How is Q of an inductor measured?
How is Q of an inductor measured?
The quality factor Q of the inductor is by definition = wL/R, where w is the frequency and R is the resistance of the inductor, and L is is its inductance. The integrated inductors has a complicated distributed equivalent circuit not only having self resistance but also parasitic capacitance.
How can inductance of high Q coil be measured?
Hay’s bridge is used for the measurement of inductance of high ‘Q’ coils.
Is a higher Q or lower Q desired in the oscillator?
The Q indicates energy loss relative to the amount of energy stored within the system. Thus the higher the Q the lower the rate of energy loss and hence oscillations will reduce more slowly, i.e. they will have a low level of damping and they will ring for longer.
What is Q factor measurement?
Q factor (also known as Quality Factor or Q-factor) is defined as a dimensionless parameter that describes the underdamped condition of an oscillator or resonator. The quality factor measures the performance of a coil, a capacitor, or an inductor in terms of its losses and resonator bandwidth.
What is inductor Q value?
The Q value is a parameter that indicates the quality of an inductor. “Q” stands for “Quality Factor”. Coils easily pass direct current but act as a resistor to alternating current. This behavior is called inductive reactance. The higher the frequency of the alternating current, the higher the inductive reactance.
Why Maxwell bridge is unsuitable for measuring high Q values?
The bridge is limited to measurement of low Q coils, (1 < Q < 10). It is clear that the measurement of high Q coils demands a large value for resistance R4, perhaps 10⁵ or 10⁶. The resistance boxes of such high values are very expensive. Thus for values of Q > 10, Maxwell’s bridge is unsuitable.
Which bridge is used to measure the inductance of a high Q inductor?
Hay’s bridge
Hay’s bridge is used to determine the Inductance of an inductor with a high Q factor. Maxwell’s bridge is only appropriate for measuring the values for inductors with a medium quality factor. Thus, the bridge is the advanced form of Maxwell’s bridge.
What is a high Q factor?
Q factor describes if an oscillator or resonator is underdamped, overdamped, or critically damped. Higher Q indicates that the oscillations die out more slowly (a lower rate of energy loss relative to the stored energy of the resonator).
What is Q factor for AC circuit?
Q Factor definition In an AC system, the Q factor represents the ratio of energy stored in the capacitor to the energy dissipated as thermal losses in the equivalent series resistance. For example, a capacitor that is capable of storing 2000 joules of energy while wasting only 1 joule has a Q factor of 2000.
How to calculate the quality factor of an inductor?
Minimising the resistance effects reduces the losses and increases the inductor Q factor. In order to calculate the Q, quality factor for an inductor, the formula or equation below can be used: As the resistance is equal to 2 π f L, this can be substituted in the formula to give:
What’s the high Q of a ceramic inductor?
Our 0403HQ Series ceramic chip inductors were designed for very high Q applications in a small size. They feature excellent current handling – up to 2.2 Amps and provide inductance values not available in other series of similar size. Very high Q – up to 96 at 1.7 GHz!
How does eddy currents affect the inductor Q factor?
The eddy currents dissipate energy and mean that there are losses within the inductor which can be seen as an additional level of resistance that will reduce the inductor Q factor. Radiated energy: When an alternating current passes through an inductor, some of the energy will be radiated.
Can a superconductor reduce the inductor Q factor?
This is always be present (except in superconductors which are not normally encountered). This is one of the major components of resistance in any coil or inductor and one that can sometimes be reduced. Thicker wires, and sometimes silver or silver plated wires may be used to reduce this and improve the overall inductor Q factor.