Research And Practical Design Of Active Power Filter

As a kind of easy to use and clean energy, electric energy has been applied to all walks of life of industry and agriculture production. With the development of power and electronic technology, the application of electric energy is more widely. The modern various electric equipments extensively use transformation of electric energy, and during this process a lot of power harmonic were produced. Power harmonic will increase power loss of line, reduce utilization rate of power distribution equipment, cause the reactive power compensation capacitor damage due to resonance, increase the fault rate of electrical equipments.To solve the problem of power harmonic pollution, passive power filter was used early, but management is not complete; hybrid active power filter (HAPF) later developed could solve harmonic pollution a thoroughly, but the device is complex, reliability is low; with the development of power electronic device, current pure active power filter (APF) become the mainstream, it can not only compensate harmonic, but also solve unbalance of active power and reactive power, is the development direction of managing harmonic pollution.The main content of this paper is designing a set of AC400V/100A three phase four line active power filter which is practical high performance and parallel accessed. This filter has a high cost performance and highly intelligent, can adaptive work in the system of three phase three line and three phase four line. This paper has the following content:1. Power harmonic problems and solution; Discussion on key questions of APF’ current situation and practical products.2. The design of APF’s inverter, includes comparison and selection of topological structure, parameters selection of the inverter.3. The significance and implementation methods’selection of separation of APF’s harmonic, active power and reactive power.4. The design of APF control circuit, includes selection of DSP, signal processing of forward and back path, design of IPM drive circuit.5. The analysis of APF control strategy, highlights the principles of signal generator and phase locked loop, harmonic separation method and concrete realization of FFT, adaptive control and parameters self regulation functions, principles of output current regulator controlled by direct pulse width. 6. Program design, expounded the method to improve program operation efficiency, introduced program flow and time allotment of main program module.7. Sample machine test, detailed tested the main performance of APF sample machine.