Research On Matrix Converter And Its Applica-tion In Motor Drive

Matrix converter is a new kind of AC-AC power converter, it has a lot of advantageswhich are different from the traditional AC-DC-AC converter, such as: it has low harmonicdistortion and high power factor; it doesn’t require energy storage devices, so it has a smallsize and excellent dynamic performance; it’s output voltage amplitude, frequency, phaseand input power factor can be independently controlled; the energy in the matrix convertercan flow to bi-direction easily, so the motor can operate in four-quadrant. With the rapid de-velopment of power electronics technology, it has become a hot topic in the power converter.The research background and current situation of matrix converter are analyzed in thispaper. The3×3matrix converter is chose as the research object, and much research on the ba-sic principles and pivotal technologies of matrix converter including modulation methods andcommutation strategies are accomplished, then, based on the analysis of matrix con-verter principles and technologies, the system structure and the hardware platform are estab-lished, the indirect space vector modulation method and the four-step commutation strat-egy based on voltage detection are realized on the hardware platform. After realizingthe basic algorithm, the input filter is design to ensure the system has a low harmonic distor-tion; the over current protection circuit and the over voltage snubber circuit are designedto guarantee the safety of elements.In order to verify the performance of the matrix, the basic waveforms of matrix converterare analyzed, experimental results show that matrix converter has sinusoidal input and out-put waveforms and unity power factor; in addition, it has adjustable voltage ampli-tude, frequency and phase. To study the practicality and application prospects of matrix con-verter, induction motor governing systems fed by matrix converter including a variable volt-age variable frequency system, a vector control system based on the rotor field orientation anda direct torque control system are built, and the static and dynamic performance and energytransfer capabilities are analyzed, experimental results show that induction motor governingsystems fed by matrix converter have a good speed tracking performance and a fast torqueresponse.