| 1. |
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| 2. |
- Li, Wei, et al.
(författare)
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Non-lab and semi-lab algorithms for screening undiagnosed diabetes : A cross-sectional study
- 2018
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Ingår i: EBioMedicine. - : ELSEVIER SCIENCE BV. - 2352-3964. ; 35, s. 307-316
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Tidskriftsartikel (refereegranskat)abstract
- Background: The terrifying undiagnosed rate and high prevalence of diabetes have become a public emergency. A high efficiency and cost-effective early recognition method is urgently needed. We aimed to generate innovative, user-friendly nomograms that can be applied for diabetes screening in different ethnic groups in China using the non-lab or noninvasive semi-lab data. Methods: This multicenter, multi-ethnic, population-based, cross-sectional study was conducted in eight sites in China by enrolling subjects aged 20-70. Sociodemographic and anthropometric characteristics were collected. Blood and urine samples were obtained 2 h following a standard 75 g glucose solution. In the final analysis, 10,794 participants were included and randomized into model development (n - 8096) and model validation (n = 2698) group with a ratio of 3:1. Nomograms were developed by the stepwise binary logistic regression. The nomograms were validated internally by a bootstrap sampling method in the model development set and externally in the model validation set. The area under the receiver operating characteristic curve (AUC) was used to assess the screening performance of the nomograms. Decision curve analysis was applied to calculate the net benefit of the screening model. Results: The overall prevalence of undiagnosed diabetes was 9.8% (1059/10794) according to ADA criteria. The non-lab model revealed that gender, age, body mass index, waist circumference, hypertension, ethnicities, vegetable daily consumption and family history of diabetes were independent risk factors for diabetes. By adding 2 h post meal glycosuria qualitative to the non-lab model, the semi-lab model showed an improved Akaike information criterion (AIC: 4506 to 3580). The AUC of the semi-lab model was statistically larger than the non-lab model (0.868 vs 0.763, P < 0.001). The optimal cutoff probability in semi-lab and non-lab nomograms were 0.088 and 0.098, respectively. The sensitivity and specificity were 76.3% and 81.6%, respectively in semi-lab nomogram, and 72.1% and 673% in non-lab nomogram at the optimal cut off point. The decision curve analysis also revealed a bigger decrease of avoidable OGTT test (52 per 100 subjects) in the semi-lab model compared to the non-lab model (36 per 100 subjects) and the existed New Chinese Diabetes Risk Score (NCDRS, 35 per 100 subjects). Conclusion: The non-lab and semi-lab nomograms appear to be reliable tools for diabetes screening, especially in developing countries. However, the semi-lab model outperformed the non-lab model and NCDRS prediction systems and might be worth being adopted as decision support in diabetes screening in China.
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| 3. |
- Niemi, MEK, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 4. |
- Wang, Tianyu, et al.
(författare)
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Data-efficient multimodal human action recognition for proactive human–robot collaborative assembly: A cross-domain few-shot learning approach
- 2024
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Ingår i: Robotics and Computer-Integrated Manufacturing. - : Elsevier BV. - 0736-5845 .- 1879-2537. ; 89
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Tidskriftsartikel (refereegranskat)abstract
- With the recent vision of Industry 5.0, the cognitive capability of robots plays a crucial role in advancing proactive human–robot collaborative assembly. As a basis of the mutual empathy, the understanding of a human operator's intention has been primarily studied through the technique of human action recognition. Existing deep learning-based methods demonstrate remarkable efficacy in handling information-rich data such as physiological measurements and videos, where the latter category represents a more natural perception input. However, deploying these methods in new unseen assembly scenarios requires first collecting abundant case-specific data. This leads to significant manual effort and poor flexibility. To deal with the issue, this paper proposes a novel cross-domain few-shot learning method for data-efficient multimodal human action recognition. A hierarchical data fusion mechanism is designed to jointly leverage the skeletons, RGB images and depth maps with complementary information. Then a temporal CrossTransformer is developed to enable the action recognition with very limited amount of data. Lightweight domain adapters are integrated to further improve the generalization with fast finetuning. Extensive experiments on a real car engine assembly case show the superior performance of proposed method over state-of-the-art regarding both accuracy and finetuning efficiency. Real-time demonstrations and ablation study further indicate the potential of early recognition, which is beneficial for the robot procedures generation in practical applications. In summary, this paper contributes to the rarely explored realm of data-efficient human action recognition for proactive human–robot collaboration.
