$vmName = "vm01"
$vm = Get-VM -Name $vmName -ErrorAction Stop
$vm |Stop-VM -Force -ErrorAction Stop
while($vm.Heartbeat -like "Ok*") {
    Start-Sleep -Seconds 1
}
Write-Host "$($vm.Name) is Off. Start VM..."
$vm = Get-VM -Name $vmName -ErrorAction Stop
$vm |Start-VM -ErrorAction Stop
while($vm.Heartbeat -notlike "Ok*") {
    Start-Sleep -Seconds 1
}
Write-Host "$($vm.Name) is Rebooted."