Design and analysis of electrical properties of a multilayer ceramic capacitor module for DC-link of hybrid electric vehicles

Multilayer capacitors with high ripple current and high capacitance were manufactured. The electrical properties of these capacitors were characterized for potential application for DC-link capacitors in hybrid electric vehicle inverters. Internal electrode structures were designed to achieve high capacitance and reliability. A single multilayer capacitor showed 0.46 μF/cm³ of capacitance, 0.65% of dielectric loss, and 1450 V to 1650 V of dielectric breakdown voltage depending on the design of the internal electrode. The capacitor module designed with several multilayer capacitors gave a total capacitance of 450 μF, which is enough for hybrid electric vehicles. In particular, an equivalent series resistance of 4.5 mΩ or less will result in 60 Arms, thereby reaching the allowed ripple current for hybrid electric vehicles.