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.
In this paper a unified Impedance-based Stability Criterion (UIBSC) has been proposed for paralleled grid-tied inverters. Compared to the traditional Impedance-based Stability Criterion (IBSC) which needs to evaluate all minor loop gains (MLGs) of each individual inverter, the UIBSC only checks the derived global minor loop gain (GMLG) once to determine system stability. As a result, the computation...
In this paper, a comprehensive behavioral efficiency model of an electric motor drive system is proposed. The proposed model includes all possible motor drive losses without ignoring, approximating or assuming any of the inverter or machine losses, which are usually done for other efficiency models, hence the model is comprehensive. The input (DC electrical) and the output (mechanical) power of the...
A small-signal model based on droop control and utilized in microgrid of photovoltaic (PV) inverters is designed in this paper. The parallel-inverter system composed of two 1kVA PV inverters with no communication line is built on the basis of small-signal model. The influence of droop coefficients on the system stability and dynamic response ability is analyzed by utilizing root locus analysis in...
In this paper, a detailed mathematical presentation of Photovoltaic (PV) generation system, as well as its simulation model based on MATLAB / Simulink is established first. Its inverter-based simplified models, i.e. the switching-function equivalent model and average model, are simulated and compared quantitatively from different aspects. Simulation results reveal that the switching-function equivalent...
This paper discusses both dc-voltage balancing and ac-voltage minimizing of all the floating capacitors in a modular multilevel cascade inverter (MMCI-DSCC) intended for medium-voltage high-power synchronous-motor drives. It presents theoretical and numerical design considerations on both amplitude and phase of three-phase motor currents. A three-phase DSCC inverter with phase-shifted-carrier pulsewidth...
In electrified vehicles, distinct harmonic currents and corresponding ripple voltages exist mainly on the DC-links of the traction inverter and single-phase high voltage (HV) battery charger. Those harmonic currents are normally filtered by a bulk capacitor or an additional active filter (AF) circuit. This presents an obstacle for improving the power density as well as reducing the cost. This paper...
Integration of functions and features into silicon circuits is very important for a new power circuit design in order to reduce the electronic bill of material's (eBOM) cost and component count. These eBOM reductions increase the reliability and decrease the cost and size of a product. A low cost power micro-inverter using two application specific integrated circuits, analog power manager (APM) and...
The transformerless inverters are widely employed in grid-tied PV systems, since they feature higher efficiency and lower cost compared with the transformer based inverters. One of the critical problems for transformerless inverters is the common-mode leakage current issue, which leads to serious safety and EMI problems. This paper proposed an enhanced HERIC based single-phase transformerless inverter...
This paper proposes a soft-switched three-port single-stage inverter (TPSI) for a photovoltaic (PV)-battery system. Compared to the existing soft-switched TPSIs, the proposed TPSI has the advantages of using the least number of switches and that all of the switches are capable of being turned on under the zero voltage switching (ZVS) condition. A prototype of the TPSI without using electrolytic capacitors...
Common-mode current generated by the PWM AC drive at low modulation index and higher switching frequency results in overheating of the pre-charge resistor of the SCR based rectifier. In this paper, two modifications are proposed for the operation of SCR based rectifiers to significantly reduce the resistor overheating issue. The solution is cost and size effective when compared with alternative solutions...
This paper presents an active solution for the elimination of the leakage current, in a three-phase PWM inverter drive. With respect to a traditional three-phase bridge, the proposed solution reduces the common-mode voltage variations, both in amplitude and frequency. A novel architecture for the inverter is presented. Between the DC source and the traditional three-phase bridge, two active DC-decoupling...
In order to develop and validate smart grid technologies with complex control and communication, detailed modeling of distribution systems using the Real Time Digital Simulator (RTDS) is invaluable [1]. At the distribution system level, testing a 13 kV power electronic device without first validating its controls is cost prohibitive. RTDS provides a cost effective way to study smart grids at not only...
In this paper, a hierarchical control system based on a novel autonomous current sharing controller for grid-connected microgrids (MGs) is presented. A three-level hierarchical control system is implemented to guarantee the power sharing performance among voltage controlled parallel inverters, while providing the required active and reactive power to the utility grid. A communication link is used...
Distributed generation (DG) has gained popularity in recent years due to the increasing requirement for renewable power sources. A problem that exists with DG systems is the islanding of DG units that creates safety issues for personnel as well as the potential for damage to utility infrastructure. Therefore, islanding detection methods are utilized to mitigate the risk of islanded operation of DG...
In electric vehicle (EV) systems, bi-directional DC/DC converters are applied to interface the battery bank with the high voltage DC-link of the inverter. The control of the DC-link voltage is important for the high performance of the system. A DC-link voltage control strategy for the bidirectional DC/DC converter is proposed, which eliminates the need for detecting the operating mode and do not need...
Static power converters have widespread applications, such as ground power units (GPU) for airplanes. A modified static ground power unit based on 5-level Active Natural Point Clamped (5L-ANPC) multilevel converter is proposed in this paper. A new LS-PSC-PWM switching method for the 5L-ANPC converter is defined in this paper. The provided THD value of proposed converter will be less than those the...
This paper proposes a control system design for cooperated stabilizing control of PMSG based grid connected wind farm. In this study, a wind farm composed of PMSGs and SCIGs is considered to be connected to multi-machine power system. Though outputs of the SCIG based wind turbines are collected on AC network, PMSG based wind turbines are integrated in DC network with single grid side converter. In...
This paper provides a bridged-T voltage control scheme for a H bridge SiC inverter switching at 150 kHz for generating various waveforms at wide range of frequencies (60 Hz to 10 kHz) which is developed as a core loss test unit. Bridged-T controller attains the advantages of both the open and closed loop controllers. It has the fast dynamic response feature of the open-loop controller and zero steady...
The conversion between DC and AC power will typically introduce a low-frequency pulsation power in the DC side of single phase power converter which may create instability, lowers its efficiency, and reduces the reliability. In this paper, a novel Power Decoupling Modular (PDM) with 2 series differential decoupling capacitors at the ac side is proposed. Compared with the DC PDM, the proposed modular...
This paper presents the development of a single-phase online Uninterruptable Power Supply (UPS) system using a HPF front-end Boost converter with integrated Power Factor Correction (PFC) and DC-DC functions and an ordinary Full-Bridge as the single-phase output inverter. Besides the front-end stage with integrated PFC and DC-DC functions, the main feature of the proposed solution is the use a Proton...
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.