Never stop switch power technology |
| Author： Date：2016/12/21 10:32:52 |
Switching power supply because of its small volume, light weight and high efficiency advantages, which is widely used. But the traditional generally USES the mains switch power supply is not controlled rectifier and large capacitor filter are relatively smooth direct current (dc), rectifier diode nonlinear and filter capacitor energy storage effect, make the input current for a short time and high peak of the cyclical peak current. On the distortion of the input current Fourier analysis shows that it in addition to containing the fundamental wave, also contains rich higher harmonic component, especially the cage especially harmonics, which can cause low power factor of the ac switch power supply, not only brings a lot of harm to public power grid, and giant power unit based investment has increased a lot. Sum up have the following four o 'clock.
The public power grid, harmonic pollution, interfere with other electrical equipment. Second, the harmonic will increase the attenuation of the input current on a transmission line. Third, increase the power capacity of the front-end equipment, such as UPS, generator set, etc., thus increasing the infrastructure investment. Four, when three phase four wire system power supply is used, in phase with three harmonic in the midline, synthetic after line current is very big, may be more than the phase line current, and general lines diameter less than the phase center line configuration, can cause the midline serious overload, and according to the provisions of the safety line protection device, this will cause the midline overheating, serious can cause fire accident. In order to make the traditional ac power factor of switching power supply, meet the relevant departments to make technical regulations about electricity didn't prepare waveform distortion, for people to carry out the related technology research, the core objective is to current distortion correction of string, and phase with the voltage, so that the power factor is close to 1. Hence, the power factor is technology radiance. |