# Estimation Method of Short-Circuit Current Contribution of Inverter-Based Resources for Symmetrical Faults

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## Abstract

**:**

## 1. Introduction

- The change in the fault current level, whose value is applied to adjust the coordination time interval (CTI) between adjacent overcurrent protection devices (OCPDs);
- The coordination loss, highlighting the blind protection, sympathetic tripping and fuse protection philosophy (fuse-blow and fuse-saving);
- The change in the load current, whose value is used to adjust the sensitivity of the OCPDs.

## 2. Estimating the Short-Circuit Current Contribution for Symmetrical Faults

#### 2.1. Distribution Feeder without Lateral Branches

_{k}, IBR

_{(k+1)}, …, IBR

_{m}, from Figure 1), considering the same 3LG fault discussed previously, the currents through the OCPDs are the same and given by Equation (2).

_{j}, IBR

_{(j+1)}, …, IBR

_{w}, from Figure 1), taking into consideration the previous fault condition, the currents through OCPD1 and OCPD2 are the same as presented in Equation (3).

_{i}, IBR

_{(i+1)}, …, IBR

_{n}, from Figure 1), the currents through OCPD1 and OCPD2 are different and given by Equations (4) and (5), respectively.

#### 2.2. Distribution Feeder with Lateral Branches

#### 2.2.1. Fault without IBRs

#### 2.2.2. Fault with IBRs

#### 2.2.3. Feeder Dominated by IBRs

#### 2.3. A General Equation

- The substation;
- The IBRs located upstream seen from the perspective of the OCPD;
- The IBRs located downstream seen from the perspective of the OCPD.

## 3. Sensitivity Analysis of the General Equations

#### 3.1. OCPD Installed on Main Fault Trunk

#### 3.1.1. Upstream IBRs

#### 3.1.2. Downstream IBRs

#### 3.2. OCPD Installed on a Lateral of the Main Fault Trunk

#### 3.3. Intermediate Remarks

- The OCPD may be affected by the minimum fault at the end of the lateral;
- The reverse fault current through the OCPD may be greater than in the case without IBRs;
- The load current can be greater than in the case without IBRs.

## 4. Protection Coordination in Distribution Networks Dominated by IBRs

#### 4.1. Classical Protection Coordination

#### 4.2. Changing the Slope of the Characteristic Curves

#### 4.3. Adjustment of TMS

## 5. Case Study

#### 5.1. Overcurrent Protection for IEEE 34-Node Radial Test Feeder

#### 5.1.1. Placing the OCPDs

#### 5.1.2. Fuse Settings

#### 5.1.3. Relay Settings

#### 5.2. Estimation of the Short-Circuit Current Contribution

#### 5.2.1. IBRs on the Main Fault Trunk

- IBR upstream R1 (right before)—Case 1;
- IBR between R1 and R2 (righ after R1)—Case 2;
- IBR between R1 and R2 (right before R2)—Case 3;
- IBR downstream R2 (right after)—Case 4.

#### 5.2.2. IBRs on Lateral

- IBR right after fuse FS8—Case Begin;
- IBR at node 848—Case End.

#### 5.3. Impacts on the Actual Phase Protection Coordination Scheme

#### 5.4. Changing the Actual Phase Protection Scheme

#### 5.5. Assertiveness of the New Phase Protection Scheme

## 6. Conclusions

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

3LG | Three-phase line-to-ground |

ACSR | Aluminium-conductor steel-reinforced |

CTI | Coordination time interval |

CSI | Current source inverter |

DERs | Distributed energy resources |

DN | Distribution network |

DNO | Distribution network operator |

EI | Extreme inverse |

FS | Fuse |

IBRs | Inverter-based resources |

MFT | Main fault trunk |

OCPDs | Overcurrent protection devices |

PCC | Point of common coupling |

PL | Penetration level |

PV | Photovoltaic |

SCC | Short-circuit current |

TMS | Time multiplies settings |

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**Figure 1.**Single-line diagram of a radial distribution feeder, with two OCPDs, dominated by IBRs, and a three-phase line-to-ground fault at point F.

**Figure 5.**Hypothetical extreme situations for fault currents through OCPDs in a high penetration scenario of IBRs.

**Figure 7.**Strategy to restore the protection coordination between two OCPDs in a distribution feeder dominated by IBRs.

