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Standard Function Blocks for Flexible IED in IEC 61850-Based Substation Automation Lin Zhu, Student Member, IEEE, Dongyuan Shi, and Xianzhong Duan, Member, IEEE
Abstract—Flexible intelligent electronic devices (IEDs) are highly desirable to support free allocation of function to IED by means of software reconfiguration without any change of hardware. The application of generic hardware platforms and component-based software technology seems to be a good solution. Due to the advent of IEC 61850, generic hardware platforms with a standard communication interface can be used to implement different kinds of functions with high flexibility. The remaining challenge is the unified function model that specifies various software components with appropriate granularity and provides a framework to integrate them efficiently. This paper proposes the function-block (FB)-based function model for flexible IEDs. The standard FBs are established by combining the IEC 61850 model and the IEC 61499 model. The design of a simplified distance protection IED using standard FBs is described and investigated. The testing results of the prototype system in MATLAB/Simulink demonstrate the feasibility and flexibility of FB-based IEDs. Index Terms—Flexible IED, IEC 61499, IEC 61850, logical node, standard function blocks, substation automation.
Directory
IEC 61850 services for data access.
DO
Data object.
ECC
Execution control chart.
FB
Function block.
GAPC_FB
FB model of generic automatic process control.
GGIO_FB
FB model of generic process I/O.
GndPDIS(i)_FB
FB model of ground distance protection (zone I, II, or III).
GOOSE
Generic object-oriented substation events.
IED
Intelligent electronic device.
LD
Logical device.
LLN0
Logical node for logical device information.
LN
Logical node.
LPHD
Logical node for physical device information.
MMXU_FB
FB model of measurement.
MSQI_FB
FB model of sequence and imbalance.
PDIS_FB
FB model of distance protection.
PhPDIS(i)_FB
FB model of phase-to-phase distance protection (zone I, II, or III).
NOMENCLATURE ACSI
Abstract communication services interface.
ARCO
FB model of reactive power control.
ATCC
Automatic tap changer controller.
CDC
Common data class.
CFB
Compound function block.
CILD_FB
FB model of islanding.
CILO_FB
FB model of interlocking.
PTOC_FB
FB model of time over current protection.
CLSD_FB
FB model of load shedding.
PTRC_FB
FB model of trip condition.
CSWI_FB
FB model of the switch controller.
RCVA_FB
DA
Data attribute.
FB model of characteristic values algorithm.
DataSet
IEC 61850 services for a group of data objects and data attributes.
RFLT_FB
FB model of filter algorithm.
RPHS_FB
FB model of phase selection.
RPSB_FB
FB model of power swing detection/blocking.
RREC_FB
FB model of autoreclosing.
RSTR_FB
FB model of startup criterion.
RSYN_FB
FB model of synchronism-check or synchronizing.
SAS
Substation automation system.
SAV
Sampled analog value.
Manuscript received May 21, 2010; revised September 20, 2010; accepted October 23, 2010. Date of publication December 23, 2010; date of current version March 25, 2011. This work was supported in part by the National Science Youth Foundation of China under Grant 50907024 and in part by the Project of the National Key Technology R&D program of China under Grant 2008BAA13B00. Paper no. TPWRD-00379-2010. The authors are with the College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. (e-mail:
[email protected]). Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TPWRD.2010.2091154
0885-8977/$26.00 © 2010 IEEE
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SGCB
Setting group control block, the IEC 61850 services for settings.
SIFB
Service interface function block.
ZerPTOC(i)_FB FB model of zero-sequence over current protection (zone I or II).
