根据相关数据统计，薄膜电容器的应用场景正在不断扩大，下游应用以输配电、电机驱动为主，分别占下游应用市场规模的 31%、23%，其余应用场景还包括电源/适配器/DC-DC 转换、照明镇流器、可再生能源 DC-Link 等，而对应的应用终端电力电网建设、照明、家电、新能源发电、新能源汽车等全球市场均以我国为主要应用市场。
According to the statistics of relevant data, the application scenarios of film capacitors are expanding. The downstream applications are mainly power transmission and distribution and motor drive, accounting for 31% and 23% of the market scale of downstream applications respectively. Other application scenarios also include power supply/adapter/DC-DC conversion, lighting ballast, renewable energy DC Link, etc., while the corresponding application terminals include power grid construction, lighting, household appliances, new energy power generation China is the main application market for new energy vehicles and other global markets.
What are the common application scenarios of film capacitors?
Large household appliances such as refrigerators, washing machines, and air conditioners need to drive large motors to work. Film capacitors play different roles in motors, control circuits, and frequency conversion circuits.
In the lighting field, film capacitors are mainly used in the ballasts of fluorescent lamps, high-pressure mercury lamps, high-pressure sodium lamps, metal halide lamps and other high-strength gas discharge lamps. From the perspective of the change trend of the relevant revenue of the lighting business of the film capacitor leading enterprises, the overall demand for film capacitors in the lighting field is slowly declining.
New energy vehicles
The application of film capacitors in the field of new energy vehicles is mainly divided into three parts: inverter of new energy vehicles, on-board charger (OBC) and supporting charging pile.
逆变器中主要使用薄膜电容和铝电解电容，其中薄膜电容用于高压电路部分，起着 EMI和 DC-Link 的功能；MLCC 则大多用于低压电路部分。
Thin film capacitors and aluminum electrolytic capacitors are mainly used in the inverter, among which thin film capacitors are used in high-voltage circuit, playing the role of EMI and DC Link; MLCC is mostly used in low-voltage circuit.
On board charger (OBC)
OBC中薄膜电容主要有 EMI 电容、DC-Link 电容&缓冲电容、谐振电容、功率因数校正等。此外，薄膜电容在 DC-DC 转换器也有应用。
Film capacitors in OBC mainly include EMI capacitor, DC Link capacitor&buffer capacitor, resonant capacitor, power factor correction, etc. In addition, thin film capacitors are also used in DC-DC converters.
在直流充电桩中，也需要大容量、高价值的 DC-Link 电容进行缓冲。随着直流快充充电桩输出功率的增长，单桩薄膜电容器用量具有提升空间。
In the DC charging pile, large capacity and high-value DC Link capacitors are also required for buffering. With the increase of output power of DC fast charging pile, the amount of single pile film capacitor has room for improvement.
Photovoltaic wind power
光伏太阳能板吸收光照能量产生直流电压，而输电系统使用交流电压，因此与新能源汽车类似的，需要使用逆变器实现 AC/DC 转换。光伏逆变器中，薄膜电容被用在三个用途：
Photovoltaic solar panels absorb light energy to generate DC voltage, while the transmission system uses AC voltage. Therefore, similar to new energy vehicles, inverters are required to achieve AC/DC conversion. In photovoltaic inverters, thin film capacitors are used for three purposes:
C1, C2: prevent harmful high-frequency current, reduce electromagnetic interference in DC power lines, and protect solar panels;
C3: IGBT and other switching devices are prone to damage during state switching, and are usually buffered with a polypropylene film capacitor;
C4: The filter capacitor matched with AC in the inverter output is usually metallized film polypropylene capacitor.
Thin film capacitors in wind power generation systems are mainly used in several parts of the converter electrical system, and their functions are very similar to those in photovoltaic power generation inverters:
C1 (buffer capacitor): switching devices such as IGBT are prone to damage during state switching, and are usually buffered with a polypropylene film capacitor;
C2（直流链路滤波电容器）：直流链路电容有助于保护逆变器免受瞬时电压尖峰、浪涌和 EMI 的影响；
C2 (DC link filter capacitor): DC link capacitor helps protect the inverter from transient voltage spikes, surges and EMI;
C3 (output filter capacitor): the filter capacitor matched with AC in the converter output, usually also a metallized film polypropylene capacitor.
The film capacitor industry is changing from the past demand driven by household appliances and lighting to the demand driven by new energy vehicles and photovoltaic wind power. The high growth of the industry superimposes on the expansion and share increase of leading companies. The film capacitor industry has a promising prospect.