**Figure 10.**Phase fault protection coordination for R1 (in black), R2 (in red) and fuses 6 K, 15 K and 25 K. The vertical lines represent fault currents: downwards triangle is a 3LG fault, X is a phase-to-phase fault and circle is the maximum fault through the highest fuse for R2. The SCC damage curves for ACSR 1/0 and #2 6/1 bare conductors are also represented.

**Figure 11.**Earth fault protection coordination for R1 (in black), R2 (in red) and fuses 6 K, 15 K and 25 K. The vertical lines represent fault currents: upwards triangle is a line-to-earth fault. The SCC damage curves for ACSR 1/0 and #2 6/1 bare conductors are also represented.

**Figure 12.**Modified phase fault protection coordination for R1 (in black), R2 (in red) and fuse 25 K, considering a 100% PL of IBRs and different SCC contribution capacities on IBR’s base rating. The continuous curves represent the protection coordination without IBRs.

**Table 1.**Maximum load currents, minimum line-to-ground faults and fuse link to protect laterals on the IEEE 34-node test feeder.

Max. Load Current (A) | Min. Line-to-Ground Fault (A) | Fuse Link | |
---|---|---|---|

FS1 | 1.22 | 298.00 | 6 K |

FS2 | 13.02 | 135.30 | 25 K |

FS3 | 10.62 | 135.30 | 15 K |

FS4 | 3.10 | 190.40 | 6 K |

FS5 | 0.31 | 148.00 | 6 K |

FS6 | 11.70 | 94.00 | 20 K |

FS7 | 0.14 | 139.40 | 6 K |

FS8 | 16.30 | 133.60 | 25 K |

FS9 | 2.09 | 131.40 | 6 K |

Max. Load Current (A) | Max. Three Phase Fault (A) | Max. Double Phase Fault (A) | Max. Single Phase Fault (A) | Min. Three Phase Fault (A) | Min. Double Phase Fault (A) | Min. Single Phase Fault (A) | Neutral Current (A) | |
---|---|---|---|---|---|---|---|---|

R1 | 51.56 | 627.3 | 543.3 | 655.2 | 439.9 | 471.7 | 135.3 | 11.13 |

R2 | 37.77 | 292.8 | 253.8 | 235.4 | 221.0 | 216.3 | 131.4 | 4.55 |

Phase Protection | Earth Protection | ||
---|---|---|---|

R1 | Pickup (A) | 90 | 40 |

Curve – IEC 60255 | EI | EI | |

TMS | 0.09 | 0.34 | |

R2 | Pickup (A) | 75 | 30 |

Curve – IEC 60255 | EI | EI | |

TMS | 0.07 | 0.38 |

**Table 4.**CTI between relays and fuses FS2 and FS8 for maximum and minimum fault types on the IEEE 34-node test feeder.

A | B | Fault (A)3LG | A TrippingTime (ms) | B TrippingTime (ms) | CTI (ms)(A–B) | Fault (A)2L | A TrippingTime (ms) | B TrippingTime (ms) | CTI (ms)(A–B) | ||

R1 | R2 | Max. | 292.8 | 751.2 | 393.2 | 358.0 | Max. | 253.8 | 1035.6 | 535.8 | 499.8 |

Min. | 221.0 | 1431.5 | 728.9 | 702.6 | Min. | 216.3 | 1507.5 | 765.3 | 742.2 | ||

R2 | FS8 | Max. | 203.4 | 881.2 | 433.7 | 447.5 | Max. | 175.0 | 1260.0 | 588.1 | 671.9 |

Min. | 159.3 | 1594.8 | 714.0 | 880.8 | Min. | 152.8 | 1777.4 | 779.7 | 997.6 | ||

A | B | Fault (A)LG (start) | A TrippingTime (ms) | B TrippingTime (ms) | CTI (ms)(A–B) | Fault (A)LG (end) | A TrippingTime (ms) | B TrippingTime (ms) | CTI (ms)(A–B) | ||

R1 | R2 | Max. | 235.4 | 808.7 | 501.9 | 306.8 | Max. | 150.7 | 2061.5 | 1254.4 | 807.1 |

Min. | 194.0 | 1207.7 | 744.8 | 462.9 | Min. | 131.4 | 2778.0 | 1671.8 | 1106.2 | ||

