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A new optimisation-based modulation and control design for matrix converters is proposed. The design uses a quadratic optimisation programme to seamlessly combine control requirements on the input and output sides of the converter. On the input side, the requirements are to keep the source voltage and current in phase with each other and to attenuate transient oscillations caused by a resonant RLC filter, which is used to protect the voltage source from undesirable harmonics. On the output side the requirement is to track a desired current to feed a load. The novel aspects of the scheme are that (i) the optimisation is posed in terms of the converter's modulation matrix, whose entries represent the duty cycles of each of the converter switches; and that (ii) the solution of the optimisation is obtained in closed form and shown to be implementable with a small number of elementary operations. Simulation results demonstrate the good performance of the proposed design. [ABSTRACT FROM AUTHOR]

The Matrix Converter is a power electronics topology that allows direct conversion of an alternating-current (AC) source to an AC load operating at a different frequency. The associated control problem is inherently difficult since it is both nonlinear and underactuated. This paper describes a novel control strategy for Matrix Converters based on Transient Power Balance. The scheme achieves the following design objectives: tracking of a desired load current, tracking of a desired supply (leading or lagging) power factor, rapid active damping of supply-current oscillations, arising from a supply-side resonant filter, without needing any additional resistance on the supply side, and mitigation of supply-current distortion arising from supply-voltage distortion. Achieving these goals simultaneously has hitherto been an open problem in this area. All of these goals are achieved in the face of significant errors in circuit component values. A proof of local asymptotic stability of the proposed algorithm is given and associated design constraints are addressed. The claims are illustrated by simulation studies. [ABSTRACT FROM AUTHOR]

Open-loop poles on, or near, the imaginary axis in the complex plane are a common occurrence in feedback systems. They can occur as part of the model in systems containing lightly damped resonances or they can be deliberately introduced so as to ensure perfect tracking for sinusoidal or periodic signals. This paper establishes both time and frequency domain implications of such poles on system performance. Dual results for zeros on, or near, the imaginary axis are also discussed. Many practitioners are, at least heuristically, aware of the broad implications of these results but, to the best of the authors' knowledge, they have not previously been explicitly articulated nor quantified. [ABSTRACT FROM AUTHOR]

Abstract: Control technology underpins the operation of many, and arguably all, modern high technology systems. Such systems include transportation (aircraft, high speed trains, marine vessels, automobiles), telecommunication systems, electricity networks, mining, minerals processing and agriculture. A particular area where control is playing an increasingly important role is industrial electronics. In this paper we will give a tutorial introduction to the application of control engineering concepts to such systems and reflect on the opportunities and challenges that exist in this area. [ABSTRACT FROM AUTHOR]