# A Coordinated Voltage Control for Overvoltage Mitigation in LV Distribution Grids

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Challenges of DG Integration

#### 2.1. Voltage Rise

#### 2.2. DG Active and Reactive Power Regulation

**R**and

**X**are the real and imaginary part of the impedance matrix

**Z**.

#### 2.3. Energy Storage System Management

## 3. Coordinated Voltage Control

- ${\mathbf{R}}^{ESS}=Re{\left\{{\mathbf{Z}}_{h}\right\}}_{h\in ESS}$ is the real part of the submatrix ${\mathbf{Z}}_{h}$ obtained when considering only the rows and columns of
**Z**associated to the nodes h where the ESSs are connected. - ${\mathbf{R}}^{DG}=Re{\left\{{\mathbf{Z}}_{h}\right\}}_{h\in DG}$ is the real part of the submatrix ${\mathbf{Z}}_{h}$ obtained when considering only the rows and columns of
**Z**associated to the nodes h where DGs are connected. - ${\mathbf{X}}^{DG}=Im{\left\{{\mathbf{Z}}_{h}\right\}}_{h\in DG}$ is the imaginary part of the submatrix ${\mathbf{Z}}_{h}$ obtained when considering only the rows and columns of
**Z**associated to the nodes h where DGs are connected. - $\Delta {\mathbf{p}}_{+}^{ESS}$, $\Delta {\mathbf{p}}_{+}^{DG}$ and $\Delta {\mathbf{q}}_{+}^{DG}$ are the subvectors of $\Delta {\mathbf{p}}^{ESS}$, $\Delta {\mathbf{p}}^{DG}$ and $\Delta {\mathbf{q}}^{DG}$ associated to the only nodes where ESSs and DG are present, respectively.

#### 3.1. Energy Storage Active Power Control

- (1)
- dual-ascent steps on the dual variables ${\mathbf{\lambda}}_{min}^{p},{\mathbf{\lambda}}_{max}^{p}$;
- (2)
- dual-ascent steps on the dual variables ${\mathbf{\chi}}_{min},{\mathbf{\chi}}_{max}$;
- (3)
- unconstrained minimization on the primal variable $\Delta {\mathbf{p}}_{+}^{ESS}$.

#### 3.2. DG Active Power Control

#### 3.3. DG Reactive Power Control

#### 3.4. DG and ESS Coordination

#### 3.5. Addition of Virtual Nodes

## 4. Simulation Setup

#### 4.1. Distribution Grid

#### 4.2. Load Data

#### 4.3. PV Data and Model

## 5. Simulation Results

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 6.**Generated PV profiles for clear sky and cloudy weather conditions. (

**a**) Photovoltaic (PV) profiles under clear sky conditions. (

**b**) PV profiles under cloudy conditions.

**Figure 7.**Voltage profile of the grid for different control strategies under clear sky conditions. (

**a**) No control (

**b**) Only DG control (

**c**) Both DG and ESSs control.

**Figure 8.**Distributed control applied only to DG. (

**a**) Active power generated by PVs (

**b**) Reactive power generated by PVs.

**Figure 9.**Distributed control applied to both Distributed Generation (DG) and Energy Storage Systems (ESSs). (

**a**) Active power generated by PVs (

**b**) Percentage level of PV energy production.

**Figure 10.**ESS power and DG energy production with prioritized use of the ESS over the DG. (

**a**) Reactive Power generated by PVs. (

**b**) Active power injected by ESSs.

**Figure 11.**ESS power and DG reactive power with prioritized use of the DG over the ESS. (

**a**) Reactive power generated by PVs. (

**b**) Active power injected by ESS.

**Figure 12.**Results for the designed control strategy under cloudy sky conditions. (

**a**) Voltage profile. (

**b**) Active power injected by ESS.

**Figure 13.**Voltage profile without virtual nodes and with virtual nodes. (

**a**) Without virtual nodes (

**b**) With virtual nodes.

**Figure 14.**DG and ESS power injection in scenario without virtual nodes. (

**a**) DG reactive power (

**b**) ESS active power.

**Figure 15.**DG and ESS power injection in scenario with virtual nodes. (

**a**) DG reactive power (

**b**) ESS active power.

ID | Start Node | End Node | Per Unit Resistance | Per Unit Reactance | Node ID | No. Customers |
---|---|---|---|---|---|---|

01 | 1 | 2 | 0.0004 | 0.003172 | 2 | 0 |

02 | 2 | 3 | 0.00108675 | 0.0004095 | 3 | 2 |

03 | 3 | 4 | 0.000426938 | 0.000160875 | 4 | 1 |

04 | 4 | 5 | 0.00087975 | 0.0003315 | 5 | 1 |

05 | 5 | 6 | 0.0009315 | 0.000351 | 6 | 1 |

06 | 3 | 7 | 0.001358438 | 0.000511875 | 7 | 2 |

07 | 7 | 8 | 3.88125E-05 | 0.000014625 | 8 | 6 |

08 | 7 | 9 | 0.000685688 | 0.000258375 | 9 | 1 |

09 | 7 | 10 | 0.00098325 | 0.0003705 | 10 | 3 |

10 | 7 | 11 | 0.000711563 | 0.000268125 | 11 | 3 |

11 | 10 | 12 | 0.00098325 | 0.0003705 | 12 | 2 |

12 | 10 | 13 | 0.0007245 | 0.000273 | 13 | 4 |

13 | 13 | 14 | 0.000414 | 0.000156 | 14 | 2 |

14 | 11 | 15 | 0.000905625 | 0.00034125 | 15 | 1 |

15 | 15 | 16 | 0.000802125 | 0.00030225 | 16 | 2 |

16 | 15 | 17 | 0.000336375 | 0.00012675 | 17 | 3 |

17 | 17 | 18 | 0.000659813 | 0.000248625 | 18 | 1 |

18 | 18 | 19 | 0.000530438 | 0.000199875 | 19 | 2 |

19 | 19 | 20 | 0.000815063 | 0.000307125 | 20 | 5 |

20 | 20 | 21 | 0.000336375 | 0.00012675 | 21 | 2 |

21 | 21 | 22 | 0.00025875 | 0.0000975 | 22 | 4 |

22 | 22 | 23 | 0.000452813 | 0.000170625 | 23 | 4 |

Case | Reactive Power Injection PVs (kVAR) | Active Power Curtailment PVs (kW) | Active Power Injections ESSs (kW) |
---|---|---|---|

No ESSs | −4.3 | −2.1 | 0.0 |

ESSs priority | −0.3 | 0.0 | −5.5 |

PVs priority | −4.4 | 0.0 | −2.0 |

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## Share and Cite

**MDPI and ACS Style**

De Din, E.; Pau, M.; Ponci, F.; Monti, A. A Coordinated Voltage Control for Overvoltage Mitigation in LV Distribution Grids. *Energies* **2020**, *13*, 2007.
https://doi.org/10.3390/en13082007

**AMA Style**

De Din E, Pau M, Ponci F, Monti A. A Coordinated Voltage Control for Overvoltage Mitigation in LV Distribution Grids. *Energies*. 2020; 13(8):2007.
https://doi.org/10.3390/en13082007

**Chicago/Turabian Style**

De Din, Edoardo, Marco Pau, Ferdinanda Ponci, and Antonello Monti. 2020. "A Coordinated Voltage Control for Overvoltage Mitigation in LV Distribution Grids" *Energies* 13, no. 8: 2007.
https://doi.org/10.3390/en13082007