Study On The Application Of Harmonic Detection In Power System Based On Embedded System

The Intelligent electrical network plan was published by the State Grid Corporation of China in may 2009.The plan is dedicated to making the modern power grids stronger, cleaner, cheaper and more efficient. The affection and harm to all kinds of power device, communication equipment and wiring from harmonic becomes more and more serious along with more application of non-liner loads. If we can know exactly the actual state of harmonic in power grids, we will take corresponding measures to avoid such damage and this is favorable for the secure operation of power grids. The purpose of this paper is to detect accurate harmonic content in the three-phase three-wire symmetrical circuits based on multilayered feed forward neural network and instantaneous reactive power theory.This paper presents a thorough study of how to train multilayered feed forward neural network and the i p ? iqmeasurement in instantaneous reactive power theory,made emulation analyses in MATLAB. This paper designed harmonic analysis device based on the emulation results. Embedded system was used in this device and the process chip S3C2440 was used as hardware core. The Power circuit, communication circuit, storage circuit, LCD circuit and Synchronization sampling circuit were also introduced in this paper. The software in harmonic measurement and analysis device which introduced in this paper was based on WINCE5.0 OS, the software including Boot loader, driver and applications.Instantaneous reactive power theory was used in harmonic analysis device which was designed in this paper. There several advantages of the theory such as smaller computational amount, higher precision and higher speed.The design supplies a fast and effective detecting method for harmonic father and analyzes equipments, such as active power filter. It can help to make the performance of those equipments much better.