Dynamic Solar Hosting Capacity Calculations in Microgrids

TL;DR

This paper investigates the dynamic hosting capacity of solar PV in microgrids, highlighting the importance of dynamic analysis over steady-state methods to accurately determine integration limits and ensure operational stability.

Contribution

It introduces a dynamic approach to hosting capacity calculations for microgrids, emphasizing the need for detailed simulations during mode transitions.

Findings

Dynamic analysis reveals lower hosting capacity limits than steady-state methods.

Simulations demonstrate the impact of PV penetration on microgrid stability.

Operational risks can be mitigated by understanding dynamic hosting constraints.

Abstract

Microgrids, as small-scale islandable power systems, are considered as viable promotors of renewable energy resources. In particular, microgrids can efficiently integrate solar photovoltaic (PV) as the deployment of this customer-deployed technology is growing in distribution grids. However, there is a limit on how much PV can be hosted by a microgrid. High penetration of PVs can potentially put the microgrid at operational risks including but not limited to over and under voltages, excessive line losses, overloading of transformers and feeders, and protection failure. To avoid such potential negative impacts, the concept of hosting capacity is introduced and used. The hosting capacity is defined as the total capacity of DERs that can be integrated into a given feeder/microgrid without exceeding operational restrictions and/or requiring system upgrades. Hosting capacity studies are primarily done based on steadystate analyses. However, in case of microgrids and when transitioning between grid-connected and islanded modes, dynamic operation becomes more restrictive than steady-state operation and thus is worthy of detailed investigation to provide a better understanding of the amount of DER that the microgrid can host. This paper examines this problem and provides extensive simulations on a practical test system to show its importance and merits.