# System Integrity Protection Scheme (SIPS) Development and an Optimal Bus-Splitting Scheme Supported by Phasor Measurement Units (PMUs)

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## Abstract

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## 1. Introduction

- Congestion in parts of the power transmission network due to the electricity market conditions in its control [10],
- High shares of electricity production from renewable sources, which is characterized by variable generation and difficult scheduling [11],
- Changes in the nature and structure of electricity consumption (electrical vehicles, etc.), and
- Coordination of local relay protection systems in different parts of the EPS [12].

## 2. System Integrity Protection Scheme (SIPS)

## 3. System Integrity Protection Scheme Development Method

#### 3.1. Disturbance

#### 3.2. Scenario Definition for Power System Analysis

#### 3.3. Scenario Analysis

#### 3.4. SIPS Selection

#### 3.5. SIPS Initiation Conditions

#### 3.6. Power Network Security Assessment with and without SIPS Implementation

## 4. Mathematical Description of the Optimal Bus-Splitting Problem

- line resistance R
_{L}is negligible in relation to line reactance X_{L},$${R}_{L}\ll {X}_{L};$$ - per unit voltage |V
_{N}| is the same for all nodes,$$\left|{V}_{N}\right|=1p.u.;$$ - voltage angles difference δ
_{i}− δ_{j}of the adjacent nodes is small, which derives:$$\mathrm{sin}\left({\delta}_{i}-{\delta}_{j}\right)\approx \left({\delta}_{i}-{\delta}_{j}\right);\mathrm{cos}\left({\delta}_{i}-{\delta}_{j}\right)\approx 1.$$

_{Pe}in order to replace the inequality of the DC network model with respect to the actual state of the power system. The adjustment factor is calculated in real time using synchronized phasor measurements. The model features exceptional performance speeds that enable its use in SIPS and, consequently, preserves the security of the power system in its entirety.

- e—element tag,
- i, j—node tag,
- P
_{e}—active power flow for element e, - δ
_{i}, δ_{j}—voltage phase angle for node i and j, - X
_{e}—element e reactance, - VARE
_{e}—decision variable which represents element e in the closed or open state, defined as binary value 0 for open or 1 for closed state, - E—number of elements,
- N—number of nodes, and
- δ
_{REF}—reference voltage phase angle.

- M
_{e}—linearization factor for element e, defined by Expression (8).

- δ
_{MAX}—maximum voltage phase angle, and - δ
_{MIN}—minimum voltage phase angle.

_{e}value.

- G
_{i}—active generation power at node i, and - L
_{i}—active load power at node i.

- k
_{Pe}—adjustment factor that is calculated in real time during the overload state, defined by Expression (12), - S
_{MAXe}—maximum permissible apparent power of element e.

_{Pe}is introduced in order to compensate for the inaccuracy of the DC power flow model. It is calculated in real time using synchronized phasor measurements

- k
_{s}—safety coefficient with selected value 1.2, - P
_{REALe}—real-time measured active power of element e during the overload period using the PMU device, and - P
_{DCe}—calculated active power flow of element e based on the DC model during the overload period.

## 5. Case Study on an IEEE 14 Bus Test System

#### 5.1. Base Scenario

#### 5.2. N-1 Analysis

#### 5.3. DC Power Flow Model and Adjustment Factor Calculation

_{Pe}needed to be calculated in order to adjust the optimization algorithm to the real overloaded state of the network. Use of actual synchronized measurements during the overload state is recommended. Every PMU measurement has its own time tag, which makes such measurements easy to compare. As the calculations were run on the test system, synchronized measurement data were replaced by data from nonlinear AC power flow model calculations. DC power flow model data were calculated as part of the optimization algorithm. The calculation results of the IEEE 14 bus test model for the N-1 overload case are shown in Table 3.

