The working mode and working conditions of thyristors

The working mode and working conditions of thyristors

Thyristor, also known as thyristor, is the abbreviation for semiconductor thyristor. Thyristor is a high-power PNPN type 4-layer 3-terminal component that can convert alternating current into pulsating direct current with adjustable voltage, as well as direct current into alternating current. It can also adjust the alternating current voltage and make contactless switches. Thyristors are widely used in controllable rectification, speed regulation of DC motors, and electroplating industries.

The characteristics of thyristors mainly include the following aspects:

Unidirectional conductivity: Thyristors have unidirectional conductivity and can only flow from the anode to the cathode, with very little reverse current.

Controllability: The conduction state of the thyristor can be controlled by the signal of the control electrode, which can be voltage, current, light signal, etc.

Low voltage drop: The forward voltage drop of thyristors is very small, usually only a few volts, so they have the characteristic of low voltage drop.

High current carrying capacity: Thyristors have a very high current carrying capacity, capable of withstanding currents of several hundred amperes.

High temperature tolerance: Thyristors have a very high temperature tolerance and can operate normally in high-temperature environments.

High reliability: Thyristors have a simple structure, high reliability, long lifespan, and can operate normally in harsh working environments.

In summary, thyristors have the characteristics of single conductivity, controllability, low voltage drop, high current carrying capacity, high temperature carrying capacity, and high reliability, and can be widely used in power electronic devices.

The working mode of thyristor

During the operation of a thyristor, its anode (A) and cathode (K) are connected to the power supply and load, forming the main circuit of the thyristor. The gate (G) and cathode (K) of the thyristor are connected to the device that controls the thyristor, forming the control circuit of the thyristor.

There are two main working modes of thyristors: conduction state and cutoff state.

Conductive state: When a positive pulse signal is applied to the control electrode of the thyristor, the thyristor will conduct, and current can flow from the anode to the cathode. At this point, the resistance of the thyristor is very low, and the current can flow freely. The power loss of the thyristor is also very small.

Cut off state: When a negative pulse signal is applied to the control electrode of the thyristor or there is no signal, the thyristor will cut off and the current cannot flow from the anode to the cathode. At this point, the resistance of the thyristor is very high, and the current cannot flow. The power loss of the thyristor is also very small.

The working mode of thyristor can be achieved through the signal of the control electrode, which can be voltage, current, light signal, etc. The working mode of thyristors is simple and reliable, which can achieve efficient control and regulation of power electronic devices.

Working conditions of thyristors

The working conditions of thyristors include the following aspects:

Forward voltage: The forward voltage of the thyristor should not exceed its rated value, otherwise it may cause damage or burnout of the thyristor.

Reverse voltage: The reverse voltage of the thyristor should not exceed its rated value, otherwise it may cause damage or burnout of the thyristor.

Control current: The control current of the thyristor should be large enough to ensure reliable conduction of the thyristor. Controlling the current too low can cause the thyristor to be unable to conduct or conduct unstably.

Working temperature: The working temperature of the thyristor should be within its allowable range. Excessive temperature can cause damage or burning of the thyristor.

Environmental humidity: Thyristors should avoid working in humid environments, as this can affect their performance and lifespan.

Working frequency: The working frequency of the thyristor should be within its allowable range. Excessive frequency can cause damage or burnout of the thyristor.

In short, the working conditions of thyristors should meet their specifications to ensure that they can function properly and have reliability and stability.