This PowerShell script merge several CSV files in just one. All CSV files must have the same headers and in the same order to be effective.

Merge-CsvFiles.ps1

param(
    [Parameter(Mandatory=$true)]
    [String] $Location,

    [Parameter(Mandatory=$true)]
    [String] $NameFilter,

    [Parameter(Mandatory=$true)]
    [String] $OutputFile
)

If(Test-Path $OutputFile) {
    Remove-Item $OutputFile -Force
}

# Writing headers obtained from the first file found
Get-ChildItem -Path $Location -Filter "$NameFilter.csv" 
    | Select -First 1 
    | Get-Content 
    | Select -First 1 
    | Out-File $OutputFile -Append

# Writing content for each file
Get-ChildItem -Path $Location -Filter "$NameFilter.csv"
    | Foreach {
        $_ 
            | Get-Content
            | Select -Skip 1
            | Out-File $OutputFile -Append
    }