Design And Research On The Control Method Of Bidirectional DC/DC Converter

With the development of human civilization, the demand for electricity in modern society is becoming more urgent than ever. In some applications,the DC/DC converter should have the ability to transfer energy in bidirectional directions. The bidirectional DC/DC converter has been widely used in many fields, such as electric drive, distributed energy,intelligent charging and discharging system and so on. In the condition of polarity unchanged of the input and output voltage,this converter can change the transfer directions of the current.The energy can transfer to both sides of the converter. In the circuit structure, as long as there is a reverse flow of energy in the circuit, then the energy can transfer in both sides.After a lot of reading, theoretical research and analysis, the bidirectional full-bridge DC/DC converter was selected by comparing the topology of typical bidirectional DC/DC converters. A detailed analysis was given on the principle and soft-switching conditions,according to the requirements of the task performance, parameters of the main circuit elements were designed, such as IGBTs, capacitors, inductors and so on. The Sliding Mode Control has been selected by comparing with other control strategies. The design on the sliding surface, sliding on issues such as the selection of the sliding parameters was studied.The simulation model of bidirectional DC/DC converter was built based on simulation software Saber. In order to verify the output insensitivity when there are fluctuations in the external parameters, such as the input voltage and output load fluctuations. The phase-shift control strategy and repetitive control strategy has been used on simulation studies.Finally, based on IGBTs, FPGA chip as a controller, a rated power of 1000W experimental platform was built. In order to verify the design of the converter, the related experimental analysis was carried on.