Research On A Novel Three-phase AC/DC Converter

In this paper,the three-phase AC/DC converter is studied.In order to improve the efficiency and reduce the control complexity of three-phase AC/DC converter at the same time,two new three-phase AC/DC converter topologies based on Boost and Buck circuits are proposed.The working principle of the new three-phase AC/DC converter topology is analyzed in detail,and the hardware circuit of the system is designed.Meanwhile,the new three-phase AC/DC converters are simulated and verified through experiment study.Firstly,the state of AC/DC conversion system in two aspects of topology structure and control strategy are analyzed.And the work principles of traditional three-phase AC/DC rectifier topology based on Boost and Buck circuits are shown.Then,the analysis and modeling for three-phase voltage-type PWM rectifier are carried out.Secondly,the operation principles of the two new three-phase AC/DC converters,which are based on Boost and Buck circuits are proposed.Then the control strategies of the two new converters are analyzed.By analyzing its engineering principle and control strategy,the system switch state diagram and system control diagram are provided.For the new three-phase buck-type AC/DC converter,two modulation modes are introduced,one of which is triangular carrier modulation and the other is space vector modulation.Then,the simulations of two new three-phase AC/DC converters are carried out.Finally,the hardware design of the new three-phase AC/DC converters is presente d,which contains the design of the peripheral hardware circuit and the auxiliary power supply circuit.Meanwhile,an experiment platform for 800 W three-phase boost-type rectifier and another experiment platform for 10 KW three-phase Buck-type rectifier are set up respectively.For the experiment AC/DC converter platforms,the voltages,currents and driving waveforms of the two new topologies are experimentally verified.And the efficiency curves of two new three phase AC/DC converters are obtained according to the experiment data.The results of simulations and experiments have verified the effectiveness and feasibility of the proposed two novel three-phase AC/DC converter topologies.