loop start a site workflow on sharepoint online using powershell csom

startsiteworkflow.ps1

#Add references to SharePoint client assemblies and authenticate to Office 365 site - required for CSOM
Add-Type -Path “C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\ISAPI\Microsoft.SharePoint.Client.dll”
Add-Type -Path “C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\ISAPI\Microsoft.SharePoint.Client.Runtime.dll”
Add-Type -Path “C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\ISAPI\Microsoft.SharePoint.Client.WorkflowServices.dll”

#Specify tenant admin and site URL
$SiteUrl = "mysiteurl"
$UserName = "myusername"
$SecurePassword = ConvertTo-SecureString "mypassword" -AsPlainText -Force

#Bind to site collection
$ClientContext = New-Object Microsoft.SharePoint.Client.ClientContext($SiteUrl)
$credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($UserName, $SecurePassword)
$ClientContext.Credentials = $credentials
$ClientContext.ExecuteQuery()

# Create WorkflowServicesManager instance
$WorkflowServicesManager = New-Object Microsoft.SharePoint.Client.WorkflowServices.WorkflowServicesManager($ClientContext, $ClientContext.Web)

# Connect to WorkflowSubscriptionService
$WorkflowSubscriptionService = $WorkflowServicesManager.GetWorkflowSubscriptionService()

# Connect WorkflowInstanceService instance
$WorkflowInstanceService = $WorkflowServicesManager.GetWorkflowInstanceService()

$ClientContext.Load($WorkflowServicesManager)
$ClientContext.Load($WorkflowSubscriptionService)
$ClientContext.Load($WorkflowInstanceService)
$ClientContext.ExecuteQuery()

# Get Site Workflows
$SiteWorkflows = $WorkflowSubscriptionService.EnumerateSubscriptions()
$ClientContext.Load($SiteWorkflows)
$ClientContext.ExecuteQuery()
$SiteWorkflows | Select Id, Name, StatusFieldName | FT -AutoSize

# Define Site Workflow
$SiteWorkflowID = 'mysiteworkflowid'
$SiteWorkflow = $WorkflowSubscriptionService.GetSubscription($SiteWorkflowID)
$ClientContext.Load($SiteWorkflow)
$ClientContext.ExecuteQuery()

# Prepare Start Workflow Payload
$Dict = New-Object 'System.Collections.Generic.Dictionary[System.String,System.Object]'

# Loop Start Workflow
For ($j=0; $j -lt 10; $j++){
  $Action = $WorkflowInstanceService.StartWorkflow($SiteWorkflow, $Dict)
  $ClientContext.ExecuteQuery()

  # Get Workflow Status
  $WorkflowInstance = $Action.Value
  $WorkflowStatus = $WorkflowInstanceService.GetInstance($Action.Value)
  $ClientContext.Load($WorkflowStatus)
  $ClientContext.ExecuteQuery()
  Write-Host $Action.Value $WorkflowStatus.Status
}