With the integration of distributed generation (DG) to meshed distribution systems, operating time protective system becomes a major concern in order avoid nuisance DG tripping. This paper proposes new time-current-voltage tripping characteristic for directional overcurrent relays (DOCRs) that can achieve higher possible reduction overall networks. The proposed is described detail. Moreover, protection coordination problem formulated as constrained nonlinear programming determine optimal...

Detection of high-resistance faults on meshed low-voltage dc grids poses a challenge, as such have very low fault current magnitudes. This paper proposes hybrid passive-overcurrent relay to overcome this problem. The proposed consists one and voltage transducer, well two passive elements: 1) an inductor; 2) capacitor. For bolted relatively low-resistance faults, the uses simple overcurrent function detect resultant high magnitudes within 2 ms. On other hand, for real-time discrete wavelet...

Fast detection of dc faults in medium-voltage (MVDC) microgrids poses a challenge as such can cause severe damage to voltage-sourced converters within few milliseconds. This paper proposes new traveling-wave (TW)-based method detect, classify, and locate different fault types MVDC microgrids. Unlike the existing TW-based protection location methods, proposed technique: (1) utilizes only first locally measured TW after inception (2) focuses on waveshape properties polarity TW, rather than its...

Usually, protection coordination problems are solved under the assumption that network topology is fixed. Yet, in practice, any power system can encounter changes due to transient events. These events be form of line or generation source outage. Furthermore, presence distributed generation, change depending on whether operating grid-connected islanded mode. Thus, it essential consider all possible topologies while designing a scheme for distribution systems with (DG). In this paper, problem...

New grid codes impose fault ride through (FRT) requirements on large doubly fed induction generator (DFIG)-based wind parks connected to transmission systems in order reduce the loss of huge generation power due temporary faults. Recently, focus is set toward development different turbine technologies enhance FRT capability with no consideration for system protection schemes. This paper proposes a new communication-based dual time-current-voltage (Dual-TCV) tripping characteristic...

Permanent power loss and major catastrophic failures are among the potential consequences of undetected faults within photovoltaic (PV) arrays. This paper proposes a voltage-based protection scheme that detects, classifies, locates string-to-ground, string-to-string, open-circuit in utility-scale PV The operates based on magnitude wave-shape properties voltage signals. Some salient features this method include its capability to distinguish between fault partial shading conditions,...

Fast dc fault detection in high-voltage (HVdc) grids is paramount due to the possibility of attaining a severely high current within few milliseconds. This article proposes new traveling-wave (TW) based protection scheme detect and locate faults HVdc grids. In contrast existing TW-based location approaches, proposed scheme, first, utilizes only first locally measured TW after inception fault, and, second, focuses on frequency content polarity TW, rather than its arrival time. The direction...

Fast dc fault detection method is required in medium‐voltage (MVDC) microgrids to avoid severe damage the interfacing converters. Ensuring selectivity and sensitivity of protection system within a few milliseconds major challenge. This study proposes new technique based on launched travelling‐waves (TWs) detect, classify, locate different types MVDC microgrids. Unlike existing TW‐based location methods, proposed utilises frequency TW reflections, rather than their arrival time. Moreover,...

Faults in inverter-based islanded microgrids can be a formidable protection challenge due to the limited fault current contribution of inverters. This paper designs selective and sensitive scheme by injecting pattern up three synthetic harmonics utilizing flexibility existing distributed generation (IBDG) controllers (called injection [IP]). The measured (MP) each relay is result combination IPs from IBDGs at different locations microgrid. To ensure that relays measure MPs for forward...

Conventional directional overcurrent relays (DOCRs) may fail to protect microgrids formed using inverter-based distributed generation (IBDG) units, as IBDGs have limited fault current contribution. Maloperation of DOCRs can be due to: 1) inability distinguish load and currents; 2) incorrect direction identification; or 3) miscoordination primary backup DOCRs. This article proposes employing harmonic injection capability design a novel DOCR (HDOCR). In the proposed method, during conditions,...

Optimal relay settings are determined where coordination constraints modelled considering only either one fault location (near end or midpoint) two locations and far end) on a feeder. This study, first, investigates whether is sufficient to guarantee proper for faults at all other The results show that violations, in the constraints, can occur various points along feeder if relays coordinated locations. In addition, multiple while determining optimal setting avoid such problem but expense of...

