ABB RET670 Product Manual

Also see for RELION RET670: Operator's manual Commissioning manual Product guide Installation manual Commissioning manual

Contents

ABB RET670 Product Manual Manual pdf 15 page image

7. Secondary system supervisionFuse failure supervision SDDRFUFThe aim of the fuse failure supervision function (SDDRFUF) isto block voltage measuring functions at failures in thesecondary circuits between the voltage transformer and theIED in order to avoid unwanted operations that otherwisemight occur.The fuse failure supervision function basically has threedifferent algorithms, negative sequence and zero sequencebased algorithms and an additional delta voltage and deltacurrent algorithm.The negative sequence detection algorithm is recommendedfor IEDs used in isolated or high-impedance earthednetworks. It is based on the negative-sequence measuringquantities, a high value of voltage 3U2 without the presenceof the negative-sequence current 3I2.The zero sequence detection algorithm is recommended forIEDs used in directly or low impedance earthed networks. It isbased on the zero sequence measuring quantities, a highvalue of voltage 3U0 without the presence of the residualcurrent 3I0.For better adaptation to system requirements, an operationmode setting has been introduced which makes it possible toselect the operating conditions for negative sequence andzero sequence based function. The selection of differentoperation modes makes it possible to choose differentinteraction possibilities between the negative sequence andzero sequence based algorithm.A criterion based on delta current and delta voltagemeasurements can be added to the fuse failure supervisionfunction in order to detect a three phase fuse failure, which inpractice is more associated with voltage transformerswitching during station operations.8. ControlSynchrocheck, energizing check, and synchronizing SESRSYNThe Synchronizing function allows closing of asynchronousnetworks at the correct moment including the breaker closingtime, which improves the network stability.Synchrocheck, energizing check, and synchronizing(SESRSYN) function checks that the voltages on both sides ofthe circuit breaker are in synchronism, or with at least oneside dead to ensure that closing can be done safely.SESRSYN function includes a built-in voltage selectionscheme for double bus and 1½ breaker or ring busbararrangements.Manual closing as well as automatic reclosing can bechecked by the function and can have different settings.For systems which are running asynchronous a synchronizingfunction is provided. The main purpose of the synchronizingfunction is to provide controlled closing of circuit breakerswhen two asynchronous systems are going to be connected.It is used for slip frequencies that are larger than those forsynchrocheck and lower than a set maximum level for thesynchronizing function.Logic rotating switch for function selection and LHMIpresentation SLGGIOThe logic rotating switch for function selection and LHMIpresentation (SLGGIO) (or the selector switch function block)is used to get a selector switch functionality similar to the oneprovided by a hardware selector switch. Hardware selectorswitches are used extensively by utilities, in order to havedifferent functions operating on pre-set values. Hardwareswitches are however sources for maintenance issues, lowersystem reliability and an extended purchase portfolio. Thelogic selector switches eliminate all these problems.Selector mini switch VSGGIOThe Selector mini switch VSGGIO function block is amultipurpose function used for a variety of applications, as ageneral purpose switch.VSGGIO can be controlled from the menu or from a symbolon the single line diagram (SLD) on the local HMI.IEC 61850 generic communication I/O functions DPGGIOThe IEC 61850 generic communication I/O functions(DPGGIO) function block is used to send double indications toother systems or equipment in the substation. It is especiallyused in the interlocking and reservation station-wide logics.Single point generic control 8 signals SPC8GGIOThe Single point generic control 8 signals (SPC8GGIO)function block is a collection of 8 single point commands,designed to bring in commands from REMOTE (SCADA) tothose parts of the logic configuration that do not needextensive command receiving functionality (for example,SCSWI). In this way, simple commands can be sent directlyto the IED outputs, without confirmation. Confirmation (status)of the result of the commands is supposed to be achieved byother means, such as binary inputs and SPGGIO functionblocks. The commands can be pulsed or steady.AutomationBits, command function for DNP3.0 AUTOBITSAutomationBits function for DNP3 (AUTOBITS) is used withinPCM600 to get into the configuration of the commandscoming through the DNP3 protocol. The AUTOBITS functionplays the same role as functions GOOSEBINRCV (for IEC61850) and MULTICMDRCV (for LON).Single command, 16 signalsThe IEDs can receive commands either from a substationautomation system or from the local HMI. The commandfunction block has outputs that can be used, for example, toTransformer protection RET670 9-2 LE 1MRK504119-BEN BCustomizedProduct version: 1.2ABB 15