Nowadays, use of multilevel inverters in high-power applications clearly can be seen. High quality and lower distortion the output voltage low blocking semiconductor switches are being presented as major privileges inverter compared to traditional source inverter. In this paper, a new topology is proposed fundamental block. The generalized using series connection blocks. has been analyzed both symmetric asymmetric operation modes. A great perfection levels number with minimum switching...

In this study, a novel structure for cascade multilevel inverter is presented. The proposed can generate all possible DC voltage levels with the value of positive and negative. results in reduction switches number, relevant gate driver circuits also installation area cost. suggested be used as symmetric asymmetric structures. Comparing peak inverse losses conventional inverters show superiority converter. operation good performance have been verified by simulation single-phase nine-level...

This paper proposes a new n-port hybrid dc circuit breaker for offshore multiterminal HVDC grid application. The can substitute n - 1 breakers at bus with adjacent transmission lines. system-level behavior of the proposed multiport is similar to other breakers. operation principles are introduced, analyzed, and compared existing solution in this work. components ratings solution, functionality device verified by simulation.

Recently applications of multilevel converters have been pointed out because some advantages include high‐quality output waveform, reduced harmonic distortion and lower electromagnetic interference. However, drawbacks such as increased number components like switches dc power supplies complex pulse width modulation control method are associated with these converters. In this study, a new cascade converter is introduced named ‘cascade‐multi‐cell’ converter. First, the basic constitutive...

This paper proposes a new device by combining features of an interline dual H-bridge current flow controller with the core idea hybrid HVdc circuit breaker for meshed grid application. The proposed can substitute two dc breakers at bus least adjacent transmission lines. In addition to interruption action, in one lines be controlled embedded controller. system-level behavior controlling is similar that typical and operation principles are introduced analyzed this work. component ratings...

In recent years, the multilevel inverters have become a practical solution for high‐voltage application and power quality issues. all topologies with several DC links, voltage balancing of capacitors is known as key problem. this study, novel topology chopper circuit capacitor in diode‐clamped (DCMLIs) proposed. Presented has less number switches respect to other proposed literatures. Suggested modular high reliability. Based on presented control system switches, only one switch turned at...

Emerging new voltage source converter based HVDC applications demand fast short-circuit fault current interruption. Fast dc circuit breakers are identified as the feasible solution to handle current. Switching overvoltage across is destructive for interrupter device and also other components of system. A topology solid-state breaker proposed in this paper. Instead conventional approaches, a pre-charged capacitor used soft switching. Different modes operation analysed design process...

Protection issue is identified as the main drawback of emerging multi-terminal HVDC grids. Multi-terminal grids demand fast short-circuit fault current interruption. The DC circuit breakers a promising solution can be implemented either bidirectional or unidirectional devices. In additional to less implementation cost, have power losses compared ones. A protection strategy for based on breaking devices discussed and assessed in this paper. performance examined under different scenarios...

Eliminating the specific harmonics especially low-order of output voltage 9-level inverter using SHE-PWM control scheme is investigated. Harmonic minimization intricate optimization problems because nonlinear transcendental equations have multiple local optima. Increasing degrees freedom in suggested method means that number switching angles increases. The able to eliminate high undesired harmonics. As increases, either traditional iterative techniques or resultant theory gets useless. In...

Protection issue is identified as the main drawback of emerging multi-terminal HVDC grids. Multi-terminal grid demands fast short circuit fault current interruption. Fast DC breakers a promising solution can be implemented either bidirectional or unidirectional devices. In addition to less implementation cost, have power losses compared A protection strategy for based on breaking devices discussed and assessed in this paper. The performance examined under different scenarios fourterminal...

This paper proposes a multilevel hybrid cascade-stack (HCS) converter. Recently, different new topologies for cascade-type converters have been suggested with the goal of reducing switch number, loss, PIV, etc. Meanwhile, output voltage steps increase, and number switches is predominately reduced in inverter comparison to conventional cascade converters. Additionally, reduction on-state introduced topology causes power loss drop decrease. Firstly, fundamental parts configuration are...

This paper investigates the application of unidirectional DC circuit breakers namely current releasing breaker in protection multi-terminal HVDC grids. The design procedure is extended for grid. Furthermore, a newly proposed fast non-unit algorithm adopted multiterminal results this study confirm that can protect grids similar to bidirectional breakers.

In this paper, a new topology is introduced for Doubly-Fed Induction Generators (DFIGs), applied in wind energy conversion systems. the proposed T-type converters are used back-to-back form instead of conventional converters. high-efficient three-level with high power quality. Furthermore, hysteresis-based predictive control method suggested rotor current DFIG. Therefore, discrete models DFIG and extracted. A equation also defined reference calculation which determines error. The can be...