The magnetodynamic flow of nonviscous perfectly conducting gas is considered in this paper. It is shown that the application of the method of K. Voronjec allows a theoretical investigation of different kinds of MGD flow. Some solutions for the flow in channels were found, when there is a weak change of the parameters in one way. The method of K. Voronjec is applied for the study of translatory symetrical and three-dimensional MGD flow. This method was extended onto dynamics of perfectly conducting gas and that allows an exact investigation of vorticity MGD flow.