Development of new capacitors for switching power converters

In order to reduce the size and weight of the switching power supply, it is necessary to try to improve the performance of the capacitor, increase its energy density, and research and develop new capacitors suitable for switching power supply applications, requiring large capacitance, small equivalent series resistance (ESR), small size, etc. It is reported that KEMET Electronics in South Carolina, USA, has developed a new 330μF solid tantalum capacitor in the late 1990s, and its ESR has been reduced from the original 500mΩ to 30mΩ.

The development and application of ultracapacitors (U1tra-CJapacitor) have also attracted people's attention. Ultracapacitors use double-layer electrodes produced on the surface of carbon electrodes to achieve an energy density of 0.2-10 W·h/kg, a power density of 100-5000W/kg, a charging time of 0.1-100min, and a cycle life of more than 10000h. For example, the capacity of 16 ultracapacitors connected in series and parallel can reach 20F, the voltage is 200V, the internal resistance is 0.16Ω, and the volume is only 500mm×480mm×300mm.