Analysis of voltage ripple and design for DC-link capacitor in three-phase voltage source inverters

作者：Pei Xuejun^*; Chen Cai; Kang Yong

来源：Transactions of China Electrotechnical Society, 2014, 29(3): 254-259+269.

• Dc link capacitor
• Dc-link
• High-frequency harmonics
• Sinusoidal pulse width modulation
• Three-phase inverter
• Three-phase voltage source inverters
• Total harmonic distortion (THD)
• Voltage ripples

This paper analyzes the harmonic components of the input current in the three-phase voltage source inverter under sinusoidal pulse-width modulation (SPWM), third-harmonic injection PWM, and typical space vector PWM (SVPWM). The analysis results show that the DC-link current only contains the high-frequency harmonics at the switching frequency, its multiples and the sidebands for balanced and linear loads. The equations of the voltage ripple at different time intervals are derived for the DC-link capacitor during one switching period. Based on the equations of the DC-link voltage ripple, a design principle is presented for the DC-link capacitor. Simulation and experimental results show that the inverter can achieve low total harmonic distortion (THD) based on the proposed design principle. Therefore, the correcfness of the analysis and design is verified.

• 出版日期2014
• 单位华中科技大学