High-Power IGBT Module Design And Module Optimization Based On PCB Laminated Structure

In the power circuit of power electronic equipment and power system,IGBT is widely used.To become a power semiconductor module,multiple power semiconductor chips are packaged in series or parallel according to a certain topology.When the main power chips in the module are IGBT dies,the module is called IGBT module.The main performance of a multi-die in parallel IGBT module has two aspects,one is electrical performance,and the other is thermal performance.The electrical performance is mainly manifested in whether the current distribution between the parallel dies in the module is uniform and the overvoltage generated at both ends of the IGBT die when the module is turning off;the thermal performance is mainly manifested in the maximum temperature of the die in the IGBT module during operation.,in the other hand,the uniformity of temperature distribution in the module is also critical.The electrical and thermal performance of the IGBT module is ultimately affected by the internal layout of the module and the structure of the module.As a small power electronic system with complex structure,how does the internal layout and structure of the IGBT module affect its electrical and thermal performance? There has been a lack of clear analysis methods and analysis steps,so there is no systematic IGBT module design and evaluation process.On the other hand,in the existing structure and frame,the parasitic parameters brought by the traditional IGBT module packaging form are difficult to further reduce,so the traditional packaging structure needs to be improved.In view of the above two problems,this article mainly completed the following work:In the design of the IGBT module,this article first analyzes the parasitic parameters brought by the package structure and the influence of each parasitic parameter on the IGBT die current sharing and turn-off overvoltage.Then,the thermal performance of the IGBT module is analyzed from three aspects,which are heat loss,heat conduction and heat couplition.Then the basic design process is proposed for high-power IGBT design,and a detailed description is given through a 1200V/1600 A high-power IGBT module design example.After the design of the IGBT module according to the design process,an equivalent circuit model will be established.On the basis of this model,the electrical performance of the designed high-power IGBT module was analyzed in three aspects,including static current sharing,dynamic current sharing and shut-off overvoltage.After that,relying on the thermal simulation software,the thermal performance of the module is evaluated in two aspects: the maximum temperature of the die when the module is working and the uniformity of the overall temperature distribution inside the module.Next,this article optimizes the structure of the designed IGBT module.By using PCB to replace the power electrode in the module,the module is designed as a laminated structure as a whole.Simulation verified the feasibility of using PCB to replace the power electrode in terms of current carrying capacity and the optimization effect of the laminated module in terms of electrical performance.The results showed that the parasitic inductance in the module was reduced to 45% of the original.Finally,the previously designed high-power IGBT modules were processed,and the corresponding DC busbars were designed for the processed modules,and related experimental platforms were built at the same time.Through the flow-through experiment test and the shut-off performance test,the thermal performance and electrical performance of the designed high-power IGBT module were verified.