Filter capacitors are polarized and we call them electrolysis. One end of the electrolytic capacitor is a positive electrode, and the other end is a negative electrode. The positive terminal is connected to the positive terminal of the rectified output circuit, and the negative electrode is connected to the negative terminal of the circuit. In all circuits that need to convert AC power to DC power, setting a filter capacitor will make the electronic circuit work more stable and reduce the interference of the alternating ripple on the electronic circuit. The symbol of the filter capacitor in the circuit is generally represented by “C”. The larger the capacitance, the better the filtering performance. In order to obtain a better DC stability coefficient, the capacitance is generally selected to be hundreds of microfarads or thousands of microfarads. It has the characteristics of small size, light weight, easy to carry, very little leakage current, and insulation of the case. The new process of pouring is used to ensure the stable and reliable operation of the capacitor. This capacitor can be used for filtering in different levels of DC tests, and can also be used as a voltage doubler capacitor.
Filter capacitor is an energy storage device, which is often installed at both ends of the rectifier circuit to reduce the AC ripple ripple coefficient to improve the efficient and smooth DC output.
Specific can density, capacitors energy storage is strong
Low ESR, high ripple current handling capabilities and Large current shock
Low Inductance, Dv/dt large, frequency characteristics is good.
Self-healing property
Long lifetime(≥100000h)
High vacuum note oil, heat dissipation of capacitor performance is stable and reliable
Huge capacitance
High thermal conductivity
Low temperature rise The harmonic filter circuit consists of a capacitor series reactor, which forms the lowest impedance at a certain harmonic order to absorb a large amount of harmonic current. The quality of the capacitor will affect the stable absorption effect of the harmonic filter. Temperature has a great relationship. The higher the temperature, the lower the life. The filter full-film capacitor has the characteristics of low temperature rise, which can ensure its service life.
Low loss Dielectric loss angle tangent (tgδ): ≤0.0003.
safety In accordance with GB and IEC standards, internal unit capacitors are equipped with protection devices; when a line or unit capacitor is abnormal, the protection device will immediately act and automatically cut off the power to prevent secondary disasters. A discharge resistor is attached to ensure the safety of electricity consumption and maintenance. The shell is stamped from steel, and the inside and outside are coated with high-temperature baking paint with good weather resistance, which is extremely safe.
Convenience Small size and light weight, very convenient to carry and install.
Low-frequency filter capacitors are mainly used for electric filtering or filtering after transformer rectification, and their working frequency is 50Hz consistent with the mains; while high-frequency filter capacitors are mainly used for filtering after switching power supply rectification, and their operating frequency is several thousand Hz to tens of thousands. Hz. When we use low-frequency filter capacitors in high-frequency circuits, the low-frequency filter capacitors have a high internal resistance during high-frequency charge and discharge due to their poor high-frequency characteristics and high equivalent inductance. Therefore, in use, a large amount of heat is generated due to the frequent polarization of the electrolyte. The higher temperature will vaporize the electrolyte inside the capacitor and increase the pressure inside the capacitor, eventually causing the capacitor to bulge and burst.