Digital Control Technique Of Hybrid Active Power Filter

With the rapid development of power electronics, it becomes a trend to take advantage of power electronics devices to control grid's power quality (including harmonic distortion). Among them, Power Filter is considered by most people to be one of the most effective methods to compensate harmonics and improve power quality. Because Hybrid Active Power Filter (HAPF) can combine both Passive Filter's large volume and Active Filter's flexible control capability together, HAPF becomes one focus of power electronics research.Research of HAPF generally focuses on topology of main circuit and control module design. This thesis discusses the digital control technique of HAPF.This thesis's main object is to design a digital controller of HAPF which can be commercialized and made into product. The controller's main part is DSP TMS320F2812.This thesis bases its discussion about digital control technique on the design of the digital controller of a high power HAPF. It mainly focuses on the basic requirements of real time control (including sample time and core calculating time), design of digital filter in dq algorithm and software reuse. Meanwhile, digital control inevitably brings in some problems, such as discrete method's choosing, zero-order hold problem, etc. This thesis gives suggestions on how to eliminate these problems according to analysis of bode graph.This thesis bases design and analysis on computer simulation. A small sample machine is made according to the actual HAPF and the result of experimentation can prove the correctness of the design.