(7.1.1)--23电气主接线概述.ppt
Electrical Equipment and Operation1ContentsOverview of Electrical Main WiringDesign Requirements for Electrical Main WiringBasic Form of Electrical Main WiringONOverview of Electrical Main Wiring3Electrical Main WiringReferring to a circuit in which various electrical devices such as generators,transformers,circuit breakers,isolating switches,mutual inductors,busbars,cables,lines,etc.in power plants or substations are connected in accordance with certain requirements and sequences to complete the transmission and distribution of electrical energy.Electrical main wiring is a network that transmits strong current and high voltage,so it is also called primary wiring or electrical main system.4Overview of Electrical Main WiringDiagram of Main Electrical WiringDiagram of main electrical wiring refers to the wiring diagram in which the graphics and text symbols uniformly prescribed by the state to represent various electrical devices and arranged in the order of work to express in detail all the basic components and connection relationships of the electrical main wiring.Since the three-phase AC circuit is generally a symmetrical circuit,the main electrical wiring diagram is a single-line diagram,and some parts are represented by three-phase(current transformer,wave trap,etc.)because of the difference in the three-phase structure.5Overview of Electrical Main WiringCommonly Used Symbols for Primary Electrical DevicesNo.Device nameGraphic symbolText symbol1AlternatorG or GD2DC generatorG or GD3AlternatorM or MS4DC generatorM or MD5Double winding transformerT or TM6Three-winding transformerT or TM7AutotransformerT or TM8ReactorLNo.Device nameGraphic symbolText symbol9Split ReactorL10Lightning arresterFU11Spark gapF12Power capacitorC13RectifierU14Current transformerTA15Double winding voltage transformerTV16Three-winding voltage transformerTV6Overview of Electrical Main WiringCommonly Used Symbols for Primary Electrical DevicesNo.Device nameGraphic symbolText symbol17Transmission lineL or WL18BusbarW or WB19Cable terminalW20Disconnecting switchQ or QS21Disconnecting plugs and sockets22Circuit breakerQ or QS23Load switchQNo.Device nameGraphic symbolText symbol24Load switch with automatic releaseQ25ContactorK or KM 26Contactor with self-controlled releaseK or KM 27Low-voltage circuit breakerK or KM 28FuseFU29Drop or fuseFU30GroundingContentsOverview of Electrical Main WiringDesign Requirements for Electrical Main WiringBasic Form of Electrical Main WiringON8Design Requirements for Electrical Main Wiring(1)The importance of electrical main wiring designlThe electrical main wiring represents the main structure of the electrical part of the power plant or substation,and is an important part of the power system network structure.It directly affects the reliability and flexibility of the operation.lThe electrical wiring diagram is an important basis for electrical operators to perform various operations and accident handling.lThe electrical main wiring has a decisive relationship to the selection of electrical appliances,the layout of power distribution devices,the preparation of relay protection,automatic devices and control methods.It is the decisive factor for the investment in the electrical part of power plants and substations.9Design Requirements for Electrical Main Wiring(2)Design requirements-reliabilitySafety and reliability is the primary task of power production,and ensuring the reliability of power supply is the most basic requirement of electrical main wiring.(1)Reliability is not absoluteWhen analyzing the reliability of the electrical main wiring,the position and role of the power plant or substation in the power system cannot be separated.(2)The objective measure of reliability is operating practice(3)Reliability is directly related to the reliability of electrical equipment(4)Reliability is evolving10Design Requirements for Electrical Main Wiring(2)Design requirements-flexibilitylThe electrical main wiring should be able to adapt to the requirements of various operating modes,that is,the electrical main wiring should be able to switch between operating modes quickly and conveniently according to the requirements of dispatching.lIn the event of an accident or equipment maintenance,the fault can be removed as soon as possible,and the equipment can exit to prevent the expansion of the accident.At the same time,through flexible and simple operation,the power outage time is minimized,the impact range is minimized,and the safety of maintenance personnel can be guaranteed11Design Requirements for Electrical Main Wiring(2)Design requirements-economyEnsure safety and reliability first and then seek economyAt the same time,there should be the possibility of development and expansion lLow investment(land acquisition fee,equipment fee,installation fee,civil construction fee,etc.)lLow operating costs(equipment depreciation costs,power loss costs,maintenance costs,personnel salaries,etc.)Design Requirements for Electrical Main Wiring12Power plants and hub substations of ultra-high-voltage and large-capacity have particularly high requirements for reliability.Design Requirements for Electrical Main Wiring13Small and medium-capacity power plants and intermediate substations or terminal substations should pay special attention to the economy of their main wiring.ContentsOverview of Electrical Main WiringDesign Requirements for Electrical Main WiringBasic Form of Electrical Main WiringON15Basic Form of Electrical Main WiringBasic linkPower supply(generator or transformer),busbar and outlet(feeder).The basic composition of electrical main wiring is electrical equipmentBusbarWhen the number of power supply and the number of outgoing wires are not equal,in order to facilitate the collection and distribution of electric energy,the busbar is used as an intermediate link,which can make the wiring simple and clear,convenient for operation,and beneficial to expansion.However,with the busbar,the power distribution device occupies a larger area,and the use of circuit breakers and other equipment increases.16Basic Form of Electrical Main WiringMain wiring classificationBusbar typeBusless typeUnit wiringBridge wiringPolygonal wiringSingle busbarDouble busbarSimple single busbarSectionalized configurationSectionalized configuration with bypassSimple double busbarDouble busbar configurationDouble busbar with bypassDouble circuit breaker and double busbarFractional circuit breaker double busbar(3/2 wiring)Thank you for watching!17
