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
Magnetic field The Magnetic field is a force which is generated due to energy change in a volume of space. A magnetic field is produced by an electrical charge in motion e.g. current flowing in a conductor, orbital movement and spin of electrons. The magnetic field can be described by imaginary lines as shown in … Read more
Proportional-Integral (PI) controllers are used in many industrial control applications. The main purpose of using Proportional and Integral (PI) in process system is to improve the steady-state accuracy of the system without affecting the stability of the system. Proportional action responds quickly to the error deviation and the integral action will act slowly but offset … Read more
Frequency Response The Frequency Response of the system is the steady-state response of the system obtained as the output when a sinusoidal input signal is given to the system. For determining the frequency response of a control system sinusoidal signal is given as input to the system with different frequencies and response of the output … 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
Most of us do not know how to connect a battery either in series or parallel. A series connection is done when a greater voltage is needed. A parallel connection is done when a greater capacity is needed. Batteries joined in Series Same voltage i.e. V = 6 Volts Capacity of both batteries are added i.e. … 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
We have seen that whenever the flux, linking with a closed electric circuit changes, an EMF has induced in the circuit and a current flow, the value of which depends on the emf around the circuit and the resistance of the circuit. It is not necessary that the circuit be a wire and that the … Read more
The power rating of a transformer or any electric machines indicates the maximum value of voltage and current it can carry without over-heating. Power = Voltage(V) × Current(A) × Power factor As transformer is considered as a power source while the induction motor is considered as a load. Manufacturers of Transformers cannot predict the power … 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
