This paper introduced the connection plan of the new type converter transformer and filter as well as the design characteristic of the filter.The filter’s mathematical optimization model taken the minimum investment as target function was created.This paper adopted the mixed penalty function method changing the restraint problem to the object function with penalty without restraint

when using the genetic algorithm to optimize the model and considering the characteristic of the model.At last

aiming at the specific new type HVDC’s platform

an example of the optimization of filter was given.The results of the example prove correction of the optimization design.