I. INTRODUCTION URING the last decades, electromechanical devices in substation automation system (SAS) have been replaced by intelligent electronic devices (IEDs). Most functions including protection and control are now performed by IEDs [1]. As more advanced and powerful hardware platforms become available, there is growing interest not only in the integration of more functions into fewer IEDs for low cost, but also in flexible IEDs that support free allocation of functions to devices for short project duration [2], [3]. A flexible IED is expected to permit different kinds of function integration or distribution by means of software reconfiguration without any change of hardware. However, current IEDs generally consist of vendor-specific hardware and hardware-dependent software with limited flexibility. Due to the cable connection to sensors and circuit breakers (CBs), the hardware platforms of IEDs have to provide complex analog input/output (I/O) interfaces to map the electrical signals for designated functions. It may be necessary to add new analog I/O interfaces when adding new functions. On the other hand, the hardware-dependent software cannot be reused and integrated on different hardware platforms for other new applications. In addition, the software system is still implemented with little software engineering methodology, which makes it inconvenient to develop and maintain IEDs, especially to add, remove, or replace functions. The application of generic hardware platforms and component-based software technology seems to be a good solution for flexible IEDs. With the rapid development of IEC 61850-based substation automation, traditional point-to-point cables are replaced by a process bus-based shared communication network [4], [5]. Since standard communication removes the differences of various dedicated hardware platforms, generic hardware platforms with a standard network interface can be used to implement protection, control, metering, recording, as well as any combination. If the function assigned to an IED changes, it is necessary to modify several communication parameters to collect the required information rather than add or remove many analog I/O interfaces. Meanwhile, the application of generic hardware platforms separates software from hardware and makes it possible to construct a flexible and hardware-independent software system [6], [7]. For example, component-based software technology will be adopted to encapsulate mature algorithms into standard and reusable software components [8], [9]. A developer is likely to select several software components containing protective relay algorithms, control algorithms, or communication services, set their parameters, and then integrate them with software tools to implement an IED with high flexibility.
D
Since generic hardware platforms are available in the worldwide commercial market, the remaining challenge of flexible IEDs is the unified function model, which specifies various software components with appropriate granularity and provides a framework to construct flexible software system efficiently. Although the IEC 61850 standard defines the unified information model for IEDs and SAS, it lacks specification of detailed function algorithms and function-related data objects [10]. In fact, the IEC 61850 model describes the data that need to be exchanged with other IEDs for communication purposes; thus, it is not sufficient to describe the unified function model of IEDs. The second edition of the IEC 61850 standard is under revision, but current modification and extension still focus on the information model [11]. Another international standard IEC 61499 providing a generic function model based on the function block (FB) for the control device and distributed control system may make up this disadvantage. An FB is considered as an abstract of a software component by encapsulating algorithms, state transitions, and well-defined event/data interfaces [12]. The unified function model of IEDs can be established based on the concept of FB, while the IEC 61850 model must be preserved for communication purposes. Therefore, it makes significant sense to combine the two models to construct standard FBs for flexible IEDs [13], [14]. The aim of this paper is to provide a standard FBs-based function model for flexible IEDs. The modeling approach and application of standard FBs are also introduced. The remainder of this paper is organized as follows. Section II summarizes the main characteristics of the IEC 61850 model and the IEC 61499 model. The modeling approach of standard FBs is presented in Section III. Section IV demonstrates the application of standard FBs, followed by a description of a simplified distance protection IED based on FBs. In Section V, the prototype system is implemented in PSCAD/EMTDC and MATLAB/Simulink to validate the feasibility and flexibility of FBs-based IEDs. Finally, Section VI concludes this paper. II. CHARACTERISTICS OF THE IEC 61850 AND THE IEC 61499 MODELS A. Characteristics of the IEC 61850 Model IEC 61850 is a popular international standard for communication networks and systems in substations. It provides abundant information model for IEDs and SAS. The hierarchical information model is shown in Fig. 1. Logical node (LN) is an important concept in the IEC 61850, which represents the “smallest part of a function that exchanges data” [10]. Each LN consists of mandatory, conditional, or optional data objects (DOs) containing corresponding data attributes (DAs). LNs can be grouped into a logical device (LD), while LDs can be grouped into a server representing the communication visible behaviors of an IED. Furthermore, the standard also offers a series of communication services to access the information model and exchange data (e.g., directory, data access, event report, and log). The interoperability among IEDs from different manufacturers is achieved if they adopt the standard information model and communication services.
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Fig. 1. Information model of the IEC 61850.
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The FB model is the elementary model of the standard. An FB is a functional unit consisting of a set of event inputs/outputs, a set of data inputs/outputs, and several encapsulated algorithms. An FB receives event/data from input interfaces, processes them by algorithms, and produces event/data outputs. The causal relationships among event inputs, event outputs, and execution of algorithms are specified by an execution control chart (ECC), which is similar to a state machine. Basic FBs are generally integrated into a composite FB (CFB) to represent complex functions. Besides the control algorithms, communication protocols can also be encapsulated into an FB. The protocols of communication services for data exchange are usually modeled by service-interface FBs (SIFBs). In the IEC 61499 architecture, other models can be constructed based on FBs. For example, the application model is built by an FB network, whose nodes are basic FBs, CFBs, or SIFBs, and whose branches are event/data connections. The resource model is comprised of one or more “local application” and communication interfaces. The device model contains one or more interfaces (communication interface or process interface) and one or more resources. The FB-based architecture of the control device enables a modularization design approach and makes the development process more simplified and efficient. Nevertheless, since the IEC 61499 model is a conceptual reference model for generic purposes, it is necessary to establish a derived class model of FBs for a particular application from an object-oriented point of view. C. Combination of the Two Models The IEC 61850 model lacks specification of detailed functions and function-related data, but it should be reserved for communication. The IEC 61499 model is designed for general purpose and, thus, it needs some modification before being adopted in particular applications. Therefore, it makes significant sense to combine the two models to buildup standard FBs for flexible IEDs. In this way, software system of IEDs can be viewed as an integration of standard and reusable software components, such as protective relay algorithms, control algorithms, and communication services. The FB-based architecture is also convenient to design and develop IEDs with high flexibility in a cost-effective way.
