Wide Area Monitoring, Protection And Control System Research Articles

Assessing Hardware in the Loop Approaches for Wide-Area Monitoring Control and Protection Devices

Wide-area monitoring, protection, and control (WAMPAC) systems are expected to support the transmission system operators in maintaining stability and security of supply in the future power systems. The WAMPAC solutions heavily rely on deployment and use of phasor measurement units (PMU) and related communication technologies. Laboratory testing in a realistic environment utilizing hardware in the loop (HIL) approaches can be successfully used to evaluate WAMPAC functionalities algorithms and to accelerate proofs of concept. However, different implementations of the HIL testing can be adopted and their inherent characteristics affect both the accuracy of the results and the overall testing capabilities. The objective of this paper is to provide a comparative assessment of three HIL approaches for laboratory testing of WAMPAC systems and devices. These testing approaches have been implemented in a laboratory configuration and applied to characterize WAMPAC devices. Moreover, methodologies to quantify the error introduced by these testing approaches in static and dynamic conditions are presented and applied to this laboratory configuration.

The ECCANDE Project: Design, Field Implementation, and Operation of a Special Protection Scheme Based on Synchronized Phasor Measurements

This paper presents the ECCANDE project, one of the first Special Protection Schemes (SPS) conceived to rely on the structure of a Wide-Area Monitoring, Protection, and Control System (WAMPACS) and currently operating in a real, large-sized power system. This project was developed and implemented to enable the interconnection between the Argentinean and Paraguayan bulk power transmission systems, which involves and directly affects two of the largest hydropower plants in the world (the Itaipu and Yacyreta power plants). Building this WAMPACS-based SPS took more than a decade of work performed by multiple teams, involving modeling, planning studies, design, manufacturing, real-time hardware-in-the-loop (HIL) simulation for equipment testing, implementation, commissioning, field tests and evaluation of daily operation. The paper describes how system stability problems (detected during the initial studies for the interconnection) made it clear that the ECCANDE SPS had to be a WAMPACS-based one, and how its architecture and logic functions were conceived to deal with these problems. The results of HIL real-time simulations and a main field test show that the ECCANDE SPS enabled the interconnection, successfully protecting against the loss of synchronism between the Itaipu and Yacyreta power plants before the system separation.

Security of Wide-Area Monitoring, Protection, and Control (WAMPAC) Systems of the Smart Grid: A Survey on Challenges and Opportunities

The evolution of power generation systems, along with their related increase in complexity, led to the critical necessity of Wide-Area Monitoring, Protection, and Control (WAMPAC) systems in today’s smart grid. Recent developments in smart measurement devices coupled with data communication technologies allow for significant improvements in power systems’ reliability, efficiency, and security. These technological advancements make WAMPAC systems of significant practical interest. However, the geographically distributed nature of such systems increases the potential attack surface and the risk of critical vulnerabilities. Thus, it is of paramount importance to identify the related threats and vulnerabilities as well as the prominent solutions relevant to WAMPAC systems. Consequently, this paper aims to provide a comprehensive review of WAMPAC security aspects along with the state-of-the-art research initiatives addressing such aspects. Specifically, this paper provides critical taxonomies of the cyber-security scope of WAMPAC that guide the accompanying survey of the recent studies on the WAMPAC security domain. As such, this article aims to pave the way for prospective researchers to pursue further studies in areas that require in-depth investigation into the security, reliability, and efficiency of WAMPAC as the backbone of smart grids.

Construction and Evaluation of an Optical Medium Voltage Transducer Module Aimed at a 132 kV Optical Voltage Sensor for WAMPAC Systems.

This paper reports on the construction and characterization of an optical voltage transducer module for applications in the field of wide-area monitoring, protection, and control (WAMPAC). The optical medium voltage transducer (MVT) module was designed to be combined with a capacitive voltage divider (CVD) to form a voltage sensor intended for 132 kV high voltage (HV) networks. The MVT module comprises a combination of a piezoelectric transducer (PZT) and a fiber Bragg grating (FBG) as a core optical sensing element. Changes in the input voltage across the PZT translate into strain being detected by the FBG. The resultant FBG peak wavelength can be calibrated in terms of the input voltage to obtain a precise voltage measurement. The module was experimentally evaluated in the laboratory, and its performance was assessed based on the requirements specified by the IEC standards for electronic voltage transformers and low power voltage transformers. The results of accuracy tests demonstrate that the MVT module is free from hysteresis, within the experimental error, and is capable of simultaneously meeting the requirements for 0.1 metering and 1P protection classes specified by the IEC 60044-7 and IEC 61869-11 standards.

