Switching Operator's Manual Distribution Switching

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Switching Operator's Manual Distribution Switching Switching Operator’s Manual Distribution Switching Document Number: 5011675 SECTION ONE Introduction: Distribution Switching Table of Contents 1. Introduction: Distribution Switching ...................................................... 1-1 1.1 Purpose .............................................................................................. 1-1 1.2 Content .............................................................................................. 1-1 1.2.1 Manual One .................................................................................... 1-1 1.2.2 Manual Two .................................................................................... 1-3 1.3 Switching Operator Authorisation Levels ............................................ 1-3 i Switching Operator's Manual One List of Figures No table of figures entries found. List of Tables No table of figures entries found. ii 1. Introduction: Distribution Switching 1.1 Purpose Manual One provides the switching operator with information on the distribution network configuration, apparatus and switching operations. The manual covers the Horizon Power distribution networks associated with the microgrid and Pilbara Grid systems. Manual Two provides the switching operator with information on the transmission network configuration, apparatus and switching operations. This manual covers the transmission network associated with the Pilbara Grid. Both manuals are intended to be used as a resource for all switching operators and also a major resource for the training modules in Switching Operations. 1.2 Content 1.2.1 Manual One Manual One covers the network and switching associated with the distribution high voltage (HV) and low voltage (LV) network, which is common to both microgrid and Pilbara Grid systems. The LV distribution network connects electrical power to the majority of the Horizon Power’s customers, and the HV distribution network supplies HV power to the distribution transformers which is stepped down in voltage to supply the LV network. A brief description of the contents of each section is provided below. Section 1 Section One (this section) provides a brief overview of the contents of the manuals and a more detailed overview of the sections related to the distribution HV and LV networks. Section 2 Section Two is a general introduction to Horizon Power’s Power systems. It provides an overview of both microgrid and the interconnected Pilbara Grid systems. An overview of generation stations, transmission substations and lines and the distribution HV and LV networks is provided. The responsibility for switching on these networks is also discussed. 1-1 Switching Operator's Manual One Section 3 Section Three describes in detail the LV distribution network configuration, apparatus and switching operations. This is the most extensive network and both overhead and underground forms are common. This network connects and provides electrical power to the majority of Horizon Power’s customers. Section 4 Section Four describes in detail the HV distribution overhead network configuration, apparatus and switching operations. This is an extensive network and exists in both three-phase and the single-phase forms common in regional areas. Section 5 Section Five describes in detail the HV underground network configuration, apparatus and switching operations. This network tends to be located in built-up areas and exists in both three-phase and the single-phase forms. Section 6 Section Six describes in detail the substations which provide the source of supply for the HV distribution network. It includes a description of the substation configurations and the associated primary and ancillary apparatus. Section 7 Section Seven describes the protection systems used on both the HV and LV distribution systems. It includes descriptions of the grading introduced to ensure only the faulted section of the distribution system is disconnected. Section 8 – (also applicable to Transmission switching) Section Eight describes the critical matters relating to safe switching operations, it is applicable to both distribution and transmission switching. The section includes a description of the switching related documentation and the roles and responsibilities. Also detailed are the principles and practice of isolation and earthing, permits and barriers, locking and tagging. Details are provided on common switching operation tasks, the practical checks before and after switching apparatus and switching related hazards. Section 9 – (also applicable to Transmission switching) Section Nine describes the roles and responsibilities, tools and procedures associated with the creation and running of switching programs which are applicable to both distribution and transmission switching. Also included in the section are the program writing considerations which must be reflected on and included if appropriate to create a successful switching program. 1-2 Section One – Introduction: Distribution Switching Section 10 Section 10 describes the testing and commissioning documentation, equipment and practices required to carry out the testing and commissioning of distribution apparatus which is to be placed in service. Also included is an example of a commissioning switching program. 1.2.2 Manual Two Manual Two covers matters relating to transmission network switching. It should be noted Sections 8 and 9 as described above are also applicable to transmission switching. 1.3 Switching Operator Authorisation Levels Horizon Power's Switching Operator Authorisation Levels are described in the table below. Level Description 1 Fault response – initial response to faults including switching to disconnect faulted apparatus on de-energised distribution systems. 2 Distribution switching – all primary apparatus associated with HV and LV overhead and underground networks. 3 Substation switching – allows switching operations on primary apparatus located within Pilbara Grid and microgrid substations. 4 Transmission switching – all primary apparatus associated with Transmission lines, zone substations and terminal stations. 5 Protection and other secondary systems – isolation and commissioning of protection and secondary systems. 6 Generation switching – HV and LV switching on generation sites. 7 HPCC controller switching – switching coordination and remote switching of Pilbara Grid and microgrid apparatus. Field Instruction – Switching Authorisation details the requirements of obtaining a switching operator’s authority. 1-3 SECTION TWO Horizon Power’s Power Systems Table of Contents 2. Horizon Power’s Power Systems ........................................................... 2-1 2.1 Introduction......................................................................................... 2-1 2.2 Horizon Power's Two Systems ........................................................... 2-1 2.2.1 Microgrid Systems .......................................................................... 2-1 2.2.2 Interconnected Systems ................................................................. 2-4 2.3 System Components .......................................................................... 2-7 2.3.1 Generating Stations ........................................................................ 2-7 2.3.2 Transmission Lines ......................................................................... 2-9 2.3.3 Terminal Stations .......................................................................... 2-10 2.3.4 Zone Substations .......................................................................... 2-13 2.3.5 Distribution High Voltage Feeders – Underground Overhead ....... 2-16 2.3.6 Distribution Low Voltage (LV) Circuits ........................................... 2-16 2.3.7 Component Responsibility ............................................................ 2-18 2.4 Connection of Components .............................................................. 2-18 2.5 Switching Responsibility ................................................................... 2-19 i Switching Operator's Manual One List of Figures Figure 2-1 Horizon Power's microgrid and interconnected systems ................... 2-2 Figure 2-2 Components of a microgrid system ................................................... 2-3 Figure 2-3 Components of an interconnected system ........................................ 2-5 Figure 2-4 Interconnected system: The interconnection of components ............. 2-6 Figure 2-5 Typical gas turbine generator............................................................ 2-8 Figure 2-6 Typical diesel fuel-fired power station ............................................... 2-8 Figure 2-7 Horizon Power’s Pilbara Grid transmission system ........................... 2-9 Figure 2-8 South Hedland Terminal Station ..................................................... 2-11 Figure 2-9 Hedland Terminal Station ............................................................... 2-12 Figure 2-10 Anderson Street Zone Substation ................................................. 2-14 Figure 2-11 Wedgefield Zone Substation 66kV single busbar .......................... 2-15 Figure 2-12 Typical distribution feeders ........................................................... 2-17 List of Tables Table 2-1 Responsibility for components ......................................................... 2-18 Table 2-2 System advantages and disadvantages ........................................... 2-19 ii 2. Horizon Power’s Power Systems 2.1 Introduction Horizon Power generates,
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