ECP SECONDARY SUBSTATION ENERGISATION PROCEDURE

Transcription

1 Document Number: ECP Network(s): Summary: ENGINEERING COMMISSIONING PROCEDURE ECP SECONDARY SUBSTATION ENERGISATION PROCEDURE EPN, LPN, SPN This procedure details the energisation procedures for secondary distribution substations, and includes high voltage insulation testing, energisation and postenergisation checks, which shall be satisfied before the substation can be accepted as fit for service. Author: Stephen Tucker Approved By: Paul Williams Approved Date: 26/10/2016 This document forms part of the Company s Integrated Business System and its requirements are mandatory throughout UK Power Networks. Departure from these requirements may only be taken with the written approval of the Director of Asset Management. If you have any queries about this document please contact the author or owner of the current issue. Applicable To UK Power Networks All UK Power Networks Asset Management Capital Programme Connections HSS&TT Network Operations UK Power Networks Services Other External G81 Website Contractors ICPs/IDNOs Meter Operators THIS IS AN UNCONTROLLED DOCUMENT, THE READER MUST CONFIRM ITS VALIDITY BEFORE USE

2 Revision Record Version 5.0 Review Date 04/12/2020 Date 18/10/2016 Author Stephen Tucker Why has the document been updated: Introduction of new HV metering unit What has changed: Testing customer HV cables added (Section 6) Version 4.0 Review Date 04/12/2020 Date 04/12/2015 Author Stephen Tucker Why has the document been updated: Renumbering of referenced documents What has changed: HV insulation testing and HV polymeric cable sheath testing document references updated (Section 6). Labelling of Pfisterer sockets added (Section ) Version 3.0 Review Date Date 06/12/2013 Author Stephen Tucker/ Paul Williams Procedure for testing new polymeric insulated cables added (Section 6) Version 2.2 Review Date Date 04/11/2013 Author Stephen Tucker Document type corrected Version 2.0 Review Date Date 12/08/2013 Author Stephen Tucker Updated to reflect current operational practice across all three networks. Sheath test added (Section 6). Test forms removed and incorporated into ECP Version 1.3 Review Date Date 17/08/2012 Author Lee Strachan Reviewed for publication on G81 Website Version 1.2 Review Date Date 13/09/2011 Author John Lowe Document renumbered Version 1.0 Review Date Date 05/02/2010 Author Alan Baldock/ Stephen Tucker Original UK Power Networks 2016 All rights reserved 2 of 14

3 Contents 1 Introduction Scope References Abbreviations and Definitions Equipment HV Cable Tests Energisation Process Overview Initial Configuration Energisation using a Phase Comparator Energisation at Sites with LV Backfeed Energisation at Sites without LV Backfeed Energisation at Sites using an End-to-End Test Post-energisation Checks Final Checks Test Equipment Certification Asset Data and Information UK Power Networks Independent Connection Provider (ICP) Appendix A Phasing Checks UK Power Networks 2016 All rights reserved 3 of 14

4 1 Introduction 1.1 This procedure details the energisation procedures for secondary distribution substations, and includes high voltage insulation testing, energisation and postenergisation checks, which shall be satisfied before the substation can be accepted as fit for service. 1.2 This procedure shall be carried out by the Commissioning Engineer or his appointed representative, who shall be an Authorised Person having appropriate training and experience. 1.3 This procedure shall be carried out in accordance with the requirements of the UK Power Networks Distribution Safety Rules. 1.4 This procedure shall be carried out having regard to the requirements and recommendations of the manufacturer. If conflict exists between the requirements of the manufacturer and those of UK Power Networks the matter shall be referred to Asset Management (or your UK Power Networks nominated contact). 1.5 This procedure assumes the following: The transformer has been commissioned in accordance with ECP of the commissioning manual. The HV switchgear has been commissioned in accordance ECP /ECP The fault passage indicator (FPI) has been commissioned in accordance with section ECP , if applicable. The necessary protection settings have been applied. The substation and all equipment are correctly earthed. 1.6 The results of all observations, tests, adjustments and all relevant remarks shall be recorded on the appropriate test form. 2 Scope 2.1 This procedure and the associated test form(s) applies to the energisation of 11kV and 6.6kV secondary distribution substations. 2.2 Although not specially covered within this procedure the principles can be applied to the energisation of an item of new equipment at a substation. The actual process should be agreed between the Authorised Person and the Control Engineer. UK Power Networks 2016 All rights reserved 4 of 14

