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1、功率因素测量用0-90余弦表Thepowerfactormetercanonlymeasurethepoweroftheloadcircuit,becausethevaluecannotindicatewhethertheloadisinductiveorcapacitiveIfthecapacitiveload(capacitor),thenhewillleadtothefinalcurrentof90degrees,andifitisinductance,thefinalcurrentwill
2、produce-90degrees(thatis,lag90degrees)LeadandlagarecausedbycapacitiveloadsandinductiveloadsinthegridIfthecapacitiveloadinthegridisgreaterthantheinductiveload,thecapacitanceiscapacitive,thecurrentisadvanced,andthepowerfactorisnegativeIftheinductiveload
3、inthegridisgreaterthanthecapacitiveload,thecapacitorisinductive,thecurrentlagvoltage,andthepowerfactorispositiveIsthecurrentlag,voltage,powerfactorispositive,atthistimeisinductiveload;onthecontrary,thecurrentleadvoltage,powerfactorisnegative,atthistim
4、eiscapacitiveload.Whentheinductiveloadisgreaterthanacertainvalue,thecapacitorcanbeputintocompensation,andthecapacitancecanberemovedwhenthecapacitiveloadisgreaterthanacertainvalue.Ageneralelectronicinstrumentdisplayisrepresentedbysensiblecapacitiverath
5、erthanpositiveandnegativesigns.Iftheactivepowerisnegative,thecurrentreverses.Otherwise,itisOKtomakenormalcompensationaccordingtothereactivepowerThePowerSupplyBureaurequiresthepowerfactorabove0.9,andthis0.9istheabsolutevalue,regardlessofthecapacitivese
6、nsibility.Ifthecapacitiveloadinthegridisgreaterthantheinductiveload,thecircuitiscapacitive,currentleadingvoltage,powerfactorcosPhiahead,powerfactoranglephi<0Iftheinductiveloadinthegridisgreaterthanthecapacitiveload,thecircuitisinductive,thecurrenthyst
7、eresisvoltage,thepowerfactorcosPhilags,andthepowerfactoranglephi>01.inductionformulaCos(alpha)=cos(a)Cos(n-a)=cos(a)Cos(n+a)=cos(a)Cos(2kPI+alpha)=cosalphaCos(2pi)=cosalpha1.forjust0-90YuXianbiao2.when08、-a,getthevalue,checkthe0-90table,takethenegativevalue,COS,a=-cos(PI-a)4.when180