Study Of Wide Area Fault Component Identification Algorithm And Its Communication Technology

Most conventional backup protections are designed to cover several components in a non-unit mode. Because of this principle, the mal-operation of backup protection has been identified as one of the contributing causes for cascading failures in power systems. Moreover, the operation of conventional backup protection relies on local data to protect equipments and commonly fails to consider the system security. However, WABP provides an alternative way to resolve those problems and attracts a lot of scholars’ attention.Firstly, a concept of superimposed impedance based on fault components is proposed with consideration of line distribution parameters. Based on this concept, this dissertation presents a fault component identification alrorithm based on superimposed impedance magnitude comparison. The algorithm’s operation characteristics are thoroughly analysed considering the impact of line length and source to line impedance ratio. The protection scheme uses operation of distance protection to start the fault information transmission and determine a collection of fault affected area. By searching the components in the collection, the algorithm can identify the faulty element.Secondly, an integrated control and protection scheme is presented to achieve wide area protection function with utilization of information from local and remote point. The synchrophasor client and server software are designed and realized according to IEEE C37.118 protocol. The synchrophasor communication model is given complied with IEC 61850-90-5 protocols. Next, the mapping of synchrophasor message to OSI protocol stack layer is studied according IEC 61850-90-5.Thirdly, it has significant meaning to verify the correctness and validity of information modeling in product development. After the function analysis at system level, the information model is deployed by a method from the top level. Meantime, the data structure is the basis to classify the function of validation testing tool. Using Excel and VBA as development platform, the operation state of the test object is preseted by programming. The values of data attributes are read via DDE mechanism through third-party MMS software. The readed values and expected values are compared to evaluate the validity and the correctness of the model data. Next, the test results are exported to the Excel object. The application of the validatioin tool shows that the test results are repeatable to verify the model’s comprehension.Fourthly, many protection devices support IEC 61850 to achieve seamless information exchange. Therefore, it is important to test and evaluate the performance of this kind of devices. The substation communication network is configured to ensure system redundant. A simple bus protection scheme has been realized through allocation of logic function from multiple devices. The test and evaluation work are performed based on RTDS simulation lab environment.