Daim phiaj Tie Inverter: 10 Kauj Ruam (nrog Duab)

2024 Tus sau: John Day | [email protected]. Kawg hloov kho: 2024-01-30 09:25

Qhov no yog qhov project nqaij yog li rub tawm!

Cov kab sib chaws khi cov inverters pab koj thawb lub zog rau hauv lub qhov (socket) uas yog lub peev xwm txaus. Kuv pom cov khoom siv hluav taws xob thiab kev tswj hwm koom nrog hauv lawv cov kev tsim nthuav kom kuv tsim kuv tus kheej. Daim ntawv tshaj tawm no qhia txog yam kuv tau kawm thiab sau cia tias kuv tau ua dab tsi. Kuv yuav txaus siab rau cov lus koj tau muaj (sib nrug los ntawm qhov uas tsis cuam tshuam nrog cov hluav taws xob loj).

Txhua lub ntsiab lus tuaj yeem hloov pauv tau tab sis qhov teeb tsa no tau tso tawm ntau tshaj ntawm 40 watts ua ntej cov lim inductors pib saturating. Cov zis tam sim no yog sinusoidal nrog THD <5%.

Saib cov software ntawm kuv GitHub

Khoom siv

• Kuv siv pawg tswj hwm kev txhim kho STM32F407. Nws khiav ntawm 168MHz thiab muaj 3 built-in ADCs muaj peev xwm ntawm 12 ntsis kev daws teeb meem ntawm ntau dua 2.4MSPS (Ntau lab Cov Qauv Ib Thib Ob) txhua. Qhov ntawd yog vwm!
• Kuv siv DRV8301 pawg thawj coj loj. Lub tsev no muaj 60v H-Choj nrog rau cov neeg tsav tsheb qhov rooj tsim nyog, tam sim no shunts thiab tam sim no shunt amplifiers. Zoo nkauj heev!
• Kuv siv lub tshuab hloov pauv toroidal 230-25v nrog 2 lub kais dej tso tawm. Qhov no txhais tau tias kuv tsis tas yuav tsim hluav taws xob ncaj qha tab sis tuaj yeem ua haujlwm nrog qhov siab tshaj ntawm 40 volts xwb. Muaj kev nyab xeeb dua!
• Kuv txuas cov khoom siv hluav taws xob thiab cov khoom siv hluav taws xob ua ke kom tau txais L thiab C qhov kuv xav tau rau lub lim.
• Lub oscilloscope thiab kev soj ntsuam sib txawv yog qhov tseem ceeb rau txoj haujlwm zoo li no. Kuv muaj Picoscope

Kauj Ruam 1: Lub Hwj Chim Dab Tsi?

Qhov koj tau txais ntawm lub qhov hluav taws xob (hauv tebchaws Askiv) yog 50Hz 230v RMS sinusoidal teeb liab nrog qhov cuam tshuam tsawg heev. Ob peb yam hais txog qhov ntawd:

50Hz - Cov zaus tseem ceeb yog tswj tau zoo ntawm 50Hz. Nws txawv me ntsis tab sis 90% ntawm lub sijhawm nws nyob ntawm 49.9-50.1Hz. Saib ntawm no. Koj tuaj yeem xav txog txhua lub tshuab hluav taws xob loj nyob hauv cov chaw siv hluav taws xob nce thiab nqis hauv lub tebchaws sib zog ua ke. Lawv tig synchronously ua rau peb 50Hz sinusoidal teeb liab. Lawv cov kev sib hloov loj heev inertia yuav siv sijhawm qeeb lossis nrawm dua.

Hauv txoj kev xav, yog tias muaj qhov thauj khoom loj tau txuas rau kab sib chaws nws yuav pib qeeb hauv lub tebchaws cov neeg tsim hluav taws xob. Txawm li cas los xij, hauv kev teb, cov hais mav hauv National Grid lub chaw haujlwm tswj hwm yuav thov cov chaw siv hluav taws xob kom tso lawv lub rhaub dej kub, ua kom sov thiab ua rau cov tshuab hluav taws xob nyuaj dua kom ua tau raws li qhov xav tau. Yog li cov khoom siv thiab kev xav tau sib koom ua las voos nrog ib leeg.

