چی دەبێت ڕۆگۆڤسی کۆیل بێ؟

Rogowski Coil çi ye?

Rogowski Coil Pêşnûs

Rogowski Coil dike bir cihaz e ku ji bo pîvanî dîmena giranbûna (AC) û bîrên çawitandî an pulsed dîmen pîvankirin.

Rogowski Coil Xasîyeta

Rogowski Coil dike bir coil e ku bi rêjiyek nûmerîk N û herêmek bexwezî A hatî. Di Rogowski Coil de ne metal core ne. End terminali coil-a di navendeya navendeyê de derbas dike di navendeya din de. Bunaqela, hertwahî terminalên di navendeya yekem de ne.

Prinsîp Kargûn

Rogowski coils li ser Faraday’s law împeratirin, wek AC current transformers (CTs). Di CTs de, voltage induced di secondary coil de proporsiyonal e ku dîmen di conductor de be. Ferq di Rogowski coils û AC current transformers de li gorî core-ê ye. Di Rogowski coils de, air core bikar e û di current transformer de, steel core bikar e.

Heta dîmen di conductor de da, wate magnetic field tişteve. Li gorî intersection di magnetic field de, voltage induced di terminalên Rogowski coil de.

Mezinahiya voltage proporsiyonal e ku dîmen di conductor de be. Rogowski coils close pathed ne. Genelî, outputi Rogowski coils li ser integrator circuit ve şîne. Dema ku, coil voltage integrated bike ku output voltage tişteve ku proporsiyonal e ku input current signal be.

Rogowski Coil Integrator

Li gorî components bikarên di integrator de, divê types of integrator heye;

• Passive Integrator

• Active Integrator

Passive Integrator

Ji bo range yekbûhî outputi Rogowski coils, series RC circuit wek integrator karker. Mezinahiya Resistance (R) û Capacitance (C) li gorî phase error acceptable hate derketin.

Parastnayîna R û C û phase error dikare ji phasor diagram RC network re derketin. Û wekhevişandî di figure de.

Di phasor diagram de,

VR û VC nîşane dike voltage drop across the resistor û capacitor,

IT net current in the network e,

V0 output voltage e. Voltageya vê wekhevişandin voltage across the capacitor (VC) e,

VIN input voltage e. Vê vector sum of a voltage drop across the resistor û capacitor e.

Voltage drop across the resistor in-phase e û voltage drop across the capacitor will lag by 90˚ with respect to the net current.

Active Integrator

RC circuit wek attenuator karker, reducing the voltage across the capacitor. Ji low current levels re, output voltage zêdeyek jêr bibe, li mikrovolt (μV), weak signal for the Analog to Digital Converter (ADC) tişteve.

Vê pirsemana bi karîna Active Integrator sol bi teker. Circuit of an active integrator wekhevişandin di figure de.

Lê, RC element li feedback path of an Amplifier re ye. Gain of the amplifier dikare bi karîna equation below adjust bike.

Advantages of Rogowski Coil

• Dikare li ser fast-changing currents piştgiribezhêje.

• Ne danger of opening of the secondary coil ne.

• Air as medium bikar e, bi ne magnetic core. Vê prevent any risk of core saturation dikare.

• Di vê coil de, temperature compensation simple e.

Disadvantages of Rogowski Coil

• To obtain the current waveform, output of the coil must pass through the integrator circuit. It needs a power supply of 3V to 24Vdc.

• It cannot measure the DC current.