Application of IIA Method and Virtual Bus Theory for Backup Protection of a Zone Using PMU Data in a WAMPAC System

Many wide area monitoring, protection, and control (WAMPAC) systems are being deployed by grid operators to deal with critical operational conditions that may occur in power systems. Thanks to the real-time measurements provided by a set of distributed phasor measurement units (PMUs), different protection algorithms can be run in a central location. In this context, this article presents and validates a novel method that can be used as a backup protection for a selected area in a power system. It merges the integrated impedance angle (IIA) protection method with the theory of virtual buses in wide area electrical power systems. The backup protection works this way: once a fault is detected (pickup time), another delay (added to the pickup time) is defined in order to wait for the primary protection to act. If this does not happen, the algorithm generates its backup trip. The proposed method has been called the zone integrated impedance angle (Zone IIA). A real-time PMU laboratory has been used to test the proposed algorithm using a real-time digital simulator (RTDS). The algorithm has been programmed in a real-time automation controller (RTAC). It has been tested in two different simulated setups: first, a 400 kV transmission system, with and without the use of renewable energy sources (RES); second, a 150 kV submarine line between the Greece mainland and an island, which is currently the longest submarine alternating current connection in the world. The results obtained during the tests have yielded tripping times for area protection in the order of 48 ms, if no time delay is used between the fault detection and the trip order. According to the test results, the proposed method is stable, reliable, obedient, and secure, also with RES installed in the power system. Additionally, the method is selective, i.e., during the tests no trip was executed for external faults, no trip was executed in no-fault condition, and all the applied internal faults were detected and tripped correctly. Finally, the protection method is easy to implement. The method is also applicable to protection against short circuits in distribution systems. According to the trip times observed during the tests, it is clear that these algorithms are well suited to implement backup protections in transmission grids, even in scenarios with high penetration of renewable energies. Considering that backup trip times in transmission grids are usually set between 400 and 1000 ms, and that the actuation times obtained by the proposed algorithm are under 100 ms, the method is suitable for its use as a backup protection.

Wide area monitoring, protection, and control application in islanding detection for grid integrated distributed generation: A review

The assimilation of Distributed Generation (DG) into the electric power system (EPS) has become more attractive as the world is following a trend to reduce greenhouse gas emissions by introducing more renewable energy forms resulting in high penetration scenarios. This high penetration of DGs brings several challenges to the protection philosophy of the EPS which compromises its reliability, availability, and efficiency. Under high DG penetration scenarios, conventional islanding detection methods (Idms) fail to detect an island as the grid loses its inertia to leverage a significant frequency and voltage mismatch necessary for Idms to effectively detect an islanding event. This has given rise to the birth of Artificial Intelligent (AI) methods that are found to perform better in islanding detection. AI Idms are computationally intensive and require a lot of data to operate accurately. Because the computational burden of these methods requires fast computing hardware, the current trend of AI Idms are integrated with Wide Area Monitoring, Protection, and Control (WAMPAC) system. This paper aims at reviewing all these Idms and the WAMPAC’s system latency when hosting AI Idms which are currently the best in islanding detection. This is done to determine if the WAMPAC system latency plus Idms computational time meet the islanding detection time specified by the IEEE Standard 1547 framework.

Real‐time data‐assisted replay attack detection in wide‐area protection system

The cyber-attack surface in the power grid has widened with the deployment of the wide-area monitoring, protection, and control (WAMPAC) system. Replay attacks are one of the most challenging attacks to detect in a WAMPAC system. The authors aim to address the problem of identification and repercussions of continuous replay attacks on wide-area backup protection schemes. The continuous replay attacks introduce a permanent lag in the phasor measurement unit (PMU) data. The authors classify such attacks into small, medium, and wide-scale based on the number of compromised substations. Furthermore, the signature of a replay attack is derived using a one-step-ahead prediction of PMU data. The resulting forecast error distributions are subsequently analysed using the Kullback–Leibler divergence metric. Results using field PMU data show that this method successfully distinguishes replay attacks from normal system operation and faults in the system. Therefore, the proposed scheme can be used to detect and mitigate the effects of replay attacks on wide-area protection schemes.

Wide area monitoring system for an electrical grid

Power Sector is the back bone of the economy of a nation. In the day to day scenario power plays a vital role and it is the basic amenity of any sector. The power supply should be of good quality, highly reliable, cheap etc. Modern Power System is close to the stability operation, as the Distributed Generations have increased widely, and the Power Network has been extended by laying newer Transmission Lines etc., which has eventually led to the complexity in the operation and control of the Power Network. The lack of monitoring and appropriate control may lead to catastrophic failure of the network known as blackout. It occurs due to a series of outage in the system. The trend in the power network sees advanced longer paths to meet the existing demand and one such trend is the WAMPAC systems. The congestion and complexity in the network have pushed the grid to enhance for proper monitoring and control by Wide Area Monitoring Protection and Control (WAMPAC), an enabler of the Smart Grid which is a bidirectional network that can heal itself in case of any failure.

