Research On APF Control System Based On Fusion Of Multiple-harmonic Detection Method

In recent years, because of a substantial increase of nonlinear loads in industrial production, nonlinear power electronic devices get a large number of applications, which leads to the harmonic pollution in power grid becoming serious increasingly. Active power filter(APF) is developed in recent years, which is the main equipment for harmonic suppression. This thesis researches the active power filter control system based on multiple harmonic detection method fusion, which is under the strong support of MOHURD’s project equipment intensive intelligent building electricity and energy saving technology research”.For APF’s whole organization, the control system is very important, whether it is superior directly influences the harmonic governance effect of APF.For various reasons, for example processing performance, the control system was designed based on DSP TM3S20F2812 in this paper, the double DSP structure has a very large control and computing power, which can completely meet the APF’s requirements for hardware control system. When APF works, accurate and efficient harmonic current detection is the precondition of harmonic compensation. At present, a lot of kinds of harmonic current detection methods come into practice, but there is no any kind of method that can satisfy the system’s requirements on accuracy and speed at the same time. Harmonic detection becomes one of the bottlenecks to improve the working characteristic of APF.This thesis mainly researches the control system of APF and harmonic current detection method. Firstly, the principle and characteristics of APF is introduced, and the hardware and software of the control system is analyzed. Secondly, this thesis carries out the simulation research of the traditional FFT harmonic detection method, and following carries out the simulation research of the emerging harmonic detection method based on instantaneous reactive power theory. lastly,this thesis analyses and compares the advantages and disadvantages of this two methods, and puts forward harmonic current detection method which based on the two method mutual fusion,at the same time carries out the simulation by use of this method.