Conference Proceeding

Novel modulation schemes minimizing the switching losses of sparse matrix converters

Power Electron. Syst. Laboratory, ETH Zurich, Switzerland
12/2003; DOI:10.1109/IECON.2003.1280564 ISBN: 0-7803-7906-3 In proceeding of: Industrial Electronics Society, 2003. IECON '03. The 29th Annual Conference of the IEEE, Volume: 3
Source: IEEE Xplore

ABSTRACT The switching losses of a three-phase sparse matrix converter (SMC) operating in the lower modulation range are minimized by employing the lowest and the second largest input line-to-line voltage for the formation of the converter DC link voltage. The resulting current stresses on the power semiconductors and the switching frequency ripple RMS values of the filter capacitor voltages and output currents are calculated by digital simulation and compared to conventional modulation. Finally, a modulation scheme is introduced which allows the generation of reactive input power also for missing active power transfer via the DC link and/or purely reactive load. This is a basic requirement for operating the SMC in boost mode where the output filter capacitor voltages have to be controlled sinusoidally also for no-load operation.

0 0
  • [show abstract] [hide abstract]
    ABSTRACT: While the known modulation and control techniques for four-leg matrix converters are based on pulse width modulation or three-dimensional space vector modulation, this paper presents a simple current control strategy based on prediction calculation to select the switching states of the converter. By using a predictive cost function, the optimal switching state to be applied to the next sampling time is selected. This is done in order to minimize the instantaneous reactive power on the input side and to obtain a positive dc-link voltage at any time, while maintaining a good tracking of the load currents to their respective references. The feasibility of the proposed strategy is verified by simulation results.
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: A novel approach based on indirect modulation, which significantly extends the reactive power control range for three-phase ac-ac matrix converters (MCs; applicable to all matrix topologies) and which is implementable with lowest computational effort, is proposed. This new method denoted as hybrid modulation facilitates the formation of reactive input current also for purely reactive load. The derivation of the modulation schemes, which rely on a decoupling of the output voltage and the reactive input current formation, is described in detail. Furthermore, the operating limits, i.e., the maximum reactive input current that could be formed for the given output voltage amplitude and load current amplitude, are determined. Finally, all theoretical considerations are verified by measurements taken on a 6.5-kW Very Sparse MC.
    IEEE Transactions on Industrial Electronics 01/2012; 59(1):194 - 210. · 5.17 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Common-mode voltage (CMV) is responsible for overvoltage stress to the winding insulation and bearing damage of an ac motor. High dv/dt of CMV raises leakage currents, which can cause serious problems such as motor damage and elec- tromagnetic noise to the equipment installed near the converter. This paper proposes two modulation strategies for indirect matrix converters that substantially eliminate CMV. The first method is developed by using the suitable couple of nonzero space vectors instead of zero space vectors in the inverter stage. The maximum voltage transfer ratio of this method is unaffected and remains 0.866. The second one, which is useful for low-voltage operation, is approached by choosing the medium and the lowest positive line- to-line input voltages in the rectifier stage to generate the dc-link voltage and by placing suitable zero space vectors in the inverter stage. In the second method, the maximum voltage transfer ratio is 0.5. Both methods can mitigate the peak value to 42%. In addition, while the first method provides the same performance to the con- ventional method, the second method can reduce significantly the harmonic components of line-to-line output voltage. Simulation and experimental results are shown to verify the effectiveness of the proposed methods. Index Terms—AC/AC converter, common-mode voltage (CMV), direct matrix converter (DMC), indirect matrix converter (IMC), matrix converters (MCs), space vector pulsewidth modulation (SVPWM).
    IEEE Transactions on Industrial Electronics 01/2012; 59(1):129-140. · 5.17 Impact Factor

Full-text (2 Sources)

Available from
Nov 16, 2012