Ib qho ntxiv los hais txog 50Hz teeb liab. Txawm hais tias nws txawv me ntsis txog 50Hz, cov hais mav mus rau sab saum toj kom ntseeg tau tias qhov nruab nrab zaus ib hnub yog raws nraim 50Hz. Yog li yog tias daim phiaj nyob ntawm 49.95Hz rau 10 feeb, lawv yuav ua kom nws khiav ntawm 50.05Hz tom qab coj tus lej pes tsawg mus rau 50Hz x 60seconds x 60minutes x 24hours = 4, 320, 000/hnub. Lawv ua qhov no kom raug siv International Atomic Time. Yog li ntawd, cov khoom siv hauv tsev, chaw ua haujlwm thiab khoom lag luam tuaj yeem siv cov zaus sib xws kom khaws sijhawm. Qhov no feem ntau ua tiav nrog lub tshuab ntsaws cov timers piv txwv.

230v - Qhov no yog RMS (Root Mean Square) qhov hluav taws xob ntawm 50Hz teeb liab. Lub teeb liab tiag tiag nce mus txog 325v ncov. Qhov no tseem ceeb kom paub vim tias yog tias koj tab tom tsim lub inverter koj xav tau los tsim hluav taws xob qhov siab no yog tias koj yuav tau txais ib qho tam sim no ntws mus rau hauv cov ntsaws.

Qhov tseeb, qhov hluav taws xob pom ntawm lub ntsaws hauv koj lub tsev yog qhov sib txawv heev. Qhov no yog vim qhov poob qis hla qhov tsis kam ntawm cov xov hlau, txuas, fuses, hloov pauv thiab lwm yam. Yog tias koj qhib hluav taws xob da dej rub 11 kilowatts (uas yog ~ 50Amps) ces txawm tias 0.2ohms ntawm kev tiv thaiv yuav poob koj 10volts. Koj tuaj yeem pom qhov no zoo li lub teeb dimming puas tau me ntsis. Cov cav loj, xws li cov nyob hauv hoovers kos cov dej loj loj thaum lub cav nce mus nrawm. Yog li koj feem ntau pom qhov muag me ntsis ntawm lub teeb thaum koj qhib lawv.

Kuv lub ntsiab lus yog, qhov hluav taws xob qhov hluav taws xob muaj ntau qhov sib txawv. Ntawm no hauv tebchaws Askiv nws yuav tsum yog 230v nrog +10%/-6% kev ua siab ntev. Koj tuaj yeem cia siab tias yuav pom kev hloov pauv sai thiab hloov pauv raws li cov khoom loj nyob ze qhib/tua. Xav txog lub tshuab ziab khaub ncaws, kettles, ncu, hoovers thiab lwm yam.

Sinusoidal - Lub teeb liab yuav tsum yog qhov zoo huv huv sine yoj tab sis qhov tseeb qee cov khoom siv tsis siv kab nqus lawv lub zog los ntawm qee cov ntsiab lus hauv lub voj voog sine. Qhov no qhia txog qhov tsis sib xws thiab yog vim li cas lub teeb liab tsis yog lub zoo sine yoj. Cov khoom uas tsis yog kab feem ntau suav nrog cov khoom siv hluav taws xob khoos phis tawj, teeb taws teeb, lub roj teeb, lub TV, thiab lwm yam.

