SCEINCE

# What are they and how do they work?

Electrical circuits transmit alternating or direct current through closed connections between electrical components. The different arrangements and configurations of these components make different types of schemes and RLC circuits is one of them.

What are their main features and applications? What is the role of RLC in electronics? What is the difference between RLC series and parallel circuits? All these questions have an answer.

## RLC unpacking

RLC means resistor (R), inductor (L) and capacitor (C). These are the main components of RLC circuits connected in a complete loop.

The resistor is made of resistive elements (such as carbon), whose function is to induce more levels of electrical resistance than the natural ones that affect the chains. It also decreases depreciation and resonant frequency in the circuit (fr).

The inductor stores energy in magnetic fields produced by the electric current flowing through conductors, according to Faraday’s law.

A capacitor stores energy in electric fields through two or more wires, most often separated by a dielectric medium. The measurement of this “storage” is called capacity.

## What is a parallel RLC circuit?

In a parallel RLC circuit, the resistor, inductor and capacitor are connected in parallel and share a connection to the same voltage source. This is different from serial connection.

IN Parallel circuits AC RLC, the electric current is divided and all components receive the same voltage and the current is divided into each component depending on its impedance. The current does not enter parallel RLC circuits using a DC source with the same efficiency as the inductor acts as a short circuit and the capacitor acts as an open circuit.

To calculate the total current, total voltage and total resistance of an RLC circuit, we can use Ohm’s law‘s, in which the current (I), measured in amperes, is equal to the voltage (V), measured in amperes, multiplied by the resistance (R), measured in ohms (Ω):

V = IR or according to the units of measurement: V = A x Ω

If this formula is applied to the capacitor of the circuit, R is replaced by Xc, where Xc is the capacitive resistance. When applied to inductors, R is replaced by X1, where X1 is inductive resistance.

V = IXc

V = IXl

## What is impedance?

The electrical impedance is the measurement of the resistance of the current in the circuit. Despite their similarities, the impedance is not the same as the resistance, as the concept actually encompasses both the resistance and the reactance produced in AC circuits (there is no reactance in the steady current of DC circuits).

In resonance, both capacitive and inductive resistance will be equal to each other. The inductor and capacitor will also conduct a higher current at the resonant frequency.

The parallel RLC circuit equation produces a complex impedance for each parallel branch as each element becomes reciprocal to the impedance, (( 1 / Z ). The reciprocal value of the impedance is called assumption (Y). The inverse of the total impedance (ZRLC) is the sum of the inverse impedances of each component:

1 / ZRLC = 1 / ZR + 1 / ZL + 1 / ZC. In other words, the total chain acceptability is the sum of the assumptions of each component.

Otherwise, the formula for finding the impedance is Z = V / I, where Z is the impedance, V is the voltage, and I is the current of the circuit.

The total impedance is the sum of all circuit impedances.

## What is the benefit of a parallel RLC circuit?

RLC circuits are often used as oscillatory circuits because they produce sinusoidal waves, square waves or triangular waves. These are oscillating electronic signals that can converts direct current to alternating current or operate as a low pass filter, high pass filter, bandpass filter and bandpass filter.

As a bandpass filter, it is used for tuning, for example, in TVs and analog radios, which essentially allow you to find a certain frequency range after collecting all the available surrounding radio waves through an antenna. Tape filters are also used in audio equalization, audio design and studio audio recording.

As an oscillator circuit, it must have low damping values ​​to operate efficiently. In other words, it must have a high quality factor (IN). The parallel RLC circuit quality factor is the inverse of the quality factor of the series circuit.

Q = R 𝐶 𝐿 = 𝑅 𝜔0 = 𝜔0 𝑅𝐶

Are the LCR and RLC circuits the same?

Yes, what changes is the order of the symbols.

What is reactivity?

Reactivity is the opposition of a current flow component due to the effect of the inductance or capacitance caused by that component.

Just as with resistance, the more reactive a circuit has, the more limited the current it draws. But unlike resistance, reactive resistance changes phase and does not dissipate electricity; instead store it.

Reciprocity of reactivity is susceptibility, which measures the lightness at which the reactance (or set of reagents) allows AC to flow when a voltage of a given frequency is applied.

What are the differences between parallel RLC circuits and RLC series circuits?

Not only are there two different types of RLC circuits, but they also behave in effectively opposite ways:

• If the resistor, inductor and capacitor are connected in parallel in parallel RLC circuits, they are connected in series in RLC series circuits.
• The current is the same in all components of the circuit in RLC series circuits, but in parallel RLC circuits the total current is equal to the vector sum of the current of each element: Is2 = MeR2 + (I° C – IL)2.

To calculate the current of each element, we must use the formula IR = V / R, I° C = V / X° C , IL = V / XL

The same thing happens with tension, but vice versa. The voltage is different for all components in the RLC series circuits and is equal in the parallel RLC circuits.

To calculate the voltage in RLC series circuits, we must use VR= MeR, VL = IXL, V° C = IX° C
• At resonance, RLC parallel circuits are shown maximum impedance, but the RLC series circuits show minimal impedance.