The Key Technology Research On APF Governance Of Impact Load Harmonic

Along with our country to develop of the industry and agriculture, the integration of emerging power electronic technology, nonlinear devices is increasingly widely used in electric power system, has brought fragile power supply system harmonic pollution, triggering serious test of the power grid operation safe and reliable. In order to ensure power system safe and reliable, high efficiency operation, this series of questions must be researched, thus improving the quality of power supply and utilization of the power quality. Industrial field usually means of suppression of harmonic and compensating reactive power are all kinds of filter compensation devices, passive filter with its simple design and good economic characteristic application widely. But the running characteristics of type of passive power filter and compensation effect is easily affected by the impedance and the operation of the grid systems, only specific frequency compensation of harmonic current is even and system harmonic potential. Compared with active filter with its high controllability, ability of rapid response and flexible access system, plus he can produce every harmonic and reactive current in real time to load more and more dynamic, and the advantages of independent compensation application, or even replace passive filter.Electric arc furnace, rolling mill, such as electrolytic device severe changes near the impact caused by nonlinear load bus voltage and current at the same time randomness transients occur, especially in the larger impact current active filter under the condition of hard work. In this paper, on the basis of literature review, this paper from the principle of active filter and the basic structure of the harmonic current detection and control, then analyzes the0.4kV power supply system in a steel company active filter malfunction during the operation of the test data, on the basis of the impact load of the system operating characteristics and the specific operation of the active filter failure condition.Finally, the comprehensive mathematical modeling and data analysis results based on the research analysis of the active filter in such fundamental mechanism of the impact load operation malfunction, concluded that the impact load of active power filter is the load harmonic current amplification, harmonic current detecting inaccurate and dc side voltage control error, etc. Key issues to be solved, and tentatively puts forward the corresponding solutions to solve these problems, and through set up simulation model demonstrates the feasibility of the scheme.