AC parametric regulated power supply and its harmonic suppression
With the wide application of power electronics, on the one hand, bring great economic benefits, on the other hand, also bring the quality of power supply degradation, affecting many of the power quality is very sensitive to the power equipment, experts agree that microelectronic instrumentation and computer system failure, the vast majority of the quality of power supply due to problems caused by issues, such as: impact, low power factor, voltage dips, harmonic distortion, power failure, flicker and Interference with the signal voltage, etc., to solve these power quality problems many methods, input cost difference is very large, and the AC parameter voltage regulator power supply, also known as voltage regulator transformer (CVT), is one of the more effective ways to solve the power supply interference, and more and more attention, and has been widely used in communications base stations, aerospace, nuclear industry, railroads, hospitals, banks, finance and securities, public security, and other industrial, mining and industrial units, large and medium-sized, Small and medium-sized computers, computer networks, numerical control systems, program control systems, analytical measuring instruments, measurement and inspection, photocopiers, medical instruments and equipment, and other various equipment supporting the use of good results.
AC parameter voltage stabilized power supply basic principles and features
1, AC parameter stabilized power supply, also known as constant voltage transformer (Constant Voltage Transfomes) referred to as CVT.
2, constant voltage transformer and the main difference between ordinary transformers:
① function, although it is an iron core primary side, secondary side of the two windings separately, but it does not follow the input and output voltage and primary side, secondary side of the winding turns proportionality, and the output voltage does not change with the input voltage and remain constant.
② There are saturated and unsaturated regions in each section of the core of the magnetic divider of a constant voltage transformer.
③ Shunt capacitor and compensation winding with boost resonance.
3, the main features of the technical parameters
① Simple structure, no control components, only by two single components.
② simple structure, high reliability, the average trouble-free operating time is the highest among all kinds of AC voltage regulator.
③ high voltage stability, voltage stabilization range is wide, as seen from the source voltage effect, when the input voltage changes ± 20%, the output voltage changes ± 1.5%, when the input voltage changes ± 30%, the output voltage changes ± 3.5%, if the appropriate choice of the rated output load and the actual load ratio, you can extend the stabilized range of the * best state, so it is particularly suitable for the areas of large fluctuations in the grid voltage.
4, anti-interference performance: CVT is a voltage regulator, isolation, transformer trinity of transformers, input and output are completely isolated, the grid has a good two-way inhibition of impulse interference signals and attenuation, at the same time on the grid surge impact, instantaneous sudden changes, instantaneous flicker, static electricity, such as falling lightning and other interference have a good anti-interference ability.
5, fast response time, within 40ms.
6、Automatic overload protection
When the output power exceeds the rated value, the output voltage automatically drops to ensure the safety of electrical equipment, even if the output load short-circuit, will not be damaged, the load short-circuit is lifted will automatically restore the output voltage; with the load on the power supply or the power grid is disconnected and then resumed, the output will not produce over-voltage, such as twice the grid voltage (440V) short-term shock, the output will not produce over-voltage shock, thereby ensuring the safety of user equipment. operation.
7, waveform distortion. By the characteristics of its structure, the output waveform, the total harmonic distortion cut <5%, especially distortion is not affected by the input distortion, even if the input voltage square wave, the output voltage is also sinusoidal waveform or "purification" effect.
