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EPE Journal Volume 23-4 - Papers
- Analysis of Conduction Losses for Zero-Current-Switching Quasi-Resonant Buck Converter
- Capacitor Voltage Balancing in a Three-Level-Converter-Based Energy Storage System
- Modified Combined DTC and FOC based Control for Medium Voltage Induction Motor Drive in SVM Controlled DCMLI
- A Nearly Constant Switching Frequency Current Error Space Vector Based Hysteresis Controller for an IM Drive with 12-sided Polygonal Voltage Space Vectors
- On the Role of the Shaft End and the Influence of Frame Size and Load Coupling on the RF Emission Characteristics of Induction Motors
- Solid-State System for Copper Vapor Laser Excitation
EPE Journal Volume 23-4 - Editorial
By Juha Pyrhönen; Jarmo Partanen; Jero Ahola; Braham Ferreira
Editorial: Welcome to EPE'14 ECCE Europe, Lappeenranta, Finland, 26-28 August 2014, written by Juha Pyrhönen, Jarmo Partanen, Jero Ahola and Braham Ferreira
EPE Journal Volume 23-4 - Papers
By N. Goryashin; A. Solomatova
A conduction power loss evaluation method which is important in design of quasi-resonant buck converter operating at zero-current-switching (ZCS) is observed in this paper. A new approach to conduction loss evaluation for wide operation range and voltage ZCS-converters is proposed. It allowed understanding fundamental difference between switch networks conduction losses with PWM, half-wave and full-wave ZCS modes of operation. The main statements are confirmed by experimental results quoted in the paper.
By S. Burusteta; J. Pou; S. Ceballos; I. Marino; J.A. Alzola; V.G. Agelidis
This paper discusses a grid-connected energy storage system based on two three-level (3L) converters: a DC-DC one and a neutral-point-clamped inverter. When compared to a system using standard two-level converters, the main advantages of this system are: higher efficiency, smaller reactive components allowing for a system cost reduction and its capability to handle higher voltage and power. A modulation strategy for the DC-DC converter which includes the neutral-point voltage balance control is proposed. The capability of the DC-DC converter to cancel the inverter’s neutral-point voltage oscillations is also analyzed. Results are presented to illustrate the extended operation area without imbalances. Design guidelines to size the DC-link capacitors are given for a practical implementation. Experimental results taken from a 10 kW 3L DC-DC converter prototype are provided to show the capability of this particular converter to keep neutralpoint voltage balance.
By H. M. Suryawanshi; U. V. Patil; M. M. Renge; K. D. Kulat
Modified combined direct torque control (DTC) and field oriented control (FOC) based method is proposed in this paper to improve the performance of induction motor (IM) drive. The proposed method includes combined advantages of DTC and FOC schemes. An algorithm is developed for closed-loop control of the proposed control method and the scheme is implemented in space vector controlled five-level diode-clamped inverter. For this, an experimental prototype is developed to control three-phase, 3-hp IM drive. The comparative performance of proposed control method, DTC and FOC with experimental results in SVM controlled five-level inverter is presented to validate the effectiveness of the proposed control scheme. Also, the switching states are selected so as to control the inverter output voltage as well as reduce the common mode voltage (CMV) of the drive.
By Najath Abdul Azeez; Anubrata Dey; K. Mathew; Jaison Mathew; K. Gopakumar
In this paper, a current error space vector (CESV) based hysteresis controller for a 12-sided polygonal voltage space vector inverter fed induction motor (IM) drive is proposed, for the first time. An open-end winding configuration is used for the induction motor. The proposed controller uses parabolic boundary with generalized vector selection logic for all sectors. The drive scheme is first studied with a space vector based PWM (SVPWM) control and from this the current error space phasor boundary is obtained. This current error space phasor boundary is approximated with four parabolas and then the system is run with space phasor based hysteresis PWM controller by limiting the CESV within the parabolic boundary. The proposed controller has increased modulation range, absence of 5th and 7th order harmonics for the entire modulation range, nearly constant switching frequency, fast dynamic response with smooth transition to the over modulation region and a simple controller implementation.
By Ville Niskanen; Annette Muetze; Jero Ahola
A novel nonintrusive radio-frequency- based method to detect discharge bearing currents occurring in variable-speed drives has been presented previously. Further understanding of the emission characteristics of the discharge and of the electric machine in which it occurs will extend its areas of application. To this aim, this paper addresses the modeling of the machine as an antenna, identifying the shaft ends to play a key role in RF pulse transmissions. Experimental and theoretical studies are carried out for squirrel-cage induction machines of different shaft heights, with the lengths of shafts and loads connected through different forms of coupling.
By V.Yu. Khomich; M.V. Malashin; S.I. Moshkunov; I.E. Rebrov; E.A. Shershunova
The present paper describes an all-solid-state high voltage nanosecond pulse generator for pumping a copper vapor laser. The main feature of this device is using a high voltage switch composed of a stack of insulated gate bipolar transistors (IGBT), what makes it compacter and more cost effective than traditional systems based on thyratrons and vacuum tubes. A fast transformer circuit provides highly synchronous on/off control of the IGBT stack. Two-stage magnetic pulse compressor is used to enhance the system efficiency. The developed laser pumping system generates current pulses with amplitude of 230 A and rise time of 30 ns at pulse repetition rate of 15 kHz. Average laser output power of 13 W was obtained under these pumping conditions.