Fig. 2. Function model of the IEC 61499.
III. MODELING OF STANDARD FBS A. Basic Modeling Principles
As the IEC 61850 model is totally utilized for communication purposes, it only describes the data that need to be exchanged with other IEDs. The model is a partial abstract of function entities without the specification of detailed functions and function-related data. Therefore, the IEC 61850 model is not sufficient to represent the function model of IEDs. B. Characteristics of the IEC 61499 Model The IEC 61499 standard defines a generic function model based on FBs for distributed control and automation systems. The four main models (FB, application, resource, and device) of the standard are shown in Fig. 2.
Since both standards adopt an object-oriented approach, the model architectures are hierarchical and similar. It is not difficult to establish a mapping between the IEC 61850 model and the IEC 61499 model. As shown in Table I, DOs are represented by basic FBs, while LNs are represented by CFBs. LDs and servers are mapped into resources and devices, respectively. In addition, abstract communication services interfaces (ACSI) are mapped into SIFBs. The authors of [14] propose direct mapping from an LN to CFB to implement a decentralized power-supply restoration system consisting of several devices. However, some indispensable functions not defined in the IEC 61850, and the ECC of
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TABLE I OBJECT MODEL MAPPING BETWEEN IEC 61850 AND IEC 61499
FBs are not considered, which are important for the design and implementation of an individual IED. Hence, the modeling of standard FBs in this paper will focus on three aspects besides inheritance of all DOs of an LN: 1) definition of detailed function algorithms: 2) execution logic of the algorithms (ECC); and 3) the specification of function-related event/data interfaces. In the following subsections, we propose different methods for modeling standard FBs: 1) extend existing LNs for functions mentioned in the IEC 61850; 2) create new FBs for functions not mentioned in the IEC 61850: and 3) encapsulate the communication services into SIFBs. B. Extension of Existing LNs For the functions that have been mentioned in the IEC 61850 standard, corresponding FBs can be modeled by means of extension of existing LNs [15]. First of all, the DOs and DAs contained in LNs must be inherited. Second, several function algorithms (e.g. protective relay algorithms and control algorithms) should be specified and encapsulated. Since existing DOs may not include the data inputs or outputs of the function algorithms, several DOs should be created and added for a complete event/data flow. Finally, the sequence of algorithm invocations is declared in an ECC. The name of an FB inherits that of the corresponding LN and is distinguished with the postfix “_FB.” The FB model of distance protection (PDIS_FB) is illustrated in Fig. 3(a). Common LN information, settings, and status information are inherited from the PDIS class in the IEC 61850. ACD, SPS, INS, etc. are CDCs that represent the data type of the DOs. Characteristic values (voltage and current value of each phase) are extended DOs as data inputs feeding into different algorithms, including phase-to-ground and phase-to-phase distance protection. The WITH qualifier (graphical sign “ ”) specifies an association among the input events and data (or output events and data). Common LN information, settings. and status information (Str) are loaded with initial values if the initialization event (INIT) occurs. When the FB receives an execution event (EX1 or EX2), it begins to deal with the characteristic value to make a trip decision with the PhtoGnd or PhtoPh algorithm. If the PDIS_FB decides to operate, the data output Op is produced with the event outputs EX1O or EX2O. Fig. 3(b) shows the ECC describing the relationship between event inputs/outputs and algorithm invocations. The FB model of every existing LN can be established in a similar way.
Fig. 3. Modeling of FBs by extending existing LNs. (a) PDIS_FB. (b) ECC.
