A Self-Balancing Switched-Capacitor-Based Dual Boosting Nine-Level Inverter

Abstract

Switched-capacitor (SC)-based multilevel inverters (MLIs), are widespread in several application fields owing to their voltage boosting feature and inherent capacitor self-voltage balancing abilities. However, the issue of high impulse charging current restricts the usage of SC-MLIs in high-power applications. In this article, a nine-level (9L) SC-based inverter to solve this problem while conserving the beneficial features of conventional SC-MLIs is proposed. The devised structure has a twofold voltage gain with self-balancing ability which obviates the need for additional sensors. It consists of an integrated half-bridge module (IHBM), a nested cell, and an SC unit. A logic gate-based pulsewidth modulation (PWM) scheme is developed for the gating pulse generation that simplifies the overall control design. A comparison with other SC-MLIs to highlight the beneficial features of the proposed topology is included. From the results, it will be shown that the proposed inverter has improved reliability and reduced part count. Finally, the operation of the proposed topology is validated for both steady-state and dynamic operating conditions.