The matrix converter is an array of controlled semiconductor switches that connects directly the three-phase source to the three-phase load. This converter has several attractive features that have been investigated in the last two decades. In the last few years, an increase in research work has been observed, bringing this topology closer to the industrial application. This paper presents the state-of-the-art view in the development of this converter, starting with a brief historical review. An important part of the paper is dedicated to a discussion of the most important modulation and control strategies developed recently. Special attention is given to present modern methods developed to solve the commutation problem. Some new arrays of power bidirectional switches integrated in a single module are also presented. Finally, this paper includes some practical issues related to the practical application of this technology, like overvoltage protection, use of filters and ride-through capability.

Matrix converters: a technology review

Analysis, design, and implementation of the space vector modulated three-phase to three-phase matrix converter with input power factor correction are presented. The majority of published research results on the matrix converter control are given an overview, and the one which employs simultaneous output-voltage and input-current space vector modulation, is systematically reviewed. The modulation algorithm is theoretically derived from the desired average transfer functions, using the indirect transfer function approach. The algorithm is verified through implementation of a 2 kVA experimental matrix converter driving a standard induction motor as a load. The switching frequency is 20 kHz. The modulator is implemented with a digital signal processor. The resultant output voltages and input currents are sinusoidal, practically without low-frequency harmonics. The input power factor is above 0.99 in the whole operating range.

Space vector modulated three-phase to three-phase matrix converter with input power factor correction

In this paper, a novel representation of the switch state of a three-phase to three-phase matrix converter is presented. This approach, based on space-vector notation, simplifies the study of the modulation strategies, leading to a complete general solution of the problem and providing a very useful unitary point of view. The already established strategies can be considered as particular cases of the proposed general solution. Using this approach, it can be verified that the space-vector modulation technique, owing to the intrinsic two degrees of freedom, represents the general solution of the modulation problem of matrix converters. This technique can be considered the best solution for the possibility to achieve the highest voltage transfer ratio and to optimize the switching pattern through a suitable use of the zero configurations.

Matrix converter modulation strategies: a new general approach based on space-vector representation of the switch state

A novel three-phase ac-ac sparse matrix converter having no energy storage elements and employing only 15 IGBTs, as opposed to 18 IGBTs of a functionally equivalent conventional ac-ac matrix converter, is proposed. It is shown that the realization effort could be further reduced to only nine IGBTs in an ultra sparse matrix converter (USMC) in the case where only unidirectional power flow is required and the fundamental phase displacement at the input and at the output is limited to plusmnpi/6. The dependency of the voltage and current transfer ratios of the sparse matrix converters on the operating parameters is analyzed and a space vector modulation scheme is described in combination with a zero current commutation method. Finally, the sparse matrix concept is verified by simulation and experimentally using a 6.8-kW/400-V very sparse matrix converter, which is implemented with 12 IGBT switches, and USMC prototypes.

Novel Three-Phase AC–AC Sparse Matrix Converters

This paper presents a review of the current state of the art in terms of practical matrix converter technologies. Present solutions to the numerous technological issues and challenges faced when implementing viable matrix converters are discussed. The reported use of the matrix converters in different applications is also presented together with a review of current industrial applications.

Technological Issues and Industrial Application of Matrix Converters: A Review

The maximum input-output transformer ratio, or output voltage ability, of direct AC-AC pulse-width-modulated converters is explored. An intrinsic limit, independent of the control algorithm, is found. A suitable novel converter control algorithm is discussed which achieves such maximum output amplitude ability and displays some interesting features. Finally, the opportunity to implement AC-AC converter control with the use of feedback techniques is considered, and a feedback-based control algorithm for the converter is proposed. >

M.G.B. Venturini

Papers

Analysis and design of optimum-amplitude nine-switch direct AC-AC converters