Filter inductors work on the principle that inductors are resistant to resistance, and for signals of lower frequency, the resistance of inductors is small and signals can easily pass through inductors; for signals of higher frequency, the resistance of inductors is larger and signals are difficult to pass through inductors, so high frequency signals can be filtered out.
Capacitors also have resistance, for lower frequency signals, the capacitor's resistance is larger, the signal is difficult to pass through the capacitor; for higher frequency signals, the capacitor's resistance is smaller, the signal can easily pass through the capacitor.
Since the characteristics of inductors and capacitors are opposite, a capacitor filters out low-frequency signals when an inductor filters out high-frequency signals. This makes it possible to filter signals of different frequencies by adjusting the impedance of the inductor and capacitor.
Often, filtering inductors are used to filter out interfering signals in circuits to ensure signal purity. For example, in communication systems, filter inductors can be used to filter out interference Filter inductors are often used in combination with capacitors to form so-called filter circuits. Such circuits can filter out unwanted signals in a circuit, thereby improving the purity of the signal.
Filter circuits usually consist of two parts: a high-pass filter and a low-pass filter. A high-pass filter filters out low-frequency signals, while a low-pass filter filters out high-frequency signals.
The specific design of a filter circuit depends on the frequency range of the signal to be filtered. For example, a high-pass filter can be used if signals below 50 Hz need to be filtered out, and a low-pass filter can be used if signals above 50 Hz need to be filtered out.
Filtering inductors are widely used in electronic devices, for example, in communication systems, filtering inductors can be used to filter out interfering signals; in power systems, filtering inductors can be used to eliminate electromagnetic interference on power lines; in medical devices, filtering inductors can be used to eliminate electromagnetic interference and ensure the normal operation of medical devices.