Finally, based on the above work, the system has a closed loop testing.The test results show that the system funcion is normal with communication running well.Composite axis servo system’s identification is based on a set of the input and output data having given by the project, we want to identify the crude turntable model of compound axis servo system. This set of data is oval track test data. After analysis showed that the main ingredient is a sinusoidal signal.Due to the sinusoidal signal can not fully incentive the system in the whole band, so we calculated input and output signals by first-order and second-order differential differential operation, it can inspire the system’s various modes. Due to the presence of the noise on the project, we apply the least squares fitting method for filtering the input and output signals. Based on these processed data, identify the various types of model systems. These models were selected from a relatively high precision model, and the validity of the model was validated. Composite fine turntable axis servo system is built on top of this coarse turntable, so the the identification of coarse turntable model provides an important basis for the analysis of the subsequent fine turntable.The main contents is to identified the two typical servo systems’s model., and then To verify the validity of the model, the results indicate that the model errors are in the required scope.Identification model is reliable.