Once the equivalent values of DC & AC voltages are applied to the circuit which includes an inductor connected in series through the load. So the current supply in a DC circuit is more as compared to AC circuits due to the induced voltage that opposes the flow of current within the DC circuit once the flow of current reaches its highest value. When it approaches a fixed state value, then there is no more inductive effect. In AC circuits, the flow of current will be changed continuously; so an inductive effect will occur at all times. So, this article discusses an overview of inductive reactance
What is Inductive Reactance?
Reactance can be defined as the opposition which is offered through a capacitor & inductor within a circuit to the AC flow within the circuit. It is quite related to resistance however reactance changes through the AC voltage source’s frequency which is measured in ohms. If we notice current-carrying conductors, we can discover that reactance is present always with resistance. Additionally, reactance also shows in shorter gaps because the DC changes while approaching from a stable flow.
Formula & Derivation
In an AC circuit, the inductor offers the opposition to the AC supply is known as inductive reactance. This reactance is denoted by XL and measured in ohms (Ω). Mostly, this reactance is high for high frequencies and low for low frequencies. For steady DC, it is small. The main formula for inductive reactance is given as
XL = 2 π x f x L.
From the above equation,
‘XL’ is an inductive reactance that is measured in ohms
‘2π’ is a constant (2 x 3.1416 = 6.28)
‘f’ is the AC frequency in hertz
‘L’ = the inductance value of the coil in henries.
Circuit Diagram
The circuit diagram of inductive reactance is shown below.
Inductive Rectance Circuit
Ohm’s law states that, for that applied voltage, inductive reactance can be directly proportional whereas inversely proportional to the applied current.
The equation for this is
I = V/XL
By using the above equation, we can say that voltage increasing or inductive reactance decreasing can cause a rise in current. Similarly, the flow of current will be decreased through a decrease in voltage & an increase in reactance.
Practically, the designing of an inductor must be done with wound wire as it includes some resistance consequently it is not achievable to get a purely inductive coil. Thus, an inductor there are mainly two factors that play a key role to oppose the flow of current namely resistance linked with the coil & inductive reactance given by the property of inductance.
So in an AC circuit, the complete current limiting property of an inductor is the blend of resistance as well as reactance known as impedance which is denoted with ‘Z’.
Here, Ohm’s Law is used to measure impedance value which is given like the following
Z = V / I
From the above equation
‘Z’ is the complete opposition provided through an inductor toward the flow of current in ohms
‘V’ is applied voltage
‘I’ is the flow of current in the circuit
Example
A coil with 130mH inductance with zero resistance can be connected across the supply of a 50V, 30Hz supply. So measure the coil’s inductive reactance as well as the flow of current through it.
Inductive reactance formula is
XL = 2 π x f x L.
= 2×3.14x30x0.13 =24.49 ohms
Current I = V/XL
100/24.49 = 4.08A
Inductive Reactance Dimensions
Inductive reactance is the effective opposition given by the inductor toward the current flow within the circuit. It is denoted with XL. The SI unit of inductive reactance is Ohm
I2R = ML2T-3
R = ML2T-3A-2
Reactance includes the dimensional formula of resistance
So, the dimension of this is ML2T-3A-2
So, it can be expressed like XL = LW
Difference between Inductance and Reactance
The capability of an inductor like Inductance is used to store electrical energy in the magnetic field and it can be formed through the flow of current. Energy is necessary to arrange the magnetic field and once the magnetic field drops then this electrical energy must be released. So, as a result of the magnetic field connected through the flow of current, inductors produce an opposing voltage which is comparative to the speed of change within the current flow in a circuit. Inductance can be caused by the magnetic field produced by the flow of current in a circuit.
In electric & electronic systems, the reactance can be defined as the resistance of a circuit component toward the current flow because of that inductance otherwise capacitance of element.
Better reactance can lead to less current for the similarly applied voltage. Reactance is comparable to electric resistance, however, changes in that reactance do not lead to dissipation of heat. As an alternative, energy can be stored within the reactance & afterward come back to the circuit while a resistance constantly loses electrical energy.
Effect of Frequency/Inductance
The inductive reactance formula can be determined like the following
XL= 2 π f L
In the above equation, the value of reactance can be proportional toward the inductance as well as frequency. The inductive reactance rises through either raise in inductance otherwise in frequency. So the reactance changes linearly through inductance & frequency. The resistance toward the flow of current increases while frequency or inductance increases.
When we observe the graphical representation when we plot in between the inductive reactance Vs frequency at a set inductance, at the ‘0’ frequency, the reactance is ‘0’ & once the frequency increases, the inductive reactance move on properly. When we plot the graph in-between the reactance & inductance on a set frequency when the inductor’s inductance increases, then inductive reactance can also be increased.
Please refer to this link to know more about Inductive Reactance MCQs.
Thus, this is all about an overview of inductive reactance. The reactance which is generated because of the inductor is known as inductive reactance. Inductors are also known as inductive elements which are used to store energy in the form of the magnetic field. Once an AC is given to the circuit, then a magnetic field can be formed approximately it and it can be changed like a result of an electric current. So, this resists the change of current throughout the element. Here is a question for you, what are the applications of the inductor?