The subtransient and fast transient system characteristics of conventional power systems based on synchronous-generator feed in are dominated by the physical electrical equations of rotating machines and comparable slow exciter control and technology control loops. In contrast, the introduced fast system characteristics of modern grids including various converter-based infeed and load assets are dominated by algorithms which aim to satisfy grid-code requirements in specific countries. To achieve an adequate security of supply, an enormous increase in compliance testing is a must. To master this challenge with the necessary quality with acceptable costs and resource requirements, an automated compliance testing is a must.

The novelties cover two dimensions: On the one hand side, automated assessment is extended for converter assessments covering all adequate requirements to determine trustful results. On the other hand, the automated assessment is extended to transient and subtransient assessments by utilizing dynamic envelope curves based on the actual grid states – e.g. positive and negative sequence fundamental voltage as well es frequency. Furthermore, live-model estimation in the scope of converter properties like e.g. transient behaviour as well as voltage-forcing properties is a new topic.

Within this paper, an approach to achieve consistent automated compliance testing and model validation for grid planning, project execution and system operation is presented and backed by measurement, HIL and simulation assessments of commercial projects. The assessment algorithms are formulated in a neutral high-level language in order to be able to use the algorithms on different operating systems and in FPGA utilizing code generation and sophisticated interpreters. Based on this neutral formulation, assessment algorithms can be improved in standard commercial grid-calculation tools like e.g. PSCAD, PowerFactory, ATP, VIAvento and deployed to field-measurement devices in a consistent way. Furthermore, the algorithm can be integrated in modern system-operation platforms ever so often built in Kubernetes clusters, e.g. for ex-post analysis or dynamic security assessment. Additionally, results of the model estimation of real assets are given.

A special focus is on the realization of an adequate converter assessment covering not only the steady-state behaviour but also subtransient and transient responses as well as harmonic emissions. Results will be showcased utilizing a weak grid-connection scenario with generic data due to restrictions on vendor IP in the real setup. Field measurement results from commercial projects are given and compared with simulation results.