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The rapid evolution of sensor technologies and communication networks is tightly coupling the cyber and physical layers of power systems. Because a few power grids have fallen victim to cyber intrusions causing unexpected device failure and large-scale power outages, enhancing power system cybersecurity is the utmost focus of power grid development today. Financially, the deregulation of the electricity market opens the gate to profit-oriented cyberattacks. Real-time market auctions rely heavily on the accuracy of state estimation, which is susceptible to cyberattacks. Extensive reviews have been conducted on modern power system cybersecurity. However, the lack of a comprehensive and in-depth review of electricity market cyberattacks prevents independent system operators from systematically analyzing the financial consequences of cyberattacks and limits public awareness of the significant monetary loss. This article briefly summarizes previous review works and analyzes the two-settlement market design from a cybersecurity perspective. Then the current achievements of electricity market cyberattacks are discussed, and state-of-the-art works are analyzed based on their contributions. Additionally, a few possible improvements and future directions are presented. [ABSTRACT FROM AUTHOR]

Traditional cyberattack strategies on the electricity market only consider bypassing bad data detections. However, our analysis shows that experienced market operators can detect abnormal locational marginal prices (LMPs) under the traditional attack model during real-time (RT) operations, because such attack model ignores the characteristics of the LMP itself and leads to price spikes that can be an easy-to-detect signal of abnormality. A detection approach based on the concept of critical load level (CLL) is used to help operators identify risky periods when operators would be prone to overlooking abnormal LMPs. During safe periods, the abnormal LMPs are identified according to the operator's experience, while in risky CLL intervals, a N-x cyber contingency analysis is proposed to help independent system operators (ISOs) detect abnormal LMPs. Further, this paper constructs a new type of cyberattack strategy capable of not only bypassing bad data detection in the state estimation stage but also disguising the compromised LMPs as regular LMPs to avoid market operators’ alerts in a realistic scenario wherein the attacker has imperfect information on system topology. Finally, the proposed analysis method and the attack strategy are evaluated through numerical studies on the PJM 5-bus system and the IEEE 118-bus system. [ABSTRACT FROM AUTHOR]

In this paper, we integrate programmable networks in microgrid (MG) to provide flexible and easy-to-manage communication solutions, thus enabling resilient MG operations in face of various cyber and physical disturbances. Specifically, two contributions have been made: 1) establish a novel software-defined networking (SDN) based communication architecture that abstracts the network infrastructure from the upper-level applications to significantly expedite the development of MG applications and 2) create a hardware-in-the-loop cyber-physical platform for evaluating and validating the performance of the presented architecture, control techniques, and SDN-based functionalities. Test results have demonstrated that the new architecture can significantly enhance MG resilience, particularly for those that have high penetration of renewable energy sources. [ABSTRACT FROM PUBLISHER]

A salient feature of a renewable energy power supply system (REPSS) on islands is the high level of uncertainties caused by high penetration of volatile power sources, such as wind and solar photovoltaic farms. This creates large forecast errors under some conditions and makes the fixed time-scale dispatch impotent in maintaining system reliability. To tackle this challenge, a time-scale adaptive dispatch method is developed in this paper. The time-scale for dispatch REPSS on islands is adjusted online according to the confidence interval of forecast error predicted by neural network. Extensive tests have validated the effectiveness of the presented method in offsetting the uncertainties in the system and improving the system reliability. [ABSTRACT FROM PUBLISHER]

Recently, a new oscillation phenomenon—intermittent subsynchronous oscillation (ISSO)—has been observed in a large interconnected power grid. Rather than leading to oscillatory instability, ISSO causes cumulative fatigue damage and reduces the shaft life of the generator. The existing phase-compensation-based damping technologies are found to be limited in mitigating these types of oscillations. To mitigate ISSO, a subsynchronous modulation of reactive current (SMRC) approach is established and implemented in the voltage-source converters (VSCs) at the generator terminals. The contribution of SMRC to system damping has been analyzed in order to select control parameters for the VSC. The SMRC controller has been prototyped and extensively tested on a real-time closed-loop simulation platform equipped with a newly developed speed sensor module for precisely interfacing the real-time digital simulator with the rotating speed-acquisition board. Extensive experiments on the input and output characteristics of the VSC have been carried out to test and validate the damping current generating module. The effective damping areas are obtained from test observations to fine tune the parameters of the VSC controller for adapting to various system operating conditions, resulting in the common optimal damping region. Real-time simulations, onsite commissioning, and statistics have demonstrated the ability of the SMRC to mitigate ISSO and subsynchronous oscillation in power plants. [ABSTRACT FROM PUBLISHER]

Power flow analysis for islanded microgrid is a challenging problem due to the lack of means to incorporate the hierarchical control effect. This letter bridges the gap by devising a generalized microgrid power flow (GMPF). The novelty of GMPF includes: 1) it introduces the generalized distributed generator (DG) bus and the adaptive swing bus to model the DGs’ behaviors; 2) the droop-based power flow is used to initialize the secondary control adjustment; and 3) three types of secondary control modes are developed within a double loop framework. Test results validate the effectiveness and excellent convergence performance of GMPF. [ABSTRACT FROM AUTHOR]