【7A文】Gas Engine Analysis（燃气发动机分析）.ppt

《【7A文】Gas Engine Analysis（燃气发动机分析）.ppt》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、GasEngineAnalysisTheIgnitionSystemTheultimatepurposeoftheignitionsystemistoignitetheair/fuelmixtureintheprecombustionchamberattheproperdegreeofcrankshaftrotationandinsurethattheflamepropagatesthroughthecombustionchamberatdesignrates.Inreality,theignitionsy

2、stemprovidestheelectricalarcacrossthesparkplugelectrodeinthepre-combustionchambertoignitedthatportionoftheair/fuelmixturepassingthroughtheelectrodecorridorduringthearcduration.Theignitionsystemhasperformeditsdesignedtaskwhenitdeliversanelectricalarcacrosst

3、heproperlyspacedelectrodesofonlythedesignedperiodoftime(arcduration).SetupConnection(secondary)CoilPlugAttenuatorAttenuatorGain(settomaximum)SecondaryIgnitionClipRecipTrapMarkerSignalSetupConnection(Primary)IgnitionJunctionBoxKillGroundAttenuatorRedWireBla

4、ckWireRecipTrapMarkerSignalPrimaryIgnitionCableCollectingIgnitionThevoltagefromignitionsignalisveryhighandcandamagethereciptrapintrument.Itisthereforeessentialtoreducethevoltageusingattenuator.Setattenuatortomaximum(500).Connectthelead.Lookatthereadingonth

5、edisplay,ifitistoosmall(under1000mV),reducetheattenuationonelevel(to100x).Thiswillincreasethereadingonthedisplaybyfactoroffive.Ifreadingstillbelow1000mV,reducetheattenuationagain.Presstrapdefbuttontorestartthesampling.Waituntilasterisk“*“appearonthedisplay

6、.Presstraptosavethedata.Donotadjusttheattenuationlevel.IgnitionCalculationExample100xattenuation.4000mVinthedisplayPrimaryignitionVoltage=>4000mVx100/1000mV/V=400VABDFGHIJCETheIgnitionSystemPrimaryIgnitionParade:A-PeakPrimaryvoltage(Capasitorfullycharged).

7、B-ZeroGroundReference.C-Degreeatwichcapasitordischarged.D-Capasitorvoltagereacheszero(fullydischarged).E-EndOfchargingcycle(capasitorfullycharged).F-Degreeorperiodoftimecapasitorholdcharge.G-SameasC.H-DtoEChangestimedegrees.I-CtoGonecompletedischargingandc

8、harging.J-Thresholdinthechargingcyclestage.TheIgnitionSystemSecondaryIgnition:I-IgnitionTimingDegree.II-PeakIonizationVoltage.III-ArcVoltage.IV-ArcDurationPeriod.V-ReserveVoltage.(ringdown)VI-De-energizedPeri