Distribution networks are evolving towards the vision of smart grids, with increasing penetration Distributed Generation (DG), introduction Active Network Management (ANM) and potentially islanded modes operation.These changes affect both fault levels current paths have been demonstrated to compromise correct operation overcurrent protection system.This paper presents an adaptive system which automatically amends settings all relays in response impact DG, ANM islanding operation.The scheme...

Inverter dominated microgrids impose significant challenges on the distribution network, as inverters are well known for their limited contribution to fault current, undermining performance of traditional overcurrent protection schemes.This paper introduces a new scheme based initial current traveling wave utilizing an improved mathematical morphology (MM) technology, with simplified polarity detection and logics introduced meshed networks feeders single-end measurement.The proposed provides...

High-voltage direct-current (HVDC) systems are being widely employed in various applications because of their numerous advantages such as bulk power transmission, efficient long-distance and flexible power-flow control. However, line-commutated-converter-based HVDC suffer from commutation failure, which is a major drawback, leading to increased device stress interruptions transmitted power. This paper proposes predictive control strategy, deploying failure prevention module mitigate the...

This paper presents a method for rapid detection of faults on voltage source converter multiterminal HVdc transmission networks using multipoint optical current sensing. The proposed uses differential protection as guiding principle, and is implemented measurements obtained from the sensors distributed along line. Performance assessed through detailed transient simulation MATLAB/Simulink models, integrating inductive dc-line terminations, dc circuit-breaker network fiber-optic sensors....

When faults occur in the microgrids, high frequency transients will be superimposed on system currents and voltages. The magnitude of those attenuate as it encounters discontinuity points network such busbars, or any other impedance points. This phenomenon can also quantified by wavelet energy, which provides a useful tool to detect locate faulted feeder microgrid. In this paper, novel protection scheme based transient energy current extracted Maximal Overlap Discrete Wavelet Transform...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A step-by-step coordinated design procedure for power system stabilisers (PSSs) and automatic voltage regulators (AVRs) in a strongly coupled is described this paper. It shown that it possible to separate the of individual PSSs AVRs. Thereby, designs AVR PSS devices at given machine can be achieve near-optimal overall stability performance, including oscillation performance transient performance....

This paper presents a new method for locating faults in multi-terminal direct current (MTDC) networks incorporating hybrid transmission media, including segments of underground cables and overhead lines. The proposed traveling wave type uses continuous wavelet transform applied to series line measurements obtained from network distributed optical sensors. technical feasibility optically-based dc measurement is evaluated through laboratory experiments using Fiber-Bragg Grating sensors other...

Two tradeoffs in the effectiveness of automatic voltage regulators (AVRs) and power system stabilizers (PSSs) are investigated together for first time. The is effect a high-gain fast response AVR on decreasing oscillation stability as well increasing transient stability, vice versa. second that PSS can reduce by overriding signal to exciter In essence, actions devices dynamically interlinked. A novel Bode frequency framework dynamic analysis performance presented. also assists with...

Conventional converter models for wind turbines and Voltage Source HVDC links, as submitted to System Operators, typically use dq-axis controllers with current injection (DQCI). Recent work carried out by the authors has proven that DQCI converter-interfaced sources there are overall penetration limits, i.e. 'tipping points' beyond which system will become unstable. Initial investigations of this "tipping point", based on a reduced model transmission Great Britain using phasor simulation...

All conventional techniques for measuring frequency result in large deviations to the perceived or calculated when AC waveform undergoes a phase step. The deviation magnitude and duration are dependent on step magnitude, applied windowing/filtering. Such steps do occur power system, erroneous calculation can inappropriate reactions by some rapidly-responding control protection systems. If measurand is further differentiated ROCOF (Rate of Change Frequency), excursion magnitudes become far...

A decentralized voltage control is proposed for distributed generation (DG) units to provide short and long-term support in distribution networks. Local controllable zones are used determine the boundaries each DG unit. The number of their size depend on number, location units, can be reconfigured real time response network topology changes. performance value approach demonstrated under various operating scenarios. study based IEEE 33-bus radial implemented DIgSILENT PowerFactory.

