根据您的代码片段，我添加了Resource Owner Password Credentials流，也称为password流。

private static void ConfigureOuathAuthentication(IServiceCollection services, OuathAuthenticationConfiguration ouathAuthenticationConfiguration)
{
    services.AddAccessTokenManagement(options =>
    {
        options.Client.Clients.Add("identityserver", new ClientCredentialsTokenRequest
        {
            Address = ouathAuthenticationConfiguration.Address,
            ClientId = ouathAuthenticationConfiguration.ClientId,
            ClientSecret = ouathAuthenticationConfiguration.ClientSecret,
            Scope = ouathAuthenticationConfiguration.Scope, // optional
            GrantType = ouathAuthenticationConfiguration.GrantType
        });
    });

    options.Client.Clients.Add("resource-owner", new UsernamePasswordTokenRequest
    {
        Address = "address-for-resource-owner-client",
        ClientId = "clientid-for-resource-owner-client",
        ClientSecret = "clientsecret-for-resource-owner-client",
        Scope = "scope-for-resource-owner-client",
        UserName = "your-username",
        Password = "your-password",
        GrantType = "password"
    });

    services.AddClientAccessTokenHttpClient("client_ouath", configureClient: client =>
    {
        client.BaseAddress = new Uri(ouathAuthenticationConfiguration.Address);
    });
}

如果您有一个有效的身份提供者支持它，并且提供了适当的参数，那么它应该可以工作。