鋁電解電容器在在光伏逆變器中的應用最為廣泛，光伏發(fā)電系統(tǒng)產(chǎn)生的電流為直流電，但民用電力以交流供電為主，且太陽能發(fā)電最終將走向并網(wǎng)運行，這就意味著太陽能發(fā)電必須通過逆變器將直流電轉(zhuǎn)換為交流電來驅(qū)動家用電器等負載。因此，逆變器在太陽能發(fā)電系統(tǒng)中具有舉足輕重的作用。
Aluminum electrolytic capacitors are most widely used in photovoltaic inverters. The current generated by photovoltaic power generation system is DC, but civil power is mainly AC power supply, and solar power generation will eventually move to grid connected operation, which means that solar power generation must convert DC into AC through inverter to drive loads such as household appliances. Therefore, inverter plays an important role in solar power generation system.
光伏逆變器對鋁電解電容器的要求主要體現(xiàn)在高電壓、高耐紋波能力和長壽命。
The requirements of photovoltaic inverter for aluminum electrolytic capacitor are mainly reflected in high voltage, high ripple resistance and long life.
1.高電壓
High voltage
一般大功率的光伏逆變器，將轉(zhuǎn)化后的交流電直接并入高壓電網(wǎng)中，但從安規(guī)角度考慮，光伏電池組的輸出電壓一般不高于900V，可以選擇兩只450V電解電容器串聯(lián)，但為了提高安全性，可以選擇2只500V電解電容器串聯(lián)。所以需要高電壓等級的電容器來減少電容器的串接而提高可靠性。
Generally, high-power photovoltaic inverter directly integrates the converted AC into the high-voltage power grid. However, from the perspective of safety regulations, the output voltage of photovoltaic battery pack is generally not higher than 900v. Two 450V electrolytic capacitors can be selected in series. However, in order to improve safety, two 500V electrolytic capacitors can be selected in series. Therefore, high voltage capacitors are needed to reduce the series connection of capacitors and improve reliability.
2.高耐紋波能力
High ripple resistance
一般光伏逆變器流過電容器的電流為逆變器輸出電流有效值的0.44倍。如光伏逆變器的輸出電壓為線電壓250V，每輸出1kW功率對應的輸出電流約2.54A，流過直流母線電容器的電流為1.12A。100kW光伏逆變器的直流母線電容器需要流過112A有效值電流，所選擇的電容器的額定電流不應低于這個數(shù)值。如果一只電解電容器的額定電流不能滿足要求，要選擇多只電解電容器并聯(lián)方式獲得所需要的電流值。所以要求單只高耐紋波能力的電解電容器來減少電解電容器的并聯(lián)數(shù)量，提高整體可靠性。
In general, the current flowing through the capacitor of photovoltaic inverter is 0.44 times of the effective value of inverter output current. If the output voltage of the photovoltaic inverter is 250V, the output current corresponding to each output 1kW power is about 2.54a, and the current flowing through the DC bus capacitor is 1.12a. The DC bus capacitor of 100kW photovoltaic inverter needs to flow 112a RMS current, and the rated current of the selected capacitor shall not be lower than this value. If the rated current of one electrolytic capacitor cannot meet the requirements, select multiple electrolytic capacitors in parallel to obtain the required current value. Therefore, a single electrolytic capacitor with high ripple resistance is required to reduce the number of parallel electrolytic capacitors and improve the overall reliability.
3.長壽命
Long life
在太陽能發(fā)電系統(tǒng)中光伏電池板的使用壽命長達25年，而逆變器成為光伏系統(tǒng)一般只能使用5到10年，所以太陽能發(fā)電系統(tǒng)對光伏逆變系統(tǒng)的壽命要求為25年的水平。對于無源元件電解電容器，它的負極為電解液，會隨著使用時間的增長慢慢干涸而失效。這勢必需要電解電容器行業(yè)制造出更長壽命的電解電容器來符合光伏逆變器的要求。
In the solar power generation system, the service life of photovoltaic panels is up to 25 years, while the inverter can only be used for 5 to 10 years. Therefore, the service life of photovoltaic inverter system in solar power generation system is required to be 25 years. For passive component electrolytic capacitor, its negative electrode is electrolyte, which will slowly dry up and fail with the increase of service time. This is bound to require the electrolytic capacitor industry to manufacture electrolytic capacitors with longer life to meet the requirements of photovoltaic inverter.
三和螺栓式鋁電解電容器在光伏逆變器行業(yè)使用最為廣泛，經(jīng)過可靠性試驗完全符合新能源領(lǐng)域要求的長壽命，高紋波，高電壓的要求。如果您正好需要采購光伏逆變器的電容，歡迎和我們聯(lián)系，我們會第一時間為您提供現(xiàn)貨及技術(shù)支持。
Sanhe bolted aluminum electrolytic capacitor is the most widely used in the photovoltaic inverter industry. After reliability test, it fully meets the requirements of long life, high ripple and high voltage in the field of new energy. If you just need to purchase the capacitor of photovoltaic inverter, please contact us, and we will provide you with spot and technical support at the first time.