无码人妻久久一区二区三区app,久久无码字幕中文久久无码,亚洲人色婷婷成人网站在线观看,亚洲欧美乱综合图片区小说区

Hello! Welcome to the website of Dongguan Youchen Electronic Technology Co., Ltd.

Youchen Technology

Chip Capacitor/Electrolytic Capacitor/Ceramic Capacitor Supplier
18929295505
admin@dgyouchen.com
Current Page: Home > News > Common problem
News

Factors Influencing the Life of Electrolytic capacitor (I)

2019-07-25

Electrolytic capacitor are widely used in different fields of power electronics, mainly for smoothing, energy storage or filtering after AC voltage rectification, and also for non precision timing delay. In the MTBF prediction of switching power supply, the model analysis results show that Electrolytic capacitor is the main factor affecting the life of switching power supply, so it is very important to understand and influence the factors of capacitor life.

1. The life of Electrolytic capacitor depends on its internal temperature.

Therefore, the design and application conditions of Electrolytic capacitor will affect the life of Electrolytic capacitor. From the design point of view, the design method, materials and processing technology of Electrolytic capacitor determine the life and stability of the capacitor. For the application, the service voltage, ripple current, switching frequency, installation form, heat dissipation mode, etc. all affect the life of Electrolytic capacitor.

2. Abnormal failure of Electrolytic capacitor

Some factors may cause the Electrolytic capacitor to fail, such as extremely low temperature, capacitor temperature rise (welding temperature, ambient temperature, AC ripple), excessive voltage, instantaneous voltage, Very high frequency or reverse bias voltage; Among them, the temperature rise is the biggest factor affecting the working life (Lop) of Electrolytic capacitor.

The conductivity of capacitance is determined by the ionization capacity and viscosity of electrolyte. When the temperature decreases, the viscosity of the electrolyte increases, resulting in a decrease in ion mobility and conductivity. When the electrolyte freezes, the ion mobility is very low, resulting in a very high resistance. On the contrary, excessive heat will accelerate the evaporation of the electrolyte, and when the amount of electrolyte decreases to a certain limit, the lifespan of the capacitor will also end. When working in cold areas (generally below -25 ℃), heating is required to ensure the normal working temperature of Electrolytic capacitor. For example, outdoor UPS is equipped with heating plates in Northeast China.

Capacitors are prone to breakdown under overvoltage conditions, while surge voltage and instantaneous high voltage are common in practical applications. Especially in China, which has a vast territory and complex power grids in various regions, the AC power grid is very complex, often exceeding 30% of the normal voltage, especially for single-phase input. Phase deviation will exacerbate the normal range of AC input. The test shows that the commonly used 450V/470uF105 ℃ imported ordinary 2000 hour Electrolytic capacitor will leak and emit gas after 2 hours under 1.34 times of the rated voltage, and the top will burst. According to statistics and analysis, the failure of the Electrolytic capacitor output from the communication switching power supply PFC close to the grid is mainly due to the grid surge and high-voltage damage. The voltage of aluminum Electrolytic capacitor is generally selected for secondary derating, and it is more reasonable to reduce it to 80% of the rated value.

3. Analysis of Life Impact Factors

In addition to abnormal failure, the life of Electrolytic capacitor has an exponential relationship with temperature. Because of the use of non solid electrolyte, the life of the Electrolytic capacitor also depends on the evaporation rate of the electrolyte, resulting in a reduction in electrical performance. These parameters include capacitance, leakage current and Equivalent series resistance (ESR).

Refer to the formula for the expected life of RIFA company:

PLOSS=(IRMS) ² XESR (1)

Th=Ta PLOSSxRth (2)

Loop=Ax2Hours (3)

B=reference temperature value (typical value is 85 ℃)

A=capacitor life at reference temperature (varies depending on the diameter of the capacitor)

C=Number of degrees of temperature rise required to reduce capacitor life by half

From the above formula, we can clearly see that there are several direct factors affecting the life of Electrolytic capacitor: ripple current (IRMS) and Equivalent series resistance (ESR), ambient temperature (Ta), and total thermal resistance (Rth) transferred from the hot spot to the surrounding environment. The point where the internal temperature of the capacitor is the highest is called the hot spot temperature (Th). The hot spot temperature value is the main factor affecting the working life of capacitors. The following factors determine the external temperature (ambient temperature Ta) of the hot spot temperature value in practical applications, the total thermal resistance (Rth) transmitted from the hot spot to the surrounding environment, and the energy loss caused by AC current (PLOSS). The internal temperature rise of a capacitor is linearly related to energy loss.

During capacitor charging and discharging, the current flowing through the resistor causes energy loss, and the change in voltage also causes energy loss when passing through the dielectric. In addition, the energy loss caused by leakage current leads to an increase in the internal temperature of the capacitor.

Previous Page:Causes affecting the life of Electrolytic capacitor (II)

Next Page:Life of aluminum Electrolytic capacitor
Youchen Technology
Dongguan Youchen Electronic Technology Co., Ltd
Tel: 0769-85328400 8533526885336465
Fax: 0769-85308615
Email: admin@dgyouchen.com
Website: nndzy.com
Address: Floor 3, No. 7 Xinfeng Road, Shangsha Fourth Industrial Zone, Chang'an Town, Dongguan City, Guangdong Province
Yue ICP Bei No. 13008404
All rights reserved:Dongguan Youchen Electronic Technology Co., Ltd
In-line aluminum electrolytic capacitor manufacturer, SMT aluminum electrolytic capacitor manufacturer, direct sales, brand selection, model selection, price
Follow us:

Do you need our help? Welcome to leave your email!
18929295505  
2324774509
admin@dgyouchen.com
又黄又爽又色的视频| 日韩成人极品在线内射3p蜜臀| 女女女女bbbbbb毛片在线| 亚洲精品国产电影| 亚洲乱妇老熟女爽到高潮的片| 国产日产精品久久久久快鸭| 下面一进一出好爽视频| 精品人妻系列无码一区二区三区| 永久免费的av在线电影网无码| 久久精品国产精品国产精品污| 五月丁香综合激情六月久久| 永久免费的av在线电影网无码| 久久精品欧美日韩精品| 国产三级av在线播放| av人摸人人人澡人人超碰妓女 | 成人h动漫精品一区二区| 中文字幕无码不卡一区二区三区| 亚洲色丰满少妇高潮18p| 欧美亚洲色综久久精品国产| 久久综合亚洲色一区二区三区| 亚洲av色先锋资源电影网站| 午夜精品一区二区三区免费视频 | a级毛片在线观看| 特黄做受又硬又粗又大视频小说 | 国产精品久久久久无码av| 国产综合久久久久久鬼色| 法国白嫩大屁股xxxx| 推油少妇久久99久久99久久| 人人做人人爽人人爱| 国产精品无码久久久久成人影院 | 亚洲乱码日产精品bd在线观看| 国产精品无码专区av在线播放| 国内老熟妇对白hdxxxx| 欧洲av无码放荡人妇网站| 少妇被爽到高潮动态图| 乱色欧美激惰| 亚洲欧美成人一区二区三区| 中文字幕日本最新乱码视频| 午夜福利啪啪片| 国产av人人夜夜澡人人爽| 末成年女av片一区二区|