5 3 References 3.1 This procedure should be read in conjunction with the following references: HSS High Voltage System Phasing Checks. ECS HV Insulation Testing. ECP HV Polymeric Cable Sheath Testing Procedure. ECP Ground Mounted Switchgear Commissioning Procedure. ECP Ground Mounted Switchgear with Relays Commissioning Procedure. ECP Nortroll Cable Troll 2350 FPI Installation and Commissioning Procedure. 3.2 This procedure should be used with the following test forms: ECP a Secondary Substation Commissioning Form. ECP a HV Polymeric Cable Sheath Test Form. 4 Abbreviations and Definitions 4.1 The following abbreviations are used throughout this procedure. Term ART CT VT Definition UK Power Networks Asset Registration Team Current Transformer Voltage Transformer 5 Equipment 5.1 The following test equipment is required to carry out the tests detailed in this procedure: High voltage testing equipment (5kV insulation resistance tester, HV AC test set or HV DC test set). Pfisterer K F phase comparator (refer to HSS ). Test lamp. Multi-meter. UK Power Networks 2016 All rights reserved 5 of 14

6 6 HV Cable Tests 6.1 Record the substation details on the test form. 6.2 Carry out sheath tests on all new polymeric insulated HV cable prior to connection in accordance with ECP and record the overall result on test form ECP a. 6.3 Carry out high voltage insulation tests on all HV cables after connection to the existing distribution network in accordance with ECS and record the results on test form ECP a. Carry out high voltage insulation tests on all new customer HV cables in accordance with ECS and record the results on test form ECP a. Note: Where it is not practical, due to the design of the HV metering unit, to disconnect the VT the customer cable should be tested after the cable terminations have been completed but before the cable is connected to the metering unit. UK Power Networks 2016 All rights reserved 6 of 14

7 7 Energisation Process 7.1 Overview 7.2 The energisation process detailed in this section are based on high voltage system phasing checks outlined in HSS The process shall be carried out in accordance with the Distribution Safety Rules ensuring that the correct safety documentation is in place Record the results on test form ECP a. Note: This process covers the energisation of a substation using a phase comparator (Pfisterer) which is the safest method of energisation; however this method will not detect a roll on both sides of a HV cable which although not a dangerous situation is likely to cause inconvenience in the future. Traditional methods of energising substations with and without LV backfeeds are also included for completeness. 7.3 Initial Configuration The new substation is named Sub New. It has been inserted in a ring between existing substations Sub A and Sub B as shown below. Sub C Sub A Sub New Sub B Circuit Main Earths (CME) are in place at: Sub A on the Sub New substation circuit. Sub B on the Sub New substation circuit The Sub New substation has been installed and the cables terminated. 7.4 Energisation using a Phase Comparator This section describes the process for energising a site with or without an LV backfeed. All switching operations shall be carried out in accordance with normal control procedures. UK Power Networks 2016 All rights reserved 7 of 14

8 7.4.2 Step 1 Switching Operations Close both switches and the transformer circuit-breaker at Sub New. Remove Earth at Sub B on the Sub New circuit. Remove Earth at Sub A on the Sub New circuit. The network status on completion of Step 1 is shown below. Sub A Sub New Sub B Step 1 Items Proved None Step 2 Switching Operations At Sub A close Sub New switch. The network status on completion of Step 2 is shown below. Sub A Sub New Sub B Step 2 Checks Using the Phase Comparator At Sub New on Sub A switch, all 3 Voltage Indicating Sockets (VIS) indicate Live and out of phase with each other. At Sub New on Sub B switch, all 3 VIS indicate Live and out of phase with each other. At Sub New confirm HV phasing indication between: Sub A Switch Sub B Switch Phasing L1 L1 IN L1 L2 OUT L2 L2 IN L2 L3 OUT L3 L3 IN L3 L1 OUT Where L1 = R, L2 = Y and L3 = B. Check the voltage and phase rotation at the LV cabinet/board. If Sub New is or will be connected to a local interconnected LV network, then the phase relationship of Sub New site with that existing network should also be proved at this stage of commissioning, wherever possible. UK Power Networks 2016 All rights reserved 8 of 14

9 7.4.6 Step 2 Items Proved The VIS on both switches at Sub New are connected to the same respective cable box bushings (i.e. L1, L2 and L3 are the same HV phases on both switches). The Pfisterer phase comparator is configured correctly for the type of switchgear under test (i.e. Lucy, Schneider). The LV voltage is correct Step 3 Switching Operations At Sub New open Sub A switch. The network status on completion of Step 3 is shown below. Sub A Sub New Sub B Step 3 Checks At Sub New on Sub A switch, check all 3 VIS indicate Live. At Sub New on Sub B switch, check all 3 VIS indicate Dead. At Sub New confirm that the transformer is Dead Step 3 Items Proved Switch labelling is correct at Sub New. All three cores from Sub A cable are connected to switch Sub A at Sub New. VIS on Sub A switch are connected to cable side of Sub A switch. VIS on Sub B switch are not connected to Sub A side Step 4 Switching Operations At Sub New open Sub B switch. At Sub B close New substation switch. The network status on completion of Step 4 is shown below. Sub A Sub New Sub B UK Power Networks 2016 All rights reserved 9 of 14

