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The power supply is an important part of the communication system. Extensiveuse of computers, servers and other semiconductor components and high-powernonlinear loads, resulting in a large number of harmonics, cause "pollution" on thepower system, increase the presence of harmonics, input supply and electricityadditional loss of the equipment, the equipment from overheating, reduce theefficiency and utilization of the equipment; transformer copper loss; accelerate theaging of the capacitor, the capacitor loss increases, it will cause the resonance toproduce harmonic current amplification, making the capacitor due to overheating,over-voltage and not the normal operation of many hazards. This research is on theharmonic analysis and control for communication power, according to a practical caseof capacitor burns in a hub station of Tianjin Mobile company.First, this paper introduces the harmonic causes and the role of parallel reactivepower compensation device. Then, principles of capacitors for harmonicamplification are analyzed; and present researches on harmonic suppression methodsare introduced. Secondly, through the site power supply system in the hub of powersupply harmonics data measurement, in-depth analysis of the capacitor is damagedand burnt the reasons causing harmonic interference resonant over-current, causingcapacitor overheating, resulting in the power supply system short-circuit paralysis.Finally, the installation of active filters, series reactor, and update the highanti-interference capacitors, harmonic control measures.Harmonic control measures for the practical application of the power quality ofthe hub’s power supply system has been significantly improved, low-voltagedistribution harmonic current distortion rate of4.1%harmonic voltage distortion isreduced to1.9%. the impact of the harmonic pollution one equipment is basicallyeliminated. Meanwhile, the economy has improved significantly, transformers, themaximum allowable capacity from1000kVA up to1100kVA. The increase in theactive filter losses, the transformer low-voltage side of the active power reduces9.6kW, high-pressure side of the active power reduces the12kW, the energy savingeffect is obvious.In this paper, the harmonic analysis of practical cases, control methods and recommendations to solve the problem of communication power system harmonicshas the versatility and the reference value.
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