The difference between polar and non-polar capacitors!
1. The principle is the same.
(1) Both store charge and release charge;
(2) The electric voltage on the electrode plate (here the electromotive force accumulated by charge is called dao voltage) cannot be changed suddenly.
(3) The difference lies in different media, different performances, different capacities, different structures and different usage environments and uses. Conversely speaking, according to the needs of production practice, people experimentally manufactured capacitors of various functions to meet the normal operation of various electrical appliances and the operation of new equipment. With the development of science and technology and the discovery of new materials, more high-quality and diverse capacitors will continue to emerge.
2. The medium is different. It is the substance between the two plates of the capacitor. Most polar capacitors use electrolyte as the dielectric material. Generally, capacitors of the same volume have large polar capacitance. In addition, different electrolytic materials and processes produce polar capacitors with the same volume capacity. Furthermore, the pressure resistance is also closely related to the use of dielectric materials. There are also many non-polar capacitor dielectric materials, most of which use metal oxide film and polyester. Because the reversible or irreversible performance of the medium determines the use environment of polar and non-polar capacitors.
3. Different performance. Performance is the requirement for use, and maximum demand is the requirement for use. If the metal oxide film capacitor is used for filtering in the power supply part of the TV, the capacitor capacity and withstand voltage required by the filter must be achieved. I am afraid that only a power supply can be installed in the case. Therefore, only polar capacitors can be used for filtering, and polar capacitors are irreversible. That is to say, the positive electrode must be connected to the high potential end, and the negative electrode must be connected to the low potential end. Generally, the electrolytic capacitor is above 1 microfarad for coupling, decoupling, power supply filtering, etc. Non-polarized capacitors are mostly below 1 microfarad, participating in resonance, coupling, frequency selection, current limiting, etc. Of course, there are also large-capacity and high-pressure-resistant ones, which are mostly used for the purpose of reactive power compensation of electric power, phase shifting of motor, and frequency conversion power supply.
4. Different capacities. As mentioned earlier, the capacitors of the same volume have different capacities.
5. The structure is different. In principle, without considering the tip discharge, any shape of capacitors can be used in the environment. The electrolytic capacitors (polar capacitors) that are usually used are round, and the square ones are rarely used. The shape of non-polar capacitors varies. Like tube type, deformed rectangle, sheet type, square type, round type, combined square type and round type, etc., see where it is used. Of course, there are intangibles, which refers to distributed capacitance. The distributed capacitance must not be ignored in high-frequency and intermediate-frequency devices.