A 17-level quadruple boost switched-capacitor inverter with reduced devices and limited charge current

Abstract

In this paper, a quadruple boost switched-capacitor multi-level inverter is proposed. The proposed structure utilizes a DC source, 11 switches, and a diode to achieve 17-level output voltage levels. This structure consists of three capacitors with the ability for self-balancing voltages. The capacitors achieve automatic voltage balancing through a series/parallel connection with the input voltage source. To control the switching pulses of the switches, level-shifted pulse width modulation (LS-PWM) strategy has been employed. A comparative evaluation has been performed between the proposed structure and structures presented in recent articles, considering various parameters such as voltage gain, number of DC sources, number of semiconductor devices, maximum blocking voltage (MBV), and total standing voltage (TSV). Considering this comparison, the lower number of semiconductor devices for generating a 17-level output with suitable voltage gain, and especially the cost-effectiveness of the structure, are the main advantages of the proposed configuration. In addition, a soft charging method has been employed to limit the inrush current of capacitors. Moreover, the power losses of the proposed structure have been investigated, indicating its acceptable efficiency. Finally, for the analysis and validation of the proposed structure's performance, an experimental prototype has been implemented and evaluated under various conditions. The results indicate satisfactory performance of the proposed structure under various stable and dynamic operating conditions.

A 17-level octuple boost switched-capacitor inverter with lower voltage stress on devices

“…( 22 ) 21 . In this equation, α is a weighting factor that can be considered 0.5 or 1.5 5 . The weighting factor is multiplied by TSV to calculate the cost factor under fair conditions.…”

“…The traditional constructions of multilevel inverters, known as a neutral point clamped (NPC), flying capacitor (FC), and cascaded H-bridge (CHB), are utilized to replace traditional two-level and three-level inverters in applications such as solar systems, electric vehicles, electric drives, etc. 5 – 7 . With the increase of output voltage levels in conventional structures, the device number has risen, and problems such as control complexity arise.…”

Switched Capacitor Inverter with Reduced Inrush Current and High Boosting Gain

“…The topology in [52] has more components than the proposed one and has a gain of only 2 times. A very recent article [53] presents a topology with a lesser number of components than the proposed one but offers only a 4 times boosting ability. Another factor known as the cost factor (CF) is also taken into consideration for comparison, and its estimation is carried out by Equation (12).…”