Research On Multi-Tuned Filter With Multiple Compensation Windings

Tuned AC filter is a practical apparatus used to suppress harmonic in power system and improve power factor. With the extensive application of power electronic techniques, some new structures, such as auto-tuning filter and continuously multi-tuned filter have brought great improvement of filter performance.The operating principles of continuously multi-tuned filter were discrided firstly, and its structure characteristics and existing problems were also analyzed in this paper. Against the low capacity of the continuously multi-tuned filter, a reactior with multiple compensation windings was proposed. It employed a new structure that there are several compensation windings on the second side and each compensation winding is companied by a harmonic current amplifier on the second side. Therefore, the proposed structure could satisfy the demands of large-capacity systems because each compensation winding has a low demand to the current amplifier.The compensation current amplifier with linear power circuit used in the continuously multi-tuned filter has large power loss and low efficiency, so a switching type power amplifier based on power electronic techniques is used to amplify the compensation current. It can not only solve the above problems, but also enhance the controllability of the whole filter system and improve the system reliability.On the basis of deeply researching the multiple compensation windings of controllable reactor and switching type power amplifier, a kind of improved power filter—the multi-tuned filter with multiple compensation windings was proposed. The simulations of whole system were realized by Matlab, and the control system of the filter is developed with DSP, which provided the precondition for the realization of the multi-tuned filter with multiple compensation windings.The simulation model of the multi-tuned filter with multiple compensation windings was established, and the experimental system was developed. The simulation and experiment results verify the feasibility of multi-tuned filter with multi-compensation windings.