Tag nrho kev sib haum xeeb sib txawv (THD) suav qhov no hauv cov qauv yoj. Muaj cov kev cai rau kev ntxuav lub inverter cov zis yuav tsum yog li cas. Yog tias nws tsis tuaj yeem tsim lub teeb pom kev txaus txaus ces nws yuav tsis pom zoo rau kev muag. Qhov no yog qhov tseem ceeb vim tias cov ntsiab lus sib haum xeeb hauv kab sib chaws txo qhov ua tau zoo ntawm qee cov khoom siv txuas nrog nws (tshwj xeeb yog kev sib haum xeeb khib). Kuv ntseeg tias qhov tso cai THD yog 8%

Kev tiv thaiv qis - Thaum xav txog kab sib chaws khi inverter qhov no yuav yog qhov tseem ceeb los xav txog. Muaj txhua yam kev thauj khoom txuas rau lub hauv paus suav nrog inductive, tiv taus thiab qee zaum muaj peev xwm thauj khoom. Yog li tus impedance tsis paub thiab hloov pauv tau. Qhov tsis kam yog lub ntsiab lus me me yog tias koj txuas lub siab tam sim no, qhov hluav taws xob yuav tsis poob ntau ntau txhua.

Kauj Ruam 2: Yuav Ua Li Cas Thiaj Hwj Huam Rau Hauv Daim phiaj

Txhawm rau thawb lub zog rau hauv kab sib chaws peb xav tau los ua ke lub teeb liab uas haum raws qhov zaus thiab theem ntawm lub ntsiab tab sis nrog qhov hluav taws xob puas tau nce siab me ntsis.

Vim tias daim phiaj tsis muaj zog nws nyuaj rau paub qhov tseeb ntau npaum li cas los ua qhov hluav taws xob ntawd. Thiab raws li RMS qhov hluav taws xob hloov pauv peb xav tau kom ntseeg tau tias peb hloov pauv nrog nws. Tsuas yog tsim tawm 50Hz qhov hluav taws xob teeb liab me ntsis siab dua qhov hluav taws xob qhov hluav taws xob yuav tsis ua haujlwm!

PI Tswj ntawm cov zis tam sim no

Qhov peb xav tau yog lub voj tswj uas peb ntsuas tam sim tam sim no peb tab tom thawb rau hauv kab sib chaws thiab txiav kho peb qhov hluav taws xob tso tawm kom tsav lub zog tam sim no peb xav tau. Qhov no yuav hloov pauv peb cov txiaj ntsig mus rau qhov chaw tam sim no (ntau dua li qhov hluav taws xob) uas tsim nyog rau kev tsav tsheb tsis muaj kev cuam tshuam. Peb tuaj yeem ua tiav qhov no los ntawm kev siv PI (Qhov Sib Piv Sib Xws) tswj lub voj:

PI tswj lub voj tau zoo heev! Muaj 3 ntu rau lawv:

• Tus nqi ntsuas - Tam sim no peb tab tom tso rau hauv lub ntsiab
• Qhov teeb tsa - Tam sim no peb xav kom thawb mus rau lub ntsiab
• Cov zis - Cov teeb liab hluav taws xob los tsim

Txhua lub sijhawm peb hu rau PID algorithm, peb dhau qhov ntsuas tam sim no tsis ntev los no thiab cov teeb tsa uas peb xav tau. Nws yuav rov qab tus lej tsis txaus ntseeg (piv rau cov zis hluav taws xob los tsim).

Peb qhov kev tswj hwm PID tso cai rau peb xaiv qhov tso tawm tam sim no peb xav tau ntawm txhua lub sijhawm. Txhawm rau tsim 50Hz sinusoidal tso tawm tam sim no peb yuav tsum hloov pauv peb qhov kev thov tam sim no hauv qhov kev ua txhaum sinusoidal.

PID algorithm yog hu ua txhua 100us (sib npaug rau 200 zaug ntawm 50Hz voj voog). Txhua lub sijhawm nws tau hu nws tuaj yeem hloov kho ncaj qha rau qhov hluav taws xob tso tawm thiab yog li tsis ncaj qha kho qhov tso tawm tam sim no. Raws li qhov tshwm sim peb tsim cov khoom tawm tam sim no zoo ib yam li uas tau qhia hauv daim duab nrog txhua kauj ruam tshwm sim txhua 100us. Uas muab kev daws teeb meem txaus.