Algorithm for Fast and Efficient Detection and Reaction to Angle Instability Conditions Using Phasor Measurement Unit Data

In wide area monitoring, protection, and control (WAMPAC) systems, angle stability of transmission network is monitored using data from phasor measurement units (PMU) placed on transmission lines. Based on this PMU data stream advanced algorithm for out-of-step condition detection and early warning issuing is developed. The algorithm based on theoretical background described in this paper is backed up by the data and results from corresponding simulations done in Matlab environment. Presented results aim to provide the insights of the potential benefits, such as fast and efficient detection and reaction to angle instability, this algorithm can have on the improvement of the power system protection. Accordingly, suggestion is given how the developed algorithm can be implemented in protection segments of the WAMPAC systems in the transmission system operator control centers.

Multifunctional WAMPAC system concept for out-of-step protection based on synchrophasor measurements

Transmission network control and protection system can be enhanced using synchrophasor measurement data. Wide Area Monitoring, Protection and Control (WAMPAC) systems incorporate three levels of protection functions. The first layer is the basic relay protection, the second layer is the central system protection with wide area protection functions (WAP) and the final layer is the power system control level. Centralized protection can use new methods based on synchrophasor data. The phasor data benefits protection functions of both the second and the third layer. Therefore, to investigate the operation of the different protection functions in a centralized system, a multifunctional Matlab simulation environment is developed and presented in this paper. The model is developed using the experience from the real-time operation and was additionally expanded with new function sets that are also described. Real-time operation measurements from various disturbances are used to validate the model. Validated model is then applied to perform a series of simulations of various events in different conditions in the transmission network, such as breaker operation, short circuit faults and power oscillations. Conducted simulations provide foundations and indicators for the development and definition of criteria needed to implement enhanced central protection system resilient to all disturbances.

Roadmap for the deployment of WAMPAC in the future GB power system

This study presents a specific roadmap for the deployment of a wide area monitoring, protection, and control (WAMPAC) system in the future Great Britain (GB) power system. The specific roadmap is designed based on a generic roadmap, which draws on international experience with the development of WAMPAC systems, and a study of the changes in the GB power system. Based on this, the proposed specific roadmap identifies wide area oscillation monitoring as a key short term goal for the GB WAMPAC system and wide area oscillation control as a key long term goal for the GB WAMPAC system. To verify that this short term goal can be delivered simulations of a complete model of the GB power system that demonstrate that a new method based on a Newton Type algorithm will be more than capable of providing accurate oscillation monitoring in the GB WAMPAC system. Furthermore, for the same complete GB model it is demonstrated that the West coast CSC HVDC link can be used to create a powerful tool for oscillation damping that, with further research, should be capable of delivering the long-term goal of wide area oscillation control as part of the specific GB WAMPAC roadmap.

IP系汎用・標準技術を用いた広域系統監視・保護制御システムの開発と検証

This paper proposes a network system architecture for next-generation wide-area monitoring, protection and control (WAMPAC) of power systems, featuring a wide-area Ethernet (L2-network) and time synchronization such as IEEE 1588 and other schemes associated with decentralized modular devices. Based on the architecture, a prototype WAMPAC system has been constructed and installed in an analog power system simulator to examine its communication performance, including time synchronism and show the validity of an actual application, wide-area integrated primary and backup protection with a current differential scheme. Fundamental analyses with respect to end-to-end transmission delay, system unavailability and scalability for double redundant current differential line protection systems with 4-repeater/5-span communication links were conducted to examine its applicability to an actual power system.

Wide-Area Monitoring, Protection, and Control of Future Electric Power Networks

Wide-area monitoring, protection, and control (WAMPAC) involves the use of system-wide information and the communication of selected local information to a remote location to counteract the propagation of large disturbances. Synchronized measurement technology (SMT) is an important element and enabler of WAMPAC. It is expected that WAMPAC systems will in the future reduce the number of catastrophic blackouts and generally improve the reliability and security of energy production, transmission, and distribution, particularly in power networks with a high level of operational uncertainties. In this paper, the technological and application issues are addressed. Several key monitoring, protection, and control applications are described and discussed. A strategy for developing a WAMPAC system in the United Kingdom is given as well.