PMU Placement in Electric Transmission Networks for Reliable State Estimation Against False Data Injection Attacks

Abstract

Abstract-Currently the false data injection (FDI) attack bring direct challenges in synchronized phase measurement unit (PMU) based network state estimation in wide-area measurement system (WAMS), resulting in degraded system reliability and power supply security. This paper assesses the performance of state estimation in electric cyber-physical system (ECPS) paradigm considering the presence of FDI attacks. The adverse impact on network state estimation is evaluated through simulations for a range of FDI attack scenarios using IEEE 14-bus network model. In addition, an algorithmic solution is proposed to address the issue of additional PMU installation and placement with cyber security consideration and evaluated for a set of standard electric transmission networks (IEEE 14-bus, 30-bus and 57-bus network). The numerical result confirms that the FDI attack can significantly degrade the state estimation and the cyber security can be improved by an appropriate placement of a limited number of additional PMUs. Index Terms-Phase

Integrated Approach for Network Observability and State Estimation in Active Distribution Grid

“…For instance, inclusion of PMU will not have any impact on the observability analysis proposed in this paper, since the algorithm is based on the number and locations of the measurements, not on their dynamic behavior. However, the proposed bus prioritization technique can be useful for identifying the critical locations at which to place the PMUs in the network, not only improving the accuracy of state estimation, but also defending against data injection attacks with minimum cost [21]. This could be possible either by treating PMU measurements as additional measurements in the traditional data set (this will add the computational burden) or the using distributed computation of mixed/hybrid state estimation [40].…”

“…Therefore, to linearize the problem, the measured phasors in polar form can be converted to an equivalent rectangular form. Key challenges due to the inclusion of PMU measurements include: false data injection attack in the wide area measurement system [21], convergence problem of the hybrid state estimator during the iterative process due to uncertainty introduced by the instrument transformers, their connection with digital equipment and A/D converters [22], etc. On the other hand, to overcome the limitation of real measurements, when large number of virtual measurements (that may have significant uncertainties) are used to make the network observable, there is a high possibility of system states deviating from their actual values.…”

A Probabilistic Multi-Objective Model for Phasor Measurement Units Placement in the Presence of Line Outage

“…By analyzing the data in Table 3, it can be seen that the difference of the placement schemes between the two models lies in the locations of the PMUs. For example, 29 PMUs are needed in both models under case 2, and the majority of PMUs are placed at the same location, namely, bus 1, 3,9,12,20,22,24,27,29,30,32,33,35,39,47,51,53,55,57; meanwhile, the rest few PMUs are placed at a different location, namely, bus 4,6,11,15,19,36,41,44,46,49 in multi-objective model and bus 5,7,14,18,38,40,42,43,45,50 in single-objective model. Obviously, the sum of adjacent buses of bus 4,6,11,15,19,36,41,44,46,49 is larger than bus 5,7,14,18,38,40,42,43,45,50. Thus, compared to single-objective models, parts of PMUs in multi-objective models are placed at the buses with more adjacent buses.…”

“…Apparently, the developed placement model can provide solutions with higher reliability. ,11,12,15,19,20,22,24,26,28,29,30,31, 32,33,35,36,37,38,41,45,46,47,50,51,53,54,56,57 Multi-objective 29 0.00180 1,3,4,6,9,11,12,15,19,20,22,24,27,29,30,32,33,35,36,39,41,44,46,47,49,51,53,55,57 Single-objective 29 0.00298 1,3,5,7,9,12,14,18,20,22,24,27,29,30,32,33,35,38,39,40,42,43,45,47,…”

“…The wide-area measurement system (WAMS) was developed to provide real-time data for state estimator with high precision and great efficiency, in order to further guarantee the power system stability [1] and meet the requirement of a rapid increase in energy demand [2,3]. Phasor measurement units (PMU) can measure voltage phasor at the bus as well as current phasors of incident branches, thereby guaranteeing the observability of the bus where it is located and its adjacent buses [4][5][6]. In addition, due to restrictions of finance and technology, it is neither necessary nor economic to place PMU at each bus to assure the system becomes observable [7].…”