FS2 | Max. | 254.9 | 686.7 | 278.3 | 408.4 | Max. | 157.3 | 1880.5 | 731.6 | 1148.8 | |

Min. | 207.9 | 1045.6 | 416.3 | 629.3 | Min. | 135.3 | 2605.0 | 1020.1 | 1584.9 | ||

R2 | FS8 | Max. | 158.3 | 1132.5 | 722.8 | 409.7 | Max. | 154.0 | 1199.2 | 765.7 | 433.4 |

Min. | 137.0 | 1531.1 | 992.0 | 539.1 | Min. | 133.6 | 1614.3 | 1048.1 | 566.1 |

**Table 5.**Currents Through R1 and R2 for a 3LG Fault at Node 840 on the IEEE 34-Node Test Feeder and IBR Located on the MFT for Different Penetration Levels (PL) and Fault Resistances (${Z}_{f}$).

${\mathit{Z}}_{\mathit{f}}=0\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | ${\mathit{Z}}_{\mathit{f}}=20\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | Error (%) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|

PL | Case | Method | Simulink | Method | Simulink | Method/ | ||||||

Current | Current | Current | Current | Simulink | ||||||||

(A) | % | (A) | % | (A) | % | (A) | % | $0\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | $20\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | |||

0% | R1 | 199.91 | - | 197.66 | - | 164.41 | - | 164.42 | - | 1.1% | 0.0% | |

R2 | 199.91 | - | 195.20 | - | 164.41 | - | 161.08 | - | 2.4% | 2.1% | ||

25% | 1 | R1 | 200.36 | 0.2% | 199.67 | 1.0% | 164.79 | 0.2% | 166.38 | 1.2% | 0.3% | −1.0% |

R2 | 200.36 | 0.2% | 196.64 | 0.7% | 164.79 | 0.2% | 162.46 | 0.9% | 1.9% | 1.4% | ||

2 | R1 | 191.53 | −4.2% | 189.23 | −4.3% | 154.71 | −5.9% | 155.38 | −5.5% | 1.2% | −0.4% | |

R2 | 200.36 | 0.2% | 196.64 | 0.7% | 164.79 | 0.2% | 162.46 | 0.9% | 1.9% | 1.4% | ||

3 | R1 | 195.86 | −2.0% | 194.16 | −1.8% | 158.27 | −3.7% | 159.23 | −3.2% | 0.9% | −0.6% | |

R2 | 204.83 | 2.5% | 202.37 | 3.7% | 168.46 | 2.5% | 167.10 | 3.7% | 1.2% | 0.8% | ||

4 | R1 | 195.86 | −2.0% | 194.16 | −1.8% | 158.27 | −3.7% | 159.23 | −3.2% | 0.9% | −0.6% | |

R2 | 195.86 | −2.0% | 191.09 | −2.1% | 158.27 | −3.7% | 155.25 | −3.6% | 2.5% | 1.9% | ||

50% | 1 | R1 | 200.87 | 0.5% | 200.77 | 1.6% | 165.21 | 0.5% | 167.22 | 1.7% | 0.0% | −1.2% |

R2 | 200.87 | 0.5% | 197.73 | 1.3% | 165.21 | 0.5% | 163.28 | 1.4% | 1.6% | 1.2% | ||

2 | R1 | 183.30 | −8.3% | 180.13 | −8.9% | 145.14 | −11.7% | 145.51 | −11.5% | 1.8% | −0.3% | |

R2 | 200.87 | 0.5% | 197.73 | 1.3% | 165.21 | 0.5% | 163.28 | 1.4% | 1.6% | 1.2% | ||

3 | R1 | 191.84 | −4.0% | 189.85 | −4.0% | 152.15 | −7.5% | 152.97 | −7.0% | 1.0% | −0.5% | |

R2 | 209.94 | 5.0% | 209.11 | 7.1% | 172.66 | 5.0% | 172.53 | 7.1% | 0.4% | 0.1% | ||

4 | R1 | 191.84 | −4.0% | 189.85 | −4.0% | 152.15 | −7.5% | 152.97 | −7.0% | 1.0% | −0.5% | |

