Farad capacitor , also known as super capacitors, gold capacitor
Farah capacitance capacitor capacity is much greater than usual . Because of its large capacity, the same external performance and battery , so there are called & ldquo capacitor battery & rdquo.
Farad capacitor are electric double layer capacitor , it is the world has been put into mass production of electric double layer capacitor capacity of the largest one, the basic principles and other types of electric double layer capacitors , are porous activated carbon electrodes and electrolyte composition the electric double layer structure obtained large capacity.
Feature
( 1 ) fast ging , ge for 10 seconds to 10 minutes up to 95 or more of its rated capacity
( 2 ) long cycle life and deep disge cycle times of up to 1 to 500,000 times , no memory effect &rdquo & ldquo
( 3 ) high-current disge capacity of super high energy conversion efficiency, low process loss , high-current power cycle efficiency &ge90
(4) high power density, up 300W/KG ~ 5000W/KG, corresponding to 5 to 10 times of the battery
( 5 ) products, raw materials composition, production, use, storage and dismantling processes are no pollution , is the ideal green power
( 6) The disge line is simple, without ging the battery ging circuit as high safety factor , long-term use of maintenance-free
( 7 ) ultra-low temperature acteristics, wide temperature range -40 ℃ ~ +70 ℃
( 8 ) to facilitate detection , the remaining capacity can be read directly
( 9) The capacity range is usually 0.1F1000F.
The main parameters
1 , the nominal capacity (CR): Products marked capacitor capacitance value.
Lower capacity electric mica and ceramic dielectric capacitors ( about 5000pF or less ) paper, plastic , and some form of ceramic dielectric capacitance center ( about 0005 & muF10 & muF) larger capacity normally electrolytic capacitor. This is a rough classification.
2 , category temperature range: capacitor design can be determined by continuous ambient temperature range that depends on its temperature limit corresponding category , such as the upper category temperature , the temperature of the lower class , rated temperature ( maximum continuous rated voltage is applied ambient temperature ) and the like.
3 , rated voltage (UR): at any temperature lower category temperature and the rated temperature between continuously applied to the capacitor rms or peak maximum pulse voltage or maximum DC voltage AC voltage .
When the capacitor used in high-pressure situations , we must pay attention to the impact corona . Corona is the presence of gaps between the dielectric / electrode layer produced , which can generate spurious signals in addition to damage to the equipment , it will also lead to breakdown of the capacitor dielectric . Under the conditions of AC or pulsating corona particularly prone . For all of the capacitors in use should ensure that the DC voltage and peak voltage of the AC and DC voltage ratings are not exceeded .
4 , loss tangent (tan & delta): Under the provisions of frequency sinusoidal voltage , the capacitor power loss divided by the capacitor reactive power.
In practical application , is not a pure capacitance capacitor , there is the equivalent internal resistance .
This relationship is expressed by the following equation : tan & delta = Rs / Xc = 2 & pif × c × Rs Therefore, the application of which should be ed in this parameter , to avoid self-heating is too large to reduce the failure of the device.
5, the temperature acteristics of the capacitor : the reference temperature 20 ℃ usually electrical capacity and the percentage of the capacity indicated temperature .
Advantages and disadvantages
Advantage
◆ achieve farad capacitance in a small volume
◆ no special control of the ging circuit and the disge circuit
◆ compared and battery overge , over disge will not have a negative impact on their life
◆ From an environmental point of view , it is a green energy
◆ ultracapacitors can be welded , so there is no battery contacts are not as firm and other issues
◆ welding operations on the production line , the other metal contact will not easily short-circuited, the metal to avoid a short circuit across the battery scrap phenomenon
Shortcoming
◆ If used improperly can cause electrolyte leakage phenomenon
◆ and electrolytic capacitors compared to its larger internal resistance , and thus can not be used in AC circuits