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| 5. |
- Ding, Haoming, et al.
(författare)
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Progress in Structural Tailoring and Properties of Ternary Layered Ceramics
- 2023
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Ingår i: Journal of Inorganic Materials. - : SCIENCE PRESS. - 1000-324X. ; 38:8, s. 845-884
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Forskningsöversikt (refereegranskat)abstract
- MAX/MAB phases are a series of non-van der Waals ternary layered ceramic materials with a hexagonal structure, rich in elemental composition and crystal structure, and embody physical properties of both ceramics and metals. They exhibit great potential for applications in extreme environments such as high temperature, strong corrosion, and irradiation. In recent years, two-dimensional (2D) materials derived from the MAX/MAB phase (MXene and MBene) have attracted enormous interest in the fields of materials physics and materials chemistry and become a new 2D van der Waals material after graphene and transition metal dichalcogenides. Therefore, structural modulation of MAX/MAB phase materials is essential for understanding the intrinsic properties of this broad class of layered ceramics and for investigating the functional properties of their derived structures. In this paper, we summarize new developments in MAX/MAB phases in recent years in terms of structural modulation, theoretical calculation, and fundamental application research and provide an outlook on the key challenges and prospects for the future development of these layered materials.
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| 6. |
- Li, Youbing, et al.
(författare)
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A-site alloying-guided universal design of noble metal-based MAX phases
- 2024
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Ingår i: Matter. - : Cell Press. - 2590-2393 .- 2590-2385. ; 7:2, s. 523-538
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Tidskriftsartikel (refereegranskat)abstract
- Mn+1AXn (MAX) phases have attracted significant attention due to their structural diversity and potential applications. Designing MAX phases with single-atom-thick A layers featuring 4d/5d-orbital electronic elements is interesting work. Here, we present a comprehensive report on noble metal-based M2(A1-xA′x)C (M = V, Ti, Nb; A = Al, Sn, In, Ga, Ge; A′ = Ru, Rh, Pd, Ir, Pt, Au and combinations thereof; 0 < x ≤ 0.4) phases featuring A sublayers of 4d/5d-orbital electronic elements through an A-site alloying strategy. The chemical composition of MAX phases can be adjusted by selecting different M- and A-site elements, with morphology tailored by distinct C sources. Furthermore, the V2(Sn0.8Pt0.2)C (15.7 wt % Pt) catalyst showed better performance for hydrogen evolution reaction compared to the commercial Pt/C (20 wt % Pt) electrode. This study highlights the prospects of A-site alloying for the design of novel MAX phases with unique properties and promising applications in electrocatalysis and beyond.
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| 7. |
- Li, Youbing, et al.
(författare)
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Single-Atom-Thick Active Layers Realized in Nanolaminated Ti-3(AlxCu1-x)C-2 and Its Artificial Enzyme Behavior
- 2019
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Ingår i: ACS Nano. - : AMER CHEMICAL SOC. - 1936-0851 .- 1936-086X. ; 13:8, s. 9198-9205
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Tidskriftsartikel (refereegranskat)abstract
- A Ti-3(AlxCu1-x)C-2 phase with Cu atoms with a degree of ordering in the A plane is synthesized through the A site replacement reaction in CuCl2 molten salt. The weakly bonded single -atom -thick Cu layers in a Ti-3(AlxCu1-x)C-2 MAX phase provide actives sites for catalysis chemistry. As -synthesized Ti-3(AlxCu1-x)C-2 presents unusual peroxidase-like catalytic activity similar to that of natural enzymes. A fabricated Ti-3(AlxCu1-x)C-2/chitosan/glassy carbon electrode biosensor prototype also exhibits a low detection limit in the electrochemical sensing of H2O2. These results have broad implications for property tailoring in a nanolaminated MAX phase by replacing the A site with late transition elements.
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| 8. |
- Wang, Le, et al.