C. Creation of New FBs Some indispensable functions, such as startup criterion and digital signal processing, are important for substation IEDs, but there are no corresponding LNs defined in the IEC 61850. Therefore, several new FBs and associated DOs may be created to represent these functions. Examples of these FBs are RSTR_FB (startup criterion), RFLT_FB (filter algorithm), RCVA_FB (characteristic values algorithm), RPHS_FB (phase selection), CLSD_FB (load shedding), and CILD_FB (islanding). Fig. 4(a) shows the RSTR_FB as an example. The FB deals with the sampled valves with different startup criterion algorithms (using mutational value or steady value) to decide whether to generate a startup signal. When the FB receives , , and the INIT event, the startup settings (e.g. ) are loaded with initial values. The execution sequence is controlled by the ECC shown in Fig. 4(b). D. Modeling of Communication Services There are two kinds of communication services in the IEC 61850 standard: one is Publisher-Subscriber (e.g., sampled analog value (SAV) and generic object oriented substation events (GOOSE), and the other is Server-Client (e.g., directory, report, and file transfer [16]). Both of them are mapped into SIFBs. Generally, a couple of FBs are needed to represent the sender and the receiver, respectively.
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Fig. 4. Creation of new FBs. (a) RSTR_FB. (b) ECC.
Setting Group Control Block (SGCB) RESPONDE is illustrated in Fig. 5(a) as an example and the SGCB REQUEST that does not appear in Server IEDs is omitted. Six kinds of communication services are offered by this FB: SelectActiveSG, SelectEditSG, SetSGvalues, GetSGvalues, ComfirmEditSGvalues, and GetSGCBvalues. When the FB receives a request ), corresponding communication serevent (REQ1, REQ2 vices are performed. The execution sequence is controlled by the ECC shown in Fig. 5(b). With the aforementioned modeling methods, the standard FB library can be built for flexible IEDs and part of the library is shown in Table II ( : new FBs created in this paper). The standard FBs are still a class model from the object-oriented point of view. It is necessary to create their instances for flexible IEDs in practical applications. IV. FLEXIBLE IED BASED ON STANDARD FBS Based on generic hardware platforms and standard FBs, a software system of IEDs can be viewed as an integration of reusable software components with high flexibility. The design and development of an IED is a stepwise but simple process with the following steps: Step 1) Decompose the required application function to a degree of granularity of the existing FBs. Step 2) Select corresponding FBs from the standard FB library for all the decomposed subfunctions, then
Fig. 5. SIFBs of server-client service. (a) SGCB RESPONDE. (b) ECC.
create instances of the selected FBs, set their parameters, and connect these FBs with data flow and event flow. Step 3) Validate the whole IED model to avoid errors. For example, check whether all of the DOs of the corresponding LN model are contained in the FB instance, and whether the FBs are connected with complete data flow and event flow. Step 4) Integrate physical components to IEDs and perform comprehensive testing. As an example, the design of a simplified distance protection IED using standard FBs is given. Fig. 6 shows the FB architecture of the IED. The IED consists of three main modules: 1)
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Fig. 6. FB architecture of a simplified distance protection IED with reclosure function.
TABLE II STANDARD FBS LIBRARY
protection and control; 2) communication services for station bus; and 3) communication services for the process bus. In the module of communication services for the process bus, SAV SUBSCRIBE and GOOSE SUBSCRIBE are designed to capture sampled values and status information for the IED, respectively. GOOSE PUBLISH is expected to provide communication services for the publication of trip and reclosure messages.
Since distance protection (phase-to-ground and phase-tophase) and zero-sequence overcurrent protection are multizone relays, each zone should be represented as an individual FB. As shown in Fig. 6, GndPDIS1_FB, GndPDIS2_FB, GndPDIS3_FB (three-stage phase-to-ground distance protections), PhPDIS1_FB, PhPDIS2_FB, PhPDIS3_FB (three-stage phase-to-phase distance protections), as well as ZerPTOC1_FB and ZerPTOC2_FB (two-stage zero-sequence overcurrent protections) are configured in the main function module. When the RSTR_FB deduces power system is in a real fault condition, sampled values are imported into different protection FBs after processing in RFLT_FB, RCVA_FB, and RPHS_FB. PTRC_FB is designed to combine the output data of protection FBs and then transmit a single-phase or triphase trip signal via GOOSE PUBLISH. RSYN_FB and RREC_FB are used to monitor the status of the CB from GOOSE SUBSCRIBE, check synchronization and send reclosure command via GOOSE PUBLISH. Directory RESPONDE, Dataset RESPONDE, and SGCB RESPONDE, etc., are applied to provide communication services for the station bus. All of the existing DOs are input data of directory RESPONDE (the DOs of GndPDIS1_FB are illustrated in Fig. 6), while the extended DOs and LNs are invisible in the IEC 61850 communication services. System LNs (LPHD and LLN0), without any function, are also included in the IED as indicators to communication services. Setting
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Fig. 7. Power system model used for the function test of protection IED.
