電解電容是通過(guò)電解質(zhì)作用在電極上形成的氧化層作為絕緣層的電容,通常具有較大的容量。電解質(zhì)是液體、膠凍狀富含離子的物質(zhì)。大多數(shù)電解電容都是有極性的,也就是在工作時(shí),電容的正極的電壓需要始終比負(fù)極電壓高。
Electrolytic capacitors are capacitors that use an oxide layer formed by the action of an electrolyte on the electrode as an insulation layer and typically have a large capacity. Electrolytes are liquid, gel like substances rich in ions. Most electrolytic capacitors have polarity, which means that during operation, the positive voltage of the capacitor needs to always be higher than the negative voltage.
電解電容廣泛用于家用電器和各種電子產(chǎn)品中,容量范圍大,一般為1?33000μF,額定工作電壓范圍為6.3?700V。它的缺點(diǎn)是介電損耗,大容量誤差,最大允許偏差為+100%,-20%。電解電容的耐高溫性差,并且由于長(zhǎng)時(shí)間存放而容易發(fā)生故障。
Electrolytic capacitors are widely used in household appliances and various electronic products, with a large capacity range, generally ranging from 1 to 33000 μ F. The rated working voltage range is 6.3-700V. Its disadvantages are dielectric loss, large capacity error, and maximum allowable deviation of+100%, -20%. Electrolytic capacitors have poor high-temperature resistance and are prone to malfunctions due to long-term storage.
電解電容的金屬箔是正極(鋁或鉭),并且正極緊密附著于金屬氧化物膜(鋁氧化物或五氧化鉭),是電介質(zhì)。陰極由導(dǎo)電材料,電解質(zhì),可以是液體或固體和其他材料組成。由于電解質(zhì)是陰極的主要部分,因此以電解電容器命名。同時(shí),正極和負(fù)極電解電容器不能錯(cuò)誤地連接。
The metal foil of an electrolytic capacitor is the positive electrode (aluminum or tantalum), and the positive electrode is tightly attached to a metal oxide film (aluminum oxide or tantalum pentoxide), which is a dielectric. The cathode is composed of conductive materials, electrolytes, which can be liquids or solids, and other materials. As the electrolyte is the main part of the cathode, it is named after an electrolytic capacitor. At the same time, the positive and negative electrolytic capacitors cannot be connected incorrectly.
當(dāng)電容器施加的電壓超過(guò)其耐壓時(shí),或者當(dāng)極化電解電容器的電壓極性反轉(zhuǎn)時(shí),電容器的泄漏電流將急劇上升,從而導(dǎo)致電容器的內(nèi)部熱量增加,并且電解質(zhì)將產(chǎn)生大量的氣體。為了防止電容器爆炸,在電容器殼體的頂部上壓了三個(gè)凹槽,以便電容器的頂部可以在高壓下首先破裂并釋放內(nèi)部壓力。
When the voltage applied by the capacitor exceeds its withstand voltage, or when the polarity of the polarized electrolytic capacitor voltage is reversed, the leakage current of the capacitor will sharply increase, leading to an increase in internal heat of the capacitor and the electrolyte will produce a large amount of gas. In order to prevent the capacitor from exploding, three grooves were pressed on the top of the capacitor shell, so that the top of the capacitor can first rupture and release internal pressure under high voltage.
電解質(zhì)在加熱時(shí)會(huì)膨脹,并且在膨脹到一定程度時(shí)會(huì)打開(kāi)電容器的外殼并泄漏出去。這通常稱(chēng)為泄漏。當(dāng)溫度緩慢升高時(shí),電解電容器中的電解質(zhì)會(huì)緩慢泄漏;但是當(dāng)溫度上升非??鞎r(shí),電解電容器的內(nèi)部會(huì)迅速膨脹,這會(huì)立即拉伸電解電容器的外殼,甚至破壞整個(gè)外殼,這就是爆炸。
Electrolytes will expand during heating, and when they expand to a certain extent, they will open the shell of the capacitor and leak out. This is commonly referred to as a leak. When the temperature slowly increases, the electrolyte in the electrolytic capacitor will slowly leak; But when the temperature rises very quickly, the interior of the electrolytic capacitor will rapidly expand, which will immediately stretch the outer shell of the electrolytic capacitor and even damage the entire shell, which is an explosion.
極化電解電容器通常在電源電路或中頻和低頻電路中發(fā)揮作用,以進(jìn)行電源濾波,去耦,信號(hào)耦合,時(shí)間常數(shù)設(shè)置和直流阻塞。通常不能在交流電源電路中使用。當(dāng)用作直流電源電路中的濾波電容器時(shí),其陽(yáng)極(正)應(yīng)連接到電源電壓的正端子,陰極(負(fù))應(yīng)連接到電源電壓的負(fù)端子,不可反向。 ,否則會(huì)損壞電容器。
Polarized electrolytic capacitors typically play a role in power circuits or medium and low frequency circuits for power filtering, decoupling, signal coupling, time constant setting, and DC blocking. Usually cannot be used in AC power circuits. When used as a filter capacitor in a DC power circuit, its anode (positive) should be connected to the positive terminal of the power supply voltage, and the cathode (negative) should be connected to the negative terminal of the power supply voltage, and cannot be reversed, Otherwise, it will damage the capacitor.
電解電容器溫度升高的原因是其自身的功耗異常增加,并超過(guò)了其可以承受的功耗。功耗增加的原因可能是:電解電容器過(guò)電壓;紋波電流大;反極性。
The reason for the temperature increase of electrolytic capacitors is that their own power consumption has abnormally increased, exceeding the power consumption they can withstand. The reason for the increase in power consumption may be: overvoltage of electrolytic capacitors; High ripple current; Reverse polarity.
但是,在某些電容器的制造過(guò)程中,頂部的凹槽不合格,電容器內(nèi)部的壓力會(huì)導(dǎo)致電容器底部的密封橡膠彈出。此時(shí),電容器內(nèi)部的壓力突然釋放,并且會(huì)發(fā)生爆炸。一旦容量較大的電解電容器爆炸,其電源可能會(huì)危及人身安全。因此,不僅應(yīng)該從性能的角度來(lái)設(shè)計(jì)大容量的電解電容器,而且還應(yīng)該從安全性的角度來(lái)設(shè)計(jì)大容量的電解電容器。
However, in the manufacturing process of some capacitors, the top groove is not qualified, and the pressure inside the capacitor can cause the sealing rubber at the bottom of the capacitor to pop out. At this point, the pressure inside the capacitor suddenly releases and an explosion occurs. Once a large capacity electrolytic capacitor explodes, its power supply may endanger personal safety. Therefore, not only should large capacity electrolytic capacitors be designed from a performance perspective, but also from a safety perspective.