The Application Research Of Space Voltage Vector Control Method On Active Power Filter

The wide application of power electronic equipment makes harmonic problem become increasingly serious. Active power filter (APF) is considered as one of the most effective solution to control comprehensively the pollution of power system. It can suppress harmonics and compensate reactive power dynamically. Its compensative features can be barely influenced by the power network impedance characteristics. The fine filter characteristic of APF can satisfy the requirement of dynamical compensation. APF has been widely researched and developed in recent years. This thesis aims at the problem of harmonic which exists widely in elevator industry, and focus on the research of three phases shunt active power filter.Firstly, the situation of harmonic suppression technology and the development trend of APF are introduced briefly, and the structure of the active power filter and its working principle is studied. Secondly, the p-q and ip-iq detection methods based on instantaneous reactive power theory and used widely in three-phase system are studied in this paper. To overcome the disadvantageous effects resulted from distorted voltage, a novel harmonic and reactive currents detection method without phase locked loop (PLL) is presented. Thirdly, the control strategy of active power filter is described in detail. The space voltage vector control method not only has the high compensation precision and the fast response speed, but it can be accomplished with algorithm and achieved easily with digital method, so it is adopted for compensation current control in the paper.The three-phase shunt voltage active power filter system is simulated in MATLAB8.0/Simulink in order to validate the correctness and effectiveness of the harmonic detection method and control strategy of APF and is made further for theoretical analysis. The simulation results show that in some situations, i.e. for the distortionless and the distortion in a voltage and for the symmetrical nonlinear load and asymmetrical nonlinear load, the using method of harmonic detection and space voltage vector control technology for APF not only has very good harmonic control and compensation effect, but also has good dynamic compensation characteristic.In the thesis, the TMS320F2812 DSP is selected as the control core of the active power filter control system, and the software design of control scheme is introduced. The space voltage vector control algorithm program is compiled with the efficient assembler language. It is validated on the DSP development kit. The experimental results obtained from the laboratory system developed in this thesis verify the validity and effectiveness of the proposed software design of control scheme.