Feedforward tswj

Peb tuaj yeem txo qis kev ua haujlwm ntawm PI tus tswj hwm los ntawm kev ntxiv tus tswj hwm pub rau ib yam nkaus. Qhov no yooj yim! Peb paub qhov kwv yees kwv yees qhov hluav taws xob peb yuav xav tau los tsim (tib yam li qhov hluav taws xob daim phiaj tam sim ntawd). Tus tswj PI tuaj yeem sab laug ntxiv qhov me me ntxiv qhov xav tau los tsav lub zog tam sim no.

Los ntawm nws tus kheej cov khoom noj rau yav tom ntej sib phim qhov inverter qhov tso zis hluav taws xob rau kab sib chaws qhov hluav taws xob. Tsis muaj qhov tam sim no yuav tsum ntws yog tias peb ua tau zoo txaus. Kev tswj hwm pub zaub mov yog li ntawd ua 99% ntawm kev tswj cov khoom tso tawm.

Vim yog kab sib chaws tsis kam tiv thaiv, ib qho sib txawv hauv peb qhov FF tso zis qhov hluav taws xob thiab qhov hluav taws xob qhov hluav taws xob yuav ua rau muaj hluav taws xob loj. Yog li kuv ntxiv 1ohm tsis tiv thaiv ntawm inverter thiab kab sib chaws. Qhov no qhia txog kev poob, tab sis lawv yog qhov me me hauv cov phiaj xwm loj.

Kauj Ruam 3: Tsim Cov Khoom Siv Hluav Taws Xob Siv PWM

Txawm hais tias peb tsis ncaj qha tswj cov zis tam sim no, nws yog qhov hluav taws xob tso tawm uas peb tab tom tsim tawm ntawm txhua lub sijhawm. Peb siv PWM (Pulse Width Modulation) los tsim peb qhov hluav taws xob tso tawm. PWM cov cim tau yooj yim tsim los ntawm microcontrollers thiab lawv tuaj yeem nthuav dav siv H-Bridge. Lawv yog cov yoj yoj yooj yim ua los ntawm 2 qhov ntsuas, zaus F, thiab lub luag haujlwm voj voog D.

PWM waveform hloov ntawm 2 qhov hluav taws xob, hauv peb kis 0v thiab Vsupply

• Nrog D = 1.0 PWM waveform tsuas yog DC ntawm Vsupply
• Nrog D = 0.5, peb tau txais cov xwm txheej yoj nrog qhov nruab nrab qhov hluav taws xob ntawm 0.5 x Vsupply, (piv txwv li D x Vsupply)
• Nrog D = 0.1, peb tau txais lub plawv dhia ua haujlwm nrog lub sijhawm nruab nrab ntawm 0.1 x Vsupply
• Nrog D = 0.0, cov zis yog lub tiaj (DC ntawm 0v)

Qhov nruab nrab qhov hluav taws xob yog qhov tseem ceeb. Nrog lub lim qis dhau peb tuaj yeem tshem tawm txhua yam tab sis DC qhov nruab nrab nruab nrab. Yog li los ntawm kev hloov pauv PWM lub voj voog D, peb muaj peev xwm ua txhua qhov DC xav tau. Qab zib!

Ua haujlwm H-Choj

H-Choj yog ua los ntawm 4 qhov hloov pauv. Cov no tuaj yeem yog BJTs, MOSFETs lossis IGBTs. Txhawm rau tsim thawj ib nrab (0 - 180 degrees) ntawm sine wave, peb teeb tsa theem B qis los ntawm kev tig Q3 tawm thiab Q4 rau (piv txwv li thov PWM nrog D = 0). Peb tom qab ntawd ua peb qhov PWMing ntawm theem A. Rau qhov thib ib nrab, qhov twg VAB tsis zoo peb teeb tsa Phase A qis thiab siv peb PWM rau theem B. Qhov no hu ua kev hloov pauv kev puas siab puas ntsws.

