# Enhancing Virtual Inertia Control in Microgrids: A Novel Frequency Response Model Based on Storage Systems

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## Abstract

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## 1. Introduction

## 2. Fundamental Concept and Structure of Virtual Inertia Control

## 3. Frequency Analysis for Virtual Inertia Control and Virtual Dropping

## 4. Case Study Modeling

## 5. Simulation Results and Discussion

- Under operating conditions, the contributions of wind generation, solar generation, and electrical loads are treated as uncertainties or disturbances of the system.
- The dynamic effects of generation–load interaction are smoothed out, while primary, secondary, and virtual inertia control blocks are implemented. This is developed without compromising the results according to the literature collected in each corresponding block.
- The virtual inertia control utilizing Energy Storage Systems (ESS) is tasked with providing power that includes the necessary inertia within a timeframe of 1 to 5 s, coinciding with the onset of disturbances caused by the integration of renewable generation into the electrical system.
- The primary control unit’s governor is tasked with restoring the frequency system to a new stable state within the first 10 to 40 s as established by regulations.
- The secondary frequency control’s objective is to return the system frequency to its nominal value in a set range of up to 30 min.

#### 5.1. Dynamic Simulation of Frequency Response without RES Penetration

#### 5.2. Dynamic Simulation of Frequency Response with RES Penetration

## 6. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 7.**Dynamic response when the inertia constant H drops to 50% without virtual inertia control.

**Figure 9.**Frequency response wind and solar penetration (

**a**) virtual inertia control and (

**b**) virtual dropping.

**Figure 10.**System response with wind and solar penetration through variation of electrical demand in steps.

**Figure 11.**System response with wind and solar penetration through variation of electrical demand in steps (section).

Condition | % Reserve under the Effective Power of the Generators |
---|---|

Interconnected Ecuador | 2.0 |

Isolated Ecuador | 3.0 |

DEMAND | Above Reserve Required for SFR (MW) | Below Reserve Required for SFR (MW) |
---|---|---|

Minimum | 187.50 | 105 |

Half | 187.50 | 105 |

Maximum | 187.50 | 105 |

Description | Symbol | Parameter Value |
---|---|---|

Thermal Power Station (Governor) | ${T}_{g}$ | 0.07 |

Thermal Power Station (Turbine) | ${T}_{t}$ | 0.37 |

Wind Generation Unit | ${T}_{WT}$ | 1.4 |

Solar Generation Unit | ${T}_{PV}$ | 1.9 |

Primary control loop—droop | $1/R$ | 1/2.6 |

Secondary control loop—bias | $\beta $ | 0.98 |

Area control error | ${K}_{S}$ | 0.1 |

Proporcional compoment VIC | ${R}_{VI}$ | 2.7 |

Virtual damping coefficient | ${D}_{VI}$ | 0.016 |

Inertia constant | H | 0.083 |

Virtual inertia characteristics | ${K}_{VI}$ | −0.6 |

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**MDPI and ACS Style**

Criollo, A.; Minchala-Avila, L.I.; Benavides, D.; Arévalo, P.; Tostado-Véliz, M.; Sánchez-Lozano, D.; Jurado, F.
Enhancing Virtual Inertia Control in Microgrids: A Novel Frequency Response Model Based on Storage Systems. *Batteries* **2024**, *10*, 18.
https://doi.org/10.3390/batteries10010018

**AMA Style**

Criollo A, Minchala-Avila LI, Benavides D, Arévalo P, Tostado-Véliz M, Sánchez-Lozano D, Jurado F.
Enhancing Virtual Inertia Control in Microgrids: A Novel Frequency Response Model Based on Storage Systems. *Batteries*. 2024; 10(1):18.
https://doi.org/10.3390/batteries10010018

**Chicago/Turabian Style**

Criollo, Adrián, Luis I. Minchala-Avila, Dario Benavides, Paul Arévalo, Marcos Tostado-Véliz, Daniel Sánchez-Lozano, and Francisco Jurado.
2024. "Enhancing Virtual Inertia Control in Microgrids: A Novel Frequency Response Model Based on Storage Systems" *Batteries* 10, no. 1: 18.
https://doi.org/10.3390/batteries10010018