(författare)
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A Hybrid Data-Driven Soft Sensor Framework for Torque Estimation
- 2023
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Ingår i: IEEE Sensors Journal. - : Institute of Electrical and Electronics Engineers (IEEE). - 1530-437X .- 1558-1748. ; 23:20, s. 24993-25004
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Tidskriftsartikel (refereegranskat)abstract
- Efficient torque estimation plays an important role for the real-time durability analysis of vehicle components. It is desired to replace expensive torque sensors by applying soft sensor methods to accurately estimate the torque signals. However, due to the occurrence of the dead-zone phenomenon in torque signals on part-time four-wheel-drive (PT-4WD) vehicles when accelerating or braking (BK), normal linear identification methods, like multiple-input single-output finite impulse response (MISO-FIR), may not be directly applicable for torque estimation. A novel data-driven soft sensor method including an estimator and a classifier is proposed in this article. First, a logistic regression (LR) based classifier uses the low sampling-frequency input data to detect the time periods when the dead-zone phenomenon happens. Then, an estimator, using MISO-FIR, is applied to estimate the target output based on the other known sensor signals over time periods detected by the classifier. As a result, a complicated nonlinear system identification problem has been solved with the proposed bounded-input bounded-output and explainable method. The proposed hybrid method is validated on multiple experiments with historical datasets where the dead-zone phenomenon occurs. Extensive experiments demonstrate that the proposed method outperforms multiple baseline methods in the comparison study, achieving a smaller normalized mean squared error (NMSE) and a larger goodness of fit (FIT) with a considerably lower computational cost.
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| 9. |
- Chaffey, Geraint, et al.
(författare)
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Demonstration of Multi-vendor Protection Systems for Multiterminal VSC-HVDC Networks
- 2021
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Ingår i: 2021 IEEE Madrid PowerTech, PowerTech 2021 - Conference Proceedings. - : Institute of Electrical and Electronics Engineers (IEEE).
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Konferensbidrag (refereegranskat)abstract
- This paper outlines the demonstration of partially selective and fully selective HVDC protection systems using a simulated industrial case study HVDC network, hardware HVDC protection IED prototypes, and simulated HVDC circuit breaker models. A summary of results are presented demonstrating the performance of the protection IEDs and indicating successful operation of the overall HVDC protection system according to system-level indicators. The presented results are intended to increase confidence that HVDC protection systems for multivendor HVDC networks are near ready for full-scale industrial implementation.
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| 10. |
- Chaffey, Geraint, et al.
(författare)
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Design of backup protection for the DC interconnection of adjacent point-to-point HVDC systems
- 2022
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Ingår i: Proceedings 16th International Conference on Developments in Power System Protection, DPSP 2022. - : Institution of Engineering and Technology (IET). ; , s. 25-30
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In order to provide additional flexibility in future power systems, it could be beneficial to connect existing point-to-point highvoltage direct-current (HVDC) systems at the DC-side into a multiterminal network. Such a network would allow increased operational flexibility, continued operation in case of maintenance, and could reduce the end-to-end losses in the overall system. The protection of such a system, however, poses interesting challenges with constraints which differ slightly from typical HVDC grid protection studies. This paper focuses on the trade-offs surrounding the backup protection strategy following failure of a DC circuit breaker in the primary protection role. For this particular application, where a control retrofit should be avoided, the focus is on enabling quicker recovery rather than attempting to maintain continuous operation on a charged and healthy network. Therefore, the functional requirements on the backup switchgear are in some respects reduced compared to that required for primary protection. The benefits of reduced voltage switchgear for this backup protection application are therefore investigated.
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| 11. |
- Chaffey, Geraint, et al.
(författare)
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Requirements for functional testing of HVDC protection IEDs
- 2019
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Konferensbidrag (refereegranskat)abstract
- Development of Intelligent Electronic Devices (IED) for HVDC protection is underway, driven in part by the prospective demands of future multiterminal HVDC systems. There is, however, no consensus on how to test the functionality of an HVDC protection IED. Successful operation of a future multivendor HVDC protection system requires functional specifications and harmonised test procedures for protection system components, including the protection IED. This paper presents an introduction to functional testing methods for HVDC protection IEDs. Evaluating the protection algorithm characteristic using synthetic waveforms is first performed, i.e. ’functional type testing’. Given that test procedures are in part dependent on the protection algorithm, tests are developed and presented for several algorithms. The behaviour of the IED in a power system simulation is then examined during generalised yet representative fault transients, i.e. equivalent to ’dynamic validation type testing’ of AC protection algorithms. The combination of functional and dynamic validation type testing allows the generalised functionality of the IED to be evaluated - testing the algorithm, hardware and software implementation, and overall performance. To provide examples of test procedures, an open-source HVDC IED prototype is tested in a hardware-in-the-loop configuration using a real-time simulator. The operation and accuracy of the protection characteristics are first examined, before the IED performance under representative waveforms is determined. Through tests of several non-unit line protection algorithms, it is shown that, depending on the algorithm applied, the IED is dependable for simulated faults within the protection zone, and secure during external faults. Moreover,the test configurations and procedures required to evaluate the functionality and the criteria for success are developed.
