Construction of Thyristor
A thyristor is a four-layer semiconductor device, consisting of alternating P-type and N-type materials (PNPN). A thyristor usually has three electrodes: an anode, a cathode and a gate, also known as a control electrode.
- Thyristors have three electrodes: an anode, a cathode and a gate.
- Thyristors are four-layer semiconductors with alternating P-type and N-type materials.
- The 4-layer diode (or Shockley diode) is a type of thyristor that acts something like an ordinary diode but conducts in the forward direction only after a certain anode to cathode voltage called the forward-breakover voltage is reached.
- The 4-layer diode has two leads, labeled the anode (A) and the cathode (K).
- The symbol reminds you that it acts like a diode. It does not conduct when it is reverse-biased.
- The SCR had its roots in the 4-layer diode. By adding a gate connection, the SCR could be triggered into conduction. The SCR is the most widely used thyristor. It can switch very large currents on and off.
What is Thyristors in Power Electronics ?
Thyristors in Power Electronics are used as power semiconductor devices which are used as on/off switches in power control circuits. A power semiconductor device is a semiconductor device used as a switch or rectifier in power electronics for example in a switch-mode power supply. A thyristor is the most important type of power semiconductor device. They are extensively used in power electronic circuits. They are operated as bi-stable switches from non-conducting to conducting state. Thyristors are high speed switches that can be used to replace electromechanical relays in many circuits as they have no moving parts, no contact arcing, or suffer from corrosion or dirt. But in addition to simply switching large currents “ON” and “OFF”, thyristors can be made to control the mean value of an AC load current without dissipating large amounts of power.
Table of Content
- What is a Thyristor?
- Properties of Thyristors
- Construction of Thyristor
- Working of Thyristor
- V-I characteristics of thyristor
- Types of Thyristors in Power Electronics
- Examples of Thyristors in Power Electronics