Study On Harmonic Propagation Suppression In Two-end Power Supply Network

The two-end power supply network which is one connection way with high reliability of power distribution network is the necessary choice for sensitive loads.Because of the harmonic resonance between system inductors and capacitors,the harmonic propagation may be amplified seriously in the two-end power supply network,which aggravates the problem of harmonic pollution and threatens the safety of system equipment.Firstly,this paper analysizes the haomonic propagation characteristic on the basis of the uniform transmission line model of the two-end power supply network.Futhermore,the operation principle and the harmonic suppression effect of the traditional RAPF strategy are discussed,which points out that the traditional RAPF strategy for a radial distribution network or a closed-loop distribution network can not suppress the harmonic propagation amplification in the two-end power supply network.Secondly,in order to damp out harmonic propagation amplification in the two-end power supply network with single-ended harmonic source,this paper proposes a discrete frequency controlling RAPF harmonic suppression strategy and a site selection strategy of discrete frequency controlling RAPF.Both of the two strategies could suppress harmonic propagation amplification effectively,and the site selection strategy of discrete frequency controlling RAPF has a better harmonic attenuation effect and avoids the “whack-a-mole” problem.The theory analysis,simulation and experimental results validate the effectiveness of the two proposed strategies.Thirdly,aiming at the harmonic propagation amplification in the two-end power supply network with two-end harmonic sources,this paper proposes a double discrete frequency controlling RAPF harmonic suppression strategy and a series IAPF harmonic suppression strategy.Both of the two strategies are able to suppress the harmonic propagation amplification of the harmonic sources on the two ends simultaneously,and have well adaptability to the change of line parameters.The theory analysis,simulation and experimental results validate the effectiveness of the two proposed strategies.Finally,a single-phase experimental analog circuit of the two-end power supply network based on lump-parameter model and the single-phase experiment platforms of discrete frequency controlling RAPF and series IAPF controlled by the TMS320F2812 DSP are built to clarify the effectiveness of these proposed strategies in this paper.