R2 | 191.84 | −4.0% | 186.71 | −4.3% | 152.15 | −7.5% | 148.90 | −7.6% | 2.7% | 2.2% | ||

75% | 1 | R1 | 201.44 | 0.8% | 201.82 | 2.1% | 165.67 | 0.8% | 168.02 | 2.2% | −0.2% | −1.4% |

R2 | 201.44 | 0.8% | 198.76 | 1.8% | 165.67 | 0.8% | 164.06 | 1.9% | 1.3% | 1.0% | ||

2 | R1 | 175.24 | −12.3% | 171.24 | −13.4% | 135.72 | −17.5% | 135.88 | −17.4% | 2.3% | −0.1% | |

R2 | 201.44 | 0.8% | 198.76 | 1.8% | 165.67 | 0.8% | 164.06 | 1.9% | 1.3% | 1.0% | ||

3 | R1 | 187.83 | −6.0% | 185.59 | −6.1% | 146.04 | −11.2% | 146.70 | −10.8% | 1.2% | −0.4% | |

R2 | 215.24 | 7.7% | 215.70 | 10.5% | 177.02 | 7.7% | 177.88 | 10.4% | −0.2% | −0.5% | ||

4 | R1 | 187.83 | −6.0% | 185.59 | −6.1% | 146.04 | −11.2% | 146.70 | −10.8% | 1.2% | −0.4% | |

R2 | 187.83 | −6.0% | 182.40 | −6.6% | 146.04 | −11.2% | 142.56 | −11.5% | 3.0% | 2.4% | ||

100% | 1 | R1 | 202.06 | 1.1% | 202.82 | 2.6% | 166.19 | 1.1% | 168.77 | 2.6% | −0.4% | −1.5% |

R2 | 202.06 | 1.1% | 199.75 | 2.3% | 166.19 | 1.1% | 164.79 | 2.3% | 1.2% | 0.8% | ||

2 | R1 | 167.38 | −16.3% | 162.62 | −17.7% | 126.50 | −23.1% | 126.52 | −23.0% | 2.9% | 0.0% | |

R2 | 202.06 | 1.1% | 199.75 | 2.3% | 166.19 | 1.1% | 164.79 | 2.3% | 1.2% | 0.8% | ||

3 | R1 | 183.85 | −8.0% | 181.40 | −8.2% | 139.96 | −14.9% | 140.43 | −14.6% | 1.4% | −0.3% | |

R2 | 220.70 | 10.4% | 222.15 | 13.8% | 181.52 | 10.4% | 183.14 | 13.7% | −0.7% | −0.9% | ||

4 | R1 | 183.85 | −8.0% | 181.40 | −8.2% | 139.96 | −14.9% | 140.43 | −14.6% | 1.4% | −0.3% | |

R2 | 183.85 | −8.0% | 178.15 | −8.7% | 139.96 | −14.9% | 136.22 | −15.4% | 3.2% | 2.7% |

**Table 6.**Currents Through R1 and R2 for a 3LG Fault at Node 840 on IEEE 34-Node Test Feeder and IBR Located on the Lateral 7 for Different Penetration Levels (PL) and Fault Resistances (${Z}_{f}$).

${\mathit{Z}}_{\mathit{f}}=0\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | ${\mathit{Z}}_{\mathit{f}}=20\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | Error (%) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|

PL | Case | Method | Simulink | Method | Simulink | Method/ | ||||||

Current | Current | Current | Current | Simulink | ||||||||

(A) | % | (A) | % | (A) | % | (A) | % | $0\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | $20\phantom{\rule{4pt}{0ex}}\mathbf{\Omega}$ | |||

0% | R1 | 199.91 | - | 198.51 | - | 164.41 | - | 165.49 | - | 0.7% | −0.6% | |

R2 | 199.91 | - | 195.50 | - | 164.41 | - | 161.59 | - | 2.3% | 1.7% | ||

FS8 | 0.00 | - | 0.41 | - | 0.00 | - | 3.55 | - | −100.0% | −100.0% | ||

25% | Begin | R1 | 199.60 | −0.2% | 198.51 | 0.0% | 161.35 | −1.9% | 163.22 | −1.4% | 0.5% | −1.1% |

