DC transmission is an effective means to improve dynamic system performance. HVDC transmission consists of two converter stations which are connected to each other by a DC cable or an overhead DC line. By varying the firing angle (α), the DC output voltage can be controlled thereby controlling the power flow. In DC transmission, the … Read more
Many have you seen a string of circular disc like structure on transmission line structure as shown below. Some are hanging vertically and some are horizontally arranged. These are called Overhead line insulators. Fig. Overhead Line Insulators Overhead Line Insulators are used to separate line conductors from each other and from the supporting structures or … Read more
Traction is defined as ‘the act of drawing or pulling especially by a motive force‘ (drawing of carriage by horse constitute traction). In mechanical terms, it is defined as the ‘adhesive friction between the wheel and the surface on which it moves‘ (between a car tire and road). Traction system can be broadly classified as … Read more
In spite of the wide use of AC supply, DC machines have some advantages compared to ac motors and are used in industries for some applications. Some of the DC Motor Applications in Industries are listed below. Applications of DC Series Motor DC series motors are widely used for electrical traction applications, i.e, these motors … Read more
In thermal power plants, dc motors are employed for certain control and critical emergency operations which are supplied by dedicated batteries. DC motors operate as backup drives for normal ac drive systems when AC power supply to the plant is lost. In thermal power plant, the dc motors find applications for performing control functions such … Read more
Oil circuit breakers are the oldest type of circuit breakers. The separating contacts of the oil circuit breakers are made to separate within the insulating oil which has better insulating properties than air. On the occurrence of the fault as the breaker contacts open under the oil, an arc is struck between the breaker contacts … Read more
The difference between fuse and circuit breaker is given below. Fuse 1. It is generally used in low voltage application. 2. It can detect and interrupt the fault. 3. It works on the principle of electrical and thermal properties. 4. Operating time of fuse is very small. 5. Fuse element needs to replace after every operation. … Read more
Ground or earth in a main (AC power) electrical wiring system is a conductor that exists primarily to help protect against faults and which in normal operation does not carry current. Neutral is a circuit conductor that may carry current in normal operation, and which is usually connected to earth. In-house wiring, it is the … Read more
Usage of Single Computer for control of all the process variables of a plant would result in the loss of control activities in the plant if a failure occurs in the master single computer. Also, the time required for accessing large data, processing the received data and controlling of the entire plant by single computer … Read more
Question: What is a Circuit Breaker? Answer. Circuit Breaker is a mechanical device designed to close or open contact members, thus closing or opening an electrical circuit under the normal or abnormal conditions. Question: How does a Circuit Breaker different from Switch? Answer. A switch is just a device when can be able to open and close … Read more
