The Role of Diodes in Motor Control Circuits

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A diode is an active electronic component that is made of semiconductor material. It allows electric current to flow in one direction only. This means that when the current is flowing in the desired direction, the diode will offer minimal resistance. However, it will have maximum resistance when the current is flowing in an undesired direction. This is a key property that makes the diode applicable in various fields of electrical and electronics engineering.

One of these fields is in the motor control circuits. There are many roles that diodes play in motor control circuits. If you are working on a project related to the motor control circuit, this article is perfect for you. We are going to discuss everything about the roles of diodes in motor control circuits.

Overview of motor control circuits

To appreciate the role that didoes play in the running of motors, let’s have a brief overview of the motor control circuits. What are they and how do they operate?

As it is named, a motor control circuit is a specialized circuit type whose main role is to control the running of a motor. The motor on the other hand is used for the execution of other roles in electrical appliances. For example, in a cooling fan, the rotation of a motor will blow cool air into the space.

A motor circuit is just like any other type of electric circuit. It comprises of a power source and has wires that provide a pathway for the flow of electric current. It also has other electronic components such as diodes, resistors, capacitors, and transistors among others.

When all of these components are combined in a  single circuit, they guarantee the smooth running of the motor. They can regulate the speed of the motor switch the motor and as well as protect the motor from various electric threats.

One essential component in a motor control circuit is the power source. It generates and provides the energy that is needed in the running of the motor. The source should not only provide adequate energy but should also ensure that the energy supplied does not exceed the specified voltage and current requirement of the motor.

From the power supply, there is a need to control all the operations of the motor. This is why a typical motor control circuit should also have control mechanisms that are executed = by various electronic components, the diode being among them.  Using various control devices, you can determine the speed at which the motor rotates. Let’s not forget that the start and stop actions on the motor are performed by the control devices.

Protection components also make up the motor control circuits.  Like in most electronic applications, there must be some protection mechanisms to shield the motor from the dangers of high voltage and current. Again, there are different electronic components that play the protection role in motor control circuits. Some components will disconnect the motor from the circuit in case of a power overload

The relevance of diodes is quite clear in all these components, whether it is in the power supply, motor control devices, and motor protection devices.

What do diodes do in the motor control circuits?

Let’s discuss the key functions of diodes in the motor control circuits:

Current rectification

This seems to be the universal unction of diodes in most electronic project applications. Oftentimes, diodes are included in motor control circuits to act as rectifiers. This refers to the process of converting electric current from AC to DC form which is not only relevant but more useful.

Diodes achieve rectification in two main ways. These are the half-wave and full-wave rectifications. The ability of diodes to act as rectifiers is majorly based on their property to allow current flow in one direction only. When we look at the nature of the alternating current, there exist positive and negative waves. When a diode is introduced in the current, it cancels the negative side of the current wave. From the various parts of motor control circuits that we have discussed, rectification is on the power supply of the diode.

Diodes as protectors in the motor control circuits

Other than the motor itself, motor control circuits have other electronic components, some of which are super sensitive to unregulated electric currents.  This is where the importance of diodes comes in. They are designed to provide protection against reverse electric current.

The normal operation of control motors leads to the generation of reverse currents. Even after turning the main power off, there will be some electric current in the circuit. In some cases, the current may flow back to the circuit and to other electronic components.

Diodes are included in the circuits to work in the reverse-biased mode. This means that the reverse current will be blocked from getting into the critical components of the motor control circuits. In doing so, maximum protection is guaranteed.

Also, the fact that diodes come with rated voltage means that no voltage or current exceeding the one that has been rated will get into the circuit. Zener diodes come in handy in offering the necessary voltage protection.

Protect from the EMF interference

We know that the operation of the motor entails the generation of electromotive force (EMF). Some components in the circuits are sensitive to the effects of electromagnetic interference. Flyback diodes are connected across inductors to provide protection against EMF interference. They do this by providing an alternative path for this force to flow out of the current.

Conclusion

If you are building a device that will have an electric motor, you will definitely need to build motor control circuits. They will be responsible for running the motor. Diodes are among the key components that you will need for these circuits. The number of diodes needed will depend on the specifications of the motor control.

Once you know what you need in terms of the diodes, you can go ahead to buy from reputable diode suppliers in China. Simply state your requirements and the suppliers will strive to meet your needs.

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