Experimental Results of 47-Level Switch-Ladder Multilevel Inverter

Abstract

This paper provides experimental results for a 2.5-kW 47-level prototype of the switch-ladder multilevel inverter including the following: input and output voltage and current waveforms under resistive and inductive loads, efficiency, total harmonic distortion, voltage stresses across the switches, behavior of the system under fault condition, and no-load power dissipation. The most important advantage of this inverter is that only four switches conduct in each interval in low frequency. This matter, beside the elimination of switching losses, has made this inverter an efficient choice with 97% peak efficiency. The ability to continue working with open-circuit modules is another advantage of the inverter. Furthermore, some important factors behind the unreliability and inefficiency of inverters have been improved, including the following: low duty cycle of conducting switches, staircase voltage stresses across switches with low-voltage steppes, line switching frequency results in low temperature of switches, possibility of removing low-pass filters, and independence to capacitors. The inverter is proposed to be an advantageous choice in low-voltage stand-alone photovoltaic applications.

A Review of Control Techniques and Energy Storage for Inverter-Based Dynamic Voltage Restorer in Grid-Integrated Renewable Sources

“…Reduced components without H-bridge topologies [239][240][241][242][243][244][245][246][247], capable of generating bipolar waveform, consisting of several unit cells connecting in serial, are mainly used in medium voltage (MV) applications, as shown in Figure 34(b). Miscellaneous hybrid topologies are primarily designed for high power and MV/HV applications [248][249][250][251][252][253][254][255][256][257], as shown in Figure 35(a), whereas, some other topologies [258] use variable turn ratio transformers to generate more voltage levels while improving the LV supply from fuel cells, and standalone PV arrays are as shown in Figure 35(b). In MV grid-connected power systems, traditional topologies are still commonly employed.…”

Quick Search Algorithm-Based Direct Model Predictive Control of Grid-Connected 289-Level Multilevel Inverter

“…These studies are done to reduce switch count with increased voltage levels, improved transient response, lower number of capacitor balance circuits and level of modularity. The interested readers are referred to read [12,[32][33][34][35][36][37][38][39][40][41][42].…”

Modular multilevel inverter for renewable energy applications

“…The cascaded H bridge MLI are widely used in PV systems, UPS systems etc. In asymmetric type proper selection the value of the DC sources the quality of the output voltage waveform, the number of DC sources required and the requirement of power electronics components is managed in an effective manner [11][12][13][14][15][16][17]. For selecting the amplitude of the DC sources various method are adopted.…”