#### 5.4. Optimal Bus-Splitting Scheme Solution—SIPS IEEE 14 B

#### 5.5. IEEE 14 Bus Test System Security Assessment

## 6. Conclusions

## Author Contributions

## Acknowledgments

## Conflicts of Interest

## References

- He, P.; Wen, F.; Ledwich, G.; Xue, Y. Small signal stability analysis of power systems with high penetration of wind power. J. Mod. Power Syst. Clean Energy
**2013**, 1, 241–248. [Google Scholar] [CrossRef] [Green Version] - Yuan, X. Overview of problems in large-scale wind integrations. J. Mod. Power Syst. Clean Energy
**2013**, 1, 22–25. [Google Scholar] [CrossRef] [Green Version] - Martin, K.E.; Hamai, D.; Adamiak, M.G.; Anderson, S.; Begovic, M.; Benmouyal, G.; Brunello, G.; Burger, J.; Cai, J.Y.; Dickerson, B.; et al. Exploring the IEEE standard C37.118-2005 synchrophasors for power systems. IEEE Trans. Power Deliv.
**2008**, 23, 1805–1811. [Google Scholar] [CrossRef] - Phadke, A.G.; Thorp, J.S. Synchronized Phasor Measurements and Their Applications; Springer: New York, NY, USA, 2008; pp. 3–27. [Google Scholar]
- Terzija, V.; Valverde, G.; Cai, D.; Regulski, P.; Madani, V.; Fitch, J.; Skok, S.; Begovic, M.M.; Phadke, A. Wide-area monitoring, protection, and control of future electric power networks. Proc. IEEE
**2011**, 99, 80–93. [Google Scholar] [CrossRef] - Ivankovic, I.; Kuzle, I.; Holjevac, N. Multifunctional WAMPAC system concept for out-of-step protection based on synchrophasor measurements. Int. J. Electr. Power Energy Syst.
**2017**, 87, 77–88. [Google Scholar] [CrossRef] - Wang, L.; Bo, Z.Q.; Ma, X.W.; Wang, Q.P.; Zhao, Y.K.; Zhou, F.Q.; Feng, X. A New Integrated Protection Scheme for Power Transmission Lines. In Proceedings of the 2017 IEEE PES General Meeting, Chicago, IL, USA, 16–20 July 2017. [Google Scholar]
- Quiros-Tortos, J.; Wall, P.; Terzija, V. Reducing excessive standing phase angle differences: A new approach based on OPF and wide area measurements. Int. J. Electr. Power Energy Syst.
**2016**, 78, 13–21. [Google Scholar] - Wang, W.; Liu, M.; Zhao, X.; Yang, G. Shared-network scheme of SMV and GOOSE in smart substation. J. Mod. Power Syst. Clean Energy
**2014**, 2, 438–443. [Google Scholar] [CrossRef] [Green Version] - Zbunjak, Z.; Kuzle, I. Possible savings in electricity transmission using wide area monitoring technologies in Croatian power transmission network. In Proceedings of the 8th International Conference on the European Energy Market, Zagreb, Croatia, 25–27 May 2011. [Google Scholar]
- Klarić, M.; Kuzle, I.; Holjevac, N. Wind Power Monitoring and Control Based on Synchrophasor Measurement Data Mining. Energies
**2018**, 11, 3525. [Google Scholar] [Green Version] - Ivanković, I.; Kuzle, I.; Holjevac, N. Wide Area Information-Based Transmission System Centralized Out-of-Step Protection Scheme. Energies
**2017**, 10, 633. [Google Scholar] [CrossRef] - Zbunjak, Z.; Kuzle, I. Advanced Control and System Integrity Protection Schemes of Croatian Power Transmission Network with Integrated Renewable Energy Sources. In Proceedings of the Eurocon 2013, Zagreb, Croatia, 1–4 July 2013. [Google Scholar]
- Shahriar, M.S.; Habiballah, I.O.; Hussein, H. Optimization of Phasor Measurement Unit (PMU) Placement in Supervisory Control and Data Acquisition (SCADA)-Based Power System for Better State-Estimation Performance. Energies
**2018**, 11, 570. [Google Scholar] [CrossRef] - Ali, Z.M.; Razavi, S.E.; Javadi, M.S.; Gandoman, F.H.; Aleem, S.H.E.A. Dual Enhancement of Power System Monitoring: Improved Probabilistic Multi-Stage PMU Placement with an Increased Search Space & Mathematical Linear Expansion to Consider Zero-Injection Bus. Energies
**2018**, 11, 1429. [Google Scholar] [Green Version] - Nuqui, R.F.; Phadke, A.G. Phasor measurement unit placement techniques for complete and incomplete observability. IEEE Trans. Power Deliv.
**2005**, 20, 2381–2388. [Google Scholar] [CrossRef] - Pal, A.; Sanchez-Ayala, G.A.; Centeno, V.A.; Thorp, J.S. A PMU placement scheme ensuring real-time monitoring of critical buses of the network. IEEE Trans. Power Deliv.
**2014**, 29, 510–517. [Google Scholar] [CrossRef] - Anderson, P.M.; LeReverend, B.K. Industry experience with special protection schemes. IEEE Trans. Power Syst.
**1996**, 11, 1166–1179. [Google Scholar] [CrossRef] - Madani, V.; Novosel, D.; Horowitz, S.; Adamiak, M.; Amantegui, J.; Karlsson, D.; Imai, S.; Apostolov, A. IEEE PSRC report on global industry experiences with system integrity protection schemes (SIPS). IEEE Trans. Power Deliv.
**2010**, 25, 2143–2155. [Google Scholar] [CrossRef] - Koglin, H.-J.; Muller, H. Overload Reduction through Corrective Switching Actions. In Proceedings of the IEE International Conference on Power System Monitoring and Control, London, UK, 24—26 June 1980. [Google Scholar]
- Van Amerongen, R.A.M.; Van Meeteren, H.P. Security Control by Real Power Rescheduling, Network Switching and Load Shedding. In Proceedings of the International Conference on Large High Voltage Electric Systems, Paris, France, 27 August—4 September 1980. Report 32-02. [Google Scholar]
- Rolim, J.G.; Machado, L.J.B. A study of the use of corrective switching in transmission systems. IEEE Trans. Power Syst.
**1999**, 14, 336–341. [Google Scholar] [CrossRef] - Wei, S.; Vittal, V. Corrective switching algorithm for relieving overloads and voltage violations. IEEE Trans. Power Syst.
**2005**, 20, 1877–1885. [Google Scholar] - Wrubel, J.N.; Rapcienski, P.S.; Lee, K.L.; Gisin, B.S.; Woodzell, G.W. Practical experience with corrective switching algorithm for on-line applications. IEEE Trans. Power Syst.
**1996**, 11, 415–421. [Google Scholar] [CrossRef] - MathWorks®. MATLAB 2016 Software. Available online: https://uk.mathworks.com/products/matlab.html (accessed on 12 February 2018).
- Purchala, K. Modeling and Analysis of Techno-Economic Interactions in Meshed High Voltage Grids Exhibiting Congestion. Ph.D. Thesis, University of Leuven, Leuven, Belgium, 2005. [Google Scholar]
- Power System Test Case Archive, University Washington. Available online: http://www.ee.washington.edu/research/pstca/pf14/pg_tca14bus.htm (accessed on 23 September 2014).
- PSS®E—High-Performance Transmission Planning and Analysis Software. Available online: https://new.siemens.com/global/en/products/energy/services/transmission-distribution-smart-grid/consulting-and-planning/pss-software/pss-e.html (accessed on 3 September 2019).

