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EPE Journal Volume 06-1 - Papers
- Analysis and Implementation of a Space Vector Modulation Algorithm for Direct AC-AC Matrix Converters
- Snubber Energy Recovery Circuits with Soft-clamping for High Power Inverter Applications
- Analysis of Polyphase Phase-Shift Controlled a.c-d.c. Converters Based on Switching Vector Theory
- A Comparative Evaluation of Single-Phase SMR Converters with Active Power Factor Correction
- Review of the Testing Methods for Full-Load Temperature Rise - Testing of Induction Machines
EPE Journal Volume 06-1 - Editorial
By B. Sneyers
The Editorial of the EPE Journal Volume 06 N°1, "A sunny springtime", written by Ir. Brigitte Sneyers, the Editor of EPE Association
EPE Journal Volume 06-1 - Papers
By L. Zhang; C. Watthanasarn; W. Shepherd
The paper presents a control strategy for matrix converters based on the Space Vector Modulation technique (SVM). A novel and efficient modulation algorithm was developed and implemented using a digital signal processor (TMS320C30) incorporated with interface facilities. The control scheme is characterised by a real-time calculation of switchg on/off intervals and a capability to operate at high switching frequency. To verify the validity of the real-time modulator, an analogue simulation of a matrix converter was built. The output voltage waveforms generated by this converter are shown in association with their frequency spectra. The results agree well with the traget specification.
By X. He; B. W. Williams; S. J. Finney; Z. Qian
With increasing voltage ratings, insulated gate bipolar transistors (IGBT) are being used in power converter and inverter applications. such as motor drives and uninterruptible power supplies. The operating power-frequency bounds of any power semiconductor device can be extended and EMI decreased, by the use of snubbers. With device users wanting to extend the power-frequency bounds of IGBTs, the use of an inductive turn-on snubber is becoming viable. Since the use of a turn-on snubber with the IGBT would only be considered at high powers, significant snubber energy exist and recovery circuits are viable. In this paper, three turn-on snubber energy recovery circuits for IGBT power inverters are presented. Each configuration incorporates a soft-clamping circuit to limit switch over-shoot voltage at turn-off. The snubber energy is passively recovered into the DC supply through a high frequency transformer, and the transformer core flux is reset automatically. The operation process and circuit equations are given for each energy recvery circuit and can be used for practical inverter snubber optimal design. The presented circuits are suitable for use in high power IGBT inverters.
By J. Kyyrä
Analysis of midpoint and bridge converters is presented. It is based on switching vector, which is defined as a space-vector of switching functions of a polyphase system. It can be used merely as a time domain tool where, analogously to switching functions, it is stepwise in the complex plane. With the assumption of periodicity Fourier series representation is applied to the switching vectors and the harmonic components under steady state operation are computed. Space-vector combines all the converter phases into one equation, which means that the effect of a polyphase system is seen clearly and the necessary computation is short and efficient. In order to describe the quality of the converter and to compare midpoint and bridge converters with different phase numbers performance vector and performance index are discussed.
By A. Kandianis; S. N. Manias
In this paper an attempt is made to compare and evaluate three well-known and accepted SMR topologies with Active Power Factor Correction (APFC) , based on the criteria of switching stresses, efficiency, complexity of the control circuitand number of semiconductor devices used. To make this task easier, typical values of power semiconductor parameters for a medium power converter are used. As a result, the best suited topology for active input current waveshaping can be chosen for small to medium power applications. Finally, simulated key waveforms are obtained for all three topologies, which are used in the evaluation process.
By I. Colak; G. bal; C. Elmas
Determination of the temperature rise as well as the power dissipated inside induction machines as heat is a matter of interest to both customers as manufacturers. This is important since it affects the insulation materials, the cooling systems and the efficiency of the machine, such a direct loading test, back-to-back test, phantom loading test, forward short circuit test, variable inertia test and mixed-frequency test, have been reviewed. The experimental and simulation results of the mixed-frequency test using an inverter have been analysed in detail.