MOSFETs hauv H-choj yuav tsum tau tsav los ntawm lub rooj tsav tsheb. Nov yog lub ncauj lus ntawm nws tus kheej tab sis cov nti yooj yim tuaj yeem saib xyuas nws. DRV8301 dev pawg tau yooj yim ua lub tsev H-Choj, cov neeg tsav tsheb lub rooj vag thiab cov shunts tam sim no rau peb ua txoj haujlwm no ntuj raug txim yooj yim dua.

Kauj Ruam 4: Ntsuas Tam Sim No

Txhua ceg ntawm H-Choj muaj lub zog tiv thaiv thiab lub zog sib txawv. Peb cov shunts yog 0.01ohms thiab peb cov amplifiers tau teeb tsa kom tau txais 40. Li no 1 Amp txhim kho 10mV hla qhov shunt uas tom qab ntawd ua rau 400mV.

Cov txiaj ntsig los ntawm shunt amplifiers tau nyeem los ntawm 12bit ADCs ntawm STM32F407 khiav hauv kev hloov pauv tas li. ADCs tau teeb tsa ua piv txwv txhua qhov shunt ntawm 110KSPS thiab DMA tus tswj cia li sau qhov kev hloov pauv mus rau hauv 11 lo lus ncig tsis nyob hauv RAM. Thaum ntsuas tam sim no xav tau peb hu ua lub luag haujlwm uas rov qab tus nqi nruab nrab ntawm qhov no 11 lo lus tsis.

Txij li thaum peb tab tom thov ntsuas tam sim no txhua txhua PID rov ua dua (ntawm 10KHz) tab sis sau peb 11 lo lus ADC tsis nyob ntawm tus nqi ntawm 110KHz, peb yuav tsum tau txais cov ntaub ntawv tshiab txhua txhua PID rov ua dua. Yog vim li cas siv lub lim nruab nrab, yog vim PWM hloov pauv tuaj yeem qhia cov spikes rau hauv kev sib xyaw thiab cov lim dej nruab nrab tshem tawm qhov ua piv txwv ADC zoo heev.

Lub ntsiab lus tseem ceeb los ua ntawm no: Cov ceg twg ntawm H-Choj peb siv rau kev ntsuas tam sim no? Zoo nws nyob ntawm ceg twg peb tam sim no PWMing thiab uas tsuas yog tuav qis. Cov ceg tuav qis yog qhov peb xav ntsuas peb qhov tam sim no txij li tam sim no ib txwm ntws los ntawm shunt resistor ntawm sab ntawd. Hauv kev sib piv, ntawm sab tau PWMed, thaum lub siab MOSFET nyob thiab sab qis yog tawm tsis muaj qhov tam sim no ntws los ntawm qhov qis qis. Yog li, peb hloov ceg twg peb ntsuas tam sim no raws li qhov tso zis polarity ntawm inverter. Koj tuaj yeem pom qhov no meej hauv daim duab, qhia qhov tso tawm los ntawm ib qho ntawm cov shunt amplifiers dhau ib lub sijhawm. Pom tseeb peb xav nyeem cov ntawv thaum lub me ntsis.

Txhawm rau pab debug peb cov kev nyeem tam sim no. Kuv teeb tsa Digital-to-analogue converter ntawm STM32F407. Kuv tau sau qhov kev nyeem tam sim no kuv tau txais thiab ntsuas qhov tso tawm. Koj tuaj yeem pom qhov no hauv daim duab kawg, xiav yog qhov hluav taws xob hla qhov tsis kam tawm tsam (piv txwv li. Qhov tam sim no tso tawm/1.1ohms) thiab lub teeb liab yog peb DAC tso tawm.