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| 12. |
- Ding, Haoming, et al.
(författare)
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Synthesis of MAX phases Nb2CuC and Ti2(Al0.1Cu0.9)N by A-site replacement reaction in molten salts
- 2019
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Ingår i: Materials Research Letters. - : Taylor & Francis. - 2166-3831. ; 7:12, s. 510-516
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Tidskriftsartikel (refereegranskat)abstract
- New MAX phases Ti2(AlxCu1−x)N and Nb2CuC were synthesized by A-site replacement by reacting Ti2AlN and Nb2AlC, respectively, with CuCl2 or CuI molten salt. X-ray diffraction, scanning electron microscopy, and atomically resolved scanning transmission electron microscopy showed complete A-site replacement in Nb2AlC, which lead to the formation of Nb2CuC. However, the replacement of Al in Ti2AlN phase was only close to complete at Ti2(Al0.1Cu0.9)N. Density-functional theory calculations corroborated the structural stability of Nb2CuC and Ti2CuN phases. Moreover, the calculated cleavage energy in these Cu-containing MAX phases are weaker than in their Al-containing counterparts.The preparation of MAX phases Nb2CuC and Ti2(Al0.1Cu0.9)N were realized by A-site replacement in Ti2AlN and Nb2AlN, respectively.
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| 13. |
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| 14. |
- Hu, Yunhao, et al.
(författare)
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Cut-in Critical Level Prediction via Simulation Based Time-to-Collision Algorithm
- 2020
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Ingår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 643-650
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Konferensbidrag (refereegranskat)abstract
- Cut-in critical level prediction is of vital importance to Advanced Driving Assistance system (ADAS) to fulfil regional requirements and to increase safety. Time-to-Collision is the key component for critical levels of cut-in scenario. Hence, a new simulation based Time-to-Collision (TTC) calculation algorithm is firstly introduced in this paper. For the purpose of cut-in critical level prediction, the values of TTC in c.a 2000 cut-in cases are calculated, which are used to train a novel machine learning based cut-in critical level prediction method. The goal of ADAS functions development is to perform as a sophisticated driver, especially in dealing with risks. Thus, the correlation coefficient between ego vehicle deceleration and TTC could be used to evaluate the performance of different TTC calculation methods. In order to validate the superiority of simulation based TTC calculation algorithm, the Pearson correlation coefficient is calculated for the simulation based TTC and the TTC calculated by the traditional method, which are 0.7882 and 0.1357, respectively. Through enough valid regional cut-in samples trained prediction algorithm, TTC could be estimated accurately and effectively, i.e., the accuracy reaches 92%. To the best of the author's knowledge the simulation based TTC calculation method and the cut-in critical level prediction learning algorithm are new contributions in ADAS field.
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| 15. |
- Jahn, Ilka, et al.
(författare)
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Requirements for open specifications in multivendor HVDC protection systems
- 2020
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Konferensbidrag (refereegranskat)abstract
- Integrating multiterminal high-voltage direct-current (HVDC) connections into the existing alternating current (AC) power transmission system is a possible solution for transport of large amounts of renewable energy. Protection is considered a key enabler for multiterminal HVDC (MTDC) grids. Designing such a protection system is a challenge, in particular in a multivendor setup. Fault detection during transients might be required to achieve the stringent speed requirements for HVDC protection. This in turn requires knowledge about the expected system behaviour during faults and involves knowledge from all vendors supplying equipment in MTDC grid. Traditionally, HVDC projects are, however, supplied as turn-key solutions and the control and protection systems are the intellectual property of the vendors and not open for the HVDC end-users. This paper aims to provide a starting point on the discussion which information has to be shared between vendorsand HVDC end-users when designing MTDC grid protection. Simulations results show that missing information about certain aspects can lead to a failure of the protection system. A discussion on organization of the available information is added. Open specifications of the used equipment are useful to design safe and reliable MTDC grid protection.
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| 16. |
- Olson, Nathan D., et al.
