Try something like this
$clusterName="MyCluster"
$path=@()
$cluster=Get-Cluster-Name$clusterName
$parent=Get-View$cluster.ExtensionData.ResourcePool
while ($parent.parent){
$parent=Get-View$parent.parent
$path+=$parent.Name
}
[array]::Reverse($path)
[string]::Join('/',$path)