Tesis Doctorado
Predictive control in an indirect matrix converter
Author
Ribera-Abarca, Marco Esteban
Institutions
Abstract
The indirect rnatrix converter has been the subject to investigation for some time. One of the favorable features of this con verter is the absence of a de-link capacitar, which allows for the construction of compact converters capable of operating at adverseatmospheric conditions such as extreme temperatures and pressures. Thesefeatures have been explored extensively and are the main reasons why the matrixconverters family has been investigated for decades. The indirect matrix converter features an easy to implement and secure commutation technique, the de-link zero current commutation. Moreover, the conventional indirect matrix converter has bidirectional power flow capabilities and it can be designed to have small sized reactive elements in its input filter. These characteristics make the matrix converter a suitable technology for high efficiency converters for specific applications such as military, aerospace, wind turbine generator system, external elevators forbuilding construction and skin pass mill, where these advantages make up forthe additional cost of an indirect matrix converter compared to conventional converters. This converter uses complex pulse width modulation and space vectormodulation schemes to achieve the goal of unity displacement power factor andsinusoidal output current. Thanks to technological advances, fast and powerfulmicroprocessors are used for the control and modulation of power converters.To deal with the high processing power needed for these microprocessors, someresearch has shown the positive potential of model-based predictive control techniques in many power electronics applications. While there are a few challenges to the predictive control method, it has been demonstrated as an appealing alternative to power converters control because its concepts are very intuitive and easy to understand, and it can be applied to a wide variety of systems. In addition, it may involve multiple variable systems and non-linear constraints, making it an easy controller to implement, especially since it is open to modifications and extensions for specific applications. Predictive current control can be described as a particular case of model-based predictive control which takes into account the inherent discrete nature of the switching states of the power converter and the digital implementation. JVIost of predictive current control methods appliedin matrix converters take into consideration the output current regulation and the reactive power minimization on the input side, obtaining input currents in phase with their respective phase voltages. However, this cannot ensure that they present a sinusoidal waveform, especially when harmonic distortion in the sourcevoltage or strong resonances on the input filter are present. To enhance the quality of the source current, in this document is illustrate how the predictive current control can be applied to an indirect matrix converter and how both source and load currents waveforms can be controlled. PFCHA-Becas Doctorado en Ingeniería Eléctrica 159p. PFCHA-Becas TERMINADA