# Load WinSCP .NET assembly
Add-Type -Path "C:\Program Files (x86)\WinSCP\WinSCPnet.dll"
# Set up session options
$sessionOptions = New-Object WinSCP.SessionOptions -Property @{
    Protocol = [WinSCP.Protocol]::Sftp
    HostName = "ip_sftp_server"
    UserName = "username"
    Password = "password"
    SshHostKeyFingerprint = "ssh-rsa 2048 =***"
}
$session = New-Object WinSCP.Session
try
{
    # Connect
    $session.Open($sessionOptions)
    # Transfer files
    $session.PutFiles("C:\Users\admin\Desktop\test.txt", "/remote_folder/*").Check()
}
finally
{
    $session.Dispose()
}