Grid-Forming Control Based On Emulated Synchronous Condenser Strategy Compliant With Challenging Grid Code Requirements

TL;DR

This paper introduces a novel grid-forming control strategy based on emulating a synchronous condenser, capable of meeting challenging grid code requirements such as fault ride-through and black start, demonstrated through simulation of a battery energy storage system.

Contribution

It proposes a unified GFM control approach that emulates a synchronous condenser with explicit swing equation representation, handling various grid disturbances without additional logic.

Findings

Successfully manages severe grid disturbances in simulations

Handles fault ride-through and black start with a single control structure

Demonstrates robustness in high inverter-based generation scenarios

Abstract

Future power systems will include high shares of inverter-based generation. There is a general consensus that for allowing this transition, the Grid-Forming (GFM) control approach would be of great value. This article presents a GFM control strategy which is based on the concept of an Emulated Synchronous Condenser in parallel with a controlled current source with an explicit representation of the swing equation. The advantage of this control is that it can cope with challenging grid code requirements such as severe phase jumps, balanced and unbalanced Fault Ride-Through (FRT), main grid disconnection and black start. All these scenarios can be surpassed with a single control structure with no further logic involved (e.g. fault detection to turn on or off different control parts, freezes, etc.). The proposed strategy is evaluated via time-domain simulations of a 2-MW Battery Energy Storage System (BESS).