Kauj ruam 5: Lim cov zis

Lub lim dej tso tawm yog ib feem tseem ceeb rau kev tsim. Peb xav tau cov yam ntxwv los ntawm nws:

1. Thaiv txhua qhov kev hloov pauv siab tab sis dhau 50Hz teeb liab
2. Tsawg poob
3. Tsis txhob resonate!
4. Txhawm rau tiv nrog cov dej ntws thiab cov hluav taws xob cuam tshuam

Plaub qhov hloov pauv ntawm PWM teeb liab ntawm zaus F, Lub voj voog D, nruab nrab ntawm 0 - Vsupply volts yog: (D x Vsupply) + Sine nthwv dej ntawm qhov pib zaus F, thiab kev sib haum xeeb tom qab ntawd

Qhov no yog ci ntsa iab! Nws txhais tau tias yog peb tso peb lub PWM teeb liab los ntawm cov lim qis uas thaiv PWM qhov tseem ceeb thiab txhua yam saum toj no. Peb tsuas yog tshuav nrog DC lub sijhawm luv. Los ntawm kev hloov pauv lub luag haujlwm peb tuaj yeem tsim cov khoom hluav taws xob peb xav tau ntawm 0 - Vsupply raws li tau piav qhia.

Raws li cov yam ntxwv xav tau hais los saum toj no peb tuaj yeem tsim cov lim tawm. Peb xav tau qhov lim qis dhau los ua nrog kev tiv thaiv tsawg kawg kom tsis txhob poob. Yog li peb tsuas yog siv cov inductors thiab capacitors. Yog tias peb xaiv qhov muaj suab nrov sib nrug ntawm 1 - 2KHz peb yuav zam qhov tsis sib xws vim tias peb tsis txhaj cov cim qhia nyob ze qhov zaus ntawd. Nov yog peb cov lim tsim. Peb coj peb cov zis raws li qhov hluav taws xob hla C1.

Los ntawm kev xaiv L1 = L2 = 440uH, C1 = 8.4uF peb xam cov zaus resonant ntawm 1.85KHz. Cov no yog qhov tseem ceeb ntawm qhov tseem ceeb ib yam nkaus.

Nws yog ib qho tseem ceeb kom ntseeg tau tias peb cov inductors tsis pib saturating ntawm cov dej num uas peb xav tau. Cov inductors kuv tau siv muaj qhov tam sim no 3A. Qhov no yuav yog qhov txwv ntawm peb lub zog tsim hluav taws xob. Qhov ntsuas qhov ntsuas hluav taws xob kuj tseem ceeb rau kev txiav txim siab. Kuv siv qee qhov 450v cov khoom lag luam uas yog overkill heev hauv qhov no!

Cov phiaj xwm phiaj xwm (rau qhov sib txawv me ntsis L/C qhov tseem ceeb) tau tsim los siv LTspice. Nws qhia peb qhov ua kom pom kev sib txawv ntawm cov tswv yim sib txawv. Peb tuaj yeem pom meej qhov zaus ntawm 1.8KHz. Nws qhia tau tias 50Hz lub teeb liab yuav luag tsis tau hloov pauv qhov twg kuv tuaj yeem qhia koj li 45 KHz teeb liab tau qis dua 54dB!

Yog li cia peb xaiv peb cov PWM thauj khoom zaus kom ~ 45KHz. Los ntawm kev xaiv ntau dua PWM cov neeg nqa khoom ntau zaus, lub lim lim tuaj yeem ua kom siab dua. Qhov ntawd zoo vim nws ua rau L thiab C qhov tseem ceeb me dua. Qhov ntawd txhais tau tias cov khoom me me thiab pheej yig dua. Qhov tsis zoo yog, siab dua PWM hloov pauv ntau zaus qhia txog kev poob ntau dua hauv kev hloov pauv transistor.

Kauj Ruam 6: Ua ntu ntu thiab Zaus

Kev sib koom ua ke mus rau theem tseem ceeb thiab zaus yog dab tsi ua rau daim phiaj khi hauv inverter. Peb siv kev siv digital ntawm PLL (Phase Locked Loop) kom ua tiav qhov tseeb taug qab ntawm cov teeb liab. Peb ua qhov no los ntawm:

1. Kev ntsuas qhov ntsuas qhov hluav taws xob
2. Ua rau lub zos 50Hz sinusoidal teeb liab ntawm peb tus kheej
3. Sib piv theem ntawm peb cov teeb liab hauv zos thiab cov teeb liab loj
4. Kho qhov zaus ntawm lub teeb liab hauv zos kom txog rau theem sib txawv ntawm 2 lub cim qhia yog xoom

1) Kev ntsuas tus nqi hluav taws xob

Peb teeb tsa 3 ADC channel los nyeem kab hluav taws xob. Qhov no peb tau txais los ntawm kev faib hluav taws xob faib lub kais hloov pauv raws li qhia. Qhov no muab qhov ntsuas hluav taws xob sib txawv li ntawm 1.65v uas yog tus sawv cev ncaj qha rau ntawm daim phiaj hluav taws xob.

