Research On Joint Inducatnce Parameter Optimize & Characteristic On Active Power Filter

With the development of Power Electric Technology and Automation Technology, there is incessant new evolvement in the research field of APF (Active Power Filter ). A 100KVA SAPF(Shunt APF) experimental prototype based on DSP (Digital Signal Processing) control system and IPM (Intelligent Power Module) has been empoldered independently in our lab. Although perfect effect has been obtained, when it is tested in the industrial filed, a few practical problems should be solved.According to the problems exist in the SAPF experimental set, in order to develop a kind of reliable and practical APF with high-performance and low-cost ,this thesis addresses itself to these issues: optimizing the parameters of the joint inductance, ameliorating the performance of the inductance, influence made by the materials of the inductance on the compensation effect and new design of the inductance. The amelioration method and design are verified by the simulation and experiment results.This thesis simply introduces the operation principle and experimental system configuration. Based on some documents, the joint inductance value calculate principle and gist are summed up. Appropriate inductance value is chosen by compensation performance. The air gap length is calculated by the idiographic parameters of the inductance and the experimental condition, and magnetic circuit simulation will use it in another chapter. In order to describe the influence that the material makes on the performance of the inductance, configuration and most parts of the inductance are introduced in details.Particularly the performance of the magnetic materials for the core of the inductance are compared, and their advantages and disadvantages are analyzed. Because the eddy current loss of the lamination increases as the applied frequency increases, and the magnetic performance will change as the frequency changes, the lamination is not suitable for the core in this experiment set.The frequency response characteristic under the PWM current is analyzed by the simulation and experiment results: when the low-frequency inductance is used in the high-frequency PWM application, the eddy current loss and hysteresis loss will increase as the applied frequency increases. At the same time, the AC loss caused by the skin effect and the proximity effect will force the AC resistance to increase as the applied frequency increases remarkably, the value of the inductance will reduce and the character of the inductance seems to be like the impedance's more and more.When the current(the frequency is 50Hz) acts on the inductance, the magnetic flux and the magnetic flux density distribution are analyzed by the magnetic circuit simulation. According to the request of the experiment, a new inductance who's core is made of Sendust is designed.The experimental results verify the validity of above theory and simulation analysis, and the bias-magnet elements of the hysteresis Loop-line was analysed.