Экспорт данных из DataGrid в Excel [требует правки]

Необходимо вывести данные DataGrid в Excel. Слетает кодировка.

XAML DataGrid:

<DataGrid AutoGenerateColumns="True" x:Name="DataGridView1"  Grid.Row="0" Grid.ColumnSpan="7" SelectionChanged="DataGridView1_SelectionChanged" >
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding ID_document}" Header="Код документа" Width="100"/>
        <DataGridTextColumn Binding="{Binding NumberDocument}" Header="Номер документа" Width="100"/>
        <DataGridTextColumn Binding="{Binding Articul}" Header="Артикул" Width="100"/>
        <DataGridTextColumn Binding="{Binding DateDocument}" Header="Дата составления" Width="100"/>
        <DataGridTextColumn Binding="{Binding Predpriyatie}" Header="Предприятие" Width="100"/>
        <DataGridTextColumn Binding="{Binding ID_kinddocument}" Header="Код вида документа" Width="100"/>
        <DataGridTextColumn Binding="{Binding Photo}" Header="Ссылка на файл" Width="100"/>
    </DataGrid.Columns>
</DataGrid>

Код заполнения C#:

DataTable RabTable = new DataTable();
SqlConnection connection = Connector.Connection(@"MSI\SLAVABELIYRASSE", "sa", "3885895w", "DIPLOM_BASE");
SqlCommand select_rab = new SqlCommand("select ID_document ,NumberDocument ,Articul ,DateDocument,Predpriyatie ,Document.ID_kinddocument ,Photo  from Document join  KindDocument on KindDocument.ID_kinddocument= Document.ID_kinddocument", connection);//WHERE NumberDocument LIKE '%" + txtbx_date_Copy.Text + "%' or ID_document LIKE '%" + txtbx_date_Copy.Text + "%' " + txtBx_Dogovor.Text +"%'", connection);
connection.Open();
SqlDataReader rd = select_rab.ExecuteReader();
RabTable.Load(rd);
rd.Close();
DataGridView1.DataContext = RabTable.DefaultView;
DataGridView1.ItemsSource = RabTable.DefaultView;
DataGridView1.AutoGenerateColumns = true;
connection.Close();