2) Ua kom muaj lub zos 50Hz sinusoidal teeb liabProduction peb tus kheej hauv zos 50Hz sine yoj yog yooj yim. Peb khaws lub rooj saib ntawm 256 sine qhov tseem ceeb. Peb simulated sine tus nqi tau yooj yim tau txais siv qhov ntsuas qhov ntsuas uas tig zuj zus los ntawm cov lus.

Peb yuav tsum nce peb qhov ntsuas ntawm qhov raug cai kom tau txais 50Hz teeb liab. Npe 256 x 50Hz = 12, 800/s. Peb ua qhov no los ntawm kev siv timer9 moos ntawm 168MHz. Los ntawm tos 168MHz/12800 = 13125 moos zuam peb yuav nce qib peb qhov ntsuas ntawm qhov raug.

3) Sib piv theem ntawm peb lub teeb liab hauv zos thiab lub teeb liab qhov no yog qhov txias! Yog tias koj ua ke cov khoom ntawm cos (wt) x sin (wt) dhau 1 lub sijhawm qhov tshwm sim yog xoom. Yog tias theem sib txawv yog lwm yam tshaj li 90 degrees koj tau txais tus lej tsis xoom. Ua lej:

Kev sib xyaw [Asin (t) x Bsin (t + φ)] = Ccos (φ)

Qhov no zoo kawg! Nws tso cai rau peb los sib piv cov teeb liab tseem ceeb, kev txhaum (ωt) nrog peb lub teeb liab hauv zos, kev txhaum (⍵t + φ) thiab tau txais tus nqi.

Txawm li cas los xij muaj qhov teeb meem uas yuav tsum tau hais daws: Yog tias peb xav kom muaj peb lub cim qhia kom nyob twj ywm hauv theem peb yuav tsum tau kho peb cov zaus hauv ib cheeb tsam kom ua rau Ccos (φ) lub sijhawm maximal. Qhov no yuav tsis ua haujlwm zoo heev thiab peb yuav tau txais kev taug qab tsis zoo. Qhov no yog vim tias d/dφ ntawm ɑcos (φ) yog 0 ntawm φ = 0. Qhov no txhais tau tias Ccos (φ) lub sij hawm yuav tsis txawv ntau nrog kev hloov pauv hauv ntu. Qhov ntawd puas tsim nyog?

Nws yuav zoo dua nyob rau theem hloov pauv qhov piv txwv lub teeb liab los ntawm 90 degrees kom nws dhau los ua cos (ωt + φ). Tom qab ntawd peb muaj qhov no:

Kev sib xyaw [Asin (t) Bcos (t + φ)] = Csin (φ)

Qhia txog 90 qib kev hloov pauv tau yooj yim, peb tsuas yog ntxig peb lub hauv paus ADC qhov ntsuas hluav taws xob mus rau hauv ib qho kawg ntawm qhov tsis thiab coj lawv tawm ntawm cov qauv piv txwv tom qab, sib xws rau theem hloov ntawm 90 degrees. Txij li daim phiaj zaus tsis sib txawv los ntawm 50Hz qhov txheej txheem ncua sijhawm yooj yim ua haujlwm tau zoo.

Tam sim no peb sib npaug peb qib 90 degree hloov pauv lub teeb liab nrog peb lub teeb liab hauv zos thiab ua kom muaj kev sib txuas ntawm cov khoom dhau lub sijhawm kawg (piv txwv li dhau 256 qhov txiaj ntsig kawg).

