Analysis of Steady-State Characteristics for a Newly Designed High Voltage Gain Switched Inductor Z-Source Inverter

Abstract

This paper aims to develop a new switched inductor assisted strong boost Z-source inverter (SL-SBZSI) topology with high voltage gain and analyze the steady-state characteristics of the proposed topology. In the proposed topology, two switched inductors are used within the series impedance structure of the Z-source inverter (ZSI) in order to achieve the high voltage gain. The steady-state characteristics of the proposed topology are analyzed to disseminate its several advantages as compared to traditional ZSIs. The key advantages include the higher boost factor with lower shoot-through duty ratio and lower voltage stresses on capacitors as well as on switches of the inverter bridge. Furthermore, the proposed topology has the soft-start ability which significantly reduces the inrush start-up current while comparing with the traditional ZSI. In the proposed topology, a common ground is shared between the output AC voltage and the input DC voltage source which categorizes this topology to the doubly grounded inverter. The characteristics of the proposed SL-SBZSI are analyzed by considering two operating condition where the simple boost pulse width modulation (PWM) scheme is used to extract the shoot-through pulses. The characteristics of the proposed topology are also compared with different existing topologies along with the conventional modified capacitor assisted Z-source inverter (MCA-ZSI), whose boost factor is much closer to the proposed topology. Rigorous mathematical analyses are presented to clearly demonstrate the benefits of the proposed topology while simulation studies are carried out to demonstrate its distinct features as compared to the existing topology. Finally, experimental studies are conducted to further validate the theoretical and simulation results.

Z‐source inverter topologies with switched Z‐impedance networks: A review

“…Most of these topologies follow the extended SL cell structures to improve the gain of the inverter. In [84], the model of an SL strong boost ZSI (SLSB‐ZSI) (see Figure 19) was proposed where the SL cells have been composed on the multiple series impedance networks based on the idea in [85]. Although the SLSB‐ZSI has significantly improved the boost factor and achieved lower voltage stress on capacitors and semiconductor switches, the component count is high enough that shrunk the practical applicability of the inverter.…”

“…In the race of improving the voltage boost ability of the SL-ZSI, several other topologies have been studied in [80][81][82][83][84].…”

“…In the race of improving the voltage boost ability of the SL‐ZSI, several other topologies have been studied in [80–84]. Most of these topologies follow the extended SL cell structures to improve the gain of the inverter.…”

Leakage Current Reduction in Single-Phase Grid-Connected Inverters—A Review

“…There are many points of view from which inverters are classified, one of the essential classifications is made according to their power supply. In this way, three types of inverters are established-Voltage Source Inverter (VSI) [15], Current Source Inverter (CSI) [16] and Z-Source Inverter (ZSI) [17]. As a summary, the main classifications of these power converters are presented in Figure 2.…”

Optimal Robust LQI Controller Design for Z-Source Inverters

“…The substantial progress of modern power inverters is well underway for the penetration of renewable energy sources into power systems and many other industrial applications [1]. The Impedance Source Inverters (also called Z-Source Inverters or ZSIs) form a class of high-performance, highly reliable, and highly efficient yet low-cost inverters equipped with an X-shaped impedance circuit that enables shoot-through state [2,3].…”