Development and Application of Hybrid Filter Protection Device

With the rapid growth of the proportion of new energy generation, harmonic problems in the power grid are becoming increasingly serious, posing a challenge to the safe and stable operation of the power system. This article studies the development and application of a hybrid active filter protection device (HAPF), which combines the advantages of active filters (APF) and passive filters (ACF) to effectively solve the harmonic problem in the power grid, especially suitable for new energy power systems. HAPF can filter out the target subharmonics generated by the converter station through precise control, while maintaining the reactive power compensation capability of the system. This article provides a detailed introduction to the working principle, software and hardware platform design, control strategy, protection configuration, and experimental verification of HAPF. The research results indicate that HAPF can effectively reduce the harmonic content on the AC side of the converter station, reduce the footprint of the filtering device, and avoid harmonic amplification problems caused by resonance between traditional passive filters and system impedance. In addition, HAPF also has a certain dynamic reactive power compensation capability, which can reduce the voltage fluctuations caused by the switching of compensation devices, and is of great significance for improving the power quality and system stability level of new energy power systems. The research results of this article provide new ideas and solutions for relay protection technology in new power systems, which have practical application value for promoting the high-quality development of new energy and the safe and stable supply of power systems.