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This paper develops a parameter-free fault location (FL) method for double-circuit transmission lines utilizing pre- and post-fault unsynchronized current and voltage measurements. Firstly, the FL equation is deduced for normal-shunt and non-identical inter-circuit faults (involving different phases in both circuits). The FL equation relies on equating the voltage phasors’ difference between identical phases in the two circuits at the FL without utilizing the line parameters and synchronization angle between both line terminals. Next, the FL equation is deduced for identical inter-circuit faults (involving identical phases in both circuits) utilizing pre- and post-fault measurements, where a new method is introduced to obtain the pre-fault synchronization angle and line shunt-admittance relying on pre-fault data. Besides, it considers different synchronism mismatch in the pre- and post-fault data. To distinguish identical inter-circuit faults from other fault types, the absolute difference, between post-fault currents of identical phases in both circuits at each line terminal, is employed. PSCAD/EMTDC software is used for modeling the IEEE 39-bus system to evaluate the proposed method for various fault resistances, locations, fault types, and measurement errors. In addition, the developed method offers solid performance against evolving faults and different loading conditions. Moreover, it remains applicable when one of the two circuits is out-of-service.

This paper compares and evaluates the cost, performance, and reliability of an existing three-phase synchronous reluctance machine (SynRM) drive system when it is revamped by doing at least one of the twofold 1) replacing the three-phase winding by either a star-connected or combined star-pentagon five-phase winding and/or 2) inserting ferrite permanent magnet (PM) in the rotor barriers. In addition to the existing three-phase SynRM drive, this recycling yields five revamped drive systems. The comprehensive study of the recycling was carried out using Ansys Maxwell Transient Simulation and MATLAB Simulation. The comparison revealed that the star-pentagon five-phase PMa-SynRM drive outperformed the others in terms of performance and reliability. It offers 28.9% higher average torque, 32.75% lower torque ripple, 20.98% higher power factor, 40% less common mode voltage and 1.94% more efficient than three-phase SynRM drive at healthy rated condition. Furthermore, at one-phase fault, it has an 81.5% lower torque ripple and 145% higher average torque than the three-phase SynRM drive, therefore being the most reliable drive system. For the combined cost of machine and converter, star-pentagon five-phase PMa-SynRM drive is only 2.25% more expensive than three-phase SynRM drive. Moreover, this comparison has been experimentally validated.

The utilization of hydrogen-powered vehicles as an alternative to fossil-fueled ones has been identified as a promising solution to reduce greenhouse gas emissions. To promote the deployment of hydrogen-powered vehicles, however, it is imperative that hydrogen refueling stations with on-site electricity-produced hydrogen (eHRSs) are economically utilized for concurrent services. Therefore, this article proposes a new estimation-based method for the optimal scheduling of eHRS for the provision of congestion management services to the distribution system. The method allows for real-time adaptive management of the congestion level in the feeder as decided by the distribution system operator. A new correlation-based method is proposed for online estimation of the amount of congestion and determination of the eHRSs setpoints to relieve congestion on the distribution feeders. This article also develops a congestion management pricing mechanism for the compensation of eHRSs that serve the distribution grid. Numerical results indicate how distribution feeder congestion can be adaptively managed, while the financial profile of the eHRSs is improved via joint application and provision of concurrent services to the transportation sector and grid operator.

Due to high penetration of renewable energy sources, inter-area oscillations (IAOs) have become serious concern for power system stability. Hence, a wide-area damping controller (WADC) strategy is proposed for thyristor-controlled series compensator (TCSC) device to effectively damp IAOs. The feedback signals for the WADC design are selected by the modal sparse linear quadratic regulator (MSLQR) method, which are sole signals that modulate simple gains to achieve the desired damping performance. Moreover, the multi-model framework approach is adopted to ensure optimal damping corresponding to any uncertainties such as changing operating scenarios and time latency in feedback signals. However, the proposed primary control does not provide frequency regulation; hence, a secondary control based on the switched integral controller is applied in addition to primary damping control to further maintain the frequency at the steady-state level. Performance of suggested strategy is evaluated and verified on IEEE 4-machine, 11-bus system and 16-machine, 68-bus system. A comprehensive analysis shows significant improvement in the damping performance of concerned modes, leaving the local modes almost unaffected while maintaining the frequency at the prescribed steady-state level.

Industrial advancements in information and communications technology facilitated the widespread use of line current differential relays (LCDRs) for protecting critical transmission lines due to their fast, sensitive, selective, and secure performance. Despite their advantages, LCDRs' reliance on vulnerable communication networks to swap current measurements makes them vulnerable to cyberattacks. In this article, a scheme is proposed to protect LCDRs from direct-false-tripping (DFT), fault-masking (FM), and sympathetic-tripping (ST) cyberattacks, which have not been studied together before for transmission-level LCDRs. The proposed scheme utilizes a deep neural network (DNN), trained offline on features extracted from only the measurements available for LCDRs. The trained DNN model can then be implemented within LCDRs. Unlike the previous solutions, which only differentiate between faults and DFT cyberattacks, the proposed scheme actively differentiates between authentic and manipulated LCDR measurements to detect and mitigate possible cyberattacks. The performance of the proposed scheme is evaluated using the IEEE 39-bus benchmark system. Our results show that the proposed scheme can accurately detect different forms of DFT, ST, and FM cyberattacks while maintaining the LCDR's protective characteristics. The proposed scheme is tested for real-time capability using an OPAL-RT simulator.