6.1 CapacitorIdealized characteristics:1) Pure capacitanceHT2) Voltage cross terminals is not changed abruptlyduCdtReal characteristics:CoESRRoESLLo()HCoESLLoIH(2)EPRRo
Idealized characteristics: 1) Pure capacitance 2) Voltage cross terminals is not changed abruptly Real characteristics: Co ESR Ro ESL Lo Co EPR Ro ESLLo (1) (2) 6.1 Capacitor
Basictypesof capacitorforPE converters:1.Aluminum CapacitorHavingasignificanteguivalentSeriesResistance(ESR)Forlow-frequency ripple currents, ESL can beneglectedtherippleismainlydeterminedbyRoandCo2. Metalized Polypropylene Capacitor68Havingaverysmall losscoefficientofthepolypropylenedielectric material.In snubbersandThyristorcommutationcircuits,theMPCisusuallyservedtoapplications3.Ceramic CapacitorHavingextremelylowseriesinductanceTheyareusedasfilters,decoupledcapacitoron PCB etc
Basic types of capacitor for PE converters: 1. Aluminum Capacitor Having a significant equivalent Series Resistance (ESR). For low-frequency ripple currents, ESL can be neglected, the ripple is mainly determined by Ro and Co. 2. Metalized Polypropylene Capacitor Having a very small loss coefficient of the polypropylene dielectric material. In snubbers and Thyristor commutation circuits, the MPC is usually served to applications. 3. Ceramic Capacitor Having extremely low series inductance. They are used as filters, decoupled capacitor on PCB etc
6.2 inductor / TransformerIdealizedcharacteristics:1)Pureinductance2)Current through it is not changed abruptly3)u=ExcitingCurrentiszerointransformerRealcharacteristics:ESRRoESCCoH(1)ESRRo(2)HHEPCCo
6.2 inductor / Transformer Idealized characteristics: 1) Pure inductance 2) Current through it is not changed abruptly 3) Exciting Current is zero in transformer Real characteristics: (1) (2) ESR Ro EPC Co Lo ESC Co ESR Ro Lo
BasictypesofinductorforPEconverters:1.Ferromagnetic coreinductorHaving asignificant inductance,but with core loss andcharacteristics ferromagnetic core (hysteresis loop andsaturationissues2.Air core inductorHaving a small value of inductance, butwithoutferromagneticissues.Applicationareas:highfrequencyandlowinductancevalue,suchassoft-switchingtechniques.PowerElectron2cos
PowerElectroni2c0s Basic types of inductor for PE converters: 1. Ferromagnetic core inductor Having a significant inductance, but with core loss and characteristics ferromagnetic core (hysteresis loop and saturation issues 2. Air core inductor Having a small value of inductance, but without ferromagnetic issues. Application areas: high frequency and low inductance value, such as soft-switching techniques
6.3PowerDevices(1) Uncontrollable Devices (No signal for both turn-on & turn-off)K4Power Diode(2)ControllableDevices(Signalforboth turn-on&turn-off)*BJTVDMOSFIGBTGTO (IGCT)-(3)Semi-controllable Devices (Signal for turn-on, no signal for turn-off)KThyristor,orSCRC
6.3 Power Devices (1) Uncontrollable Devices (No signal for both turn-on & turn-off) (2) Controllable Devices (Signal for both turn-on & turn-off) Power Diode A K C E B A G K C VDMOS IGBT G E BJT GTO (IGCT) (3)Semi-controllable Devices (Signal for turn-on, no signal for turn-off ) Thyristor, or SCR K