Qhov txiaj ntsig peb paub yuav yog xoom yog tias 2 lub cim qhia tau raug tswj hwm 90 degrees sib nrug. Qhov no zoo heev vim tias nws rov ua dua theem hloov peb tsuas yog siv rau lub teeb liab loj. Tsuas yog hais kom meej, tsis txhob siv lub sij hawm tseem ceeb tshaj plaws peb tab tom sim ua kom nws xoom thiab peb tab tom hloov pauv peb lub teeb liab. 90 degree theem hloov pauv qhia los ntawm 2 qhov kev hloov pauv ib leeg tawm.

Yog li Yog Integral_Result <0 peb paub tias peb yuav tsum nce peb cov oscillator zaus hauv zos kom coj nws rov qab nrog theem, thiab hloov pauv.

4) Kho qhov zaus ntawm lub teeb liab hauv zos Qhov no me ntsis yooj yim. Peb yooj yim kho lub sijhawm nruab nrab ntawm kev nce ntxiv los ntawm peb qhov ntsuas. Peb txwv nrawm npaum li cas peb tuaj yeem kho qhov sib txawv theem qhov tseem ceeb lim tawm qhov tsis zoo. Peb ua qhov no siv tus tswj hwm PI nrog lub sijhawm me me.

Thiab qhov ntawd yog nws. Peb tau xauv peb lub zos sine yoj oscillator (uas teeb tsa qhov teeb tsa tam sim no teeb tsa) kom nyob rau theem nrog lub zog hluav taws xob. Peb tau siv PLL cov txheej txheem thiab nws ua haujlwm zoo li npau suav!

Ua kom ntau zaus ntawm peb cov oscillator hauv zos tseem txo qis theem hloov pauv ntawm lub teeb liab. Txij li peb tab tom txwv qhov hloov kho zaus rau +/- 131 zuam (+/- ~ 1%) peb yuav cuam tshuam rau theem hloov pauv los ntawm +/- 1 ° feem ntau. Qhov no yuav tsis muaj teeb meem txhua lub sijhawm cov theem sib xyaw.

Hauv kev xav, yog tias qhov hluav taws xob zaus sib txawv los ntawm ntau dua 0.5Hz peb yuav plam peb qhov ntsuas phoo. Qhov no yog vim peb qhov kev txwv saum toj no ntau npaum li cas peb tuaj yeem hloov kho peb cov oscillator zaus hauv zos. Txawm li cas los xij uas yuav tsis tshwm sim tshwj tsis yog tias daim phiaj yuav tsis ua tiav. Peb kev tiv thaiv kev tiv thaiv cov kob yuav ncaws tawm ntawm qhov no lawm.

Peb ua qhov xoom hla kev txheeb xyuas thaum pib los sim peb qhov zoo tshaj plaws ntawm kev pib lub teeb liab inphase los ntawm qhov offset.

Kauj Ruam 7: Tiv thaiv koog pov txwv

Wikipedia muaj ib tsab xov xwm txaus txog txhua yam hais txog kev kauv thiab tiv thaiv cov kob. Nws kuj tseem cuam tshuam tias tib neeg thuam thiab nrov nrov ntau dua qhov tsim nyog thaum nws los txog rau lub ncauj lus no. "Auj, koj tsis tuaj yeem tsim koj tus kheej daim phiaj khi inverter, koj yuav tua lwm tus thiab lwm yam."

Raws li tau piav qhia zoo dua los ntawm kab lus wikipedia peb ntiav ob peb yam kev tiv thaiv kev nyab xeeb uas ua ke muab kev tiv thaiv tsim nyog (hauv kuv lub tswv yim):

1. Hauv qab/Tshaj qhov hluav taws xob
2. Hauv/Tshaj zaus

Peb tuaj yeem txheeb xyuas cov xwm txheej no los ntawm kev txheeb xyuas yooj yim peb cov piv txwv ntsuas hluav taws xob. Yog tias muaj dab tsi tawm ntawm whack, cuam tshuam rau H-choj thiab tos kom txhua yam rov zoo li qub.