Research And Design Of Bidirectional DC/AC Converter For V2G

Bidirectional DC/AC converters occupy an important position in the field of new energy power generation.With the continuous development of power electronics technology,the requirements for bidirectional DC/AC converters are also increasing,and the bidirectional DC/AC converters are gradually moving toward Miniaturization and integration are developing.With the increasing number of electric vehicles,the idle electric vehicles can feed back energy to the grid.Combined with V2 G technology,this paper has conducted in-depth research on the bidirectional DC/AC converter for V2 G.The main research contents are as follows:Designed the topology of the main circuit of the system,and the four working modes of the bidirectional DC/AC converter are analyzed.According to the experimental requirements,the filter of the bidirectional DC/AC converter is designed and applied to the main circuit.The inductance and capacitance parameters were analyzed and estimated.The parameters of the power tube were selected.The design of the phase-locked loop in the main circuit is also analyzed.Studied the control strategy of the bidirectional DC/AC converter.Firstly,the space vector modulation algorithm of three-phase four-leg circuit is analyzed,and the three-dimensional space vector modulation strategy in abc coordinate system is selected.Includes mathematical modeling of 3D vectors,sector determination of 3D vectors,and how to synthesize PWM signals.Combined with the relevant functional requirements,the control strategy of the bidirectional DC/AC converter in rectification mode and inverter mode is designed.The control strategy of proportional resonance based on fuzzy control in abc coordinate system is proposed.And the feasibility of the control strategy is verified in the simulation.Designed The control circuit and software program of the bidirectional DC/AC converter.The control chip of the control circuit is selected and the minimum system circuit of the chip is designed.The acquisition circuit of the control circuit is designed,including the acquisition circuit parameter design and the hardware protection circuit design.The drive circuit has also been designed.Finally,the design of the software program,including the main program design,interrupt subroutine design,etc.Finally,the physical platform was built and tested on a 10 kW bidirectional DC/AC converter prototype.The feasibility of the control strategy was verified,and the prototype was able to operate normally and stably.The parameters of the parameters also met the design requirements.