TABLE III RELATED PARAMETERS OF THE POWER SYSTEM MODEL
values of different protection FBs are gathered as input data of DataSet RESPONDE and SGCB RESPONDE. V. PROTOTYPE SYSTEM AND TESTING A. Prototype System Implementation The prototype system is implemented in the MATLAB/ Simulink environment to demonstrate the feasibility and flexibility of FB-based distance protection IED. Particularly, SIFBs providing communication services are represented by S-Function blocks that encapsulate the source code of the MMS-EASE Lite software package. The software package encapsulates all of the network protocols referred to in the IEC 61850 and offers a C language application program interface for the Manufacturing Message Specification protocol [17]. The software packet is now widely applied when implementing IEC 61850-based IEDs. Transient data for protection and control function testing come from a two-machine system modeled in PSCAD/EMTDC. The power system model used for distance protection IED testing is shown in Fig. 7, and the related parameters are given in Table III [18]. The illustrated IED is not modeled in PSCAD/EMTDC since it is more convenient to integrate MMS-EASE Lite source code in MATLAB/Simulink than in PSCAD/EMTDC. B. Function Testing Various cases, such as different fault types, fault locations, and inception angles have been considered to examine the performance of protection and reclosure functions. Fig. 8 shows test results in the occurrence of an instantaneous grounding fault on Phase A. The fault occurs on 0.098 s and is isolated on 0.138 s. After checking the voltage of the two ends, RREC_FB sends GOOSE a message to reclose the CB on 0.954 s. Fig. 8(a) shows the current waveform of faulting phase A. The tripping signal of GndPDIS1_FB and the reclosure signal of RREC_FB are shown in Fig. 8(b) and (c), respectively. Test results of different cases
Fig. 8. Function test of the illustrated IED. (a) Current waveforms of Phase A in the occurrence of the instantaneous grounding fault on Phase A. (b) Tripping signal. (c) Reclosure signal.
TABLE IV TEST RESULTS OF DIFFERENT CASES
are given in Table IV. Through the simple function testing, the correctness of the proposed function model is demonstrated. C. Communication Services Testing The IEDScout software package is applied as an IEC 61850 client to connect the IED and perform communication services testing [19]. Fig. 9 shows part results of Directory service and GetSGValues service. The IED server consists of two LDs (E1Q1SB1CTRL and E1Q1SB1PROT) containing several LNs. The tree-structure data model is definitely shown by the Directory service.
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Fig. 9. Communication services testing of the illustrated IED.
GetSGValues service is designed to read values of the setting group. In the prototype system, settings are also grouped into a dataset. Thus, the result of GetSGValues service is equal to that of GetDateSetValues service reading the values of the correspondingdataset.AsshowninFig.9,theDataSetE1Q1SB1PROT/ LLN0.RelaySet describes the settings of all protection FBs, while the DataSet E1Q1SB1CTRL/LLN0.AutoCtrl describes the settings of synchronization check and reclosure. D. Flexible Function Extension Based on the modulated FB architecture, the existing FBs and software components do not need to be re-implemented when application requirements change. It is only necessary to add some new FBs and rearrange the connections between the existing FBs and added FBs. An example of adding Power Swing Blocking FB (RPSB_FB) will be shown. When the power system is in swing condition, slow periodic changing of measured impedance may result in tripping of the distance protection. RPSB_FB is used to block the output of protection FBs by checking the changing rate of measured impedance. For convenience, the instances of RPSB_FB should have the same instance numbers, such as the GndPDIS_FB and PhPDIS_FB per zone. As shown in Fig. 10, when the power system is swinging, the phase angle between the two-end machines and the voltage waveform of each phase are periodic changing. The measured impedance is also periodic changing and is sometimes located in the operation zone of PhPDIS2_FB and, thus, the distance protection is prone to misoperate. However, due to the existence of PhRPSB2_FB, Blk (output data of
PhRPSB2_FB) indicates that the power system is in swing condition and the misoperation is prevented. E. Discussion and Future Work The use of FBs for designing substation IEDs has many obvious and potential benefits. Perhaps the simplest but most important one is that the same IED is applicable for different function installations by means of software reconfiguration. It is also feasible to add, remove, and replace some functions of an IED on service when application requirements change. Another significant advantage is simplicity of design and development since it is possible to construct a software system with existing reusable software components. Modularization design and visual programming can be adopted to further expedite the development process. In addition, the reliability of the software system is also guaranteed when using software components containing mature algorithms. However, in order to implement IEDs using standard FBs, several software tools for modeling, integration, verification, and testing would be highly desirable. First of all, the modeling tool should include the complete FB library and enable the developer to build various data types, function block types, resource types, device types, and system configurations. Second, the integration and verification tools allow developers to connect selected FBs with event/data flows and configure their parameters. The whole model is validated to avoid latent error before the generation of source code. Finally, with the testing tools, the software system can be simulated and its performance can be assessed before IED implementation.
