Research On Instantaneous Power Control Of Asynchronous Motor

With the progress of the times,AC motor frequency control as the core of the AC speed control system has become the first choice for many speed control occasions.The development of AC speed control field can not be separated from the support of many key technologies.One of the core technologies is AC motor control technology.At present,a variety of advanced control algorithms are applied to the study of AC motor control technology,to make up for the lack of classical control theory,to a large extent improve the AC speed performance.However,in the actual situation similar to the secondary pressurized water supply system,the AC motor control technology needs to simplify the system structure and enhance the control performance under the condition that the speed control performance is better and the control precision is higher,reduce capital investment,reduce the cost of debugging time and many other aspects of comprehensive consideration.In this context,this paper analyzes these elements,based on the instantaneous power theory,and the traditional control of AC motor control ideas,proposed a three-phase cage asynchronous motor,simple structure and high real-time motor instantaneous power control scheme.Firstly,this paper takes the coordinate transformation as the starting point,studies the control structure of the traditional AC speed control mode,analyzes its structure and their potential problems.The instantaneous power theory is studied and the instantaneous power definition in three-phase circuit is analyzed.And the instantaneous power control of AC motor based on instantaneous power theory is analyzed.Secondly,based on the theory of instantaneous reactive power,in the stationary two-phase orthogonal coordinate system,the stator side instantaneous voltage and instantaneous current of three-phase cage asynchronous motor are decoupled,and in the same coordinate system,the asynchronous motor is running,the instantaneous reactive power is analyzed,and the combination of the two is put forward.The instantaneous power control scheme of the asynchronous motor is put forward.Finally,in order to verify the effectiveness of the instantaneous power control scheme,this paper uses MATLAB simulation platform to build the overall simulation model of the instantaneous power control system.The simulation results show that the instantaneous power control scheme is effective and feasible.The models of the traditional vector control system and the direct torque control system are built,and the main advantages and disadvantages of the instantaneous power control system are compared laterally.The simulation results and the comparison results show that the instantaneous power control system can realize the effective control of the three-phase cage asynchronous motor,and has the advantages of simple structure,few number of sensors and high precision,which can meet the requirements of realtime demand,while limited to the application of the combined cost of practical occasions.