Engineering Design And Application Of Power Electronic Transformer

Power Electronic Transformer(PET) is a new intelligent power transformer, which as a combination of transformer and power electronic technology development, it not only overcomes the traditional transformer's some inherent defect, but also environmental protection, energy saving, harmonic suppression, fault isolation and power quality control, operation control, the advantages of stability control, make it have potential to solve many new problems in the development of modem power system, along with the smart grid and renewable energy technology development, on the basis the development of the power electronic converter technology and power electronic device that Power Electronic Transformer will be got long attention and further research in the related fields of power system at home and abroad in the future.This paper mainly introduces the actual engineering design and application of power electronic transformer. Firstly, the cascaded H bridge structure, principle and control strategy of power electronic transformer are introduced, analyzes the cascade PWM rectifier bridge module, DC-DC link with high frequency isolation transformer and structure principle of inverter output stage, modeling and puts forward the relevant control strategy, simulation verified the PET ability to resist disturbance is strong, the whole system has good performance.Secondly, in this paper aiming at the main circuit of power electronic transformer parameter design, and according to the selection and design of the main circuit parameters for the device is introduced. Also the design of power electronics cabinet is introduced, which switchgear, power unit and control cabinet was introduced in detail about the components of the layout, especially for the design of the power unit cabinet's rectifier stage install ark, isolation link install ark and inverter installation cabinet structure.Thirdly, aiming at the problem that power electronic transformer faces some actual engineering design difficulties are analyzed in detail, and corresponding solutions are given, which in the design of the actual power electronic transformer has very realistic significance. For control system using DSP+FPGA digital controller as the control core, this paper introduces the voltage phase detecting circuit, sampling circuit, fault protection circuit of hardware circuit, and introduces the different module's program design of DSP and FPGA.Finally, the PET requirements for the test in the practical engineering application, loss calculation has carried on the brief introduction in the paper, system debugging results showed that the circuit design meets the requirements, control system design is reasonable, the system is stable and meet the design requirements of PET.