R2 | 199.60 | −0.2% | 195.50 | 0.0% | 161.35 | −1.9% | 159.27 | −1.4% | 2.1% | 1.3% | ||

FS8 | 12.31 | - | 0.41 | 0.0% | 12.31 | - | 9.78 | 175.2% | 2938.0% | 25.9% | ||

End | R1 | 199.60 | −0.2% | 198.51 | 0.0% | 161.35 | −1.9% | 163.22 | −1.4% | 0.5% | −1.1% | |

R2 | 199.60 | −0.2% | 195.50 | 0.0% | 161.35 | −1.9% | 159.27 | −1.4% | 2.1% | 1.3% | ||

FS8 | 12.31 | - | 0.41 | 0.0% | 12.31 | - | 9.77 | 175.0% | 2938.0% | 25.9% | ||

50% | Begin | R1 | 199.30 | −0.3% | 198.51 | 0.0% | 158.28 | −3.7% | 160.88 | −2.8% | 0.4% | −1.6% |

R2 | 199.30 | −0.3% | 195.50 | 0.0% | 158.28 | −3.7% | 156.87 | −2.9% | 1.9% | 0.9% | ||

FS8 | 24.61 | - | 0.41 | 0.0% | 24.61 | - | 21.72 | 511.3% | 5975.9% | 13.3% | ||

End | R1 | 199.30 | −0.3% | 198.51 | 0.0% | 158.28 | −3.7% | 160.86 | −2.8% | 0.4% | −1.6% | |

R2 | 199.30 | −0.3% | 195.50 | 0.0% | 158.28 | −3.7% | 156.86 | −2.9% | 1.9% | 0.9% | ||

FS8 | 24.61 | - | 0.41 | 0.0% | 24.61 | - | 21.71 | 510.9% | 5975.9% | 13.4% | ||

75% | Begin | R1 | 199.00 | −0.5% | 198.51 | 0.0% | 155.22 | −5.6% | 158.46 | −4.2% | 0.2% | −2.0% |

R2 | 199.00 | −0.5% | 195.50 | 0.0% | 155.22 | −5.6% | 154.41 | −4.4% | 1.8% | 0.5% | ||

FS8 | 36.92 | - | 0.41 | 0.0% | 36.92 | - | 33.77 | 850.5% | 9013.9% | 9.3% | ||

End | R1 | 199.00 | −0.5% | 198.51 | 0.0% | 155.22 | −5.6% | 158.42 | −4.3% | 0.2% | −2.0% | |

R2 | 199.00 | −0.5% | 195.50 | 0.0% | 155.22 | −5.6% | 154.36 | −4.5% | 1.8% | 0.6% | ||

FS8 | 36.92 | - | 0.41 | 0.0% | 36.92 | - | 33.75 | 849.9% | 9013.9% | 9.4% | ||

100% | Begin | R1 | 198.69 | −0.6% | 198.51 | 0.0% | 152.15 | −7.5% | 155.98 | −5.7% | 0.1% | -2.5% |

R2 | 198.69 | −0.6% | 195.50 | 0.0% | 152.15 | −7.5% | 151.87 | −6.0% | 1.6% | 0.2% | ||

FS8 | 49.22 | - | 0.41 | 0.0% | 49.22 | - | 45.85 | 1190.4% | 12,051.8% | 7.4% | ||

End | R1 | 198.69 | −0.6% | 198.51 | 0.0% | 152.15 | −7.5% | 155.90 | −5.8% | 0.1% | −2.4% | |

R2 | 198.69 | −0.6% | 195.50 | 0.0% | 152.15 | −7.5% | 151.79 | −6.1% | 1.6% | 0.2% | ||

FS8 | 49.22 | - | 0.41 | 0.0% | 49.22 | - | 45.82 | 1189.6% | 12,051.8% | 7.4% |

**Table 7.**Tripping Times for R1 and R2 for a Fault at Node 828 of the IEEE 34-Node Test Feeder with 100% of Penetration Level of IBRs.

IBR SCC | Case | R1 (A) | R2 (A) | R1 (ms) | R2 (ms) | Δt (ms) |
---|---|---|---|---|---|---|

0 pu | - | 303.91 | 303.91 | 692 | 363 | 329 |

1.2 pu | 1 | 307.18 | 307.18 | 676 | 355 | 321 |

2 | 277.86 | 307.18 | 844 | 355 | 489 | |

3 | 300.63 | 332.07 | 709 | 301 | 408 | |

4 | 300.63 | 300.63 | 709 | 372 | 337 | |

2.0 pu | 1 | 310.91 | 310.91 | 659 | 346 | 313 |

2 | 261.33 | 310.91 | 969 | 346 | 623 | |

3 | 298.45 | 352.93 | 720 | 265 | 455 | |

4 | 298.45 | 298.45 | 720 | 377 | 343 |

**Table 8.**Tripping Times for R1, R2 and FS8 for a Fault at Node 834 of the IEEE 34-Node Test Feeder with 100% Penetration Level of IBRs.

