The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Intensive research is being directed to renewable energy due to their significant features. The converter is the core of the renewable energy system. Recently, a converter topology called Modular Multilevel Converter (MMC) has been introduced whose main challenge is the balance of its Submodules (SMs) capacitors voltages. Hence, a voltage sensor is required for each SM to measure its capacitor voltage;...
A new cascaded configuration of multi level inverter with reduced switching devices compared to conventional scheme is proposed. Proposed configuration has further advantages of less total harmonic distortion in output voltage and less current rating of the devices compared to the conventional scheme. Detailed analytical study has been made using proposed configuration for both 5-level and 11-level...
This paper presents a 2-2 discrete-time sturdy multi-stage noise-shaping (SMASH) delta-sigma modulator using source-follower-based open-loop integrators. The resolution of the SMASH delta-sigma modulator is enhanced by eliminating the first-stage quantization noise from the output. Using the proposed source-follower-based open-loop integrator, the operating speed of the modulator is efficiently improved...
The modular multilevel converters (MMC) has become an attractive research subject of power electronics due to its special topology. In this paper, a novel sub-module circuit for the MMC is proposed. Compared with the traditional sub-module circuits, the number of power semiconductors used in the proposed circuit is reduced by a quarter. Then, an improved three-phase multilevel topology is also constructed...
The paper presents a new four-level voltage source converter (VSC). Compared to conventional four-level converters, this proposed converter has fewer components and can be used for a higher power density system in low and medium voltage applications. Its principles and advantages are studied in this paper. The effect of various redundant switching states on the voltages of flying capacitors is analyzed...
This paper assesses the use of a modified three phase VSI topology with additional switches (H8) together with suitable modulation techniques as a mean for common-mode voltage reduction in electric drives with the aim of mitigating the onset of harmful bearing currents. Bearing currents in inverter-fed motors are related to the high dv/dt variation, induced at the motor terminals by the converters...
The paper proposes a three phase nine level T-type neutral point clamped (9L-T-NPC) inverter for medium voltage induction motor drive. The primary objective of the proposed inverter is to improve the output voltage quality with reduced number of devices and passive components. The generation of nine levels in the output pole voltage is achieved using only ten switches per phase. Although the similar...
This paper proposed an unequal zero voltage vector distribution modulation strategy to suppress the zero-sequence current of five-phase open-winding fault-tolerant fractional-slot concentrated-winding interior-permanent-magnet (FTFSCW-IPM) motor driving system with common DC bus. Compared with the conventional eliminating common-mode voltage vectors modulation strategy, this method can well suppress...
A capacitor voltage-balancing control strategy based on switching state redundancies is proposed for the hybrid stacked five-level converter. In order to obtain the balancing properties for flying capacitors, a hybrid model in state-space representation is established by considering the continuous and discrete variables. The proposed balancing strategy can control the flying capacitor voltages to...
Transformer-less single-phase grid-tied inverter is attractive due to low cost, high efficiency, and small size. However, leakage current and second-order ripple power have to be well dealt with. Because the leakage current is a potential threat for body safety and the ripple power will decrease overall efficiency and system reliability. Both issues become obstacles for practical applications. This...
This paper proposes two hybrid asymmetric cascaded multilevel inverters. Both inverters consist of the series connection of a three-level (3L) H-bridge cell and a nine-level (9L) H-bridge cell with an unequal dc voltage ratio of 1:8. The topologies of the 9L H-bridge cell are based on modular multilevel cascade converter (MMCC) with double-star chopper cells (DSCC). Both the proposed inverters can...
This paper introduces a single-phase matrix converter (SPMC) excited rotary transformer system to replace the slip rings of traditional wound field synchronous machine (WFSM). Compared to an inverter excited rotary transformer system, the matrix converter is compact due to the absence of a bulky DC Link capacitor. In this paper, the proposed SPMC uses a new constant volts per Hz modulation method...
Z-source inverters (ZSIs), compared to the conventional two-stage architecture, embrace some interesting features, like the reduced size and complexity of the entire conversion system. Many research activities have been established to improve the performance of the so-called ZSI since it has been proposed in 2003, and several modifications have been introduced since then. These modifications include...
An analytical approach for accurate calculation of the conduction and switching power losses associated with the switching devices in the 5-Level 3-Phase Back to Back E-Type Converter (5L3ϕ BTB E-Type Converter) has been proposed in this paper. The 5L3ϕ BTB E-Type Converter is composed by two different multilevel topologies: the 5-Level E-Type Inverter and the 5-Level E-Type Rectifier. The power losses...
This paper presents the design and control of a three-phase ground power supply unit for aircraft servicing. A new mixed technology converter composed by a three-phase Silicon Carbide (SiC) full bridge unit and a three-phase full bridge IGBT unit connected across the same dc link is used instead of the conventional full bridge configuration. In order to satisfy the stringent requirements of the output...
This paper investigates two five-level reduced hybrid inverters with split-wound coupled inductor and reduced number of components. The proposed inverters are composed of two legs, one of two levels and another of three-levels. Two types of three-level leg have been investigated: diode-clamped and flying capacitor. When compared with more conventional topologies consisting of two three-level legs,...
Multilevel topology and selective harmonic compensation (SHC) can control active power, reactive power, and to provide ancillary functions to support the grid. However, researchers find that with conventional L or LCL filter, multilevel SHC would act as noise source and inject harmonics to the grid by itself. Moreover, the output current of the multilevel converter is sensitive to the error of the...
Paralleled inverters have the merits of high power rating, improved reliability and convenient maintenance, but zero-sequence circulating current (ZSCC) will occur and lead to current distortion and system loss. The ZSCC control is more complicated when adopting three-level topology and increasing paralleled number. This paper addresses the suppression of ZSCC in multi-paralleled three-level T-type...
The three-level T type inverter has been extensively used in photovoltaic (PV) generation. Various PV panels in cascaded connection normally require unequal dc voltage to accomplish separate maximum power point tracking (MPPT). This paper proposes a DPWM-controlled three-level T type inverter for two strings of PV panels in cascaded connection. The proposed modulation is developed based on the so-called...
Current source converter (CSC) is mainly applied in high medium voltage drives. To increase the system power region and reduce the output harmonics, parallel connection is an easy-implement and practical method. There are mainly two types of parallel based topologies. The direct parallel connect of two back-to-back CSCs is the first type, the two DC links can be controlled from the rectifier side...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.