Yuav ua li cas Capacitive Sensors ua haujlwm
Capacitive sensors siv ntau hom capacitors ua qhov ntsuas qhov ntsuas. Vim qhov kev hloov pauv ntawm tus nqi ntsuas, lub capacitance ntawm lub capacitor yuav hloov. Los ntawm kev ntsuas Circuit Court, qhov kev hloov pauv hauv capacitance tuaj yeem hloov mus rau hauv qhov hluav taws xob teeb liab tawm. Los ntawm kev ntsuas qhov loj ntawm lub teeb liab hluav taws xob, qhov ntsuas qhov loj tuaj yeem txiav txim siab. Qhov no yog lub hauv paus ntsiab lus ua haujlwm ntawm capacitive sensors.
Qhov zoo ntawm capacitive sensors
1. Zoo kub stability
Tus nqi capacitance ntawm lub capacitive sensor feem ntau yog ywj siab ntawm cov khoom siv electrode, uas yog qhov tsim nyog rau kev xaiv cov ntaub ntawv uas tsis tshua muaj kub coefficients, thiab vim nws qhov me me thaum tshav kub kub tiam, kev ruaj ntseg yog me ntsis cuam tshuam. Lub sensor kuj muaj tooj liab poob, uas yog ib qho yooj yim los tsim xoom drift vim tshav kub.
2. Cov qauv yooj yim
Lub capacitive sensor muaj cov qauv yooj yim, yooj yim rau kev tsim thiab ua kom raug siab, thiab tuaj yeem ua me me kom ua tiav qee qhov kev ntsuas tshwj xeeb; nws tuaj yeem ua haujlwm nyob rau hauv ib puag ncig hnyav xws li qhov kub thiab txias, muaj zog hluav taws xob thiab cov hlau nplaum muaj zog, thiab tuaj yeem tiv taus qhov kub thiab txias hloov, tiv taus kev kub siab, kev cuam tshuam siab, overload, thiab lwm yam; tuaj yeem ntsuas ultra- qhov kub thiab txias qhov sib txawv, thiab tuaj yeem ntsuas kev ua haujlwm sib nqus.
3. Zoo dynamic teb
Vim lub me me electrostatic attraction ntawm cov electrode daim hlau (kwv yees li ob peb 10(-5)N), lub capacitive sensor yuav tsum tau muaj zog me ntsis, thiab vim hais tias nws movable feem yuav ua tau heev me me thiab nyias, uas yog, qhov loj ntawm nws yog. Lub teeb heev, yog li nws lub ntuj zaus yog siab, lub sij hawm dynamic teb yog luv, thiab nws muaj peev xwm ua hauj lwm ntawm frequencies ntawm ob peb megahertz, uas yog tshwj xeeb tshaj yog haum rau dynamic ntsuas. Thiab vim nws qhov me me dielectric poob, nws tuaj yeem siv tau ntawm ntau zaus, yog li lub kaw lus ua haujlwm ntawm qhov siab. Nws tuaj yeem siv los ntsuas qhov hloov pauv sai.
4. Tsis yog -kev ntsuas kev sib cuag thiab siab rhiab heev
Tsis yog -kev ntsuas kev vibration lossis eccentricity ntawm cov ncej teb, radial clearance ntawm me me pob bearings, thiab lwm yam. Thaum tsis siv - kev ntsuas kev sib cuag, lub capacitive sensor muaj qhov nruab nrab, uas tuaj yeem txo qhov cuam tshuam. ntawm qhov roughness ntawm lub workpiece ntawm qhov ntsuas.
In addition to the above advantages, capacitive sensors can measure extremely low pressure, force, and small acceleration, displacement, etc. It can be made very sensitive, with high resolution, and can sense displacements of 0.01μm or even smaller. Due to its small loss of medium such as air, the zero residual generated when the differential structure is connected in a bridge type is very small, so the circuit is allowed to perform high magnification amplification, so that the instrument has high sensitivity.
Disadvantages ntawm capacitive sensors
1. Siab tso zis impedance thiab tsis muaj peev xwm thauj khoom.
No matter what type of capacitive sensor, limited by the geometric size of the electrode plate, its capacitance is very small, generally tens to hundreds of picofarads (pF), so the output impedance of the capacitive sensor is very high, up to Ω. Due to the high output impedance, the output power is small, the load capacity is poor, and it is easily affected by external interference and causes instability, and even cannot work in severe cases.
2. Cov kab mob parasitic capacitance muaj txiaj ntsig zoo.
Tus thawj capacitance ntawm lub capacitive sensor yog heev me me, thaum lub capacitance ntawm cov hlau lead cable txuas lub sensor thiab hluav taws xob Circuit Court, lub stray capacitance ntawm hluav taws xob Circuit Court, thiab lub capacitance tsim los ntawm lub capacitive phaj thiab cov nyob ib puag ncig conductors kuj loj. Lub hav zoov ntawm parasitic capacitance tsis tsuas yog txo cov kev ntsuas rhiab heev, tab sis kuj ua rau cov zis tsis tawm. Txij li thaum parasitic capacitance hloov randomly, lub sensor nyob rau hauv ib tug tsis ruaj tsis khov ua hauj lwm lub xeev, uas cuam tshuam rau qhov ntsuas qhov tseeb.