Communication base station

Status Analysis:

      In the communication room, switching power supply and UPS have become indispensable devices in the computer room, which can provide high quality voltage with high voltage stability, stable frequency and small waveform distortion to the load, and can provide power supply without interruption during static bypass switching. However, due to the switching power supply and UPS are nonlinear loads, they at the same time ensure the output high precision power of its own and will produce a large number of harmonic current at the input end, harmonic pollution to the power grid, also affect the room of other sensitive equipment, increase operation loss of the communication system of transformer, cable, busbar and other equipment, the diesel generator, transformer, power cable, power electronic equipment, low-voltage capacitor equipment damage, reduce the safety and reliability of distribution system. Therefore, the communication machine room must face the problem of harmonic control. The main load for UPS power supply, air conditioning, server; power quality exceed the standard project for the harmonic current; A phase current effective value of 222 ampere current harmonic distortion rate is 32.6%; B value of current 203 amperes, current harmonic distortion rate is 31%; C value of current 230 amperes, the total current harmonic distortion rate 35.6%.

Governance measures:

      According to the site conditions and the measured results, the main harmonic produced by DC power supply UPS and some nonlinear, solve the harmonic perfect set in accordance with the scheme, the compensation capacity of our company for shunt active power filter 100A, automatic tracking control of load harmonic current is generated, to ensure safe and reliable operation of the whole system.

The effect of Governance:

The total current distortion rate is reduced to 4.78%, the distortion rate of each subharmonic is within 1.5%, and the waveform of the non sinusoidal wave before the treatment is a sine wave. It can be seen that after the input of the filter, the harmonic of the system has been well suppressed, improving the reliability of the power supply system, eliminating the hidden trouble of the influence of the system harmonic on the communication system, and receiving good results.
1, the main load of intermediate frequency furnace, the six phase rectifier bridge is a typical harmonic source.
2. Due to the overload operation of the transformer, the voltage distortion is caused, and the harmonics are also greatly increased.
Change control 3, six phase rectifier makes the thyristor current in the process of phase change tube rate greatly, the load waveform presents a right angle change rate, wave coefficient is poor, harmonic distortion.
4. When the power factor can not meet the requirement, it is only due to the poor wave coefficient, so the conventional reactive power compensation equipment can not be compensated.
5. When the medium frequency furnace runs at full load, the total current distortion rate is 22.5%, and the main harmonic current is 5 times, 7 times, 11 times and 13 times.
6. The effective value of the single phase current is 761 amperes.