IBR SCC | Case | R1 (A) | R2 (A) | FS8 (A) | R1 Trip (ms) | R2 Trip (ms) | FS8 Trip (ms) | Δt (R1-R2) (ms) | Δt (R2-FS8) (ms) |
---|---|---|---|---|---|---|---|---|---|

0 pu | - | 199.68 | 199.68 | 199.68 | 1836 | 920 | 448 | 916 | 472 |

1.2 pu | 1 | 201.83 | 201.83 | 201.83 | 1787 | 897 | 439 | 890 | 458 |

2 | 167.14 | 201.83 | 201.83 | 2940 | 897 | 439 | 2043 | 458 | |

3 | 183.59 | 220.45 | 220.45 | 2278 | 733 | 368 | 1545 | 365 | |

4 | 183.59 | 183.59 | 220.45 | 2278 | 1122 | 368 | 1156 | 754 | |

5 | 198.41 | 198.41 | 236.29 | 1865 | 934 | 321 | 932 | 613 | |

6 | 198.41 | 198.41 | 198.41 | 1865 | 934 | 455 | 932 | 479 | |

2.0 pu | 1 | 203.77 | 203.77 | 203.77 | 1745 | 878 | 432 | 867 | 446 |

2 | 147.37 | 203.77 | 203.77 | 4283 | 878 | 432 | 3405 | 446 | |

3 | 173.10 | 235.75 | 235.75 | 2667 | 631 | 322 | 2037 | 309 | |

4 | 173.10 | 173.10 | 235.75 | 2667 | 1294 | 322 | 1373 | 972 | |

5 | 197.56 | 197.56 | 262.71 | 1885 | 943 | 263 | 942 | 680 | |

6 | 197.57 | 197.57 | 197.57 | 1885 | 943 | 459 | 942 | 484 |

IBR with SCC of 1.2 pu | IBR with SCC of 2.0 pu | ||
---|---|---|---|

R1 | Pickup (A) | 90 | 90 |

Curve-IEC 60255 | EI | EI | |

TMS | 0.10 | 0.11 | |

R2 | Pickup (A) | 75 | 75 |

Curve-IEC 60255 | EI | EI | |

TMS | 0.08 | 0.09 |

**Table 10.**Tripping times and CTI Between R1, R2 and FS8 for the New Adjustments for Phase Protection of the IEEE 34-Node Test Feeder with 100% PL of IBRs.

IBR SCC | A | B | Fault (A) 3LG | A Trip (ms) | B Trip (ms) | A-B (ms) |
---|---|---|---|---|---|---|

1.2 pu | R1 | R2 | 307.18 | 751 | 406 | 346 |

R2 | FS8 | 220.45 | 838 | 368 | 470 | |

2.0 pu | R1 | R2 | 310.91 | 805 | 445 | 360 |

R2 | FS8 | 235.75 | 811 | 322 | 489 |

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## Share and Cite

**MDPI and ACS Style**

Vargas, M.C.; Batista, O.E.; Yang, Y.
Estimation Method of Short-Circuit Current Contribution of Inverter-Based Resources for Symmetrical Faults. *Energies* **2023**, *16*, 3130.
https://doi.org/10.3390/en16073130

**AMA Style**

Vargas MC, Batista OE, Yang Y.
Estimation Method of Short-Circuit Current Contribution of Inverter-Based Resources for Symmetrical Faults. *Energies*. 2023; 16(7):3130.
https://doi.org/10.3390/en16073130

**Chicago/Turabian Style**

Vargas, Murillo Cobe, Oureste Elias Batista, and Yongheng Yang.
2023. "Estimation Method of Short-Circuit Current Contribution of Inverter-Based Resources for Symmetrical Faults" *Energies* 16, no. 7: 3130.
https://doi.org/10.3390/en16073130