Application Research Of Hybrid Two-stage Matrix Converter In Ac Speed-regulating System

As a direct power converter, two-stage matrix converter has many excellent features,such as adjustable unit input power factor, energy bi-directional flow, enabling zero currentcommutation and so on. Hybrid two-stage matrix converter is a new type of matrix convertertopology, which is based on the development of two-stage matrix converter. Hybrid two-stagematrix converter’s voltage transfer ratio is higher than the advantage of two-stage matrixconverter. This is effectively suppress to the influence of input voltage unbalance and loaddisturbance. Hybrid two-stage matrix converter is a converter, that has a good prospect.In the AC speed-regulating system, the permanent magnet synchronous motor is widelyused in various fields of electrical transmission. The characteristics of small size, light weight,simple structure, reliable operation, easy maintenance, high efficiency and energy saving.Meanwhile the velocity-modulation performance of permanent magnet synchronous motorcan compare to DC motors as the application of vector control technologies. So vector controlwill be the best choice for the development of the contemporary electric drive field.The focus of this thesis is to combine the advantages of a hybrid two-stage matrixconverter and apply to permanent magnet synchronous motor drive. Then the hybridtwo-stage matrix is verified. Firstly, there is a detailed analysis of the topology andmodulation strategies of the two-stage matrix converter. And the two-stage matrix converterwill be verified simulate in Matlab/Simulink to prove the validity of the modulation strategy.The further study of hybrid two-stage matrix converter is based on the simulate results.Secondly, there is a detailed analysis of the topology and the modulation strategies at alllevels of the hybrid two-stage matrix converter. The hybrid two-stage matrix converter has astrong ability to suppress the input voltage unbalance which is verified by simulation analysis.The frequency control devices are correct and superior. Then a mathematical model ofpermanent magnet synchronous motor is established and analyzed for vector control strategiesespecially the voltage space vector modulation strategies with this model. Finally, an ACspeed-regulating system model of permanent magnet synchronous motor drive by hybridtwo-stage matrix converter is established for Matlab/Simulink and combined with vectorcontrol technology. Simulations verified that the system has good dynamic and staticcharacteristics as well as stability.