10 Step 4 Checks At Sub New on Sub B switch, check all 3 VIS indicate Live. At Sub New confirm that the transformer is Dead. Ensure Pfisterer phase comparator connections are the same as phase checks in Step 2. At Sub New using the phase comparator confirm the HV phasing between: Sub A Switch Sub B Switch Phasing L1 L1 IN L1 L2 OUT L2 L2 IN L3 L2 OUT L3 L3 IN L3 L1 OUT Step 4 Items Proved VIS on Sub B switch are connected to cable side of Sub B switch. Cables from Sub A and Sub B are in phase Step 5 Switching Operations Restore network to final running arrangement On completion of the test install a label next to the VIS sockets as shown in the example below. UK Power Networks 2016 All rights reserved 10 of 14

11 7.5 Energisation at Sites with LV Backfeed This section describes the traditional process for energising a site with an LV backfeed Step 1 At Sub New close Sub A switch and the transformer circuit-breaker. At Sub A remove earth on the Sub New circuit. At Sub A close Sub New switch. At Sub New phase out at the LV cabinet. At Sub New open Sub A switch. Check transformer is Dead via the LV cabinet/board Check labels Step 2 At Sub New close Sub B switch. At Sub B remove earth on the Sub New circuit. At Sub B close Sub New switch. At Sub New phase out at the LV cabinet/board. At Sub New confirm HV phasing indication using Phase Comparator: Sub A Switch Sub B Switch Phasing L1 L1 IN L1 L2 OUT L2 L2 IN L2 L3 OUT L3 L3 IN L3 L1 OUT At Sub New open Sub B switch. Check transformer is dead via the LV cabinet/board Check labels Restore network to the final running arrangement. UK Power Networks 2016 All rights reserved 11 of 14

12 7.6 Energisation at Sites without LV Backfeed This section describes the traditional process for energising a site without an LV backfeed Where there is no LV reference at the new substation, the circuit can be energised all the way from Sub A to Sub B. Sub B is made dead and then re-energised by closing the incoming feed from Sub A (via New substation). Phasing is then carried out at transformer way in Sub B. A rotation check is carried out at the Sub New to check for a double cross Step 1 At Sub New close Sub A switch and Sub B switch. At Sub A and Sub B remove earth on the Sub New circuit. At Sub A close Sub New switch. At Sub B apply LV backfeed and open LV isolator. At Sub B open Sub C switch and close Sub New switch. At Sub B phase out at the LV cabinet/board. At Sub New open Sub A switch. Check labels. At Sub New check phase rotation at LV cabinet/board. Restore LV network to normal at Sub B Where it is not possible to backfeed or switch off Sub B (e.g. dedicated LV supplies or HV supply) phasing using an end-to-end test is permissible (refer to Section 7.7) Restore network to the final running arrangement. 7.7 Energisation at Sites using an End-to-End Test Where none of the above methods are possible, where practicable an end-to-end phase check is permissible in accordance with HSS UK Power Networks 2016 All rights reserved 12 of 14

13 8 Post-energisation Checks 8.1 Record the substation details on the test form. 8.2 Carry out the relevant checks detailed below and complete the relevant sections of test from ECP a. Measure the voltage at the LV cabinet/board. For sites with LV backfeed phase out at the LV cabinet/board using a test lamp. For sites without LV backfeed check phase rotation at the LV cabinet/board. 9 Final Checks 9.1 On completion of the energisation process ensure that: The network is restored to final running arrangement. The LV isolator is closed. 10 Test Equipment 10.1 Record the purpose, make, type and serial number of all test equipment used during commissioning on the relevant test form. 11 Certification 11.1 When all the tests have been satisfactorily completed, sign and date the test form Place a copy of the completed test form on-site in a plastic wallet and in a secure location. 12 Asset Data and Information 12.1 UK Power Networks Send a copy of the completed test form to the Asset Registration Team (ART) via the appropriate mailbox below. ART.EPN@ukpowernetworks.co.uk. ART.LPN@ukpowernetworks.co.uk. ART.SPN@ukpowernetworks.co.uk Independent Connection Provider (ICP) Send a copy of the completed test form to the Competition-in-Connections Delivery Project Manager. UK Power Networks 2016 All rights reserved 13 of 14

14 Appendix A Phasing Checks Phasing Checks Test Sub A New Sub B New Substation New SW Sub A SW Sub B SW CB New SW Sub A SW Sub B SW 1 Open Closed Closed Closed Open Starting arrangement 2 Closed Closed Closed Closed Open 3 Closed Open Closed Closed Open 4 Closed Open Open Closed Closed L1-L2-L3 Live L1-L2-L3 Live L1 L1 IN Phasing OUT OUT L1 L2 OUT L2 L2 IN L2 L3 OUT L3 L3 IN L3 L1 OUT Transformer Live L1-L2-L3 Live L1-L2-L3 Dead Transformer Dead L1-L2-L3 Live L1-L2-L3 Live L1 L1 IN OUT OUT L1 L2 OUT L2 L2 IN L2 L3 OUT L3 L3 IN L3 L1 OUT Transformer Dead () UK Power Networks 2016 All rights reserved 14 of 14