選擇適合的電解電容要根據使用場景來選擇電解電容的電壓、容量、使用壽命等多個參數來綜合考慮，那么電解電容的不同參數分別代表什么含義呢？

　　The selection of suitable electrolytic capacitor should be based on the use scenario. The voltage, capacity, service life and other parameters of electrolytic capacitor should be comprehensively considered. What do the different parameters of electrolytic capacitor mean?

　　（1）額定電壓 VR：是設計電容時設計的而且表示在電容上的直流電壓。對于鋁 電解電容，額定電壓≤100 V 通常叫做低壓電容，而額定電壓>100 V 稱作（中）高 壓電容，常用的額定電壓有 6.3V，10V，16V，25V，50V，63V，100V，250V， 400V，450V，500V，630V 等。

　　Rated voltage VR: it is designed when designing the capacitor and represents the DC voltage on the capacitor. For aluminum electrolytic capacitors, the rated voltage ≤ 100 V is usually called low-voltage capacitor, while the rated voltage > 100 V is called (medium) high-voltage capacitor. The commonly used rated voltages are 6.3V, 10V, 16V, 25V, 50V, 63v, 100V, 250V, 400V, 450V, 500V, 630V, etc.

　　（2）工作電壓VOP：電容可以在額定電壓（包含一些疊加成份）下額定工作范 圍內連續工作。允許的連續工作電壓范圍為0V到額定電壓之間。在很短時間內， 因陰極鋁箔上有一層空氣氧化層，電容可以承受不超過1.5 V 的反向電壓。

　　Working voltage VOP: the capacitor can work continuously within the rated working range under the rated voltage (including some superimposed components). The allowable continuous working voltage range is between 0V and rated voltage. In a very short time, because there is an air oxide layer on the cathode aluminum foil, the capacitor can withstand a reverse voltage of no more than 1.5 v.

　　（3）浪涌電壓VS：是短時間內可以加在電容上的最大電壓，比如一小時內5次， 每次一分鐘。IEC 60384-4定義浪涌電壓如下：如果 VR ≤ 315 V，VS = 1.15VR， 如果VR > 315 V，VS = 1.10VR。

　　Surge voltage vs: the maximum voltage that can be applied to the capacitor in a short time, for example, five times in an hour, one minute each time. IEC 60384-4 defines the surge voltage as follows: if VR ≤ 315 V, vs = 1.15vr; if VR > 315 V, vs = 1.10vr.

　　（4）額定容量CR：是電容設計和標示的交流電容值。CR是由(IEC 60384-1 and IEC 60384-4)規定的特殊標準來測得的，對于電解電容一般測試條件為2倍工頻 （100HZ 或 120HZ），室溫。另外，容量誤差是電容實際容量離開額定容量分布范圍，一般會標在本體上，對于 AL 電解基本上標記為 M（±20%）。

　　Rated capacity Cr: it is the AC capacitance value designed and marked. Cr is measured by the special standards specified in (IEC 60384-1 and IEC 60384-4). For electrolytic capacitors, the general test conditions are 2 times of power frequency (100Hz or 120Hz) and room temperature. In addition, the capacity error is that the actual capacity of the capacitor leaves the distribution range of the rated capacity, which is generally marked on the body. For Al electrolysis, it is basically marked as m (± 20%).

　　（5）使用溫度范圍：即電容器能夠穩定工作的溫度范圍，目前常見的低溫極限值大致有-55℃，-40℃，-25℃幾種，高溫極限值大致有 85℃, 105℃ ,125℃，130℃ 等幾種。

　　Service temperature range: that is, the temperature range in which the capacitor can work stably. At present, the common low-temperature limit values are - 55 ℃, - 40 ℃ and - 25 ℃, and the high-temperature limit values are 85 ℃, 105 ℃, 125 ℃ and 130 ℃.

　　（6）使用壽命：使用壽命（也定義為服務壽命及操作壽命）定義為電容不超過指定失效率的可以達到的壽命。使用壽命是應用使用經驗以及加速老化試驗來得到的。如果負載低于額定值，使用壽命可以得到延長（比如低的工作電壓，電流及環境溫度），適當的散熱措施也可以延長使用壽命。

　　The service life and failure rate of the capacitor can be defined as the service life not exceeding the specified service life. The service life is obtained by applying service experience and accelerated aging test. If the load is lower than the rated value, the service life can be extended (such as low working voltage, current and ambient temperature), and appropriate heat dissipation measures can also prolong the service life.

　　（7）耗散因數 tanδ：是等效串聯電阻與等效串聯線路里(如下圖)容性電抗成分的比值，或者是在正弦電壓下有功功率（耗散功率）與無功功率的比值。

　　Dissipation factor Tan δ： Is the ratio of the equivalent series resistance to the capacitive reactance component in the equivalent series line (as shown in the figure below), or the ratio of active power (dissipated power) to reactive power under sinusoidal voltage.

　　（8）等效串聯電感 ESL：自身電感或者稱等效串聯電感來源于接線端子及電容 內部設計，如上圖。

　　Equivalent series inductance ESL: the self inductance or equivalent series inductance comes from the internal design of wiring terminals and capacitors, as shown in the figure above.

　　（9）等效串聯電阻 ESR：是指等效串聯線路的阻性成分。ESR 值與頻率，溫度 有關，而且與耗散因數有關，公式如右圖

　　Equivalent series resistance ESR: refers to the resistive component of the equivalent series line. ESR value is related to frequency, temperature and dissipation factor. The formula is shown in the right figure

　　（10）阻抗 Z：是指等效串聯線路的總的電抗值，它只要包括容量 CS的容性電抗 部分；電解液及接線端子的介電損失及歐姆阻抗 ESR 部分；由電容繞制及接線端子產生的感性電抗 ESL 部分。ESL 只取決于頻率，而容性電抗和阻性電抗則取決于頻率及溫度。

　　Impedance Z: refers to the total reactance value of the equivalent series line, as long as it includes the capacitive reactance part of the capacity CS; Dielectric loss and ohmic impedance ESR of electrolyte and wiring terminal; Inductive reactance ESL part generated by capacitor winding and wiring terminal. ESL only depends on frequency, while capacitive reactance and resistive reactance depend on frequency and temperature.

　　（11）漏電流 Ileak：由于鋁電解電容的特殊特性，其鋁氧化層也充當絕緣層，在 直流電壓施加很長時間后，還有一個小電流會繼續流過電容。這個電流叫做漏電流。漏電流小意味著電容的絕緣層設計的很好。

　　Leakage current ileak: due to the special characteristics of aluminum electrolytic capacitor, its aluminum oxide layer also acts as an insulating layer. After DC voltage is applied for a long time, a small current will continue to flow through the capacitor. This current is called leakage current. Low leakage current means that the insulation of the capacitor is well designed.

　　（12）紋波電流：用rms值來標示流過設備的交流電流，其原因是跳動及浪涌電 壓。最大允許紋波電流決定于環境溫度，電容表面積（散熱區域），耗散因數以及交流頻率等。由于熱應力對電容壽命有決定性作用，由紋波電流產生的熱量就是影響使用壽命的重要因數。

　　Ripple current: RMS value is used to indicate the AC current flowing through the equipment, which is caused by runout and surge voltage. The maximum allowable ripple current depends on the ambient temperature, capacitance surface area (heat dissipation area), dissipation factor and AC frequency. Because the thermal stress plays a decisive role in the service life of the capacitor, the heat generated by the ripple current is an important factor affecting the service life.