**Figure 1.**System integrity protection scheme (SIPS) based on phasor measurement unit (PMU) synchronized measurements.

**Figure 7.**Symbolic example of a bus-splitting combination on three bus systems for a bus with six initially defined elements.

**Figure 8.**IEEE 14 bus test system with PMU placement for an optimal bus-splitting protection scheme.

SIPS | SIPS Label |
---|---|

Substation | Substation name |

Bus I | List of bays that need to be connected to bus I |

Bus II | List of bays that need to be connected to bus II |

… | |

Bus N | List of bays that need to be connected to bus N |

Elements | Power Flow Limit (MVA) |
---|---|

Lines 1-2 (1), 1-2 (2), 1-5, 2-3, 2-4, 2-5, 3-4, 4-5 | 130 |

Transformers 4-7, 4-9, 5-6 | 85 |

Lines 6-11, 6-12, 6-13, 7-8, 7-9, 9-10, 9-14, 10-11, 12-13, 13-14 | 70 |

Element | From Bus | To Bus | P_{REAL} (MW) | P_{DC} (MW) | k_{Pe} |
---|---|---|---|---|---|

1 | 1 | 2 | 0 | 0 | 1 |

2 | 1 | 2 | 137.3 | 127.3 | 0.91 |

3 | 1 | 5 | 98.6 | 91.7 | 0.94 |

4 | 2 | 3 | 69.7 | 66.6 | 0.97 |

5 | 2 | 4 | 48.3 | 48 | 1 |

6 | 2 | 5 | 31 | 31.1 | 1 |

7 | 3 | 4 | −26.6 | −27.6 | 0.99 |

8 | 4 | 5 | −71.3 | −72.5 | 0.99 |

9 | 4 | 7 | 27.6 | 28.6 | 0.99 |

10 | 4 | 9 | 15.8 | 16.4 | 0.99 |

11 | 5 | 6 | 44.9 | 42.7 | 0.97 |

12 | 6 | 11 | 7.8 | 6.7 | 0.98 |

13 | 6 | 12 | 7.8 | 7.6 | 1 |

14 | 6 | 13 | 18 | 17.2 | 0.99 |

15 | 7 | 8 | 0 | 0 | 1 |

16 | 7 | 9 | 27.6 | 28.6 | 0.98 |

17 | 9 | 10 | 4.8 | 5.9 | 0.98 |

18 | 9 | 14 | 9.1 | 9.7 | 0.99 |

19 | 10 | 11 | −4.2 | −3.2 | 0.98 |

20 | 12 | 13 | 1.7 | 1.5 | 1 |

21 | 13 | 14 | 5.9 | 5.2 | 0.99 |

SIPS | IEEE 14 B |
---|---|

Bus | 2 |

Bus 21 | Line 1-2 (2), 2-3 i 2-4 and generator |

Bus 22 | Line 2-5 and load |

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**MDPI and ACS Style**

Zbunjak, Z.; Kuzle, I.
System Integrity Protection Scheme (SIPS) Development and an Optimal Bus-Splitting Scheme Supported by Phasor Measurement Units (PMUs). *Energies* **2019**, *12*, 3404.
https://doi.org/10.3390/en12173404

**AMA Style**

Zbunjak Z, Kuzle I.
System Integrity Protection Scheme (SIPS) Development and an Optimal Bus-Splitting Scheme Supported by Phasor Measurement Units (PMUs). *Energies*. 2019; 12(17):3404.
https://doi.org/10.3390/en12173404

**Chicago/Turabian Style**

Zbunjak, Zoran, and Igor Kuzle.
2019. "System Integrity Protection Scheme (SIPS) Development and an Optimal Bus-Splitting Scheme Supported by Phasor Measurement Units (PMUs)" *Energies* 12, no. 17: 3404.
https://doi.org/10.3390/en12173404