Power Electronic System Integration-Motion Control Blocks And Its System Integration

Power electronics system integration, which promotes the development of power and industry automation, is a new direction in future power electronics. Motion control system is a particular branch of power electronic systems, although it is similar to other power electronic systems, it has its own specialties. Under such a background, this dissertation proposes distributed control architecture, communication model and software integration for power electronics system integration, and it presents parallel converters system and multi-phase motor motion control system based on building blocks and system integration. Some meaningful conclusions have been obtained.According to the requirement of power electronic integrated system, distributed and hierarchical control architecture was discussed, and its communication model was put forward based on OSI model, as well as the mapping relationship between control architecture and communication model was analyzed. With mapping to communication model, layers of architecture are clearly defined, which aren't closely related to each other, and easy to upgrade and expand. Basic structures of control architecture were concluded by comparing their characteristics, disadvantages and application fields.By comparative analysis, it was indicated that dataflow style and object-oriented dataflow style are proper software architectures for distributed power conversion systems. Programming criterions of dataflow style, based on DSP, were concluded. The theory of object-oriented dataflow style and its application in software programming of distributed motion control system were introduced. A method named incremental design process was presented for object-oriented dataflow style. A typical V/f control for induction motor was used to verify advantages and application of the presented method. It is of great significance for power conversion software integration design designed or programmed with the method of object-oriented dataflow style by common programming criterions.Parallel operation of multi-converters built with system integration concept, was preliminarily studied. Parallel diode rectifier blocks were investigated, and current sharing strategy was presented to restrain circulating current. Parallel inverter blocks were investigated too, and the concept of "uniform modulation" was proposed while analyzing the circulating current problem. It has been concluded that there is no circulating current among parallel inverter blocks when their unattached output currents have the same frequency, phase, amplitude and uniform modulation. Active and reactive circulating current restrain were discussed respectively, and auto-master-slave synchronization control strategy for parallel operation of inverter blocks was presented. It is of great use that medium/high power converter is built by parallel low power converters with system integration concept.A distributed VVVF control system for six-phase induction motor was based on power drive building blocks and system integration. SPWM control and SVPWM control for distributed control system were discussed respectively; simulation results verified their feasibility. With the same idea, the distributed SPWM/SVPWM control for other multi-phase motor could be realized.The study on parallel converters system and multi-phase motor motion control system shows that motion control system integration is very meaningful in many cases. It is significant and worthwhile to investigate the theory of motion control system integration under the background of power electronics system integration.