Line current differential relays (LCDRs) detect faults accurately and promptly, by comparing all currents flowing into the line. This type of relay has been identified in literature as a reliable protection for lines DC microgrids (MGs). LCDRs, however, lack required resiliency against cyber intrusions, such false data injection attacks (FDIAs) time synchronization (TSAs), due to their high dependence on communication infrastructure and/or Global Positioning System (GPS). paper first...

Detecting faults in DC microgrids faces numerous challenges terms of fast detection requirements, sensitivity against low- and high-resistance faults, selectivity. This paper proposes a novel local-measurement-based distance relay for that addresses these challenges. The relay's power circuit integrates an inductor at the end each line. Additionally, it employs auxiliary components with peak (PDC) capturing processing different waveforms instant fault occurrence. Local measurements voltages...

Summary form only given. With the integration of distributed generation (DG) to meshed distribution systems, operating time protective system becomes a major concern in order avoid nuisance DG tripping. This paper proposes new time-current-voltage tripping characteristic for directional overcurrent relays (DOCRs) that can achieve higher possible reduction overall networks. The proposed is described detail. Moreover, protection coordination problem formulated as constrained nonlinear...

Multi-terminal low-voltage DC (MT-LVDC) remote microgrids are subjected to faults with low current magnitudes. Although such do not disturb microgrid steady-state operation, their continuous existence can lead permanent (prm) power losses and personnel hazard. Yet, given that often temporary (tmp) on overhead lines, instantaneous de-energisation of the entire upon fault detection result in prolonged loss infeed, i.e. load. This study proposes a centralised protection scheme achieve tmp-fault...

Faults in inverter-based islanded microgrids can be a formidable protection challenge due to (i) low fault current magnitudes, (ii) compromised phase angles, and (iii) bidirectional flow of currents. This paper proposes scheme that disregards the signals altogether. Instead, it relies on decoupled synthesized introduced only during conditions. is achieved by exploiting existing distributed generation (IBDG) controllers inject synthetic harmonic voltages These are measured locally digital...

Power system benchmarks are transmission and distribution networks used to evaluate novel control algorithms simulate grid evolution scenarios. These range in size, characteristics, use cases. Although active working groups have created published many benchmarks, these not all representative of a given region may consider certain aspects such as increased penetration levels distributed energy resources. To address issues, synthetic benchmark methodologies for generating them been developed...

A reliable fault current calculation method is required to perform precise protection coordination analysis. The conventional short circuit not valid for distribution power systems that are equipped with Inverter-Based Distributed Generation (IBDG) units. This paper proposes a new simple based on the superposition theorem calculates three-phase currents meshed system in presence of IBDG proposed tested IEEE 14-bus three achieves good accuracy when compared results transient model test...

The nature of distribution systems is changing from passive to active networks due the integration Distributed Energy Resources, especially Inverter-Based Generation (IBDG). This change presents challenges for existing fuse-based unidirectional protection schemes, as experience bidirectional flow power and small fault current contribution IBDGs. Such behavior can impact scheme's sensitivity selectivity, compromising reliability leading customer outages improper isolation. problem exacerbated...

Being fast and highly reliable under different conditions, line current differential relays (LCDRs) are high-end protective devices that deployed to protect DC critical AC lines. LCDRs, however, vulnerable cyber attacks, since this type of relay is dependent on communication infrastructure the global positioning system (GPS). This susceptibility may enable attackers fool LCDRs into issuing unwarranted trip signals, potentially create an instability if several attacks coordinated. Through...

Owing to its system independence and unmatched speed, Traveling-wave (TW)-based relaying has become a top contender for transmission distribution systems. However, existing measurement devices, such as Current Transformers (CTs), are incapable of capturing the full frequency content TWs, their bandwidths limited. Consequently, TW-based schemes rely on distorted waveforms partial-frequency spectra, i.e., low-frequency content, TWs perform protection tasks. Such incomplete information can lead...

With the increased dependency on Demand Side Management (DSM) for congestion mitigation in distribution network (DN), cyber physical security of such management methods need to be investigated. DSM based distributed rely aggregators' communication consumers load profiles operator (DNO). Compromising aggregator would hence affect results. To gain insights into vulnerability methods, different attack scenarios are studied this paper assuming a compromised aggregator. Simulation results, IEEE...