Search results

Filters

  • Journals
  • Date

Search results

Number of results: 5
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

The paper investigates a significant influence of transients on steady states in a matrix converter with the one-periodic control strategy. Proposed controller can be used as an interconnection device within a power system for a power flow control. However, the presence of inductances in external systems has the significant influence on steady state of a matrix converter operation. The special current injection method has been developed to ensure a proper operation of a matrix converter. Presented analysis of steady states is carried out in a frequency domain using the harmonic balance method. Obtained numerical results, which are confirmed by a time domain analysis, prove the effectiveness of the proposed method.
Go to article

Authors and Affiliations

Dariusz Borkowski
Tadeusz Sobczyk
Download PDF Download RIS Download Bibtex

Abstract

The paper presents a new method for simultaneous tracking of varying grid impedance and its uncertainty bounds. Impedance tracking consists of two stages. In the first stage, the actual noise estimate is obtained from least squares (LS) residua. In the second stage, the noise covariance matrix is approximated with the use of residual information. Then weighted least squares (WLS) method is applied in order to estimate impedance and background voltage. Finally uncertainty bounds for impedance estimation are computed. The robustness of the method has been verified using simulated signals. The proposed method has been compared to sliding LS. The results have shown, that the method performs much better than the LS for all considered cases, even in the presence of significant background voltage variations.

Go to article

Authors and Affiliations

Dariusz Borkowski
Szymon Barczentewicz
Download PDF Download RIS Download Bibtex

Abstract

The paper presents abilities and advantages following from the use of the harmonicbalance method for analysis of steady state of a multiphase system with switching devices on example of a matrix converter. Switching elements are modelled as resistances with step-wise variable parameters, what allows to describe the converter by a linear infinite set of equations. The analysis in frequency domain is presented on example of the one-periodic control strategy. External systems were also added using the Thevenin method approach. The numerical calculation results of a linear equations set were verified by the variable structure method in a time domain and the numerical convergence was confirmed. Furthermore, the exemplary complex system was analysed using the cascade method and current waveforms were obtained.

Go to article

Authors and Affiliations

Dariusz Borkowski
Tadeusz J. Sobczyk
Download PDF Download RIS Download Bibtex

Abstract

This paper presents an analytical model of a three-phase axial flux coreless generator excited by permanent magnets, with special focus on determining the model pa- rameters. An important aspect of this model is the derivation of a coefficient that corrects the flux on the inside and outside edges of the magnets. The obtained parameters are ver- ified by performing field analyses and measurements. A comparison of the results show satisfactory convergence, which confirms the accuracy of the proposed analytical model.
Go to article

Authors and Affiliations

Natalia Radwan-Pragłowska
Tomasz Węgiel
Dariusz Borkowski

This page uses 'cookies'. Learn more