Research On A New Structure Of Active Power Filter With Series Transformer

With the development of economic, power electronic devices are widely used in industry and our life. Harmonic pollution of power transmission and transforming system which is generated by UPS, commercial lighting, fluorescent lamp is becoming more and more serious. Hybrid active power filter as a method of harmonic suppression is widely developed and applied. Nowadays, it has important significance in environment of promoting"a conservation-minded and eco-friendly society".This paper adopts a new series hybrid active power filter with series transformer scheme. After inject the harmonic currents to secondary of ST, the harmonic impedance exhibited by the primary side of the ST will be large enough but small to fundamental current. So the harmonic currents flow into the branch of PPF, it is good for the system.The paper introduces researching background included harmonic generate and its damage, history and structure of APF and interrelated company. Harmonic detection methods are analyzed and confirmed. Research on SVPWM and obtain control strategy of whole circuit. Soft MATLAB is used to perform the simulation investigation of this control system.Some methods of phase-tracking are introduced among these a soft PLL was analyzed and emulated in detail.In the end software and hardware of the hybrid APF was designed. Hardware design included design of LC, sample circuit, peripheral circuit of IPM, protective circuit. Software design included software flow pattern, low pass filter, SVPWM and so on.