Novel Real-Time EMT-TS Modeling Architecture for Feeder Blackstart Simulations

TL;DR

This paper introduces a novel real-time EMT-TS modeling architecture for distribution feeder restoration, including a testbed with a grid-forming unit in EMT domain and benchmarking against an EMT model.

Contribution

It presents the first real-time EMT-TS testbed with a grid-forming unit in EMT domain, and develops a co-simulation framework for distribution feeder restoration studies.

Findings

High accuracy maintained for load steps with BESS as grid-forming unit

Effective domain coupling methodology demonstrated

Benchmarking shows reliable transient performance

Abstract

This paper presents the development and benchmarking of a novel real-time electromagnetic-transient and transient-stability (EMT-TS) modeling architecture for distribution feeder restoration studies. The work presents for the first time in the literature a real-time EMT-TS testbed in which the grid-forming unit is simulated in EMT domain, operating as the slack bus of the phasor domain while including unbalanced voltage conditions. To evaluate the performance and limitations of the proposed model, an equivalent EMT testbed is developed to serve as a benchmark. First, the co-simulation framework and the domain coupling methodology are introduced. Next, the steady-state operation of the EMT-TS and EMT models are matched. Then, tests are conducted to analyze the transient performance of the proposed EMT-TS model when compared to its EMT benchmark. Results reveal that when utilizing a battery energy storage system (BESS) as the grid-forming unit, the EMT-TS testbed can maintain high accuracy for typical load steps.