This runs the SharePoint Health Analysis Job manually.
Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue
#Display name of the Timer Job to Run on-demand
$TimerJobName = "Health Analysis Job"
#Get the Timer Job
$TimerJobs = Get-SPTimerJob | where { $_.DisplayName -match $TimerJobName}
foreach($TimerJob in $TimerJobs)
{
Write-Host "Running:" $TimerJob.DisplayName
$TimerJob.RunNow()
#$TimerJob.Status
}