Muab kev hloov pauv hom pWM tawm tswv yim tswj hom
Basic Principles of Switching Power Supply pWM
Qhov hloov zaus ntawm pWM feem ntau yog qhov tsis tu ncua, thiab cov qauv ntsuas ntsuas muaj xws li: cov zis voltage, input voltage, tso zis tam sim no, tso zis inductor voltage, thiab ncov tam sim no ntawm lub tshuab hloov. Cov teeb liab no tuaj yeem tsim ib lub voj, ob lub voj, lossis ntau lub voj kev tawm tswv yim kom ua tiav qhov hluav taws xob ruaj khov, tam sim no, thiab lub zog tsis tu ncua, thaum tseem muab cov haujlwm ntxiv xws li kev tiv thaiv overcurrent, tiv thaiv kev tsis ncaj ncees, thiab kev sib koom tam sim no. Tam sim no muaj tsib lub ntsiab pWM tawm tswv yim tswj hom.
Feem ntau hais lus, lub hom phiaj tseem ceeb hauv pem hauv ntej tuaj yeem ua kom yooj yim los ntawm phaw chopper qhia hauv daim duab 1, qhov twg Ug sawv cev rau pWM tso zis tsav tsheb teeb liab ntawm kev tswj Circuit Court. Raws li kev xaiv ntawm pWM tawm tswv yim sib txawv hom, input voltage Uin, tso zis voltage Uout, hloov ntaus ntawv tam sim no (coj tawm ntawm point b), thiab inductor tam sim no (coj tawm ntawm point c lossis point d) hauv Circuit Court tuaj yeem ua tau txhua yam. siv raws li sampling control signals. Thaum cov zis hluav taws xob Uout siv los ua lub teeb liab tswj kev ntsuas, nws feem ntau ua tiav los ntawm lub voj voog uas pom hauv daim duab 2 kom tau txais cov teeb liab voltage Ue, uas yog tom qab ntawd ua tiav lossis xa ncaj qha mus rau pWM maub los. Lub tshuab hluav taws xob ua haujlwm hluav taws xob (e / a) hauv daim duab 2 muaj peb lub luag haujlwm: ① Amplify thiab tawm tswv yim qhov txawv ntawm qhov tso zis hluav taws xob thiab qhov muab hluav taws xob Uref kom ruaj khov hluav taws xob tswj qhov tseeb hauv lub xeev khov kho. DC amplification nce ntawm qhov kev ua haujlwm amplifier yog qhov kev xav tsis kawg, tab sis qhov tseeb, nws yog qhov qhib-voj amplification nce ntawm kev ua haujlwm amplifier Hloov lub DC voltage teeb liab nrog lub dav zaus band hloov suab nrov txuas nrog rau qhov kawg ntawm qhov hloov pauv lub ntsiab. Circuit Court rau hauv ib qho "huv" DC tawm tswv yim tswj teeb liab (Ue) nrog rau qee qhov amplitude, uas khaws cov DC tsawg zaus tivthaiv thiab attenuates AC high-frequency tivthaiv. Vim lub siab zaus thiab amplitude ntawm kev hloov suab nrov, yog hais tias lub attenuation ntawm high-frequency hloov suab nrov tsis txaus, cov lus qhia nyob rau hauv lub xeev yuav tsis ruaj khov; Yog hais tias lub high-frequency hloov suab nrov attenuation loj heev, dynamic teb yuav qeeb. Txawm hais tias contradictory, lub hauv paus ntsiab lus tsim rau voltage yuam kev ua hauj lwm amplifiers tseem "high low-frequency gain and low-frequency gain" Kho tag nrho kaw-voj system kom ruaj khov.
