The Simulation And Design Of Shunt Active Power Filter

Active Power Filter (APF) is a very effective device to control harmonic pollution in the power system. It is well known that because of the widespread use of power electronic devices and the non-linear loads, the harmonic currents and reactive current massive are injected into power grids, which make a large amount of energy waste and highlight threat to the safe operation and normal use of the power grids and of electrical equipments. As the strategic of building a conservation-oriented society was proposed in China's "11th Five-Year Plan", the research of using the APF application for harmonic and reactive management will have very broad application prospects.This paper describes the basic principles of the APF, the current classification of the APF and several circuit topologies, analyzing the structure of three-phase three-wire and three-phase four-wire of the APF system, establishing two models to figure out the limitations of three-phase three-wire APF power supply system in the actual application, introducing three current control methods and a space vector control method, introducing three harmonic detection theories in harmonic detection, making a detailed theoretical analysis on the design of the APF system which based on the instantaneous reactive power theory, establishing a three-phase four-wire system simulation model based on instantaneous reactive power theory of the APF system in MATLAB, verifying the feasible of the instantaneous reactive power theory in the software simulation.After a mount of theoretical analysis and verification, this paper designs a dual-CPU device of APF, including microcomputer as the main CPU and DSP as the second CPU. The work of hardware designing contains: microcomputer clock circuit and emulator interface circuits, DSP clock circuit and external memory expansion circuit, APF system voltage detection circuit, the absolute value of current conversion circuit and so on. The paper also designs the main and interrupts programs of microcomputer, the main program and started moving procedures of DSP. After debugging all the programs, the device was conducted actual tests and experimental analysis.