Concept of Power Electronics

Power electronics is one of the contemporary subjects of electrical engineering which has seen a lot of advancements in recent times and has impacted human life in almost every sphere. We over selves use so many power electronic applications in our daily life, without even realizing it. Now the question stands as, “what is power … Read more

Two Transistor Model of SCR or Thyristor

Basic operating principle of SCR, can easily be understood by the two transistor model of SCR, as it is a combination of p and n layers. This is a pnpn thyristor. If we bisect it through the dotted line then we will get two transistors i.e. one pnp transistor with J1 and J2 junctions and … Read more

Switching or ON OFF Characteristics of SCR or Thyristor

Turn ON Time of SCR A forward biased thyristor can be turned on by applying a positive voltage between gate and cathode terminal. But it takes some transition time to go from forward blocking mode to forward conduction mode. This transition time is called turn on time of SCR and it can be subdivided into … Read more

Rating of SCR or Thyristor

Thyristor ratings or SCR ratings are very much required for operating it in a safe zone. The reliable operation can be done when a thyristor does not violate its voltage and current rating during working period. A thyristor, or SCR may have several ratings, such as voltage, current, power, , , turn on time, turn … Read more

Thyristor Protection or SCR Protection

Protection of a device is an important aspect for its reliable and efficient operation. SCR is a very delicate semiconductor device. So we have to use it in its specified ratings to get desired output. SCR may face different types of threats during its operation due to over voltages, over currents etc. There are different … Read more

Series and Parallel Connection of SCR or Thyristor

Nowadays, SCRs are available of ratings up to 10 KV and 3 KA. But sometimes we face demand, more than these ratings. In this case combination of more than one SCRs is used. Series connection of SCRs meets high voltage demand and parallel connection of SCRs meets high current demand. These series and parallel connection … Read more

Gate Characteristics of SCR or Thyristor

Gate characteristic of thyristor or SCR gives us a brief idea to operate it within a safe region of applied gate voltage and current. So this is a very important characteristic regarding thyristor. At the time of manufacturing each SCR or thyristor is specified with the maximum gate voltage limit (Vg-max), gate current limit (Ig-max) … Read more

Thyristor or Silicon Controlled Rectifier (SCR)

Silicon Controlled Rectifier (SCR) is a unidirectional semiconductor device made of silicon. This device is the solid state equivalent of thyratron and hence it is also referred to as thyristor or thyroid transistor. In fact, SCR(Silicon Controlled Rectifier) is a trade name given to the thyristor by General Electric Company. Basically SCR is a three-terminal, … Read more

Application of Power Electronics

It is literally impossible to list all the applications of power electronics today; it has penetrated almost all the fields where electrical energy is in the picture. This trend is an ever increasing one especially with present trends of new devices and integrated design of power semiconductor devices and controllers. The ease of manufacturing has … Read more

Characteristics of Thyristor or Characteristics of SCR

A thyristor is a four layer 3 junction p-n-p-n semiconductor device consisting of at least three p-n junctions, functioning as an electrical switch for high power operations. It has three basic terminals, namely the anode, cathode and the gate mounted on the semiconductor layers of the device. The symbolic diagram and the basic circuit diagram … Read more