The installed capacity of non‐synchronous devices (NSD), including renewable energy generation and other converter‐interfaced equipment is expected to increase contribute a large proportion total in future power systems. Concerns have been expressed relating operability stability such systems, since NSD are typically decoupled from the grid via electronic consequently reduce ‘natural’ inertia, short‐circuit levels damping which inherently provided by synchronous machines. This study...

Fault detection and protection of Superconducting Cables (SCs) is considered a challenging task due to the effects quenching phenomenon High Temperature (HTS) tapes prospective magnitude fault currents in presence highly-resistive faults converter-interfaced generation. This paper presents novel, time-domain method for discriminative power system incorporating SCs high penetration renewable energy sources. The proposed algorithms utilizes feature extraction tools based on Stationary Wavelet...

The growing penetration of converter interfaced generation creates unprecedented challenges to protection strategies at all voltage levels. This paper proposes a novel Negative Sequence Current Injection (NSCI)-based active scheme for islanded microgrids. faulty section identification method based on the negative sequence current increment between pre-injection and steady state conditions enables achieve an excellent High Impedance Fault (HIF) detection capability. proposed NSCI control...

Increased penetration of distributed generation (DG) will impact on power network protection systems. Many publications present solutions to problems such as blinding, false tripping and loss grading for networks incorporating DG, but neglect fully quantify demonstrate the that are being addressed. This study fills a gap in understanding particular problem blinding through presenting detailed DG overcurrent using typical UK rural distribution network. considers all relevant factors, as:...

Large-scale integration of different renewable energy resources introduces significant challenges to the protection microgrids (particularly those that may operate in islanded mode), including variable and low fault levels, difficulty operation main backup with their coordination, bidirectional power flow during faults. As a solution such challenges, this paper presents novel active strategy for inverter dominated coordinates actions control strategy. The proposed scheme dictates specific...

This paper presents the development of a novel data-driven fault detection and classification scheme for DC faults in multi-terminal HVDC transmission system which incorporates superconducting cables modular multi-level converters. As deployment bulk power from remote renewable generation is progressively increasing future energy grids, many fault-related challenges have been raised (i.e., detection, protection sensitivity/stability). In this context, applications Artificial Intelligence...

This paper presents a comprehensive study to investigate the travelling wave protection performance in network s with high penetration of Converter-Based Resources (CBRs). Representative models are developed sub-step environment Real-Time Digital Simulator (RTDS) and realistic Hardware-in-the-Loop (HiL) tests conducted on pair relays (TWRs) emulate system fault scenarios. The studies have been two stages: firstly, systematic total number 300 cases high-level assessment TWRs' under different...

Unique and varied power system conditions are already being experienced as a result of the deployment novel control strategies new generation distribution related technologies driven by smart grid. A particular challenge is to ensuring correct reliable operation protection schemes. Implementing smarter in form adaptive setting selection one way tackling some performance issues. However, introducing such approaches especially safety critical systems carries an element risk. Furthermore,...

This study presents a method for discriminative detection of direct current (DC) faults on voltage source converter-powered multi-terminal high-voltage transmission systems using two fundamental guiding principles, namely instantaneous current-differential and travelling waves. The proposed algorithm utilises local measurements from all lines connected to DC busbar, measurement the side converter. scheme operates at sampling frequency 96 kHz, which conforms with IEC 61869-9. No long distance...

The DC-side line faults in high-voltage direct-current (HVDC) systems utilising voltage-source converters (VSCs) are a major concern for multi-terminal HVDC which complete isolation of the faulted system is not viable option.A number challenges posed by both pole-to-pole and pole-to-ground including presence very fast high amplitude discharge current from DC-link capacitance, lack suitable DC breaking devices, highly discriminative fault detection techniques.Therefore, occurring along...