Research And Realization Of Three-phase-three-phase Two-stage Matrix Converter

Two-stage matrix converter(TSMC), due to, in addition to have controllable input power factor to be one, sinusoidal input and output, wide adjustment range of output frequency and four-quadrant operation as Matrix Converter(MC), but also have a simple modulation strategy, commutation strategy and clamp circuit, has become a great potential AC-AC direct power converter. This paper undertakes a study around the three-phase-three-phase TSMC topology, as well as modulation strategies, common-mode voltage restraining, simulation verification and 3kw prototype design of three-phase-three-phase 18 switches TSMC.Bi-direction switch is a premise for the development of MC and TSMC. The comparison of different bi-direction switch structures in TSMC's rectifier-level are analysed. The equivalence of the MC and TSMC can be find by transfer matrix derivation, it has proved the MC and TSMC sharing the same frequency performance. Under the different constraints, the simplify process among the basic topology, 18 switches, 15 switches, 12 switches and 9 switches of TSMC are given, also the other inverter-level structure of the TSMC and their research purposes are given.The principle of doulbe space vector modulation(DSVM) with 18 switches TSMC is analysed, which contain the none-zero vector and zero vector in the rectifier-level. The purpose of the two-stage coordination modulation and two-stage commutation strategy with rectifier-level and inverter-level are to achieve the output voltage constant and safe commutation. The two-stage commutation contain the zero-current commutation of rectifier-level and dead commutation of inverter- level. The Matlab/Simulink simulation model and simulation waveforms are given. For the existence of common-mode voltage in TSMC, combining with the distribution of TSMC common-mode voltage, an improved DSVM is proposed, which has ensure the zero-current commtation of rectifier-level, and achieve the purpose of common-mode voltage suppression. The simulation verification with Matlab/Simulink is given.On the basis of the theoretical analyse, a 3kw 18 switches TSMC prototype which base on none-zero vector of rectifier-level is developed. Details of the main circuit switches device, snubber circuit, input filter and clamp circuit's parameter design are introduced. The combination of DSP and CPLD control system design is given ,in which, the DSP realize the algorithm of DSVM, and the CPLD achieve the signal decoding, two-stage commutation and the PWM drive signal output. The simulation waveforms which base on Quartus II are obtained. The cause, effect and solution of little-duty within software design are analysed. The device-level, system-level, common-mode voltage with the unimproved and improve DSVM experiment waveforms are obtain from the prototype.Through the simulation and experiment, they are verify the 18 switches TSMC has an excellent frequency performance, and the adoption of improved DSVM reaches the purpose of common-mode voltage suppression.