AC/DC optimal power flow and techno-economic assessment for hybrid microgrids: TIGON CEDER demonstrator

TL;DR

This work develops and validates an AC/DC optimal power flow method for hybrid microgrids alongside a KPI-based techno-economic assessment, enabling simultaneous feasibility analysis and long-term viability evaluation. The method supports four objective functions to tailor operation toward losses, voltage stability, costs, or maximum generation, and is implemented in Python using CasADi and Ipopt. Validation on the TIGON CEDER demonstrator shows close agreement between simulated and measured values, confirming model fidelity. Among four techno-economic scenarios, virtual-battery flexibility delivers the best profitability, highlighting the value of market participation for flexibility in enabling higher renewable penetration and lower emissions.

Abstract

In the recent years, the interest in electric direct current (DC) technologies (such as converters, batteries, electric vehicles, etc.) is increasing due to its potential on energy efficiency and sustainability. However, the vast majority of electric systems and networks are based on alternating current (AC), as they also have certain advantages regarding cost-effective transport and robustness. In this paper, an AC/DC optimal power flow method for hybrid microgrids and several key performance indicators (KPIs) for its techno-economic assessment are presented. The combination of both calculations allows users to clearly determine the viability of their hybrid microgrids. AC/DC networks have been modelled considering their most common elements. For the power flow method, a polynomial optimisation is formulated considering four different objective functions: the minimisation of energy losses, voltage deviation and operational costs, and also the maximisation of the microgrid generation. The power flow method and the techno-economic analysis have been implemented in Python and validated in the Centro de Desarrollo de Energías Renovables (CEDER) demonstrator for TIGON. The results show that the calculated power flow variables and the ones measured at CEDER are practically the same. In addition, the KPIs have been obtained and compared for four operating scenarios: baseline, no battery, battery flexibility and virtual battery (VB) flexibility. The last one result in the most profitable option.

Figures (3)

• Figure 1: CEDER facilities (left) and TIGON demostrator (right).
• Figure 2: TIGON layout at CEDER.
• Figure 3: $\pi$ model of lines.