cascaded multilevel inverter (CMI) is one of the most popular multilevel inverter topologies. This topology is synthesized with some series connected identical H-bridge cells. CMI requires several isolated dc sources which brings about some difficulties when dealing with this type of inverter. This paper addresses the problem by proposing a switched capacitor (SC) based CMI. The proposed topology, which is referred to as switched capacitor single source CMI (SCSS-CMI), makes use of some capacitors instead of the dc sources. Hence it requires only one dc source to charge the employed capacitors. Usually, the capacitor charging process in a SC cell is companied by some current spikes which extremely harm the charging switch and the capacitor. The capacitors in SCSS-CMI are charged through a simple auxiliary circuit which eradicates the mentioned current spikes and provides zero current switching condition for the charging switch. A computer-aid simulated model along with a laboratory-built prototype are adopted to assess the performances of SCSS-CMI, under different conditions.

In this paper an optimal probabilistic scheduling model of energy hubs operations is presented. The scheduling of energy hub determines the energy carriers to be purchased as input and converted or stored, in order to meet the energy requests, while minimizing the total hub's cost. However, as many other engineering endeavors, future operating criteria of energy hubs could not be forecasted with certainty. Load and price uncertainties are the most unclear parameters which hub operators deal with. In this regard, the paper proposes a 2m + 1 point estimation probabilistic scheduling scheme for energy hubs with multiple energy inputs and outputs.

In this study, a fault‐tolerant structure and its controlling method for a cascaded H‐bridge multilevel inverter is introduced. When a fault occurs in one of the modules, the proposed circuit is able to isolate and eliminate the defective module from the whole system. The isolation and elimination is done by four relays in each module and a controlling circuit. This solution makes the system continue the normal operation by means of the remained healthy modules with decreased output voltage level. Therefore, the whole system failure will be prevented and higher reliability of the inverter will be guaranteed. Principles of operation and the controlling method are presented in this study. Reliability evaluation and comparison of the proposed fault‐tolerant structure and the conventional one are considered. To ensure the correct performance of the proposed cascaded H‐bridge multilevel inverter, a prototype has been synthesised in the laboratory. The obtained results affirm higher reliability and mean time to failure of the proposed circuit, so suitability of the proposed structure for sensitive industrial applications is confirmed.

This study presents a mathematical model to determine the optimal site and the size of plug‐in hybrid electric vehicles charging stations (CSs) in the distribution networks. The presented optimal planning is done along with considering the rate of customers’ participation in demand response programs (DRPs) at the presence of some uncertainties associated with the load values and electricity market price. In order to model the load, time‐of‐use DRP is used. The proposed model involves distribution system manager (DSM) benefit maximising derived from the appropriate use of CS for charging and discharging vehicle batteries, reliability improvement and supplying network's load demand at peak times as the objective function, technical limitation as constraint and the siting and sizing of electric vehicles CS as optimisation variables. The genetic algorithm method with embedded Monte Carlo simulation is used in order to solve the optimisation problem and is applied to the 9‐bus and 33‐bus networks. The test results indicate that not only does the appropriate planning have an economic benefit for DSM, but also voltage profile and power supply reliability for customers can be improved and active power losses can also be reduced.

Cascaded H-bridge multilevel inverter (CMI) is one of the most popular converters especially in renewabale energy applications. Beyond offering some significant benefits, this inverter suffers from the drawback of employing great number of components which reduces reliability of the inverter. Thus, designing a scheme to enhance reliability in this kind of inverter is of crucial importance. In this paper, a fault tolerant structure for cascaded H-bridge multilevel inverter is designed. Failure rates of the switches and diodes are calculated. Then, by using Markov method, reliability and mean time to failure (MTTF) of the mentioned inverter, before and after employing the suggested scheme, are evaluated. In order to prove proper performance of the suggested scheme, a laboratory built prototype is employed. The results show that employing the suggested scheme significantly enhances reliability and MTTF of the inverter.