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VI. CONCLUSION The application of generic hardware platforms and component-based software technology has the potential to enhance the flexibility of substation IEDs. We propose the FB-based function model to construct a flexible software system for IEDs in a cost-effective way. The standard FBs are established with the extension of the IEC 61850 information model using the concept of the IEC 61499. The model enables an IED to not only integrate reusable software components to perform customized functions but also interoperate with other IEDs. Considerable merits of the proposed function model have been discussed in this paper. The prototype system in MATLAB/Simulink demonstrates the feasibility and flexibility of FB-based IEDs. Our future research work will focus on a complete standard FB library, experiment on a physical IED, and necessary software tools for flexible IED design and implementation. ACKNOWLEDGMENT The authors would like to thank the reviewers for their constructive comments. They would also like to thank Zhongyuan Huadian Science and Technology Co. Ltd. for the valuable software tools and references. REFERENCES
Fig. 10. Swing blocking. (a) Voltage waveform of phase A when the power system swings. (b) Measured impedance and operation zone. (c) Tripping signal. (d) Blocking signals.
Since the main content of this paper is the function model based on the IEC 61850 and IEC 61499, we investigate whether the model is able to represent functions of IEDs and support the IEC 61850 communication standard through the comparatively simple experiment. Although the example cases in the experiment may be sufficient to demonstrate the correctness of the proposed function model, the experiment should still be further improved. Our future research work will focus on three aspects: 1) construct a complete standard FB library for all IED subfunctions, especially for the actual subfunctions—those that are insufficient or not mentioned in the IEC 61850 (e.g., IED self-check, alarm, and human-machine interface); 2) implement a physical IED using the proposed FB-based design methodology to verify its feasibility in practical engineering, especially code efficiency and possible impacts on protection performances; and 3) necessary software tools for flexible IEDs design and implementation.
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IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 26, NO. 2, APRIL 2011
[16] Communication Networks and Systems in Substations-Part 7-2: Basic Communication Structure for Substation and Feeder Equipment-Abstract Communication Service Interfaces, IEC 61850-7-2, 2004, 1st ed. [17] “MMS-EASE Lite Reference Manual” SISCO. [Online]. Available: http://www.sisconet.com [18] X. Lin, P. Liu, and F. Hu, “Complete power system oscillation simulation for relay protection research,” (in Chinese) Autom. Elect. Power Syst., vol. 27, no. 22, pp. 56–59, Nov. 2003. [19] “IEDScout Demo” OMICRON. [Online]. Available: https://www.omicron.at/en/content/iedscout/download-iedscout/
Lin Zhu (S’07) was born in Anhui, China, in 1982. He received the B.S. degree from Huazhong University of Science and Technology (HUST), Wuhan, China, in 2005, where he is currently pursuing the Ph.D. degree in the College of Electrical and Electronic Engineering. Currently, he is attending a continuous academic project that involves postgraduate and doctoral study at HUST. His main research interests include industrial Ethernet, substation automation systems, networked control systems, and its application to the power system.
Dongyuan Shi was born in Hunan, China, in 1974. He received the B.S and Ph.D degrees from Huazhong University of Science and Technology (HUST), China, in 1996 and 2002, respectively. Dr. Shi is an Associate Professor in the College of Electrical and Electronic Engineering at HUST. His preference includes power system analysis and application of IT in power systems.
Xianzhong Duan (M’03) was born in Hunan, China, in 1966. He received the B.S. and Ph.D. degrees from Huazhong University of Science and Technology (HUST), Wuhan, China, in 1987 and 1992, respectively. Currently, he is a Full Professor in the College of Electrical and Electronic Engineering at HUST. His preference includes power system analysis and planning, voltage stability, flexible ac transmission systems, and the application of IT in power systems.
