汽车电子--点火线圈变压器结构原理

product training ignition transformerOct. 2007product training ignition transformerSession 1: Basic function of gasoline four stroke engine and the function of ignition system. Objective target: To recognize what an modern ignition system do in the engine.Oct. 2007Position and function of and engine in a carFirst of all the engine of a car is responsible to produce the force and the power to move the car. They are also responsible to charge the battery, to power the air conditioner, to power the steering booster and so on.cardan shaft enginegearboxaxisOct. 2007History of 4 stroke gasoline enginefirst 4 stoke enginecar enginemodern racing engineapprox. 186719671997Oct. 2007Future of 4 stroke gasoline engineEngine BMW S65Cylinders/valves Capacity in ccm Stroke/bore in mm Max. output in kW at 1/min Max. torque in Nm at 1/min 8/4 3.999 75.2/92.0 309 (420)/8,300 400/3,900Ignition coil with integrated ion current sensing made by pulse. This coil is used in the new S65 engine of BMW start of production 2007Oct. 2007elementary function of an 4 stroke gasoline engineStep 1: • Intake valve opens • Piston moves down • A mixture of air and gasoline gets into the cylinder because of the low pressureStep 2: • Intake valve closes • Piston moves up • The mixture of air and gasoline is compressedStep 3: •A high voltage is applied to the spark plug•Step 4: •The exhaust valve opens •The piston moves up•A sparkover between •Because of the rising the electrodes happens pressure the exhaust •The sparkover is very gas is moved out of hot and ignites the the cylinder fuel-air mixture •Because of the explosion the piston moves downOct. 2007elementary function of an 4 stroke gasoline engineStep 1: • • • Intake valve opens Piston moves down A mixture of air and gasoline gets into the cylinder because of the low pressureOct. 2007elementary function of an 4 stroke gasoline engineStep 2: • • • Intake valve closes Piston moves up The mixture of air and gasoline is compressedOct. 2007elementary function of an 4 stroke gasoline engineStep 3: • • • A high voltage is applied to the spark plug A sparkover between the electrodes happens The sparkover is very hot and ignites the fuel-air mixture Because of the explosion the piston moves down•Oct. 2007elementary function of an 4 stroke gasoline engineStep 4: • • • The exhaust valve opens The piston moves up Because of the rising pressure the exhaust gas is moved out of the cylinderOct. 2007function of the ignition system in an engine• Information from engine controller unit when to spark • Connection to 12V battery for supplyVery hot Sparkover ignites fuel-air mixture inside the cylinderHigh voltage pulse up to 30kVOct. 2007Traditional central ignition systemsca bl e scableignition coil•In older ignition system there is one ignition coil for all cylinders. The high voltage for all spark plugs is generated by this coil. The voltage is distributed by a rotating switch which is called distributor. So you have to transport a voltage up to 30kV through cables inside the engine compartment.Oct. 2007distributor•Modern ignition system•Newer cars have one ignition transformer on each spark plug. So the high voltage is produced where it is needed and you do not have to transport it. This gives a more reliable system and lower emc interferences.•ignition coils (pencil coils)spark plugsOct. 2007product training ignition transformerSession 2: Principle function of an modern ignition coil Objective target: Understanding in which way an ignition coil produces the Spark respectively the high voltage.Oct. 2007main parts of a pencil coilbatteryresin for electrical insulationswitchOct. 2007outer metal sheetsecondary coilprimary coiliron coremain parts of a pencil coil1. switch closes batteryresin for electrical insulationswitch2. electrical current through primary coilOct. 2007outer metal sheetsecondary coilprimary coiliron coremain parts of a pencil coilbatteryresin for electrical insulationswitchelectrical current through primary coil3. electrical current causes magnetic field and magnetic energy is stored in the iron coreOct. 2007outer metal sheetsecondary coilprimary coiliron coremain parts of a pencil coil4. switch opens batteryresin for electrical insulationswitch5. electrical current through primary coil stopsOct. 2007outer metal sheetsecondary coilprimary coiliron coremain parts of a pencil coilbatteryresin for electrical insulationswitch6. magnetic field disappears and induces high voltage in secondary windingsouter metal sheet 7. high voltage on spark plug leads to sparkoverOct. 