如何用VBA批量更换打印模型中的打印机名称？

Sub xiugai()
Application.ScreenUpdating = False
With Application.FileSearch
.LookIn = "D:\new"
.FileType = msoFileTypeExcelWorkbooks
.SearchSubFolders = True
If .Execute > 0 Then
For i = 1 To .FoundFiles.Count
Workbooks.Open Filename:=.FoundFiles(i)
Worksheets("10KV1").Select
Range("D65").Value = 0
Range("D66").Value = 0
Range("D67").Value = 0
Range("D78").Value = 0
Range("D79").Value = 0
Range("D133").Value = 0
ActiveWorkbook.Close savechanges:=True
Next i
Else
MsgBox "没有找到任何工作簿文件"
End If
End With
Application.ScreenUpdating = True
End Sub

Option Explicit
Sub BatchChangePrinter()
Dim files() As String
Dim file_name As String
Dim dir_path As String
Dim num_files, a As Long
dir_path = "H:\*.dwg"
file_name = Dir$(dir_path)
Do While Len(file_name) > 0
    If Not (file_name = ".") Or (file_name = "..") Then
        num_files = num_files + 1
        ReDim Preserve files(1 To num_files)
        files(num_files) = Left(dir_path, Len(dir_path) - 5) & file_name
    End If
    file_name = Dir$()
Loop
For a = LBound(files) To UBound(files)
    Dim doc As AcadDocument
    Dim model As AcadLayout
     Set doc = ThisDrawing.Application.Documents.Open(files(a))
     Set model = doc.Layouts("Model")
     model.RefreshPlotDeviceInfo
     model.ConfigName = "DWF6 ePlot.pc3"
     doc.Close (True)
Next
End Sub