(författare)
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precisionFDA Truth Challenge V2: Calling variants from short- and long-reads in difficult-to-map regions
- 2020
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The precisionFDA Truth Challenge V2 aimed to assess the state-of-the-art of variant calling in difficult-to-map regions and the Major Histocompatibility Complex (MHC). Starting with FASTQ files, 20 challenge participants applied their variant calling pipelines and submitted 64 variant callsets for one or more sequencing technologies (~35X Illumina, ~35X PacBio HiFi, and ~50X Oxford Nanopore Technologies). Submissions were evaluated following best practices for benchmarking small variants with the new GIAB benchmark sets and genome stratifications. Challenge submissions included a number of innovative methods for all three technologies, with graph-based and machine-learning methods scoring best for short-read and long-read datasets, respectively. New methods out-performed the 2016 Truth Challenge winners, and new machine-learning approaches combining multiple sequencing technologies performed particularly well. Recent developments in sequencing and variant calling have enabled benchmarking variants in challenging genomic regions, paving the way for the identification of previously unknown clinically relevant variants.
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| 17. |
- Olson, Nathan D., et al.
(författare)
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PrecisionFDA Truth Challenge V2: Calling variants from short and long reads in difficult-to-map regions
- 2022
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Ingår i: Cell Genomics. - : Elsevier BV. - 2666-979X. ; 2:5, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- The precisionFDA Truth Challenge V2 aimed to assess the state of the art of variant calling in challenging genomic regions. Starting with FASTQs, 20 challenge participants applied their variant-calling pipelines and submitted 64 variant call sets for one or more sequencing technologies (Illumina, PacBio HiFi, and Oxford Nanopore Technologies). Submissions were evaluated following best practices for benchmarking small variants with updated Genome in a Bottle benchmark sets and genome stratifications. Challenge submissions included numerous innovative methods, with graph-based and machine learning methods scoring best for short-read and long-read datasets, respectively. With machine learning approaches, combining multiple sequencing technologies performed particularly well. Recent developments in sequencing and variant calling have enabled benchmarking variants in challenging genomic regions, paving the way for the identification of previously unknown clinically relevant variants.
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| 18. |
- Wang, Gang, et al.
(författare)
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Spirometric phenotypes from early childhood to young adulthood : a Chronic Airway Disease Early Stratification study
- 2021
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Ingår i: ERJ Open Research. - : ERS Publications. - 2312-0541. ; 7:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: The prevalences of obstructive and restrictive spirometric phenotypes, and their relation to early-life risk factors from childhood to young adulthood remain poorly understood. The aim was to explore these phenotypes and associations with well-known respiratory risk factors across ages and populations in European cohorts.Methods: We studied 49334 participants from 14 population-based cohorts in different age groups (⩽10, >10–15, >15–20, >20–25 years, and overall, 5–25 years). The obstructive phenotype was defined as forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) z-score less than the lower limit of normal (LLN), whereas the restrictive phenotype was defined as FEV1/FVC z-score ⩾LLN, and FVC z-score Results: The prevalence of obstructive and restrictive phenotypes varied from 3.2–10.9% and 1.8–7.7%, respectively, without clear age trends. A diagnosis of asthma (adjusted odds ratio (aOR=2.55, 95% CI 2.14–3.04), preterm birth (aOR=1.84, 1.27–2.66), maternal smoking during pregnancy (aOR=1.16, 95% CI 1.01–1.35) and family history of asthma (aOR=1.44, 95% CI 1.25–1.66) were associated with a higher prevalence of obstructive, but not restrictive, phenotype across ages (5–25 years). A higher current body mass index (BMI was more often observed in those with the obstructive phenotype but less in those with the restrictive phenotype (aOR=1.05, 95% CI 1.03–1.06 and aOR=0.81, 95% CI 0.78–0.85, per kg·m−2 increase in BMI, respectively). Current smoking was associated with the obstructive phenotype in participants older than 10 years (aOR=1.24, 95% CI 1.05–1.46).Conclusion: Obstructive and restrictive phenotypes were found to be relatively prevalent during childhood, which supports the early origins concept. Several well-known respiratory risk factors were associated with the obstructive phenotype, whereas only low BMI was associated with the restrictive phenotype, suggesting different underlying pathobiology of these two phenotypes.
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| 19. |
- Wang, Juncheng, et al.