2007secondary coilprimary coiliron coreIgnition coil Operatingtime response:switch on off primary current 8...15A t charget secondary voltage discharge 1000V 10...30kV t 100mA tsecondary currentOct. 2007Green:secondary voltage at spark plugOct. 2007Ignition transformer-functional viewconclusionAll ignition coils made by Pulse are inductive transformers.All ignition coils from Pulse work without a high-voltage distributor. That means every spark plug has it’s own ignition coil.All ignition coils include two windings, a primary and a secondary. Both windings are always on the same iron core. The iron core is needed to store the energy.Each coil system has a transistor (mostly an IGBT) which controls the primary winding. Sometimes, the transistor is integrated into the coil, e.g. VW/AUDI coils, and sometimes the transistor is in the engine control unit (ECU), e.g. BMW coils.Oct. 2007product training ignition transformerSession 3:Parts of our ignition coils, their function andrequirementsObjective target:The attendees know the critical parts andthere function in the ignition systemOct. 2007Silikonverguss Silicon resinKontaktfeder contact springFlachbandfeder flat band spring Primaerkontakt primary contactSchutzschlauch flexible conduit Platine PCBHS-Verlaengerung HV extensionAussenblechexternal sheet metalBuegelfeder yoke springSchrumpfschlauch shrink hoseEntstoerwiderstand EMC resistorRundkernlaminated round coreRundmagnetround permanent magnet PadHarzepoxy resinWickelstift HS HV pin Sekundaerspule secoundary coil Primaerspule primary coil Abstuetzung supportSpulenkopf plastic headHS-Adapter HV adapter EMV Dichtung EMC sealingDeckel capVW/AUDI Oct. 2007Oct. 2007primary coil •Change electrical energy into magneticenergy •Has to withstand high voltages (electrical fieldstrengths)•Needs good adhesion to epoxy resin insidehv-adaptor with emcresistor •Reduce emc-interferences caused bythe spark•Flexible contact to hv-extension •Must have exact size to seal unit during potting process without cracking the primarybobbinsecondary coil •Transform magnetic energy into electricalenergy •Has to withstand high voltages (electrical fieldstrengths) •Needs good adhesionto epoxy resiniron core module •Store magnetic energy•Compensate different thermal coefficients of iron and epoxy resin / secondary bobbinr e q u i r e m e n t sm a i n f u n c t i o n p a r tOct. 2007r e q u i r e m e n t sm a i n f u n c t i o n p a r touter metal sheet •store magnetic energy •conduct magnetic field •Has to be rust-free even in case of moisture in spark plug shaft •magnetical parameters have to be correctcontact •contact pcb low inductive to enginegroundplastic head •connect primary connector, metal shieldand coil system •color (red/black) is customer specific •Has to withstand up to140°COct. 2007r e q u i r e m e n t sm a i n f u n c t i o n p a r tmetal shielding •protect silicone hose •connect outer metal shield to spark plug •Has to be rust-free even in case of moisture in spark plug shaftsilicone hose •isolate high voltage tospark plug shaft•Has to withstand high voltages (electrical fieldstrengths) •Has to withstand temperatures up to220°CHigh voltage extension •connect high voltageto spark plug •mechanically fix coil onspark plugOct. 2007r e q u i r e m e n t sm a i n f u n c t i o np a r tElectronic with primary connector •contains transistor switch (IGBT)•starts and stops loading process of the magneticsystem •Realizes some additional protective functions •Contains elements to decrease electromagneticdisturbances caused by the product•reduces turn on high voltage pulse•Has to be lead free•Has to have good adhesion to epoxy resin •Soldering have still to be good after hundreds ofcycles of thermal shockingproduct training ignition transformerSession 4:Reliability monitoring; test conditions failureanalysisObjective target:To learn what are the critical parameters andwhat we can get from the reliability monitoringresults.Oct. 2007Oct. 2007reliability monitoring test for BMW (car and motorbike)ECU simulators:They are needed to run the coils with electrical stress in the thermo shock chamber. This is necessary for BMW reliability test for motorbike, S85 and 12144Control unit for ECU simulators to setup the parameters and monitor thecoil functionOct. 2007Lab station for testing ignition coilspower supplyTesting coilHV test probescopeECU simulation unit to drive coil in Labcracks ElectricalbreakdowncracksElectricalbreakdown。