Can a microphone generate electricity? I want to use a microphone array to convert daily sound waves

There are two main types of microphones: condenser type and dynamic coil type.

The principle of a condenser microphone is to convert sound vibrations into changes in the spacing between capacitor plates, thereby causing changes in capacitance. Then the voltage changes due to changes in capacitance, which is a very weak signal and requires Use external power to amplify the signal.

The principle of a dynamic microphone is similar to that of a generator. The main difference is its purpose: a generator converts a large amount of mechanical energy into continuous electrical energy, while a microphone converts the weak kinetic energy in sound waves into a fidelity electrical signal. .

So below we only talk about dynamic microphones.

It should be said that the sensitivity of the microphone is very high and the conversion efficiency is relatively high. However, due to the limitations of its structure and strength, and the limited energy in daily sound waves, its output voltage is relatively low. Typically only a few millivolts. For such a low voltage, many (for example, 100) microphones must be connected in series so that the voltage can have usable value, for example, before it can be rectified and stored in a capacitor. At the same time, because the current is very small, many (such as 100) microphones also need to be connected in parallel to have usable value. In this way, the lineup of this array is quite spectacular.

Unfortunately, the law of conservation of energy is still at work, and the conversion efficiency is tormenting you. The total energy of daily sound waves will not make the electrical energy emitted much stronger. It is foreseeable that the electric energy generated by a 100X100 microphone array can only drive a small speaker, and the electric power required to make the small speaker produce the same loud sound should not exceed 1 watt.

In short, this idea is imaginative, makes sense in theory, is actually quite spectacular, and will not be done in reality.

Xiaoqiang discovered that the school radio station is mainly composed of microphones, power amplifiers, speakers and other components. Among them, the dynamic microphone works based on the ______ principle

Question 1: The working principle of the dynamic microphone. It is made by using the electromagnetic response phenomenon.

When sound waves vibrate the metal diaphragm, the coil (called the voice coil) connected to the diaphragm vibrates together, and the voice coil vibrates in the magnetic field of the permanent magnet. An induced current (electrical signal) is generated. The magnitude and direction of the induced current change. The changes in amplitude and frequency are determined by sound waves. This signal current is amplified by the amplifier and then transmitted to the speaker, and the amplified sound is emitted from the speaker.

Question 2: Are the principles of moving coil microphones and earphones the same? The microphone changes and the current generates a magnetic field. The earphone changes the magnetic field and generates an electric field. Because the sound drives the diaphragm to vibrate, the magnetic material of the earpiece is uneven. Changes in the magnetic field generate current

Question 3: The principle of moving-coil microphone Moving-coil microphone (moving-coil microphone) Engineering acoustics moving-coil microphone, moving coil type microphone) is to convert the sound intoA device for electrical signals. Dynamic microphones are made using the phenomenon of electromagnetic induction. When sound waves vibrate a metal diaphragm, a coil (called a voice coil) connected to the diaphragm vibrates together, and the voice coil vibrates in the magnetic field of a permanent magnet. Among them An induced current (electrical signal) is generated. The magnitude and direction of the induced current change. The amplitude and frequency of the change are determined by the sound wave. This signal current is amplified by the amplifier and then transmitted to the speaker, and the amplified sound is emitted from the speaker.

Question 4: The working principle of the dynamic microphone in the picture is the same (C Analysis: Since the working principle of the dynamic microphone is electromagnetic induction, only the power generation in C The principle of the machine is the same, so choose C

Question 5: What are the principles of dynamic microphones and speakers? Generators and motors

Question 6: The working principle of dynamic microphones is the same as that of electrical appliances. The structure of dynamic microphones is the same as that of dynamic headphones! The working principle is the opposite! The former is that sound waves push the diaphragm! The coil on the diaphragm core vibrates in the strong magnetic gap! The latter is the coil generating an alternating magnetic field through the audio current! It interacts with the permanent magnet to cause the vibrating diaphragm to emit sound waves! How to convert sound into electronic signals in a speaker

He uses microphones. Commonly used microphones include dynamic, condenser and piezoelectric ceramics. The dynamic microphone is like a generator. The coil inside cuts the magnetic lines to generate weak current.

Condenser microphone is based on capacitor. It is inversely proportional to the distance between the two poles. When the condenser microphone vibrates, the distance between the two poles changes. When the distance becomes larger, the voltage becomes higher because the capacitance becomes smaller. At this time, an electrical signal is generated. Most condenser microphones require polarization. , there are also those that do not require polarization, called electret condenser microphones, which are commonly used in telephones and are very cheap.

Piezoelectric ceramics are a special material. When it is acted upon by a point, it will Deformation occurs, conversely, when it deforms, it also generates electricity.