Create Substation and Voltage using C# code

m_Project = m_Selection.NewChild(ObjectKind.Project);
m_Project.Attributes.FindById(AttributeId.Designation).Value = project.Name; m_Project.Store();

Above is the code I have used for creating project after reading the xml. I need to do the same for creating the substation and volatages and typical unit.
I can find the typical unit in ObjectType with typeId = 14 but I cannot find the Substation and Voltage(Board) in either ObjectKind or ObjectType with typeIds 15 and 16 respectively. Please help me on how I can create the substation and voltages using C# code.