An example of how to query a PowerBI dataset using Powershell and AdomdClient

Query-PowerBIDataset.ps1

$ErrorActionPreference = "Stop"

function LoadAdomdClientPackage() {
    $package = Get-Package -Name Microsoft.AnalysisServices.AdomdClient.retail.amd64 -ErrorAction SilentlyContinue
    if (!$package) {
        Install-Package -Name Microsoft.AnalysisServices.AdomdClient.retail.amd64 -RequiredVersion 19.61.1.4 -ProviderName NuGet -Source "https://www.nuget.org/api/v2" -Scope CurrentUser -SkipDependencies -Force
        $package = Get-Package -Name Microsoft.AnalysisServices.AdomdClient.retail.amd64
    }
    $assemblyPath = Join-Path (Get-ChildItem $package.Source).DirectoryName "lib\net45\Microsoft.AnalysisServices.AdomdClient.dll"
    try { Add-Type -Path $assemblyPath} catch { $_.Exception.LoaderExceptions }
}

function ExecuteAdomdQuery($connectionString, $query) {
    $connection = New-Object Microsoft.AnalysisServices.AdomdClient.AdomdConnection;
    try {
        $connection.ConnectionString = $connectionString
        $connection.Open();
        $table = New-Object System.Data.DataTable
        $adapter = New-Object Microsoft.AnalysisServices.AdomdClient.AdomdDataAdapter $query, $connection
        $adapter.Fill($table)
        $connection.Close();

        return $table
    }
    finally {
        $connection.Dispose();
    } 
}

#$bearerToken=''
#$databaseId='00000000-0000-0000-0000-000000000000'
#$connectionString = "Provider=MSOLAP;Data Source=pbiazure://api.powerbi.com;Initial Catalog=sobe_wowvirtualserver-$databaseId;Integrated Security=ClaimsToken;Password=$bearerToken" 

$workspaceName='' # use an empty string to connect to "My Workspace"
$databaseName='Contoso-myworkspace'
$connectionString = "Provider=MSOLAP;Data Source=powerbi://api.powerbi.com/v1.0/myorg/$workspaceName;Initial Catalog=$databaseName;" 

LoadAdomdClientPackage;
$table = ExecuteAdomdQuery $connectionString "EVALUATE { 1 }";
$table | Format-Table