(författare)
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Preparation and in vitro evaluation of strontium-doped calcium silicate/gypsum bioactive bone cement
- 2014
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Ingår i: Biomedical Materials. - : IOP Publishing. - 1748-6041 .- 1748-605X. ; 9:4, s. 045002-
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Tidskriftsartikel (refereegranskat)abstract
- The combination of two or more bioactive components with different biodegradability could cooperatively improve the physicochemical and biological performances of the biomaterials. Here we explore the use of alpha-calcium sulfate hemihydrate (alpha-CSH) and calcium silicate with and without strontium doping (Sr-CSi, CSi) to fabricate new bioactive cements with appropriate biodegradability as bone implants. The cements were fabricated by adding different amounts (0-35 wt%) of Sr-CSi (or CSi) into the alpha-CSH-based pastes at a liquid-to-solid ratio of 0.4. The addition of Sr-CSi into alpha-CSH cements not only led to a pH rise in the immersion medium, but also changed the surface reactivity of cements, making them more bioactive and therefore promoting apatite mineralization in simulated body fluid (SBF). The impact of additives on long-term in vitro degradation was evaluated by soaking the cements in Tris buffer, SBF, and alpha-minimal essential medium (alpha-MEM) for a period of five weeks. An addition of 20% Sr-CSi to alpha-CSH cement retarded the weight loss of the samples to 36% (in Tris buffer), 43% (in SBF) and 54% (in alpha-MEM) as compared with the pure alpha-CSH cement. However, the addition of CSi resulted in a slightly faster degradation in comparison with Sr-CSi in these media. Finally, the in vitro cell-ion dissolution products interaction study using human fetal osteoblast cells demonstrated that the addition of Sr-CSi improved cell viability and proliferation. These results indicate that tailorable bioactivity and biodegradation behavior can be achieved in gypsum cement by adding Sr-CSi, and such biocements will be of benefit for enhancing bone defect repair.
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| 20. |
- Wang, Mian, et al.
(författare)
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Multi-vendor interoperability tests of IEDs for HVDC grid protection
- 2020
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Konferensbidrag (refereegranskat)abstract
- Future large scale HVDC systems must have components from different manufacturers, however, this will require multi-vendor interoperability. This paper studies multi-vendor interoperability of HVDC protection IEDs using hardware IED prototypes developed by industrial and academic partners. Multi-vendor interoperability tests are performed using real-time hardware-in-the-loop simulations based on open-access converter models configured to represent the proposed three-terminal design of an extension to an existing point-to-point HVDC system in the UK. In particular, this paper focuses on developing testing procedures for IEDs in a multi-vendor environment and identifying possible interoperability issues. Interoperability of two hardware IEDs is demonstrated during primary protection, IED failure backup protection and breaker failure backup protection. In each case, the protection scheme operates correctly and it is shown that, in the studied scenarios,the protection IEDs are interoperable.
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| 21. |
- Wang, Mian, et al.
(författare)
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Pre-standardisation of Interfaces between DC Circuit Breaker and Intelligent Electronic Device to Enable Multivendor Interoperability
- 2019
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Konferensbidrag (refereegranskat)abstract
- DC circuit breakers (DCCBs) are one of the key components to facilitate large meshed HVDC grids. Driven by the needs for achieving high speed, low loss and low cost, various DCCB technologies have been proposed for HVDC applications. Unlike AC circuit breakers (ACCBs), some DCCBs provide a variety of functions, such as proactive opening or fault current limiting (FCL), mainly attributed to the high controllability of the power electronic switches used in such DCCBs. To enable these functions, the intelligent electronic devices (IEDs) are expected to provide signals steering these functions in addition to a trip command. Interoperability between IEDs and DCCBs from different vendors is considered feasible, but expected to be more complex than their AC counterparts, due to the different functions provided by various DCCB technologies. It is therefore crucial to understand which of the functions are essential to fulfil the requirements imposed in HVDC grid protection, and to standardise the interfaces between the IEDs and DCCBs to achieve multivendor interoperability between IEDs and DCCBs provided by different vendors. This paper first classifies the DCCB functions into minimally required and auxiliary ones based on reviewing the existing literature. Then, standardised interfaces between the IEDs and DCCBs are proposed to enable both types of DCCB functions. An example of such IED is implemented in PSCAD/EMTDC to demonstrate that the proposed interfaces are adequate to enable both minimally required and auxiliary functions using a four-terminal test system. Auxiliary functions of hybrid DCCBs, such as proactive opening, fault current limiting, fast reclosing and reopening, breaker failure internal detection and repeated O-C-O operation are demonstrated by simulations.
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