Study On A Novel PMSM Control Technology

Since the 1980's till now, with the permanent magnetic material cost reduction and performance improvement and the development of power electronic technology, computer technology and automatic control theory , the PMSM control technology research has entered a new stage. At present, the PMSM control system is widely used in various industrial field, therefore the research for high-performance PMSM control technology has a very important theoretical significance and practical value.Three-phase four-leg inverter in motor control areas usually applied to fault-tolerant techniques. In those applications, the fourth leg is only used in the post-fault operation aiming to replace a faulty leg or allowing a neutral current to flow. But actually, the applicaton of four-leg inverter can also make the PMSM gain a good control performace in the unfaulty mode of operation as well , This is the reason why this paper mainly researches the PMSM control technology with three-phase four-leg inverter topology.First, this paper illustrates the mathematic PMSM model with connected neutal point, researches the PMSM vector control principle and current control method, analyses the three-phase four-leg principle of inverter,and proposes the three-phase four-leg of the PMSM vector control strategy. Then, the 3D-SVM has been studied and the 3D-SVM basic principle and the implementation method are elaborated in detail.Simulation experiment has been done by using the Matlab/Simulink software. The concrete scheme of the 3D-SVM is presented and the validity is proved; and then the simulation module of the PMSM with connected neutral point vector control system is established and a lot of simuliation experiments has been done to confirm the theoretical analysis is correct. Finally the experimental platform is established by using DSP 2812 as the control chip to verify the feasibility of the system.The content studied in this paper has a significant meaning for three-phase four-leg inverter's application in PMSM control.